2005-05

NATO/PfP UNCLASSIFIED


NATO NAVAL GROUP 6 SPECIALIST TEAM ON SMALL SHIP DESIGN

NATO/PfP WORKING PAPER ON SMALL SHIP DESIGN

May 2004



Executive Summary

Introduction NATO Naval Armaments Group gave approval in June of 2001 to charter a Specialist Team on Small Ship Design (ST-SSD) to produce a Naval Group 6 Working Paper on acceptable criteria, standards and specifications for the design and construction of small littoral combatant (SLC) ships and offshore patrol vessels (OPVs) with displacements of approximately 600 tons to approximately 2000 tons. The propose of chartering this team, beyond development of the working paper, was to stimulate new thinking in small ship acquisition, evaluate standardized formats for NATO -PfP ship specifications, and to acquire and spread new information on technology and materials suitable for small ships. The work of the Specialist Team on Small Ship Design was carried out by the following NATO and Partner for Peace Nations: Australia, Bulgaria, Canada, Finland, Greece, Germany, Italy, Netherlands, Norway, Poland, Portugal, Romania, Russia, Spain, Sweden, Turkey, Ukraine, United Kingdom, and the United States. Specific tasks for the Specialist Team on Small Ship Design (STSSD) are outlined in the Terms of Reference and included the following:

(a) Develop a common understanding between all ST participants on design guidance and standards for small ships.

(b) Conduct a survey and compilation of national commercial and naval ship design and performance criteria, standards and specifications. Review new classification society rules for naval ships to find out their suitability to small naval ship design and construction.

(c) Make recommendations on insertions and/or modifications to relevant STANAGS and ANEPS to incorporate small ship design standards.

(d) Survey national design and acquisition processes for small ships. (e) Develop a standardized template (annotated outline format) for small ship specifications. This

template shall cover platform and combat systems (including communications). (f) Develop a compilation of technologies and materials typical to small ship designs including but

not limited to: - Modular construction - Alternative and Advanced Hull Forms - Power Systems and Propulsion Alternatives - Standardized MEP and RAS Equipment - Composite and Other Alternative Materials - Signature Management - Ship Vulnerability Reduction Measures - Sea and Air Vehicle Launch and Recovery - Manning / Human Factors / Automation / Maintenance Philosophy - Life Cycle Cost

Common Understanding of OPVs and SLCs The nations participating in this work had widely varying definitions of OPVs and SLCs. Therefore, one of the first tasks was to develop a common understanding of what is an OPV and what is an SLC. Based on a comprehensive review of existing ships, it was decided that these definitions could best be developed by first methodically defining a hierarchy of missions, operations, tasks functions and capabilities. It was agreed that naval operations could be categorized according to four operational clusters: Military Aid, Military Patrol, Military Control and Military Power. Military Aid refers to all benign operations like humanitarian assistance and disaster relief operations. Military Patrol refers to law enforcement or constabulary operations. Military Control refers to all naval sea control operations. Military Power refers to all Power Projection operations.



Both Military Control and Military Power clusters are related to operations often conducted in a medium- or high-threat environment. They are, therefore, operations typically conducted by a SLC. OPVs are specialized in conducting Military Patrol operations. Often OPV’s also have inherent capabilities to conduct humanitarian and disaster relief operations. As an alternative, SLCs can also be used to conduct Military Aid and Military Patrol. These operations, however, are often defined as their secondary mission. A similar cluster, often used when defining these secondary missions related to surface combatants, is “Peace Operations” or “Operations other than war” this is the NATO-equivalent of “Non-Article 5 Crisis Response Operations (NA5CRO) and not only refers to Military Aid and Military Patrol operations but also includes Military Control (or Sea Control) insofar as these are limited to “Peace Support Operations” as defined by the UN and implemented by NATO. Figure 1, illustrates the how these four operational clusters define the OPV and SLCs. This figure also illustrates the overlap between OPV and SLC operations.

Figure 1: Operations Template versus OPV’s and SLC’s Having established a basic understanding of the hierarchy of operations for the SLCs and OPVs, platform characteristics, performance associated with the execution of assigned tasks, and the equipment required to conduct the tasks were than agreed to. This information was then used to develop four notional designs and a limited number of trade studies that formed the basis of the teams understanding of OPVs and SLCs. The following common understanding was developed of what a SLC is and what an OPV is. Small littoral combatants and OPVs often are about the same size and operate in similar environments, but they are otherwise very different. SLCs are ships designed for operation in a dense, high threat, combat environment within the reach of ground based attack aircraft and shore based anti-ship missiles, currently meaning ships normally operating up to about 250 nautical miles offshore. Small littoral combatants conduct warfighting tasks, whereas OPVs enforce maritime law and perform search and rescue and humanitarian tasks. SLCs are far more comprehensively equipped with sensors, C4ISR systems and weapons. SLCs can vary from limited single task to larger multi-task ships that can conduct offensive or defensive missions for all types of naval warfare. Because of their limited sustainability SLCs generally operate from fixed shore bases or forward based depot ships. They generally depart, conduct an operation, and return without replenishment. As compared to OPVs, SLCs generally have much higher speed, follow naval design practices, have improved survivability and have much lower signatures

Military Power(Power Projection)

Military Control(Sea Control)

Military Aid(Benign)

Military Patrol(Constabulary)

War Operations

Peace Operations

Peace SupportOther Operations and Tasks

Small Surface Combatant (Corvette)

Offshore Patrol Vessel

Primary Operations Secondary Operations

Naval Operations Template



Because they generally are slower, OPV hulls tend to be fuller than those of SLCs, with a higher displacement-to-length ratio. Slower OPVs also have relatively less installed propulsive power. Because of the differences in task-related equipment and lack of dedicated damage control teams, OPVs can have smaller crews, particularly because they are often comprised of professional mariners in lieu of high turnover, less experienced, military personnel. High-speed SLCs have hull, mechanical and electrical equipment that is designed to meet lightweight naval standards. They have high payload-area and payload-weight fractions, austere habitability, and extensive redundancy and separation for high availability and combat survivability. The hulls of SLCs are also designed to meet demanding naval intact and damaged stability standards. Conversely, OPV propulsion plants often have specialized propulsion systems for low speed loiter operations. Most significant is the obvious difference in the ratio of payload-to-total program cost. In SLCs the proportionate allocation of program cost to the payload should be very high because of the relatively high ratio of combat system payload weight -to-light ship weight, whereas in OPVs this ratio should be expected to be much lower. Similarly, the overall cost-per-ton of SLCs is expected to be considerably higher than that for OPVs. Common Understanding of Rules and Standards One of the major objectives of the Specialist Team on Small Ship Design was to examine and reach a common understanding of the rules and standards that are applicable to small ship design. The team addressed this by examining the relevance of existing NATO publications to small ships, examining the rules and standards currently in use by the navies and coast guards of the nations participating in this study, and by examining the recently published Naval Vessel Rules of several Ship Classification Societies. The team reviewed thirty-nine NATO documents for applicability to SLCs and OPVs. Of the documents reviewed, seven were Allied Maritime Environmental Protection Publications (AMEPP), 15 were Allied Naval Engineering Publications (ANEP) and 17 were Standardization agreements. In general it was found that many of these documents are applicable or partially applicable to small ship design, however many of these documents are out dated and generally in need of revision to reflect current developments and trends in naval vessel design and operation. The study of the rules and standards employed in small ship design considered seven small combatants and six OPVs. The study included consideration of Classification Society Rules used in the design and construction of the ships, environmental regulations, requirements for personnel safety, seakeeping requirements, standards for specifying speed and powering requirements, maneuverability, accessibility requirements, survivability requirements, signature management, intact and damage stability, structural design loads and response criteria and electric system requirements. Also habitability requirements were considered. In general it was found that many nations make use of Classification Society Rules for guidance in the design and construction of the ships, however most nations did not class the ships with the Classification Society. Many nations also made use of the International Maritime Organization’s High Speed Craft Code. All of the ships considered comply with the International Maritime Organization’s MARPOL regulations. Most ships were designed to national safety regulations, however some ships were designed to either NATO ANEP 24, 25 and 26 or SOLAS requirements. Many nations employed STANAG 4154 for the specification of seakeeping requirements. Most nations utilized national standards for speed/power, maneuverability, vulnerability, signature management and stability requirements. National Acquisition and Design Processes NATO member and Partner for Peace nations employ a variety of ship acquisition strategies. Generally all nations utilize the same ship design process which consists of four phases: Pre-feasibility; Feasibility, Conceptual and Preliminary Design; Contract Design; and Detailed Design. The biggest differences in the nation’s design processes are which phases of design are accomplished within the government and which are contracted out to the ship builder, this directly influences the type of specification utilized for the ship acquisition. For design efforts that are contracted to the ship builder early in the design process high-level guidance is usually provided from the government in the form of a performance specification,



while design efforts that are developed to a high degree of fidelity under government control, usually result in the government issuing a design specification. A specification template was developed that is broad enough in scope to account for the varying acquisition processes in use. This ship specification template provides a guide from which either a unique performance specification or a design specification or both can be developed. It is anticipated that if a rigours system-engineering process is employed both a performance specification and a design specification will need to be developed before detailed design and construction of the ship can begin. Mission Modularity Smaller ships with limited capabilities automatically reduce the flexibility of the platform. Since the specific capabilities related to humanitarian assistance and peace support operations are difficult to accommodate on the same platform, other solutions are needed. A possible solution could be the development of the fleet concept based on dedicated ships optimized for specific tasks. This could lead to a need for a large diversity of ships. However, both the development and in-service costs strongly favor the limitation in the number of ship types or platforms within the fleet. This is where mission modularity can be an outcome. Mission modularity refers to the reconfigurability of the ship: task-related equipment modules; manned or unmanned off-board vehicles; task-related manning detachments; or a combination of all these elements could be used to adapt the ship to the demands of a specific missions. Mission modularity is considered from the aspect of operational flexibility during the mission, including time and the logistics required to reconfigure the ship have to be taken into account and the consequences for mission employment. It also investigating the need for accurate configuration management. Alternative and Advanced Hull Forms ANEP 52 on Advanced Naval Vehicles was published in the mid 1990’s to summarize the work of NATO group SWG/6. The vessel types covered in the ANEP were:

− Air Cushion Vehicles (ACV) − Surface Effect Ships (SES) − Small Waterplane Are Twin Hull (SWATH) − Catamaran − Trimaran − Hydrofoil

Developments of these hull form types since ANEP 52 was reviewed and developments in advanced hull forms through 2003 are discussed. In ANEP 52 the monohull was used as a basis of comparison for all of the alternatives considered. However the team found that there had been a number of developments related to monohull design for special applications that warranted coverage in this working paper. The team found a number of ships had been built since ANEP 52 was published utilizing the alternative hull forms and the state of technology had advanced somewhat, however the majority of ANEP 52 is still valid today. Power Generation and Propulsion System Alternatives Power generation systems and propulsion alternatives were also considered. It was found that the most common prime movers used for OPV and SLC were high or medium speed diesel engines, gas turbines or a combination of gas turbines and diesel engines. The most common types of propulsors in use on these types of ships were found to be fixed and controllable pitch propellers, waterjets or a combination of waterjets and propellers. The actual configuration of prime movers and propulsors is heavily dependent upon the mission profile and the life cycle cost goals of the ship and these factors need to be considered before determining the configuration of prime movers and propulsors.



Marine Environmental Protection The issue of Marine Environmental Protection (MEP) is a very significant issue for OPVs and SLCs because of their likely operation in coastal waters. The standardization of MEP equipment for OPVs and SLCs benefits from the fact that technical solutions are not specific to military shipping. Hence, and taking into consideration specific military requirements (like shock resistance), it is frequently acceptable to incorporate COTS (commercial off-the-shelf) solutions for ships of the fishing, transportation and recreation industries of relatively similar size ships and crew. Taking into consideration current practices in modern navies, the following baseline proposal for a small ship should provide complete compliance with MARPOL regulations, and probably with most NATO countries national legislation:

a) Oily water. A dry bilge system is preferable because it is much cleaner than the wet bilge system, and because it brings along advantages in respect to fire fighting.

b) Sewage. There are wide ranging sewage systems are available as COTS that are MARPOL compliant, ranging from simple toilets with individual holding tanks to complex biological and chemical treatment systems.

c) Grey water. Most COTS solutions contemplate only gravity collection to a holding tank system with a pump that is activated by a level sensor, discharging overboard.

d) Food. There are simple COTS galley sink pulpers, discharging to a holding tank or to the ship’s sewage treatment plant, or separate pulpers/shredders. Generally, food waste is submitted to grinding and/or pulping with seawater or fresh water and discharged overboard. coastal waters operations, however, deserve further investigation into this issue.

e) Other solid waste. The complex separation and separate processing currently considered to be adequate to large ships is too demanding on small ship’s weight and space resources. In order to ensure compliance with MARPOL regulations, the vessel should be equipped at least with separation bins for plastics, metal and glass, hazardous waste and medical waste.

Replenishment At Sea

From the strategic viewpoint, one of the most important capabilities of a naval force is the ability to sustain operations at sea. However, the extent of time on station depends on the rate of consumption of a variety of consumables, which include provisions, fresh water, fuel, medical stores, spare parts and ammunition. It is noted that while a ship can be continuously replenished, the limiting factor for small ships will be the crew’s endurance to physical and mental fatigue.

Small ship Replenishment at Sea (RAS) requirements are extremely variable. It is of no operational gain to fit a small ship with RAS arrangements to permit it to operate for an unlimited period of time at sea if crew fatigue becomes critical after a given period at sea.

As a baseline proposal for small ship RAS arrangements, probably the most sensible concept would simply be some form of fuel and solids receiving, associated with VERTREP as a second line of emergency procedures (for example, evacuation of sick personnel). Materials Materials appropriate for the construction of OPVs and SLCs were also addressed. It was noted that steel is still the most common material used to construct OPVs and SLCs, however aluminium and composites are increasingly being used because they can result in lighter weight and thus increase speed and decreased draft. Composites also can be beneficial in reducing some signatures of small ships.



Over the last 20 years new metallurgical processes have resulted in the development of new micro structures, new chemical compositions and thermal treatments for steels which have combined to double of the elastic limit of steel from 230N/mm2 to over 500N/mm2. In addition current steels have resulted in greater toughness, and the weldability of some steels has been significantly improved, for example by reducing the need for pre-heating. There have not been any significant recent advances in the aluminium alloys used in the construction of small naval ships. However, because of its low weight, the use of aluminium remains a popular choice despite problems associated with softening of the heat affected zone due to welding, low resistance to high temperatures and the susceptibility to certain types of corrosion. There has been significant interest in the use of composites to construct high-speed military ships over the last ten years because of the advantages of high strength and lower weight, reduced signatures (radar and magnetic), and low preventative maintenance costs. Carbon fiber is much stiffer than glass fiber and hence allows composite materials to be feasible for larger ships, but carbon fiber remains very expensive. The primary reasons that composites have not gained greater acceptance for use in military ships is that design methods and testing supporting the development of design criteria are not well documented. There are still concerns with fire resistance and toxicity of burning resins and material properties of structure are still highly dependent on the skill of the work force and can vary considerably from yard to yard and work crew to work crew. Additionally uniform quality assurance and test procedures have not been established. Signature Management Given the missions many OPVs and SLCs are required to perform, the management of ship signatures, is necessary for many of these missions to be successfully executed. Today ship signatures above the water surface consist of Optical, Radar, Emitted signals, Infrared and other signatures while the underwater signatures consist of Electric, Pressure, Acoustic, Magnetic, and Wake. Managing or controlling ship signatures adds significantly to the construction and life cycle cost of the ship and for this reason signature management and the associated costs should be included in the discussions of the missions of the ship and the perceived threats to the ship. Ship signatures are generated by either pressure waves or electro magnetic waves. Pressure waves can be further segregated into noise (high frequency) or pressure (low frequency) and electromagnetic waves can be segregated into radio and radar waves, heat radiation, visible light and eletromagnetic field disturbances. Different signatures are detected with different types of sensors. To be able to avoid detection in most operating areas all threat sensors must be taken into account. Signature management must lead to a balanced approach to prevent any type of sensor to break through. This, once again, is connected to the type of mission and the threat of the ship. This may sometimes result in a conflict since it can be hard to simultaneously manage radar, infrared and optical signatures. Design and choice of hull superstructure materials that are suitable for radar cross section reduction may often also be suitable for other signature aspects. Vulnerability Reduction Vulnerability reduction is a primary objective in the design of all military ships. However it’s a particular challenge for small OPVs and SLCs. Given the inherent constraints applicable to SLCs, the vulnerability reduction considerations for SLCs cannot follow frigate practice. Moreover SLCs are often more likely to be engaged by small craft, terrorists or shore defenses and therefore have to consider ballistic protection against very different threats than larger combatants. Defeating small caliber (7.62 to 23 mm) projectiles and/or terrorist rocket propelled grenades can be relatively more demanding than providing enhanced fragment protection, or even constraining the damage caused by larger warheads. Conversely SLC design might still address less catastrophic threats. These include:



• Ballistic protection against small caliber weapons and/or terrorist threats, • Shock protection against mines and near miss weapons, • NBC attack

The prioritization and resources allocated to these threats will depend on mission requirements. Sea and Air Vehicle Launch and Recovery A survey of recently launched OPVs and SLCs revealed that the most common means of launching and recovering small boats are either by a ramp built into the stern of the ship or by a single point davit, either a slewing arm or pivoting arm type. Many of the designers of the most recently commissioned ships selected a stern ramp as a means to launch and recover the small boat because this method required fewer personnel to recover the boat, the costs to maintain the system were less, while the boats could be launched and recovered in similar environmental conditions the boats recovered using davits. A survey of research facilities also indicated that many ships currently being designed where also investigating through model testing the effectiveness of boat launch and recovery via stern ramps. Many of the tasks of OPVs and SLCs today also necessitate that medium and heavy weight helicopters be integrated with these small ships to perform in advanced sea conditions. In addition, there is growing interest in being able to launch and recover unmanned aerial vehicles from these types of ships. The problem with small ships is that as ship displacement decreases, ship motions increase, which elevates the need for operational guidance and places greater demand on the securing and handling equipment. Additionally because the size of the crews of the ships being studied is limited, manual securing and traversing of the helicopter places a great burden on the crew. Another significant challenge for recovering aircraft on small ships is providing the pilot with accurate and current guidance on when it is safe to land on the deck of the ship during periods of reduced visibility, high seas and at night and securing and handling the aircraft once it is on the deck. Securing systems and combination securing and traversing systems are available from a number of manufacturers that are suitable for use on small ships. Today work is ongoing to optimize a number of systems to extend the range of helicopter operations and make them safer. These systems include approach and landing guidance systems, securing systems and combination securing and traversing systems. The approach and landing guidance systems and securing systems offer great promise in improving helicopter launch and recovery capabilities of small ships. Manning Management Manning has become a major issue in the design of all military ships. While different countries have different philosophies on manning, driven primarily by political considerations, all nations realize that the way the ship will be manned has significant influence on the acquisition and life cycle cost of the ship. Manning is just one part of the management concept of how the ship will be operated and maintained. It is recognized that the development of management concepts and optimizing crew size is independent of the size of the ship; the same analysis principles should be followed for a frigate as for a SLC. This paper outlines a method for developing a management concept for small military ships and provides an example application of this method for the four notional designs discussed earlier. Life Cycle Cost Life cycle costs for OPVs and SLCs are investigated, with focus on the major elements contributing to the life cycle cost of these ships. The life cycle costs of the four notional designs are derived and compared with the life cycle cost of a representative frigate to understand the cost implications of operating small military ships. It is shown that both acquisition cost and annual operating cost per ton decreases as displacement increases. Also it is shown that the cost to build and operate an OPV is much lower then



the cost to build and operate a SLC and that SLCs are expensive relative to frigates or other larger surface combatants. Recommendations The Terms of Reference for NATO Naval Group 6, Specialist Team on Small Ship Design established a board set of tasks to be accomplished in a relatively short period of time. All of these tasks have been accomplished; some in greater detail than others, however there are a number of recommendations that have developed as a result of this work:

(a) Establish a Specialist Team on Mission Modularity to address mission analysis and systems engineering processes to support decision and design aspects of incorporating modularity into naval ships.

(b) Establish a Specialist Team to address launch/recovery of Unmanned and Manned Vehicles. (c) Establish a Specialist Team to address survivability and Vulnerability of Small Ships to

Asymmetrical Threats. This team should be open to Partners for Peace (PfP) Nations. (d) Establish a Specialist Team on Composite Materials to address application and design of

composite materials in naval vessels. (e) Establish a Specialist Team to update ANEP 52 on Advanced/Alternative Hull Forms to

address developments with multihulls and monohulls since ANEP 52 was published.



NATO/PfP Working Paper Small Ship Design

TABLE OF CONTENTS

PAGE 1.0 Introduction .................................................................................................................. 1 1.1 Background...................................................................................................... 1 1.2 Scope .............................................................................................................. 1 1.3 Aim of the Specialist Team on Small Ship Design............................................... 2 1.4 General Work Process...................................................................................... 2 2.0 Terminology and Definitions .......................................................................................... 4 2.1 Technical Terms and Definitions ........................................................................ 4 2.2 Acronyms......................................................................................................... 4 3.0 Offshore Patrol Vessels and Small Littoral Combatants................................................... 7 3.1 Definition of Ship Types .................................................................................... 7 3.1.1 Introduction............................................................................................. 7 3.1.2 General Missions Requirement ................................................................ 7 3.1.3 Tasks ..................................................................................................... 12 3.1.4 Task-Related Characteristics ................................................................... 14 3.1.5 Task-Related Equipment ......................................................................... 15 3.1.6 Ship Characteristics ................................................................................ 17 3.1.7 Summary ................................................................................................ 17 3.2 Small Littoral Combatants and Offshore Patrol Vessels....................................... 18 3.2.1 Introduction............................................................................................. 18 3.2.2 600-Tonne Offshore Patrol Vessel............................................................ 23 3.2.3 2000-Tonne Offshore Patrol Vessel .......................................................... 25 3.2.4 600-Tonne Small Littoral Combatant......................................................... 27 3.2.5 2000-Tonne Small Littoral Combatant ....................................................... 31 3.2.6 Comparison of Offshore Patrol Vessels and Small Littoral Combatants....... 35 3.3 Acquisition Costs.............................................................................................. 37 3.4 Sensitivity Studies ............................................................................................ 41 3.4.1 Introduction............................................................................................. 41 3.4.2 600-Tonne Offshore Patrol Vessel Studies ................................................ 46 3.4.3 2000-Tonne Offshore Patrol Vessel Studies .............................................. 47 3.4.4 600-Tonne Small Littoral Combatant Studies ............................................ 48 3.4.5 2000-Tonne Small Littoral Combatant Studies ........................................... 51 4.0 Rules and Standards Applied in Small Ship Design ........................................................ 61 4.1 Introduction ...................................................................................................... 61 4.2 Review of NATO ANEPS and STANAGS ........................................................... 61 4.3 Rules and Standards Applied in Small Ship Design – Top Level Comparison ....... 63 4.4 Review of Classification Society Rules for Naval Ships ....................................... 65 5.0 Small Ship Design, Acquisition and Specification ............................................................ 67 5.1 Introduction ...................................................................................................... 67 5.2 National Design and Acquisition Processes ........................................................ 67 5.2.1 Netherlands ............................................................................................ 67 5.2.2 United States Navy/Coast Guard.............................................................. 68 5.2.3 Turkish Navy ........................................................................................... 68 5.2.4 Portugese Navy ...................................................................................... 69 5.2.5 Italian Navy ............................................................................................. 70




TABLE OF CONTENTS (continued)

PAGE 5.2.6 Norwegian Skjold Class FPB Acquisition Process ..................................... 71 5.2.7 Finnish Navy ........................................................................................... 71 5.2.8 Ukraine................................................................................................... 72 5.2.9 Polish Navy ............................................................................................ 73 5.2.10 Swedish Navy ....................................................................................... 74 5.3 Standardized Specification ................................................................................ 74 5.3.1 Introduction............................................................................................. 74 5.3.2 Scope..................................................................................................... 75 5.3.3 Organization ........................................................................................... 76 6.0 Small Ship Technology ................................................................................................. 77 6.1 Mission Modularity............................................................................................ 77 6.1.1 Introduction............................................................................................. 77 6.1.2 What is Mission Modularity?..................................................................... 77 6.1.3 Applications ............................................................................................ 78 6.1.4 Design Characteristics............................................................................. 80 6.1.5 Advantages and Disadvantages ............................................................... 81 6.1.6 When is Mission Modularity an Option? .................................................... 82 6.1.7 Seaframe versus Candidates for Modularization........................................ 86 6.1.8 Cascaded Modularity............................................................................... 87 6.1.9 Mission Modularity: Old Solution With New Perspectives ........................... 87 6.2 Alternative and Advanced Hull Forms ................................................................ 88 6.2.1 Introduction............................................................................................. 88 6.2.2 Monohull................................................................................................. 90 6.2.3 Air Cushion Vehicles ............................................................................... 91 6.2.4 Catamaran.............................................................................................. 95 6.2.5 Surface Effect Ships ................................................................................ 98 6.2.6 Small Waterplane Area Twin Hull ............................................................. 102 6.2.7 Trimaran ................................................................................................. 102 6.2.8 Hydrofoil……………………………………………………………………………. 106 6.3 Power Systems and Propulsion Alternatives ....................................................... 107 6.3.1 Introduction............................................................................................. 107 6.3.2 Types of Power Generation...................................................................... 108 6.3.3 Diesel Engines ........................................................................................ 110 6.3.4 Gas Turbines .......................................................................................... 111 6.4 Standardized Marine Environmental Protection Equipment.................................. 112 6.4.1 Introduction............................................................................................. 112 6.4.2 Problem Definition – Evaluation of Waste Stream Produced by Small Ships 113 6.4.3 Shipboard Waste Abatement Policies ....................................................... 113 6.4.4 MEP Requirements in Small Ship Design ................................................. 114 6.4.5 Proposal for a Baseline MEP Equipment Plant for Small Ships ................... 115 6.5 Standardized Replenishment at Sea (RAS) Equipment ....................................... 116 6.5.1 Introduction............................................................................................. 116 6.5.2 Problem Definition – Evaluation of Replenishment Requirements Applicable to Small Ships......................................................................................... 116 6.5.3 RAS Requirements in Small Ship Design .................................................. 117 6.5.4 Proposal for a Baseline RAS Arrangement for Small Ships ........................ 117




TABLE OF CONTENTS (continued)

PAGE 6.6 Composite Materials and Comparison with Other Materials Commonly Used for Naval Shipbuilding ............................................................................................ 117 6.6.1 Steel....................................................................................................... 118 6.6.2 Aluminum Alloy ....................................................................................... 120 6.6.3 Composite Materials................................................................................ 120 6.6.4 Fibers ..................................................................................................... 122 6.6.5 Resins .................................................................................................... 123 6.6.6 Single Skin and Sandwich Configuration ................................................... 123 6.6.7 Advantages of Composites ...................................................................... 124 6.6.8 Disadvantages of Composites .................................................................. 125 6.6.9 Significant Experiences with FRP Solutions .............................................. 125 6.7 Signature Management ..................................................................................... 131 6.7.1 Radar Cross-Section Signatures (RCS) .................................................... 132 6.7.2 Infrared Signature (IR)............................................................................. 134 6.7.3 Acoustic Signature .................................................................................. 135 6.7.4 Electromagnetic Signature....................................................................... 135 6.7.5 Optical Signature..................................................................................... 136 6.7.6 Wake Signature ...................................................................................... 136 6.7.7 Electromagnetic Emissions/Electromagnetic Compatibility ......................... 137 6.7.8 Pressure Signature.................................................................................. 137 6.8 Small Surface Combatant Ship Vulnerability Reduction Measures ....................... 138 6.8.1 Vulnerability Reduction Objectives ........................................................... 138 6.9 Sea and Air Vehicle Launch and Recovery ......................................................... 143 6.9.1 Size of Ship ............................................................................................ 143 6.9.2 Type and Size of Small Boat .................................................................... 144 6.9.3 Types of Systems.................................................................................... 144 6.9.4 Ramp Design Considerations ................................................................... 144 6.9.5 Equipment .............................................................................................. 145 6.9.6 Launch and Recovery Operations ............................................................ 146 6.9.7 Design and Operational Sea States .......................................................... 147 6.9.8 Manning Requirements............................................................................ 148 6.9.9 Stern Wake Influence on Recovery........................................................... 149 6.9.10 Conclusion ............................................................................................ 149 6.9.11 Other Boat Launch and Recovery Systems............................................. 149 6.9.12 Aircraft Launch and Recovery Systems................................................... 150 6.10 Manning/Human Factors/Automation/Maintenance Philosophy ............................ 151 6.10.1 Introduction ........................................................................................... 151 6.10.2 Manning Concepts ................................................................................ 152 6.10.3 Application of Manning Theory ............................................................... 158 6.10.4 Manning Trends and Future Research.................................................... 171 6.11 Life-Cycle Cost................................................................................................. 175 6.12 Corrosion and Antifouling.................................................................................. 182 6.12.1 Influencing Variables ............................................................................. 182 7.0 Conclusions and Recommendations .............................................................................. 184 7.1 Conclusions……………………………………………………………………………….. 184 7.2 Recommendations……………………………………………………………………….. 185 8.0 References .................................................................................................................. 186




APPENDICES

9.1 600-Tonne OPV Synthesis Model Output 9.2 2000-Tonne OPV Synthesis Model Output 9.3 600-Tonne SLC Synthesis Model Output 9.4 2000-Tonne SLC Synthesis Model Output 9.5 Ship Rules and Standards Comparison Table 9.6 Characteristics of Ships Considered in Rules and Standards Comparison 9.7 Specification Template 9.8 Hull Form 9.9 Waste Stream Categories 9.10 Worked Example of OPV & FPB Waste Steams 9.11 Worked Example of OPV & FPB RAS Requirements 9.12 Example of the Royal Australian Navy’s RAS Arrangements Onboard Small Ships 9.13 Signature Management 9.14 Protection Against A Nuclear Electro Magnetic Field (NEMP) 9.15 Damage Radii and Fragment Density Reduction 9.16 Proposal for the Strengthening of Deck Stringers




LIST OF FIGURES

PAGE 3.1-1 Hierarchy of Missions, Operations, Tasks, Functions and Capabilities .............................. 7 3.1-2a Military Employment versus Functional Spectrum ........................................................... 8 3.1-2b Military Employment versus Sustainability Spectrum ....................................................... 8 3.1-3 Small Ship Design Operations Template versus OPVs and SLCs .................................... 9 3.1-4 Small Ship Design Operations Template ........................................................................ 10 3.1-5 SLC – Capability versus Size ........................................................................................ 14 3.2-1 600-Tonne OPV Inboard Profile & Summary of Ship Characteristics................................ 23 3.2-2 2000-Tonne OPV Inboard Profile & Summary of Ship Characteristics .............................. 25 3.2-3 600-Tonne SLC Inboard Profile & Summary of Ship Characteristics................................. 28 3.2-4 2000-Tonne SLC Inboard Profile & Summary of Ship Characteristics............................... 31 3.2-5 Comparison of Arrangeable Deck Area .......................................................................... 36 3.2-6 Comparison of Light Ship Displacement ......................................................................... 37 3.3-1 Relative Lead Ship Costs.............................................................................................. 39 3.3-2 OPV vs. SLC Distribution of Lead Ship Costs ................................................................. 39 3.3-3 OPV vs. SLC Platform Cost/Light Ship Tonne ................................................................ 40 3.3-4 OPVs vs. SLCs Total Cost per Tonne ............................................................................ 40 3.4-1 Impact of Added Hull or Superstructure Volume……………………………………………….. 59 5.3-1 Needs versus System Requirements ............................................................................. 75 5.3-2 Total-System Approach................................................................................................. 75 6.1-1 Blohm + Voss MEKO(R) Concept .................................................................................... 77 6.1-2a Standard Inferface FLEX Container ............................................................................... 78 6.1-2b FLEX Container Placed Onboard................................................................................... 78 6.1-2c Module for 76mm Gun .................................................................................................. 78 6.1-3 STANFLEX Concept ..................................................................................................... 79 6.1-4 Role Flexibility of STANDARD FLE X 300 ....................................................................... 80 6.1-5 Tasks of Both a Multi-Mission Frigate and an OPV Executed by a Corvette Using Mission Modularity........................................................................................................ 81 6.1-6 Mission Requirements Breakdown Structure .................................................................. 82 6.1-7 Relationship between Generic Function versus Tasks..................................................... 83 6.1-8 Ship Functions vers us Applicable Mission Modularity...................................................... 84 6.1-9 Capabilities Matrix – Tasks versus Functions ................................................................. 85 6.1-10 Generic Tasks Related to the Four Clusters of SSD Operations....................................... 85 6.1-11 Capabiities Matrices ..................................................................................................... 86 6.1-12 ASW FLEX-Container Onboard Danish STANFLEX........................................................ 86 6.2-1 Section Through Side Seal Assembly ............................................................................ 95 6.2-2 Low-Profile Bow Thruster Nozzle................................................................................... 96 6.2-3 Catamaran Hull Configuration ....................................................................................... 97 6.6-1 Typical Single-Skin Construction ................................................................................... 124 6.6-2 The FRP-Sandwich Principle: Two Stiff Faces Separated by a Light Core Material .......... 124 6.6-3 Italian Light Combatant Vessel ...................................................................................... 125 6.6-4 FRP Superstructure for Fourth Vessel............................................................................ 126 6.6-5 Composite Assembly Sequence .................................................................................... 127 6.6-6 Single Skin Reinforced with Stiffeners ............................................................................ 127 6.6-7 Sandwich Construction Reinforced with Stiffeners .......................................................... 128 6.6-8 Visby Corvette.............................................................................................................. 128 6.7-1 Signatures ................................................................................................................... 131 6.7-2 Reflection Angle ........................................................................................................... 132 6.7-3 Example of Magnetic Signature ..................................................................................... 136 6.10-1 Personnel in Ship Control Center (SCC), Controlling and Monitoring Platform Systems..... 151 6.10-2 Waterfall Principle......................................................................................................... 152




LIST OF FIGURES (continued)

PAGE 6.10-3 Peak Load and Workload.............................................................................................. 153 6.10-4 Action State Generates a High Workload and Peak Load................................................ 153 6.10-5 Mechanization of Seamanship Could Reduce the Total Amount of Crew.......................... 154 6.10-6 Difference in the Division of Quick Reaction and Support Personnel in Present Situation and With a Reduced Crew ............................................................................................ 155 6.10-7 Example of a 8+4 Working Schedule ............................................................................. 156 6.10-8 An Example of a Modular Team: A Boarding Team Inspects a Vessel............................. 157 6.10-9 Central Messing ........................................................................................................... 160 6.10-10 Remote Knowledge ...................................................................................................... 161 6.10-11 Chilled Water System ................................................................................................... 162 6.10-12 SCC Console on the Bridge of HNLMS Rotterdam.......................................................... 168 6.10-13 Basic Crew................................................................................................................... 169 6.10-14 Example of Final Crew List............................................................................................ 170 6.10-15 Central Messing ........................................................................................................... 171 6.10-16 Knowledge-at-a-distance .............................................................................................. 172 6.10-17 Chilled Water System ................................................................................................... 173 6.10-18 SCC Console on the Bridge of HNLMS Rotterdam.......................................................... 174 6.11-1 Cash Flow Diagram for Life-Cycle Costs ........................................................................ 176 6.11-2 Cash Flow Diagram for Life-Cycle Costs, with Effects of Inflation ..................................... 177 6.11-3 Ship Total Ownership/Life-Cycle Cost Composition ........................................................ 180 6.11-4 Distribution of Annual Costs .......................................................................................... 181 6.11-5 Annual Life-Cycle and Acquisition Cost versus Displacement .......................................... 181




LIST OF TABLES

PAGE 3.1-1 OPVs vs. SLCs – Tasks................................................................................................ 13 3.1-2 OPVs vs. SLCs – Task-Related Characteristics.............................................................. 15 3.1-3 OPVs vs. SLCs – Task-Related Equipment .................................................................... 16 3.1-4 OPVs vs. SLCs – Ship Characteristics........................................................................... 17 3.2-1 Design Study Performance Specification........................................................................ 18 3.2-2 Design Study Margins ................................................................................................... 22 3.2-3 600-Tonne OPV, Required Deck Area ........................................................................... 24 3.2-4 2000-Tonne OPV, Required Deck Area.......................................................................... 26 3.2-5 600-Tonne SLC, Payload Characteristics....................................................................... 29 3.2-6 600-Tonne SLC, Required Deck Area............................................................................ 30 3.2-7 2000-Tonne SLC, Electronics Payload ........................................................................... 32 3.2-8 2000-Tonne SLC, Weapons and Aviation Payload .......................................................... 32 3.2-9 2000-Tonne SLC, Ammunition....................................................................................... 33 3.2-10 2000-Tonne SLC, Payload-Related Area ....................................................................... 33 3.2-11 2000-Tonne SLC, Required Deck Area .......................................................................... 34 3.2-12 Comparison of OPV and SLC Characteristics................................................................. 35 3.3-1 Netherlands and U.S. Coast Guard Cost Estimating Factors ........................................... 38 3.4-1 600-Tonne OPV Studies ............................................................................................... 42 3.4-2 2000-Tonne OPV Studies ............................................................................................. 43 3.4-3 600-Tonne SLC Studies ................................................................................................ 44 3.4-4 Summary of Ship Characteristics, 2000-Tonne SLC Studies............................................ 45 3.4-5 Summary of Results, Volume and Weight Studies .......................................................... 56 4.3-1 NATO Small Ships Considered in Standards/Rules Comparison...................................... 64 4.4-1 Principal Characteristics of Vessel Used for Comparative Calculations............................. 65 4.4-2 Design Global Moments in MN*m, Specified by the Rules ............................................... 66 6.2-1 List of ACVs Built Since 1995........................................................................................ 93 6.4-1 Waste Management Strategies (AMEPP-4, Summary of Table 5A).................................. 113 6.6-1 Material Composition and Mechanical Properties ............................................................ 119 6.6-2 Fiber Characteristics..................................................................................................... 122 6.6-3 Typical Values of Modulus and Strength of Unidirectional Laminates, Considering Vf≅0.50 (volume fraction of fiber) ............................................................................................... 123 6.6-4 Comparison of Main Materials for Use in Naval Vessels.................................................. 130 6.7-1 Geometries Contribution to Radar Cross-Section (RCS) ................................................. 133 6.8-1 Vulnerability Reduction Measures versus Ship Size and Threat ....................................... 141 6.9-1 Ship and Ramp Characteristics ..................................................................................... 144 6.9-2 Ship and Boat Characteristics ....................................................................................... 146 6.9-3 Launch Characteristics ................................................................................................. 146 6.9-4 Recovery Characteristics .............................................................................................. 147 6.9-5 Ship and Boat Operating Characteristics........................................................................ 148 6.11-1 Traditional Vessel Life-Cycle Cost Breakdown Structure ................................................. 178 6.11-2 Summary of Annual Costs............................................................................................. 180



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1.0 INTRODUCTION

1.1 Background NATO has developed and published numerous Standardization Agreements (STANAGs) and Allied Naval Engineering Publications (ANEPs) to define criteria for naval ship design and equipment. These criteria are normally intended for frigate-sized and larger ships and may not be suitable for smaller ship types. Trends toward littoral warfare and higher speeds mean that some nations may develop smaller, lighter, highly optimized and even unconventional ship types. For these ship types, it is not always possible to use equipment or ship systems which are planned and constructed for frigates or larger ship types.

There are a limited number of NATO standards for ship types like fast patrol boats (FPB) and mine counter measures (MCM) vessels. However, these are not necessarily comprehensive, up to date or well known to all NATO and partner nations. Currently, in many NATO countries, there are new ship programs that are still in the early design phase which are within the ship size envelope proposed by this document. Whether they are fast attack craft (FAC), multipurpose corvettes, Offshore Patrol Vessels (OPVs) or MCMs, these projects may offer new information to this study. Likewise, this study can provide useful guidance to these projects and their successors. At the same time, when new ship designs are needed, there is always significant pressure to reduce costs as well as the development times needed for these projects. All navies have found that cost reductions can be achieved by optimizining crews. However, this requires more automation and new ways of using the crew more efficiently. This also means that onboard maintenance must be minimized, and more rational and standardized construction methods must be found. Additionally, instead of using strict military standards, more common commercial standards are now being considered and, at least to some degree, already accepted. The intent of this study is to combine the experience and knowledge of the NATO countries’ ship design community with the know-how of Partner for Peace (PfP)-countries, which have focused more on the small ship area. This know-how can, in some cases, be more evolutionary, flexible and economical because it was developed with fewer resources and in some cases in conjunction with civilian shipyards or design offices. In many areas, these civilian shipyards and design offices are now at the leading edge of design and construction development. Ship types designed for littoral warfare using commercial standards and smaller crews are typical examples. Consequently, NG/6 proposed that a specialist team (ST) on this demanding ship technical area be established under the approval of NNAG. 1.2 Scope The NATO Naval Armament Group (NNAG) gave approval in June 2001 to convene a Specialist Team to study the area of Small Ship Design. Specific tasks for the Specialist Team on Small Ship Design (ST-SSD) are outlined in the Terms of Reference and include the following:

(g) Develop a Program of Work Schedule to achieve the aim within the time constraints (two years from start of work).

(h) Develop a common understanding between all ST participants on design guidance and standards for small ships.

(i) Conduct a survey and compilation of national commercial and naval ship design practices, performance criteria, standards and specifications. Review new classification society rules for naval ships to determine their suitability for small naval ship design and construction.

(j) Make recommendations on insertions and/or modifications to relevant STANAGS and ANEPS to incorporate small ship design standards.



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(k) Survey national design and acquisition processes for small ships.

(l) Develop a standardized template (annotated outline format) for small ship specifications. This template shall cover platform and combat systems (including communications). Using this template, develop two example specification models.

- One for a small, light littoral combatant of approximately 600 tonnes. - The second, a paramilitary/commercial standards offshore patrol vessel of approximately

1500 tonnes.

(m) Develop a compilation of technologies and materials typical to small ship designs including, but not limited to:

- Modular Construction - Alternative and Advanced Hull Forms - Power Systems and Propulsion Alternatives - Standardized MEP and RAS Equipment - Composite and Other Alternative Materials - Controlled EMI/EMC - Ship Survivability - Sea and Air Vehicle Launch and Recovery - Manning / Human Factors / Automation / Maintenance Philosophy - Life-Cycle Cost Aspects

(n) Meet periodically as required. Produce and distribute records of meetings and report progress to NG/6 at its regular meetings.

(o) Produce a final report to NG/6 in the form of an NG/6 Working Paper which proposes acceptable criteria, standards, and template specifications for the design and construction of small littoral combatant ships and offshore patrol vessels with displacements of approximately 600 tonnes and 1500 tonnes.

1.3 Aim of the Specialist Team on Small Ship Design The aim of the Specialist Team on Small Ship Design (ST-SSD) is to produce a Naval Group 6 Working Paper on acceptable criteria, standards and specification templates for small ship design and construction. These criteria, standards and specification templates would be for the design and construction of small littoral combatant ships (SLCs) and offshore patrol vessels (OPVs) of approximately 600 tonnes and 2000 tonnes 1. In addition to producing the working paper, the main goals of this study are to stimulate new thinking in small ship acquisition, evaluate standardized formats for NATO-PfP ship specifications, and to acquire and spread new information on technology and materials suitable for small ships. The work of the ST-SSD was carried out by the following NATO and Partner for Peace Nations: Australia, Bulgaria, Canada, Finland, Greece, Germany, Italy, Netherlands, Norway, Poland, Portugal, Romania, Russia, Spain, Sweden, Turkey, Ukraine, United Kingdom, and United States. 1.4 General Work Process The ST-SSD agreed that the starting point for this work would be a survey of specifications, standards and criteria from existing national small ship projects. This data would be collected and documented so that each nation was aware of the standards and criteria being used to design and build SLCs and 1 The desire of NG/6, before the work of the team began, was to limit the displacement of the ships being studied to 1500 tons or less. However early work by the team suggested that 2000 tons was a more reasonable limit for the types of ships being considered, and the team unanimously agreed to increase the range of ships being studied to 2000 tons.



3

OPVs. No attempt is made to find the single best set of standards or criteria. Typical formats and contents of specifications were considered and the most suitable parts unified to form a model for the small ship specification.

It was agreed by the team that, in developing the specification template, there was no need to establish a common ship type or size requirement because these are normally included in a ship specification. The intent is to develop a model specification that can be tailored to suit either a small generic littoral combatant with all military requirements, or a more paramilitary style ship typically employed by coast guards and based as much as possible on commercial off-the-shelf (COTS) principles. Three work breakdown structures were considered for the specification:

a) The U.S. Navy Ship Work Breakdown Structure, b) The NATO Ship Work Breakdown Structure, and c) The Swedish Navy’s Naval Installations and Material Specification.

ST-SSD members volunteered to take the lead in researching the small ship technology areas identified in the Terms of Reference. Each team member was free to seek guidance from other applicable NATO groups or rely on their own expertise to conduct this research. The technology areas were assigned as follows:

Ship Survivability – Germany Controlled EMI/EMC or Controlled Signatures – Sweden Alternative Materials and Composites – Italy MEP and RAS – Portugal Power Systems and Propulsion Alternatives – Spain Life-Cycle Cost Considerations – Greece Terrorist Threats – U.S. Navy Alternate and Advanced Hull Forms – Finland and United Kingdom Modular Construction - Spain Mission Modularity – Netherlands Sea and Air Vehicle Launch and Recovery – U.S. Coast Guard Manning/Human Factors/Automation/Maintenance - Netherlands

The volunteering nation agreed to act as liasions with other NG/6 chatered work groups on the following areas:

ST-NSM Ship Maneuverability – Germany or Sweden SG-61 Virtual Ship – Sweden or Germany ST-SC Ship Costing – Spain SG-7 Ship Combat Survivability – Italy SWG-12 Maritime Environmental Protection – Portugal SG/4 Power Generation, Control and Distribution – United Kingdom NSG on NBC Defense – Netherlands SWG/6 Advanced Naval Vehicles – U.S. Navy SWG/10 Naval EEE group



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2.0 TERMINOLOGY AND DEFINITIONS This section defines technical terms used in this working paper addressing small ship design. Most of the terms appearing in this working paper are internationally known and accepted as standard expressions. This section is divided into two parts, the first being technical terms and their definitions. The second part addresses acronyms used throughout the working paper. 2.1 Technical Terms and Definitions Anti-Air Warfare (AAW): The naval mission of detecting, identifying and tracking aircraft and missiles, neutralizing hostile aircraft and neutralizing or diverting incoming missiles. Anti-Submarine Warfare (ASW): The naval mission of detecting, identifying and tracking submarines and underwater weapons, neutralizing hostile submarines and neutralizing or diverting incoming underwater weapons. Anti-Surface Ship Warfare (ASuW): The naval mission of detecting, identifying and tracking surface ships and water craft and of neutralizing hostile ships and water craft. Capability: A type of system(s) or an individual that is required to accomplish a particular Function. Function: A specific unit action that delineates how a particular aspect of a task is to be performed. Mine Warfare (MIW): The naval mission associated with mines with the following four submissions:

1. Mine Avoidance: Detecting mines and maneuvering the ship away from the mines. 2. Mine Hunting: Detecting, identifying and neutralizing mines. 3. Mine Sweeping: Clearing mined areas by towing mechanical mine sweeping gear. 4. Mine Laying: Depositing mines in order to build up a mine barrier.

Mission: An assignment with a purpose that clearly indicates the military actions to be taken and the reasons therefore and consists of operations to be carried out simultaneously or in succession. Operation: A military action based on doctrines that supports a Mission and consists of discrete Tasks. Power Projection: the ability to project force from a maritime force into the territory of another state. Sea Control: to attain and maintain a desired degree of freedom of action within an area of the sea (surface, sub-surface, air above and coastal areas) for one’s own purposes for a period of time and, if necessary, deny its use to an opponent. Task: A discrete event/action that enables a Mission to be accomplished by individuals or organizations. 2.2 Acronyms ABS – American Bureau of Shipping ACV – Air Cushion Vehicle ADF – Air Defense Frigate AMEPP – Allied Maritime Environmental Protection ANEP – Allied Naval Engineering Publication AP – Armor Piercing B – Beam C&M – Control and Monitoring



5

C4ISR—Command, Control, Communications, Computers, Intelligence, Surveillance, Reconnaissance CB – Block Coefficient CFRP – Carbon Fiber Reinforced Plastic CIC – Combat Information Center CODAG – Combined Diesel and Gas Turbine COTS – Commercial-off-the-Shelf CP – Prismatic Coefficient CPP – Controllable Pitch Propeller CRM – Corrosion Related Magnetic CSAR – Combat Search and Rescue CX – Maximum Section Area Coefficient D&C – Design and Construction DC – Damage Control DNV – Det Norske Veritas E/O – Electro Optical ECR – Engineering Control Room EEZ – Exclusive Economic Zone EHP – Effective Horsepower ELFE – Extremely Low Frequency Electric ELINT – Electronic Intelligence EMC – Electro Magnetic Compatibility EMC – Electromagnetic Compatibility EMI – Electromagnetic Interference EMP – Electro Magnetic Pulse ESSMS – Evolved Sea Sparrow Missle System EW – Electronic Warfare F/V – Future Value FAS – Fueling at Sea FC – Fire Control FRC – Fast Response Craft GFE – Government Furnished Equipment GM – Metacentric Height GRP – Glass Reinforced Plastic HAM – Humid Air Motor HM&E – Hull, Mechanical and Electrical HSM – High Speed Machinery HVAC – Heating, Ventilation and Air Conditioning HYSUCAT – Hydrofoil-Assisted Catamaran ICCP – Impressed Current Corrosion Protection IMO – International Maritime Organization IR – Infrared ISR – Intelligence gathering, Surveillance, and Reconnaissance ITTC – International Towing Tank Conference JP-5 – Jet Propulsion Fuel JTF -- Joint Task Force KG – Vertical Center of Gravi ty LBP – Length Between Perpendiculars LCAC – Landing Craft Air Cushion LCC – Life Cycle Cost LR – Lloyd’s Register of Shipping LCS – Littoral Combat Ship MCM – Mine Counter Measures MCMV – Mine Counter Measure Vessel MEP – Marine Environmental Protection NASCRO – Non-Article 5 Crisis Response Operations NATO – North Atlantic Treaty Organization



6

NBC – Nuclear, Biological, Chemical NBCD – Nuclear, Biological Chemical and Damage Control NEMP – Nuclear Electro Magnetic Field NEO – Non-Combat Evacuation Operations NSFS – Naval Surface Fire Support OPV – Offshore Patrol Vessel P/W – Present Worth PAPS – Phased Armament Programming System PfP – Partners for Peace RAM – Radar Absorbing Material RAM – Rolling Air Frame Missle RAS – Replenishment at Sea RCS – Radar Cross Section REA – Rapid Environmental Assessment RFI – Request for Information RFP – Request for Proposal RFQ – Request for Quotation RHIB – Rigid Hull Inflatable Boat RPM – Revolutions Per Minute RS – Ready Service SAR – Search and Rescue SCC – Ship Control Center SES – Surface Effect Ship SIGINT – Signature Intelligence SLC – Small Littoral Combatant SLOC – Sea Lines of Communication SOLAS – Safety of Life at Sea SSA – Single Significant Amplitude SSD – Small Ship Design SSDG – Ship Service Diesel Generator STANAGS – Standardization Agreements SWATH – Small Waterplane Area Twin Hull TOC – Total Ownership Cost UAV – Unmanned Aerial Vehicle UEP – Underwater Electric Potential UN – United Nations USV – Unmanned Surface Vehicle UUV – Unmanned Undersea Vehicle VERTREP – Vertical Replenishment VLS – Vertical Launch System VR – Vulnerability Reduction VUAV – Vertical Take-off-and-Landing Unmanned Aerial Vehicle



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3.0 OFFSHORE PATROL VESSELS AND SMALL LITTORAL COMBATANTS 3.1 Definition of Ship Types 3.1.1 Introduction International navies and coast guards have widely varying definitions for offshore patrol vessels (OPVs) and small littoral combatants (SLCs). Based on a comprehensive review of existing ships, it was decided that these definitions could be best developed by methodically analyzing each type of ship. This analysis defined the missions that existing ships perform, the associated platform characteristics and the performance associated with the missions, the equipment required to conduct the missions, and the resulting ship characteristics and performance. 3.1.2 General Missions Requirement A mission analysis is a very important part of the design process for new OPVs and SLCs, particularly where a requirement-based (also referred to as requirement-driven) design process is being used. The success of any requirement-based mission analysis depends on the accurate definition of mission requirements that are determined by its operations, tasks and capabilities. Missions and operations are closely related, and often interrelated, when defining the same set of tasks to be carried out. Whereas a mission defines high-level goals determined by actual threats or undesirable situations, an operation is defined by a specific supporting, pre-defined goal. Operations, therefore, are the “toolbox” of armed forces or coast guards. This “toolbox” is to plan and organize the execution of a mission by dividing the job to be done into pre-defined and well-trained parts (Figure 3.1-1).

TASK

OPERATION

TASK

FUNCTION

CAPABILITY

FUNCTION

CAPABILITY

CAPABILITY

MISSION

OPERATION

MISSION MISSION

Figure 3.1-1. Hierarchy of Missions, Operations, Tasks, Functions and Capabilities

3.1.2.1 Small Ships: Displacement vs. Capabilities This Working Paper has been developed for both OPVs and SLCs. Both naval ship types, compared to frigates, are defined as “small ships” varying from 600 tonnes to 2000 tonnes. However, it is the limitation of a ship’s capability rather than its displacement that provides a more adequate



8

discriminator. Therefore, a small displacement could be the result of limited capabilities but not necessarily vice versa. The frigate, varying in displacement from 3000 tonnes to 5000 tonnes, remains an important point of reference among navies because it represents the smallest combatant that can conduct extended blue-water missions in a high-threat environment. It is, as a result of these capabilities, also a relatively sophisticated and expensive platform. The missions of OPVs and SLCs, like Corvettes and Fast Attack Craft, mostly involve regional operations, as these ships have limited endurance, range and seakeeping qualities. Additionally, their combat suite has a limited fighting capacity with respect to certain threats. Nonetheless, these platforms can prove extremely useful when supporting or conducting Power Projection missions, especially with respect to littoral operations. The OPV is specifically designed for patrolling the waters of an Exclusive Economic Zone (EEZ) and, therefore, specializes in conducting constabulary operations, which is its primary mission. Often, humanitarian and disaster relief operations are tasks also performed by these types of vessels. As these operations are executed in a low-threat environment, these vessels are generally lightly armed (a medium-sized gun). Boarding capabilities are essential to their operations, and these vessels are often equipped with one or two small fast boats. The difference between a Frigate, OPV and Corvette, as defined by the spectrum of their military employment, is presented in the graph in Figure 3.1-2a. A similar relationship can be derived by comparing the military employment and the sustainability of these different types of ships (see Figure 3.1-2b).

Functional spectrum

Incr

easi

ng

vio

len

ce


CorvetteFrigate

Military Power

Military Control

Military Patrol

Military Aid

Figure 3.1-2a. Military Employment versus Functional Spectrum

Sustainability spectrum

OPV

Corvette Frigate

Military

Power

Military Control

Military Patrol

Military Aid

Incr

easi

ng v

iole

nce

Figure 3.1-2b. Military Employment versus Sustainability Spectrum


NATO/PfP UNCLASSIFIED 9

3.1.2.2 Naval Operations Template for SSD Naval operations can be categorized according to four operational clusters: Military Aid, Military Patrol, Military Control and Military Power. Military Aid refers to all benign operations such as humanitarian assistance and disaster relief operations. Military Patrol refers to all law enforcement or constabulary operations. Military Control refers to all naval Sea Control operations. Military Power refers to all Power Projection operations. Both Military Control and Military Power clusters are related to operations often conducted in a medium or high-threat environment. They are, therefore, operations typically conducted by SLCs. The OPV is specifically designed for conducting Military Patrol operations, which is its primary role. Often, OPVs have built-in capabilities to conduct humanitarian and disaster relief operations. As an alternative, SLCs can also be used to conduct Military Aid and Military Patrol. These operations, however, are often defined as secondary missions. A similar cluster, often used when defining secondary missions related to littoral combatants, is “Peace Operations” or “Operations other than war”. This cluster is the NATO equivalent of “Non-Article 5 Crisis Response Operations” (NA5CRO) and not only refers to Military Aid and Military Patrol operations, but also includes Military Control (or Sea Control) insofar as these are limited to “Peace Support Operations” as defined by the UN and implemented by NATO. As cost-effectiveness becomes more and more an issue in naval ship design, there is a tendency to design multi-mission SLCs. To prevent the costs of SLCs from rising, modularization is used as an alternative. New OPVs are often equipped with a helicopter deck and hangar to enhance their patrol capabilities. Some nations include space and weight margins for future weapons upgrades with a view to using these ships for expeditionary Peace Support operations, or the equivalent of low threat Sea Control operations. From these developments, as visualized in Figure 3.1-3, it can be concluded that the overlap between OPVs and SLCs becomes more and more profound as far as operations are concerned.





War Operations

Peace Operations

Peace SupportOther Operations and Tasks

Small Surface Combatant (Corvette)


Primary Operations Secondary Operations

Naval Operations Template

Figure 3.1-3. Small Ship Design Operations Template versus OPVs and SLCs

This trend supports the possible use of a general template for Small Ship Design (SSD), defining missions to be carried out by both SLCs and OPVs. Based on the same four operational clusters, a template has been defined which summarizes all naval operations to be conducted by both types of ships. This template is shown in Figure 3.1-4 and can be used as a “toolbox” for mission analysis purposes.



Protect High Value Units

Gathering Information

Embargoes& Sanctions

Protect Sea Lines of Communications

Amphibious ops

Neutralise Naval Forces

Air Campaign

Land Campaign


Disaster Relief

Non CombatantEvacuation Ops

Humanitarian Operations

Search & Rescue (SAR)




Maritime Security

Safety ofNavigation at Sea

Border Control

EnvironmentalProtection

Support Operations

Naval Logistic Support

Sea Lift

Figure 3.1-4. Small Ship Design Operations Template Generic naval operations, as shown in this template, cover a cluster of operations based on mission similarity. To complete this naval operations template, a separate cluster, normally not conducted by littoral combatants, is added for conducting mission Support Operations . Within the context of this template, these operations concern Naval Logistic Support and Sealift. Naval Logistic Support, in general, extends the function of naval operations to providing spares, maintenance, re-supply of consumables and manpower “at sea”. Sealift operations are considered to be transport operations conducted to deploy, reinforce and re-supply expeditionary land forces. Both operations mainly concern the support of Military Control and Military Power clusters. 3.1.2.3 Small Ship Design Operations Template To have a better understanding of the naval operations mentioned in the template, each cluster of operations is now defined in more detail.

a. Military Aid (Benign Operations) Disaster Relief Supports efforts to relieve or minimize the results of natural or manmade disasters that might present a serious threat to life or can result in great damage to, or loss of, nature or property. Humanitarian Relief Supplements or complements the efforts of the responsible authorities to relieve or reduce the results of natural or manmade disasters or other endemic conditions that might present a serious threat to human life or result in great damage to, or loss of, property. Non-Combatant Evacuation Operations (NEO) Supports the safe and quick removal of civilian non-combatants from an area where they are being, or may be, threatened. Search and Rescue (SAR)



The search for and rescue of personnel in distress, on land or at sea, by means of aircraft, surface craft and submarines, specialized rescue teams and equipment.

b. Military Patrol (Constabulary Operations)

Maritime Security • Combating Terrorism:

- Antiterrorism: the protection of individuals and properties at sea to reduce vulnerability for terrorist acts.

- Counter terrorism: offensive measures taken to prevent, deter and respond to terrorism. • Anti-Piracy: the protection of individuals and properties at sea to reduce their vulnerability to

acts of piracy. • Aid/Support to Civil Authorities: provides legally authorized military assistance to civil

communities or authorities to counter civil disturbance (riots, group acts etc.) and quarantine operations.

Safety of Navigation at Sea • Support of vessel safety inspections. • Support of maritime traffic control.

Border Control • Enforce drug interdiction. • Enforce smuggling interdiction. • Prevention of illegal immigration.

Environmental Control • Marine Pollution Enforcement and Response: responds to hazardous material releases,

restoring contaminated land and water and conserving national natural and cultural resources.

• Enforce adherence to legislation on protection of living marine resources (fishing policing).

c. Military Control (Sea Control Operations)

Information Gathering • Support of Intelligence Gathering: proactive collection of information to produce useful

predictive intelligence to be disseminated to those who need to know. • Reconnaissance, Surveillance and Target Acquisition: systematic observation of areas,

places, persons, objects and targets in order to monitor change or movement of military significance, i.e. to support military operations relevant to strategic, operational and tactical information related to the following areas: - Indications and warning - Planning and employment - Assessment

Protect Sea Lines of Communications (SLOC) Ensure control and dominance of sea routes that connect an operating military force, including their supplies and reinforcements, with their bases of operations by conducting: • Anti Submarine Warfare (ASW) • Anti Surface Warfare (ASuW) • Anti Air Warfare (AAW) • Mine Warfare (MW):

- Mine Laying: to establish and maintain control of essential sea areas through the use of naval mines to inflict damage on enemy shipping, submarines, and/or to hinder, disrupt and prevent enemy sea operations.



- Mine Counter Measures (MCM): offensive and defensive operations for countering a mine threat, including the prevention of enemy mine-laying.

Protection of High Value Units • Protection of naval logistic support to forward-deployed battle forces. • Force Protection: conserving the fighting potential of the deployed force by countering the

threat (ASW, ASuW, and AAW). • Protection of Extraction Force.

Embargoes & Sanctions • Blockades: to isolate a place, especially a port, harbor or part of a coast to prevent enemy

forces from entry or exit. • MIO: the enforcement of sanctions that employ coercive measures to interdict the movement

of certain types of designated items into or out of a nation or specified area. (Military objective is to establish a selective barrier).

• UN economic sanction enforcement. • Peace Support Operations:

- Peacekeeping: monitor and facilitate implementation of an agreement (cease-fire, truce, etc.).

- Peace Enforcement: application of military force, or threat of its use, to compel compliance with resolutions or sanctions designed to maintain or restore peace and order (intervention, forcible separations of belligerents, establishment and supervision of exclusion zones).

d. Military Power (Power Projection Operations)

Amphibious Operations To establish an area of operations for power projection ashore and support of amphibious operations: • Establish & protect Sea Lines of Communications. • Provide Naval Surface Fire Support (NSFS) such as gunfire. • Conduct beach survey, Rapid Environmental Assessment (REA).

Neutralize Naval Forces • Specific targeting of enemy naval forces to ensure:

- protection of own force. - open and protected sea lines of communications to and from the (joint) operation area by

conducting AAW, ASuW and ASW. • Destruction of enemy bases/infrastructure (to destroy or neutralize the enemy’s ability to

control and support their naval forces).

Air Campaign / Land Campaign (JTF campaign) • Provide Naval Surface Fire Support (NSFS) gunfire strike. • Combat Search And Rescue (CSAR).

3.1.3 Tasks Table 3.1-1 lists the tasks performed by OPVs and SLCs, respectively. This table was based on a comprehensive review of existing ships. As shown in this table, SLCs primarily perform military control and power tasks and inherently have a secondary capability to perform military patrol and aid tasks, while OPVs are primarily designed to perform military patrol and military aid tasks and sometimes have a very limited secondary military control task capability.



Table 3.1-1

OPVs vs. SLCs – Tasks

Tasks OPV SLC

Alien Migrant Interdiction Primary Secondary

Port Security Primary Secondary

Drug Interdiction Primary Secondary

Environmental Defense Primary None

Foreign Vessel Inspection Primary Secondary

Law Enforcement Primary Secondary

Maritime Resources Enforcement Primary Secondary

Maritime Intercept Primary Secondary

Maritime Pollution Enforcement & Response Primary Secondary

Search & Rescue Primary Secondary

ASuW Sometimes Limited Yes

AAW Sometimes Limited

Self Defense

Self Defense,

sometimes limited

ASW None Sometimes

Special Forces Support None Sometimes

Land Attack None Sometimes

Mine Warfare Sometimes Limited Sometimes

The tasks that existing SLCs can perform depends on ship size. As shown in Figure 3.1-5, which is based on representative existing SLCs, it requires about 150 tonnes of displacement to mount a battery of anti-ship missiles plus a point defense system. In this case, a point defense system is considered a small caliber gun mount, as well as limited capability C4ISR systems required to conduct the ASuW mission. At about 250 tonnes, it becomes feasible to add an intermediate caliber gun mount of up to 76mm in size, thereby improving ASuW effectiveness. At a displacement of 500 tonnes, an ASuW small littoral combatant can carry more guns or anti-ship missiles, mount more effective point defense systems, and/or support a helicopter, embark a limited ASW suite, or mount davits for special forces boats, but not simultaneously. A 750-tonne small littoral combatant can mount a lightweight medium caliber gun mount of up to 127mm, but little else. An otherwise austere 1300-tonne SLC can simultaneously perform significant ASuW, AAW and ASW multi-mission tasks. A similarly austere 1800-tonne SLC can perform more effective multi-mission tasks, including mounting a larger number of land attack missiles and/or providing limited area air defense capability. Consequently, a small littoral combatant is not necessarily developed to perform only defensive tasks, nor is it necessarily limited to the types of tasks it can perform. But these ships generally lack the sustainability required for long deployments and the seakeeping characteristics necessary for the open ocean operations needed for power projection. However, because they generally operate within the range of land-based aircraft and anti-ship missiles, the threat density they can face may be relatively high.



0

500

1000

1500

2000

ASuWSingle

Mission

LimitedMulti-

Mission

ExtensiveMulti-Mission

Dis

plac

emen

t, T

.

Figure 3.1-5. SLC – Task Capability versus Size

By comparison to SLCs, the size of OPVs has substantially less impact on their task capability. Small, short OPVs, with a displacement of less than 1,000 tonnes and a length of less than 80m, can support stern launched small boats and a helicopter landing deck, but will be too short to also incorporate a hangar. However, larger, longer OPVs of about 2,000 tonnes, with a waterline length of about 80m or greater, will be able to incorporate a helicopter hangar. Additional hull length also provides somewhat better seakeeping and provides the internal space needed to increase sustainability, both of which are important for OPV task fulfillment. 3.1.4 Task-Related Characteristics The task-related characteristics and performance of OPVs and SLCs are compared in Table 3.1-2. As compared to SLCs of comparable displacement, OPVs generally are much slower, but have greater endurance. Offshore patrol vessels tend to patrol on-station in isolation at their most economic speed. SLCs tend to operate from secure bases in concert with task forces and cruise at higher speed. Virtually all OPVs return to port to replenish or refuel, whereas some SLCs can replenish and refuel at sea. Because they go in harms way, the survivability and damage control features of SLCs are designed to withstand combat attack, whereas OPVs generally follow modified commercial practice. Modern SLCs also have minimal signatures, whereas many OPVs have unconstrained signatures.



Table 3.1-2

OPVs vs. SLCs – Task Related Characteristics

Item OPV SLC

Speed 18-22 Knots 30+ Knots

Endurance 20-30 Days 5-10 Days

Speed for Endurance Most Economical 16-20 Knots

Replenish/Refuel at Sea No Yes

Survi vability/Damage Control: Commercial Practice

Naval Practice

- shock protection None Yes

- blast protection None Sometimes Limited

- fragment protection None Sometimes Limited

- NBC protection Sometimes citadel and washdown

Yes

- firefighting Commercial Practice

Naval Practice

- subdivision and stability Commercial Practice

Naval Practice

Signature control: None Naval Practice

- radar None Yes

- IR None Sometimes

- E/O None Sometimes

- acoustic None Sometimes

- magnetic None Sometimes

- wake None Sometimes

3.1.5 Task-Related Equipment The task-related equipment of existing OPVs and SLCs has been provided to fulfill the task-related requirements listed in Table 3.1-1. As shown in Table 3.1-3, SLCs accordingly mount a comprehensive suite of sensors and weapons, whereas OPVs do not. By comparison, OPVs sometimes employ specialized boats and boat recovery/launch systems and other unique systems required for military aid and patrol missions.



Table 3.1-3

OPVs vs. SLCs – Task Related Equipment

Item OPV SLC Specialized Boats and Recovery/Launch Systems

Yes No

Fuel Recovery Systems Sometimes No Firefighting Monitor Sometimes No Cargo Hold/Modular Stowage Area Sometimes No Aviation Facilities: Yes Sometimes

- Armed Helicopters w/Shipboard Magazine

No Sometimes

- Landing Deck Aids and Retrieval System

Yes Sometimes

- Hangar Sometimes Sometimes - Logistics Support Sometimes Sometimes - Number 1 or 2 Maximum 1 - C3I Limited Extensive

C4ISR Limited, COTS Extensive, Major Combatant Standards with multiple data links

Sensors: Limited Extensive - Stabilized E/O Yes Yes - Surface Search Radars 2 Commercial 1 low probability intercept 1

commercial - Air Search Radar None Sometimes 2D Volumetric 3D

w/High Data Rate and Subclutter Visibility

- Gun/Missile Fire Control Local Control or Limited for Gun

EO and Radar, sometimes multiple channels

- EW None Passive, sometimes active, sometimes SIGINT

- SONAR None Sometimes Bow or Keel Hull Mounted, VDS and Towed Array

Decoy Launchers None Radar, sometimes IR & E/O, sometimes torpedo

Weapons: - Guns Sometimes one low

performance Generally one primary, 40-

127mm two or more secondary, 30mm or less

- Point Defense Anti-Missile Systems

None Gun and/or Missile capable of intercepting multiple threats

- Anti-Air Missiles None Manportable, trainable canister, or vertical launched, current range out to 10km, increasing to 30 km

- Anti-Ship Missiles None Yes, usually 8 canister launched evolving capability with guided projectiles & missiles

- Land Attack Systems None Evolving capability with guided projectiles and missiles

- ASW Torpedoes/Weapons None Sometimes Special Forces Support None Sometimes special boats with

launch and recovery systems plus berthing



3.1.6 Ship Characteristics The resulting ship characteristics which typify OPVs and SLCs are summarized in Table 3.1-4. Because they are generally slower, OPV hulls tend to be fuller than those of SLCs, with a higher displacement-to-length ratio. Slower OPVs also have relatively less installed propulsive power. Because of the differences in mission equipment and lack of dedicated damage control teams, OPVs can have smaller crews, particularly because they are often comprised of professional mariners in lieu of high turnover, less experienced military personnel. High-speed SLCs have hull, mechanical and electrical equipment that is designed to meet lightweight naval standards. They have high payload-to-area fractions and payload-to-weight fractions, austere habitability, and extensive redundancy and separation for high availability and combat survivability. The hulls of SLCs are also designed to meet demanding naval intact and damaged stability standards. Conversely, OPV propulsion plants often have specialized propulsion systems for low-speed loiter operations. Most significant is the obvious difference in the ratio of payload-to-total program cost. In SLCs, the proportionate allocation of program cost to the payload should be very high because of the relatively high ratio of combat system payload weight to light ship weight, whereas in OPVs this ratio should be relatively lower. Similarly, the overall cost-per-tonne of SLCs should be considerably higher than that for OPVs. Design studies were developed to substantiate these differences (see section 3.2).

Table 3.1-4

OPVs vs. SLCs – Ship Characteristics

Item OPV SLC

Displacement to Length Ratio (Displ/0.1L3) Medium Low

SHP to Displacement Ratio Low to medium High

Crew type Often mariners Naval

Crew size Low High

Hull structure Commercial Naval

Habitability Excellent Austere

Construction and equipment standards Commercial Naval (increasing COTS)

Loiter propulsion/thrust Yes No

Payload area and weight fractions Low High

Stability 2 compartment commercial

3 compartment naval

Redundancy and separation Limited to commercial practice

Extensive, naval practice

Ratio of payload to total program cost Low Very high

3.1.7 Summary Small littoral combatants and OPVs often are about the same size and operate in similar environments, but they are otherwise very different. Small littoral combatant, as used herein, means ships designed for operation in a dense, high threat, combat environment within the reach of ground-based attack aircraft and shore-based anti-ship missiles. Currently, this refers to ships normally operating out to about 250



nautical miles offshore. Water depth, sea conditions and geographic constraints will all be scenario/location dependant. Small is often varyingly defined in terms of length, displacement, numbers of crew or cost. For purposes of this Working Paper, the year 2003 follow-ship acquisition cost, defined as a shipyard cost limit of less than 325 million U.S. dollars, is used as the upper limit. This limit represents about half the cost of a state-of-the-art multi-role frigate. Small littoral combatants are designed to conduct warfighting tasks, whereas offshore patrol vessels are designed to enforce maritime law and ensure safety. Small littoral combatants are far more comprehensively equipped with sensors, C4ISR systems and weapons. Small littoral combatants can vary from limited single-mission ships to larger multi-mission ships that can conduct offensive or defensive missions for all types of naval tasks. Because of their limited sustainability, SLCs generally operate from fixed shore bases or forward-based depot ships. They generally depart, conduct an operation, and return without replenishment. Compared to OPVs, they generally have much higher speed, follow naval design practices, have improved survivability, and have much lower signatures. The mission requirements for SLCs often have relatively larger naval vice commercial mariner crews. 3.2 Offshore Patrol Vessels and Small Littoral Combatants 3.2.1 Introduction In order to illustrate the differences between OPVs and SLCs, and to show the impact of displacement on capability and cost, four notional point designs were developed: 600-tonne and 2000-tonne OPVs and SLCs, respectively. Trade-off studies and comparative acquisition cost estimates were developed for each point design. The tasks, task-related characteristics and task-related equipment, which were discussed in section 3.1, were used to generate performance requirements applicable to each of these four point designs (Table 3.2-1). The performance requirements and mission equipment selected for these four designs were based on those for existing OPVs and SLCs varying in size from about 600 tonnes to 2000 tonnes. These requirements and lists of mission equipment were arbitrarily selected. No attempt has been made to optimize the choice of requirements and equipment relative to achieving the objective displacements. All task-related equipment reflects state-of-the-art respresentative systems. The number of accommodations were estimated based on the crewing levels of comparable existing ships.

Table 3.2-1

Design Study Performance Requirements

Characteristic 600 OPV 2000 OPV 600 SLC 2000 SLC Tasks: Alien Migrant Interdiction Primary Primary Secondary Secondary Port Security Primary Primary Secondary Secondary Drug Interdiction Primary Primary Secondary Secondary Environmental Defense Secondary,

w/Modular Eqp. Primary None None

Foreign Vessel Inspection

Primary Primary Secondary Secondary

Law Enforcement Primary Primary Secondary Secondary Maritime Resources Enforcement

Primary Primary Secondary Secondary

Maritime Intercept Primary Primary Secondary Secondary Maritime Pollution Enforcement & Response

Primary, w/Modular Eqp

Primary, w/Modular Eqp

None None

Search & Rescue Primary Primary Secondary Secondary ASUW None None Yes Yes



Characteristic 600 OPV 2000 OPV 600 SLC 2000 SLC AAW None None Self Defense Ships In

Company ASW None None Yes, w/Modular

Systems Yes

Special Forces Support None None Yes, w/Modular Eqp

Yes, w/Modular Eqp

Land Attack None None Yes, w/Modular Systems

Yes

Mine Warfare None None None Self Defense Aviation Capability Landing Deck Landing Deck &

Hangar Landing Dk, Also Used for Modular Eqp

Landing Deck & Hangar

Task Related Characteristics: Trial Speed 21 Knots 21 Knots 33 Knots 33 Knots Endurance w/o

Support 7 Days 30 Days 7 Days 20 Days

Range 3000N.Mi @ 16Knots

7000N.Mi @ 12Knots

2400N.Mi @ 15Knots

4500N.Mi @ 16Knots

Logistical Self Sufficiency

No Yes No Yes

VERTREP No Yes No Yes RAS No No No Yes FAS Floating Hose Yes Floating Hose Yes

Survivability/Damage Control: - Shock Protection No No Limited Limited - Blast Protection No No Limited Limited - Fragment Protection No No No No - NBC Protection Yes Yes Yes Yes - Firefighting Commercial

Practice Commercial Practice

Naval Practice Naval Practice

- Subdivision and Stability

Commercial Practice, Two Compartment Standard

Commercial Practice, Two Compartment Standard


- Damage Control Commercial Practice, plus Two D.C. Lkrs.

Commercial Practice, plus Two D.C. Lkrs.


- Redundancy & Separation

Commercial Practice

Commercial Practice


Signature Control: - Radar No No Yes Yes - IR No No Yes Yes - E/O No No Yes Yes - Acoustic No No No Yes - Magnetic No No Yes Yes - Wake No No Limited Yes

Task Related Equipment: Boats 8m Boat in Stern

Well 10m Boat in

Stern Well Modular Davits

for Assault Craft plus small RHIB/Davit

Modular Davits for Assault Craft plus medium RHIB/Davit



Characteristic 600 OPV 2000 OPV 600 SLC 2000 SLC Fuel Recovery Systems

Modular Modular No No

Firefighting Monitor Yes Yes No No Modular Area Landing Deck Hangar, Landing

Deck, & Cargo Hold

Landing Deck, Hangar and Weatherdeck

Landing Deck, Hangar and Weatherdeck

Aviation Facilities: - Landing Deck Yes Yes Yes Yes - Hangar No Yes UAV/Small Helo Yes - Landing Aids Harpoon Lightweight

RAST Harpoon Lightweight

RAST - Shops/Stores Very Limited Yes Very Limited Yes - C3I Very Limited Limited Limited Extensive - Aviation Magazine No Limited No Yes - JP-5 (0.6 LT/Flight

Hr) 30 Flt. Hrs. 150 Flt. Hrs. 30 Flt. Hrs. 90 Flt. Hrs.

Sensors: - Surface Search

Radar 1 Navigation, 1 Air/Surf Search

1 Navigation, 1 Search

1 Navigation, 1 TWS Search

1 Navigation, 1 TWS Search

- Air Search Radar None Short Range 2D Alert 3D Alert 3D, Volumetric 2D

- Gun/Missile FC Systems

1 E/O 1E/O 1 Radar 1 E/O

2 Radar 2 E/O

- EW Simple Passive Simple Passive Passive/Active, Modular SIGINT/ELINT

Passive/Active, SIGINT/ELINT

- Sonar No No Modular VDS & Towed Array

Bow Mounted, VDS & Towed Array

- Decoy Launchers No No Fixed, plus 1 Trainable

3 Trainable, Torp Def. System

Weapons: - Guns 1x30mm 1x30mm 1x57mm

2x25mm 1x57mm 2x30mm

- Point Defense Systems

None None RAM 2xRAM

- Anti-Air Missiles None None None 32xESSM in VLS

- Anti-Ship Missiles None None 8 Cannister Launched SSM

8 Cannister Launched SSM

- Land Attack Missiles None None In Lieu of SSM 32 Polyphene in VLS

- ASW Weapons None None In Lieu of Helo/SSM

2 ASW T.T. + 6 Torpedoes

- Helicopter 1-Seven Tonne 1-Seven Tonne 2 VUAV or 1-Seven Tonne

2 VUAV or 1-Seven Tonne

C4ISR: - CIC 2 Consoles

Adjacent to Bridge

4 Consoles + 1 LSD Adjacent to Bridge

CIC, 8 Consoles + 1 LSD

14 Consoles + 3 LSD CIC in Hull



The objective of the point designs is to illustrate: 1) the differences between OPVs and SLCs, and 2) the impact of displacement on capability, performance and cost. Consequently, each of the four point designs reflects the use of state-of-the-art hull, mechanical and electrical (HM&E) systems, typical monohull hull forms, standard international design criteria and practices, and conventional crewing. The four point designs were developed with the assistance of a ship design synthesis computer program. This synthesis program uses interpolation to determine the one combination of waterline beam and hull draft that will provide both the specified values of metacentric height-to-beam ratio and cruising range. Each point design was developed using a pre-selected, non-dimensional parent hull form. Parent hull form data, includes non-dimensional hull offsets (used to calculate the available deck area), curves of form data (used to calculate the metacentric heights), and hull resistance data (which permits the determination of speed and range). The computer synthesis program has the inherent flexibility to allow the operator to adjust all the pre-existing parametric equations used to determine weights and associated centers of gravity, required deck area, and ship service electrical loads. All the inputs specifying the design criteria and practices to be employed by the point designs can also be modified. The design process used to develop the point designs follows:

a) Based on the performance requirements, deck area requirements were developed.

b) The parent hull form was selected.

c) A baseline propulsion plant and machinery box and a ship’s service electric plant were determined.

d) A baseline inboard profile was developed which had appropriate tankage volume, available deck area, a feasible machinery box, appropriate subdivision, and a practical topside arrangement.

e) Computer input was prepared by adjusting all parametric equations, criteria and practices as appropriate for each point design study.

f) Based on the results of the initial computer analyses:

• The superstructure arrangement was adjusted to balance deck area, i.e. to ensure that available is approximately equal to the required deck area.

• Diesel engine power was adjusted to provide the specified speed. For these comparative studies, all diesel engines and all SSDG sets were assumed to be available at infinitely variable power levels.

g) The process was reiterated as required. The results were point designs with:

• GMv/BDWL = 0.085 at all loading conditions • Range as specified • Speed is approximately equal to the required • Available is approximately equal to the Required Deck Area • Available is approximately equal to the Required Tank Volume

The point designs were developed to reflect representative international design criteria and practices. The design and service life margins used for the point designs are provided in Table 3.2-2. Range was calculated based on the resistance of the hull at the mean trial loading condition. The range calculation included both the detail design ships service electric load and detail design resistance (EHP) margins, as well as a 5% tail pipe allowance for unburnable fuel. Trial speed was also calculated at the mean trial displacement at 100% of available power with no engine margin. The definition of trial speed includes the detail design resistance (EHP) margin plus a speed margin of 0.25 knots. The synthesis program employs the Taylor-Gertler standard series to calculate the resistance of conventional monohulls. At



each specified speed, it separately calculates frictional, residual, appendage and air drag. The calculation for each speed also includes the specified overall resistance margin and estimated propulsive coefficients in order to calculate SHP and an allowance for reduction gear, coupling and bearing losses used to determine required engine BHP. Based on the parent hull form, an inputted inferiority/superiority, i.e. “worm curve”, is used to adjust the standard series residual resistance at all Froude Numbers. Frictional resistance is calculated using the 1957 International Towing Tank Conference (I.T.T.C.) formula.

Table 3.2-2

Design Study Margins

• Detail Design and Construction

- 8% Light Ship Displacement

- 4% Light Ship KG

- 15 % Ship Service KW Load

- 8% Total EHP

• Service Life

- 10% Light Ship Displacement

- 0.3 m Light Ship KG

- 15% Ship Service KW load

- 5% Net Arrangeable Deck Area

Because the synthesis program is inherently flexible, each weight and vertical center of gravity (KG) equation was modified to reflect the specific requirements for each point design and/or the inboard profile and general arrangements. For example, the vertical centroids of fuel oil, potable water, JP-5 and other loads reflect the tank and storeroom arrangement developed for each point design, while the required deck area was based on a list of individual spaces developed by the operator. Prior experience with this synthesis model shows that the overall result has a high degree of fidelity and accuracy. The computer program output is, therefore, considered as accurate as an enhanced manual conceptual design. It is considered suitable for evolution into a more detailed preliminary or contract design without further design evolution.



3.2.2 600-Tonne Offshore Patrol Vessel The inboard profile and overall characteristics of the 600-tonne OPV point design are summarized in Figure 3.2-1. The ship has a sloped stern well for a 9m RHIB, with the helicopter landing deck located above the 01 Level. The landing deck is sized for a SH-60 helicopter. There is no hangar.

LENGTH, LBP 60.9M LIGHTSHIP DISPLACEMENT 547 Tonnes

BEAM AT DWL 7.8M FULL LOAD DISPLACEMENT 682 Tonnes

DRAFT, FULL LOAD MIDSHIPS 3.1M ARRANGEABLE DECK AREA 665M²

AVERAGE HULL DEPTH 5.6M PROPULSION PLANT: Twin Screw Diesel

2 x 2611 kw Diesel EnginesTRIAL SPEED 20.9 Knots 1.69m 600 RPM CPP Propellers

RANGE 3,000 N.Mi@ ACCOMMODATIONS:16 Knots [email protected]²/ACCOM

ENDURANCE 7 Days SHIP SERVICE ELECTRICAL POWER:Two 300kW SSDG SetsOne 160 kW Emergency DG Set

/ASR

Figure 3.2-1. 600-Tonne OPV Inboard Profile & Summary of Ship Characteristics

The 600-tonne OPV hull has a short forecastle that extends aft to frame 23.02. All structure is based on the use of commercial classification society rules. The Main Deck superstructure, which extends aft of frame 23.02, is constructed of steel. The superstructure, stack and mast above the 01 Level are all constructed of aluminum. Required deck area is provided in Table 3.2-3. Available deck area is only 0.2% greater than the required area. The parent underwater hull form is based on that used by typical international fast attack craft. The baseline hull form incorporates above waterline hull flare and has been adjusted to reflect the use of a prismatic coefficient (CP) of 0.65, a maximum section area coefficient (CX) of 0.675, and a stern flap. The block coefficient (CB=CP*CX) were increased in order to reduce the draft and provide adequate freeboard from the design waterline up to the Main Deck aft. Speed and power calculations are based on the use of a correlation allowance of 0.30 x 10-3. Synthesis program input and output are provided in Appendix 9.1.



Table 3.2-3

600-Tonne OPV, Required Deck Area

Category Area, m² Task-Related: Bridge And Adjacent Command Area 49.26 Communications Room 11.15 Electrical Equipment Room 9.29 30mm Ready Service Magazine 9.29 Magazine/Small Arms Locker 18.59 Aviation Storage Locker 9.29 JP-5 Pump Room 9.29 Sub Total 116.17Personnel: 30 Accommodations @ 9.63m²/accom 288.75Administration: Ships Office 9.29Propulsion: Stack 22.30 Air Intake & Exhausts, MnDk & 01 Level 20.45 Engineering Control Room 16.73 Sub Total 59.48Auxiliary Spaces: Anchor Handing 7.34 Emergency Generator Room 13.01 Thruster Equipment Room 11.71 HVAC (3.5% Available Area) 21.10 Sub Total 53.16Maintenance: Shop 7.44 2 DC Lockers 5.58 Sub Total 13.02 Stowage: 23.23Access: 10% Gross Area 66.45Unassigned:

5% of net area, 493.12, where: 493.12 = Gross Area Less Access, HVAC, Stack & Air Intakes 24.63

Total Required Area 654.18



3.2.3 2000-Tonne Offshore Patrol Vessel The inboard profile and overall characteristics of the 2000-tonne OPV point design are summarized in Figure 3.2-2. In order to minimize ship length and displacement, an expandable hangar is used. The expandable hangar is located just aft of the emergency generator room, which is located on the 01 Level at the centerline between the port and starboard intakes and exhausts. A small cargo hold is provided forward on the Main Deck, with an access hatch located above on the 01 Level. The 30mm gun mount is located forward on an elevated platform to provide all around short-range coverage. The anchor handling and mooring systems are located in a large non-tight area within the forecastle, where they are protected from the environment. The helicopter landing deck extends aft over a centerline sloping boat well, which is provided for a 10m RHIB. The forecastle extends back to frame 57.92. The depth of the hull is based on the required height of the engine room over the single bottom structure, plus the depth of the Second and Main Decks.

LENGTH, LBP 76.5M LIGHTSHIP DISPLACEMENT 1,860 Tonnes

BEAM AT DWL 13.8M FULL LOAD DISPLACEMENT 2,320 Tonnes

DRAFT, FULL LOAD MIDSHIPS 4.5M ARRANGEABLE DECK AREA 2,260M²

AVERAGE HULL DEPTH 10.9M PROPULSION PLANT: Twin Screw DieselEach Shaft W/2 x 2,238 kW Diesels

TRIAL SPEED 20.2 Knots 3.03M 265 RPM CPP Propellers


ENDURANCE 30 Days SHIP SERVICE ELECTRICAL POWER:Two 1100kW SSDG SetsOne 375kW Emergency DG Set

Figure 3.2-2. 2000-Tonne OPV Inboard Profile & Summary of Ship Characteristics

Structure is based on the use of commercial classification society rules. The superstructure, expandable hangar, mast, stack and the 01 Level helicopter landing deck are all constructed of aluminum. The required deck area is provided in Table 3.2-4. Available deck area is 0.12% greater than required deck area. The main propulsion diesels and reduction gears are co-located within a single large engine room. Each shaft is powered by two diesel engines, thereby increasing the load factor on one engine when the ship is loitering at the most economical speed. An azimuthing thruster/propulsor is provided forward. It has been assumed that the thruster can be integrated into the propulsion plant and centrally controlled via joystick for low-speed operations and/or maneuvering.



Table 3.2-4

2000-Tonne OPV, Required Deck Area

Category Area, m² Task-Related: Bridge 48.98 Operations Center & Equipment Room 46.47 Communications Center & Equipment Room 25.09 Radar Equipment Room 11.15 Magazine & Small Arms Locker 28.81 Fixed Hangar 49.16 Helicopter Storeroom 11.15 Helicopter Shop/Office 16.73 JP5 Pump Room 8.36 Boat Handling on Second Deck 90.15 Sub Total 336.06 Personnel-Related: CO Suite 31.60 Exec S.R. + San. 22.30 5 Officer 2 Person S.R. + San. 144.98 4 CPO 2 Person S.R. + San. 102.60 17 Enlisted 4 Person S.R. + San. 436.06 Wardroom 16.73 CPO Mess/Lounge 9.29 Crews Mess 65.06 Crew Multi-Function Rm 11.15 Gym 9.29 Ships Store 5.58 Laundry 13.01 Baggage Rm 9.29 Galley & Pantry 34.76 Provisions & Stores 49.07 Medical Facility 16.73 Sub Total 983.09 Administration: Ships Office 13.94 Propulsion: Stacks 16.73 Uptakes/Intakes 27.88 Engineering Control Room 44.61 Total 89.22 Auxiliary Machinery: Anchor Handling & Mooring Forward 80.20 Auxiliary Machinery First Platform Level 29.55 Auxiliary Generator Room 43.68 HVAC (1,924 @ 0.05) 96.00 Total 249.43 Maintenance: 2 DC Lockers 18.59 Stowage: 6% of Total Area 135.69 Cargo Hold 41.82



Category Area, m² Total 177.51 Access: 12.5% of Total Area 282.90 Tankage Area: 30.02

Unassigned: 77.05 5% of net useable deck area, 1,540.52 x 0.05 Total Required Area 2,258.0sq.m

The parent hull form is based on the U.S. Coast Guard’s 270-ft medium endurance cutter, modified to incorporate improved hull flare forward, integral forward spray rails, and a transom that is reshaped to permit the centerline boat well to terminate below the waterline for safe boat launch and retrieval. Synthesis program input and output are provided in Appendix 9.2. 3.2.4 600-Tonne Small Littoral Combatant The inboard profile and overall characteristics of the 600-tonne SLC point design are summarized in Figure 3.2-3. The overall design and parent hull form are both based on existing fast attack craft of similar size. A conventional quadruple-shaft diesel propulsion plant was selected for this design. Two engine rooms were provided, located forward and aft of a small engineering control room, with the outboard engines and reduction gears located forward, and the inboard engines and reduction gears located aft. The ship has a SH-60 sized helicopter landing deck aft and an adjacent fixed hangar/multi-function space for a single small helicopter. In order to generate the required deck area, a full beam superstructure is provided along the Main Deck. The superstructure extends from outboard of the hangar to a point relatively far forward. The command spaces are tiered forward above the 01 Level. In order to minimize displacement, the length of the hull was foreshortened. Consequently, the forward intermediate caliber gun mount and bridge are located relatively far forward. Additional hull length would have permitted shifting them to a more desirable position relatively further aft, resulting in greater displacement. However, this was considered inconsistent with the objectives of this study, which was to generate a 600-tonne SLC. The lightweight steel hull and aluminum superstructure are designed to naval standards. In order to minimize hull weight, the internal hull platform level and bulkheads are constructed of aluminum. To minimize the radar cross-section, the hull has 12° of flare, with the superstructure employing 12° of tumblehome topside. Masking bulwarks are located outboard of the surface-to-surface canister-launched missiles. Provision has also been made for the weight and KG of the radar absorbing material that would be applied to external fittings and local radar reflectors. To minimize the ship’s thermal signature, the diesels exhaust below the waterline at high power levels, while the generator exhausts are screened. Special low-emission surface coatings are employed, along with a water washdown system used to cool the above waterline decks and superstructure. Table 3.2-5 provides the weight, KG, and electrical loads of the numerous payload systems mounted on the 600-tonne SLC. Table 3.2-6 provides the required deck area. The total required and available deck areas are in balance. Synthesis program input and output are provided in Appendix 9.3.



LENGTH, LBP 61M LIGHTSHIP DISPLACEMENT 590 Tonnes

BEAM AT DWL 8.7M FULL LOAD DISPLACEMENT 763 Tonnes

DRAFT, FULL LOAD MIDSHIPS 3.1M ARRANGEABLE DECK AREA 742M²

AVERAGE HULL DEPTH 6.4M PROPULSION PLANT: Quadruple Shaft Diesel

5470 kW Diesel Per ShaftTRIAL SPEED 35.5 Knots 1.96M 600 RPM Propellers


ENDURANCE 7 Days SHIP SERVICE ELECTRICAL POWER:Three 300kW SSDG Sets

Characteristics

Figure 3.2-3. 600-Tonne SLC Inboard Profile & Summary of Ship Characteristics



Table 3.2-5

600-Tonne SLC, Payload Characteristics

Item Wt, T. KG, m kW Group Four Payload Systems Navigation Radar, Antenna 0.07 14.02 -- Navigation Radar, Equipment 0.07 11.74 1.5 Surface Search Radar, Antenna 0.09 18.90 -- Surface Search Radar, Equipment 0.15 11.74 3.5 Alert Radar, Antenna 0.54 20.58 -- Alert Radar, Equipment 1.57 16.16 20.0 STIR, Antenna 1.97 16.16 -- STIR, Equipment 4.56 13.11 45.0 Mk 46 E/O System 0.12 14.63 3.0 SLQ 32V (3) Antenna 3.00 16.77 -- SLQ 32V (3) Equipment 6.00 13.41 15.0 Fixed Decoy Launcher 0.75 10.67 2.0 Deseaver Decoy Launcher 1.50 14.79 6.0 C4ISR Display & Decision System 5.64 5.03 12.0 External Communications System 4.75 8.54 8.0 Group 420 Navigation System 2.05 9.15 4.5 Group Seven – Armament 57mm Gun Mount 6.40 7.93 25.6 57mm Magazine Fittings 1.75 4.73 -- 2 x Typhoon Gun Mounts 1.35 9.45 10.0 1 x Mk 49 RAM Launcher 6.04 12.20 16.0 8 x Harpoon Launchers 11.37 10.52 6.0 Small Arms & 25mm Fittings 1.5 1.98 -- Aviation Loads Helicopter/VUAVs 7.0 7.32 -- Stores and Provisions 3.5 6.55 -- JP-5 14.21 1.84 -- Ammunition 57mm 5.27 4.73 -- 25mm Ready Service & Magazine 2.10 5.78 -- RAM 1.88 12.20 -- Harpoon 5.37 10.52 -- Small Arms 0.50 1.98 --



Table 3.2-6

600-Tonne SLC, Required Deck Area

Category Deck Area, m2 Task-Related CIC 43.31 CIC Equipment Room 12.17 Communications Room 11.15 Alert Radar Equipment Room 5.95 FC Radar Equipment Room 10.22 ECM Equipment Room 10.22 57mm Magazine 17.47 Hangar/Multifunction Room 55.30 Aviation Support Eqp Room 6.97 JP-5 Pump Room 6.97 Subtotal 179.74Personnel-Related 48 Accommodations @ 6.8m²/Accom 326.67Ship Control Bridge 26.86Propulsion ECR 28.62 Intakes 5.58 Subtotal 34.20Auxiliary Systems (Does Not Include HVAC Below Bridge) Mooring (includes Bosuns Strs) 7.90 HVAC Aft 9.29 HVAC Fwd 9.29 Subtotal 26.49Maintenance Two 2.8m2 D.C. Lockers 5.58Stowage Aft Fr 183.5 – 191 16.73 1st Pltf Fwd 11.06 Subtotal 27.79Access (10% Gross Area) 1st Pltf Aft 13.94 CIC 3.72 Living Area Fwd 8.64 Main Deck 41.64 01 Level 7.43 02 Level 3.72 Subtotal 79.09Unassigned 5% of net deck area, 542 x 0.05 27.14 Total Required Deck Area 733.55



3.2.5 2000-Tonne Small Littoral Combatant The inboard profile and overall characteristics of the 2000-tonne SLC point design are summarized in Figure 3.2-4. The overall design is based on that of the U.S.-developed SAAR V, modified to provide a continuous Second Deck. The additional deck level is required to support the relatively larger crew and more generous habitability standards provided for this design. A triple-screw CODAG propulsion plant is employed for this design, similar to that employed by numerous Soviet/Russian corvettes and small frigates. The triple-screw CODAG plant appears to be the lightest and simplest way of generating relatively high power while requiring minimum weight and machinery box volume. The location of weapons and sensors, and the tiering of the superstructure, largely follow the SAAR V design.

LENGTH, LBP 93.9M LIGHTSHIP DISPLACEMENT 1,964 Tonnes

BEAM AT DWL 13.2M FULL LOAD DISPLACEMENT 2,465 Tonnes

DRAFT, FULL LOAD MIDSHIPS 3.8M ARRANGEABLE DECK AREA 2,827M²

AVERAGE HULL DEPTH 9.1M PROPULSION PLANT: Triple Screw CODAGCenter: 23, 150kW GT, w/

TRIAL SPEED 31.7 Knots 4.33M 210 RPM CPP PROPOutbd: 6,210 kW Diesels, w/

3.28M 160 RPM CPP PROPS


ENDURANCE 20 Days SHIPS SERVICE ELECTRICAL POWER:Three 880kW SSDG Sets

Figure 3.2-4. 2000-Tonne SLC Inboard Profile & Summary of Ship Characteristics

The parent hull form is based on that used by the Italian Lupo/Maestrale class fast frigates, modified to incorporate more Vee-shaped forward sections, a small bow sonar dome, 12° of hull flare up to the Second Deck, and 12° of tumblehome above the Second Deck. The superstructure also incorporates 12° of tumblehome and shape to reduce the radar cross-section. The steel hull and aluminum superstructure are designed to naval standards. To minimize weight, the Second Deck, First Platform and hull bulkheads are all constructed of aluminum. The inner bottom and deep tank structure that directly supports the hull were assumed to be constructed of steel. Radar absorbing material and masking bulwarks are provided in order to reduce the RCS. The masking bulwarks are located above the 01 Level between the forward superstructure and the aft hangar. A prairie-masker system and relatively large diameter, low RPM propellers are employed to reduce the acoustic signature. Acoustic surface sheathing is provided to suppress transmittal of airborne noise in way of the soft-mounted main propulsion diesels and diesel SSDG sets in lieu of heavier and more volumetric double soft-mounted enclosures. To reduce the thermal signature, the uptakes are educted and shielded, and both low emissivity surface coatings and a water washdown system are provided.



Payload characteristics are provided in Tables 3.2-7 to 3.2-9 for electronics, weapons, aviation and ammunition, respectively. Table 3.2-10 provides the required deck area for payload-related spaces. Table 3.2-11 provides the overall required deck. The total required and available areas are in balance. Synthesis program input and output are provided in Appendix 9.4.

Table 3.2-7

2000-Tonne SLC, Electronics Payload

Item Wt, T. KG, m. Cruise kW Navigation Radar, Antenna 0.07 22.56 1.5 Navigation Radar, Equipment 0.07 15.85 -- Surface Search Radar, Antenna 0.09 22.56 3.5 Surface Search Radar, Equipment 0.15 15.85 -- 2D Volumetric Radar, Antenna 1.41 21.95 28.7 2D Volumetric Radar, Equipment 6.25 15.85 -- Alert 3D Radar, Antenna 0.54 24.39 20.0 Alert 3D Radar, Equipment 1.57 21.04 -- 2FC Radar Tracker/Illuminators, Antenna 3.94 18.29 90.0 2FC Radar Tracker/Illuminators, Equipment 9.12 15.85 -- 2 E/O Systems 0.24 20.27 6.0 EW System Antenna 3.00 18.60 15.0 EW System Equipment 6.00 21.65 -- Bow Mounted Sonar Transducer 3.00 -0.91 30.0 Bow Mounted Sonar Equipment 2.40 4.88 -- VDS & Towed Array 12.00 7.01 49.2 3 Decoy Launchers 4.50 18.50 18.0 Torpedo Defense System 14.50 1.83 19.75 C4ISR Display & Decision System 10.21 7.47 24.00 External Communications System 7.25 8.84 12.00 Group 420 Navigation 2.25 9.15 5.0

Table 3.2-8

2000-Tonne SLC, Weapons and Aviation Payload

Item Wt, T. KG, m Cruising kW Weapons

57mm Gun Mount 6.40 10.21 25 57mm Magazine Fittings 1.75 7.32 -- 2 x Mk46 30mm Gun Mounts 5.00 14.63 16 30mm Magazine Fittings 1.50 12.50 -- 2 x Mk49 RAM Launchers 12.08 14.94 32 2 x Mk41 VLS & Equipment 29.102 9.30 32 8 x Harpoon SSM Launchers 11.37 13.26 6 2 x Mk32 Torpedo Tubes 2.09 9.91 3 Helicopter/Torpedo Magazine Fittings 3.00 9.91 3 Small Arms Locker 2.50 4.42 --

Aviation Loads Helicopt ers 13.00 10.52 -- Spares Tools & Equipment 7.17 6.62 -- JP-5 52.92 1.52 --



Table 3.2-9

2000-Tonne SLC, Ammunition

Item Wt, T. KG, m 57mm 5.27 7.47 30mm Ready Service 0.82 14.63 30mm Magazine 2.68 12.50 RAM Fwd 1.88 13.41 RAM Aft 1.88 15.55 ESSMS 20.416 6.25 Polyphene 7.66 9.15 Harpoon 20.29 13.26 Mk46/50 Torpedoes 2.71 9.91 Helicopter Munitions 3.00 9.91 Small Arms 1.50 4.42

Table 3.2-10

2000-Tonne SLC, Payload-Related Area

Space Net Area, m2 CIC 94.05 Communications Room 16.73 Search Radar Equipment Room, Alert Radar 11.15 Search Radar Equipment Room, 2D Radar 14.87 FC Radar Equipment Rooms 2 @ 11.15 ea ECM Equipment Room 11.15 VDS Equipment Room 29.00 Sonar Equipment Room 22.30 Torpedo & Helicopter Magazine 26.77 57mm Magazine 13.94 30mm RS Rooms 2 @ 4.65 30mm/Small Arms Magazine 13.94 Mk41 VLS 6 levels @ 9.48m2/level Hangar 116.17 Helicopter Shop 12.08 Helicopter Office 12.08 Helicopter Storeroom 12.08 JP-5 Pump Room 5.58 Torpedo Defense System Equipment Room 23.23 Decoy RS Lkrs 11.15



Table 3.2-11

2000-Tonne SLC, Required Deck Area

Category Deck Area, m2 Task-Related Communications/Detect/Evaluation 255.95 Weapons 120.82 Aviation 157.99 Subtotal 534.76Personnel-Related 110 Accommodations @ 10.34m²/Accom 1137.83Ship Control Bridge 47.40 Ships Office 11.15 Subtotal 58.55Propulsion ECR 41.82 GT Intake & Exhausts 41.82 Diesel Intake & Exhausts 23.23 Stack 34.94 Subtotal 141.82Auxiliary Machinery HVAC, 5.5% of Gross Area 155.30 Mooring Aft P/S 27.88 Anchor/Mooring Fwd 18.59 Forward Auxiliary Machinery Space 36.25 SSDG Room Main Deck (Stbd) 38.38 Subtotal 276.39Maintenance 2 D.C. Lockers 14.87 Electronics/Electrical Shop 13.94 Mechanical Shop 27.88 Subtotal 56.69Stores 4.5% of Total Area 128.25Tankage Based on General Arrangements 33.46Passageways 12.5% of Total Area, Less Stack/Intakes 348.51Margin

5% of Useable Area, Less Hangar, Uptakes/Intakes, Aux. Mchry. Rooms, HVAC & Access 106.88

Total Required Area 2822.86 Note: This does not include the machinery box, deep tanks, or the Steering Gear Room.



3.2.6 Comparison of Offshore Patrol Vessels and Small Littoral Combatants The overall characteristics of the four OPC and SLC point designs are provided in Table 3.2-12. The data in this table summarizes many of the differences between OPCs and SLCs.

Table 3.2-12

Comparison of OPV and SLC Characteristics

600-Tonne 2000-Tonne Item OPV SLC OPV SLC

Length Between Perpendiculars, m 60.96 60.96 76.48 93.88 Beam at Design Waterline, m 7.79 8.71 13.81 13.23 Draft at Design Waterline, m 3.13 3.08 4.51 3.78 Average Hull Depth, m 5.56 6.37 10.88 9.07 Light Ship Displacement, Tonnes 547 590 1,859 1,964 Full-Load Displacement, Tonnes 682 763 2,321 2,465 Arrangeable Deck Area 665 742 2,261 2,827 Range, N.Mi/Speed 3,000/16 2,400/15 7,000/12 4,500/16 Speed, Knots 20.9 35.5 20.15 31.7 Sustainability, Days 7 7 30 20 Installed Propulsion Power, kW 5,222 21,880 8,952 35,570 Total Ships Service Electrical Cruising Load, kW

280 517 1,008 1,737

Number of Accommodations 30 48 88 110 Habitability, m2/Accom 10.31 7.04 11.17 10.08

The SLCs are much faster; hence, the ratio of installed power per tonne of full-load displacement is much higher, as follows:

600-tonne 2000-tonne Item OPV SLC OPV SLC Propulsion Power, kW/Full-Load Tonne 7.66 28.68 3.86 14.43

SLCs mount a significant payload of sensors and weapons, whereas OPVs do not. Therefore, the ratio of arrangeable area per light ship tonne is somewhat greater, as follows

600-tonne 2000-tonne Item OPV SLC OPV SLC Deck Area/Light Ship Tonne 1.216 1.258 1.216 1.439

The ship service electrical power cruising load per light ship tonne for SLCs is greater, as follows:

600-tonne 2000-tonne Item OPV SLC OPV SLC kW/ Tonne 0.512 0.877 0.542 0.884

Larger crews are required for SLCs, as follows:

600-tonne 2000-tonne Item OPV SLC OPV SLC Accom/Light Ship Tonne 0.055 0.081 0.047 0.056



Because SLCs must support larger crews that comprise naval vice professional mariners personnel, their habitability tends to be more austere, i.e. lower allocations of habitability-related deck area per accommodation.

600-tonne 2000-tonne Item OPV SLC OPV SLC Personnel-Related Area/Accom (sq.m/Accom) 10.31 7.04 11.11 10.34

Figures 3.2-5 and 3.2-6 provide comparisons of arrangeable deck area and light ship weight, respectively. As shown in Figure 3.2-5, SLCs have relatively more area allocated to mission-related spaces and less to auxiliary functions than do OPVs. Total personnel area allocations are about equal because the larger crews of the SLCs are offset by their lower habitability standards. As shown in Figure 3.2-6, SLCs have relatively less weight allocated to structure, auxiliary systems and outfitting than OPVs, and more weight allocated to propulsion, ship service electrical system, sensors and weapons. This reflects the use of lighter weight naval vice commercial structural design criteria, the proportionately increased propulsive power and ship service electrical loads, and the requirement for sensors and weapons. The higher speed, 2000-tonne SLC has a much lower displacement-to-length (Displ./(0.1L)³) ratio than the slower OPV, 2.979 vs 5.188, due to the impact of hull fineness on wave making (residual) resistance. Because of the desire to minimize displacement, both of the OPV designs generated herein employed aluminum vice steel superstructures. The length of the 600-tonne OPV was driven by the desire to provide a helicopter landing deck, whereas many small OPVs do not have helicopter landing decks. The range of the 2000-tonne SLC was also increased relative to the SAAR-V in order to provide greater operational time at full power. Each of these decisions has, to some limited extent, tended to mask some of the expected design differences. Generally, SLCs are expected to have somewhat less range and endurance than OPVs, and even relatively lighter structural weight fractions than shown in Figure 3.2-6.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

OPV SLC OPV SLC

600 Tonne 2000 Tonne

Margin

Access

Stowage

Maint

Aux

Propulsion

Admin

Crew

Mission

Figure 3.2-5. Comparison of Arrangeable Deck Area



0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Weapons

Outfitting

Auxiliaries

Electronics

Electrical

Propulsion

Structures

OPV 600 Tonne SLC OPV 2000 Tonne SLC

Figure 3.2-6. Comparison of Light Ship Displacement

3.3 Acquisition Costs In order to quantify the cost differences between OPVs and SLCs, the acquisition cost of the four notional point designs was estimated. In order to identify the cost impact of each variable considered by the sensitivity studies the acquisition cost of each of these was also developed. The labor rates and shipbuilding practices of NATO countries vary considerably. Several independent acquisition cost analyses were conducted. Both the Netherlands and the U.S. Coast Guard developed detailed acquisition cost estimates for each of the four notional point designs. The Netherlands cost estimate was based on manhour per ton and material cost per ton factors for each of the seven NATO Ship Work Breakdown Structure (SWBS) light ship weight groups. The U.S. Coast Guard cost estimate was based on 25 weight categories, each of the seven SWBS group being broken down into several subcategories. For example, SWBS Group 100, structure, was subdivided by the U.S. Coast Guard as follows:

− Steel Hull Structure, − Aluminum Hull Structure, − Steel Superstructure, − Aluminum Superstructure, − Foundations, and − Closures, Masts, Castings & Forgings

The U.S. Coast Guard cost estimate also incorporated separate budgetary costs for the engines, reduction gears, shafting and propulsors, propulsion control system, and ships service diesel generator sets. For C4ISR electronics and weapons the Netherlands and the U.S. Coast Guard both used a mutually agreed upon system-by-system payload cost budget. The comparative Netherlands and U.S. Coast Guard shipyard recurring costs per ton for SWBS Groups 100 to 700 and 900 are provided in Table 3.3-1. This table uses the Netherlands cost per tonne of Group 100 for the 2000 SLC as the baseline, with an assigned value of 100. The data shown in Table 3.3-1 is assessed to be reasonably consistent, with the following exceptions:

• 600 Tonne SLC



o Netherlands shipyard costs for structure auxiliary systems and outfitting are about 30% higher

• 2000 Tonne OPV o Netherlands shipyard costs for propulsion about 30% lower and installation of C4ISR about

60% higher • 600 Tonne OPV

o Netherlands shipyard costs for electrical, electronics, and auxiliary systems about 54% higher

Table 3.3-1 Netherlands and U.S. Coast Guard Cost Estimating Factors

2000 SLC 600 SLC 2000 OPV 600 OPV

SWBS NL USCG NL USCG NL USCG NL USCG 100, Structure 1.00 1.00 1.347 1.02 0.54 0.54 0.66 0.59 200, Propulsion 4.88 4.60 6.67 6.30 2.69 3.88 4.51 4.51 300, Electrical 5.64 5.97 7.29 4.45 3.53 3.12 4.49 2.69 400, Electronics 2.34 2.75 4.29 3.94 5.77 3.55 6.56 4.47 500, Auxiliaries 4.32 4.33 5.48 4.12 3.06 2.94 4.87 3.23 600, Outfitting 5.00 5.48 5.89 4.50 3.35 4.34 4.17 4.37 700, Armament 0.90 1.30 1.09 1.15 4.52 1.02 3.37 1.14 900,Shipyard Administration

0.34 0.53 0.51 0.53 0.14 0.53 0.21 0.53

The overall correlation of U.S. Coast Guard and Netherlands shipyard production costs (SWBS Group 100-700 inc.) is assessed to be good, as follows:

Shipyard Production Cost Ship Netherlands U.S. Coast Guard 600 SLC 1.0 1.153 2000 SLC 1.0 1.024 600 OPV 1.0 1.093 2000 OPV 1.0 0.826 Overall Correlation 1.0 1.0394

Netherlands shipyard administrative costs (SWBS Group 900) for OPVs were about half those estimated by the U.S. Coast Guard. This is judged to reflect the influence of lower cost commercial practices as U.S. shipyards primarily produce naval or Coast Guard ships both of which are similarly procured. Similarly, the Netherlands has also estimated lower design costs for OPVs. The report will subsequently use the U.S. Coast Guard cost-estimating factor to identify the relative impacts of the sensitivity studies. It is estimated that similar impacts would have been obtained had any other set of costing factors been used. Figure 3.3-1 provides the relative lead ship costs of the four notional point designs. The acquisition cost of SLCs is much higher than OPVs of comparable size. This primarily reflects the higher cost of the payload, propulsion and engineering. Figure 3.3-2 provides the distribution of lead ship costs. As shown in this Figure for SLC payload (C4ISR electronics and weapons) represents a much larger proportion of total cost. For the OPVs auxiliary systems and outfitting represent a larger proportion of lead ship cost. Engineering, SWBS Group 800, represents a large proportion of lead ship costs, particularly for the smaller ships.



0

1

2

3

4

5

Normalize Cost

PAYLOAD

ADMINISTRATION

ENGINEERING

ARMAMENT (W/O PAYLOAD)

OUTFITTING

AUXILIARIES

ELECTRONICS (W/O PAYLOAD)

ELECTRICAL

PROPULSION

STRUCTURE

600 OPV 600 SLC 2000 OPV 2000 SLC

Figure 3.3-1 Relative Lead Ship Costs

0%

10%20%

30%

40%

50%

60%70%

80%

90%

100%

OP

V

SLC

OP

V

SLC

600 TONNE 2000 TONNE

PE

RC

EN

T O

F T

OT

AL

CO

ST

PAYLOAD

SHIPYARD ADMINISTRATION

ENGINEERING

WEAPONS INSTALLATION

OUTFITTING

AUXILIARY SYSTEMS

C4ISR INSTALLATION, I.C. &DEGAUSSINGELECTRICAL

PROPULSION

STRUCTURES

Figure 3.3-2 OPV vs. SLC Distribution of Lead Ship Costs



As shown in Figure 3.3-3 the platform cost per light ship tonne of SLCs is much higher than that of OPVs. This reflects the need for relatively higher propulsive power and electrical generating capacity, lower signatures, and higher quality, more survivable systems.

0

1

2

3

4

5

6

OPV SLC OPV SLC

600 TONNE 2000 TONNE

No

rmal

ized

P

latf

orm

Co

st/L

igh

t S

hip

T

on

ne

SWBS GROUPS 1-7 INCL. W/O WEAPONS & SENSORS

Figure 3.3-3 OPV vs. SLC, Platform Cost/Light Ship Tonne Figure 3.3-4 shows that the comparative total cost per ton of SLCs is much higher than the of OPVs because of the proportionately much higher payload cost of C4ISR electronics and weapons, and the somewhat higher cost per tonne of the platform. This analysis has shown that for both OPVs and SLCs as displacement increases the cost per tonne decreases.

-

1

2

3

4

5

6

7

O P V S L C O P V S L C

6 0 0 T O N N E 2 0 0 0 T O N N E

Nor

mal

ized

To

tal C

ost

/Lig

ht S

hip

P A Y L O A D

P L A T F O R M

Figure 3.3-4 OPVs vs. SLC, Total Cost per Tonne



3.4 Sensitivity Studies 3.4.1 Introduction To support the aims of this Working Paper, the following sensitivity studies were conducted. These were based on the four point designs, as follows:

• 600-Tonne OPV - Increased range - Increased speed

• 2000-Tonne OPV

- Improved ability to operate in mined waters - Increased range - Increased speed

• 600-Tonne SLC - Using an aluminum vice steel hull - Reduced or enhanced habitability standards - Deleting aviation capability

• 2000-Tonne SLC - Adding ballistic protection - Changing from an aluminum to a steel superstructure - Increased range - Increased speed - Additional hull and superstructure volume at varying densities

The approach taken for the sensitivity studies was to, again, employ a ship design synthesis computer program. For each sensitivity study, the appropriate OPV or SLC point design was used as the parent design and reference point. Aside from the speed and range studies, each new design has the same:

• range, • speed, • stability, in terms of GMv/BDWL ratio, and • arrangeable deck area

as the baseline. Therefore, each new point design would be suitable for direct comparison with the parent/baseline. In order to balance speed, the power of the main propulsion diesel engines was adjusted accordingly. In so far as possible, each parametric equation and all design criteria or practices were adjusted as appropriate to precisely reflect the impact of the variable being studied. Tables 3.4-1, 3.4-2, 3.4-3 and 3.4-4 provide the summary of ship characteristics for all sensitivity design studies conducted for the 600-tonne OPV, 2000-tonne OPV, 600-tonne SLC, and 2000-tonne SLC, respectively. These tables provide the hull dimensions, speed, range, light ship and load weights, required deck area, propulsive power and ship service electrical cruising load for each sensitivity study design. This data can be compared to that of the baseline point design, which is also provided in each table.



Table 3.4-1

600-Tonne OPV, Studies

Trade-Off Studies Item

Baseline 600-Tonne

OPV 10% Increased

Range Plus One Knot

Sustained Speed Length Between Perpendiculars, m 60.96 60.96 60.96 Beam at Design Waterline, m 7.79 7.78 7.74 Draft at Design Waterline, m 3.13 3.20 3.22 Average Hull Depth, m 5.56 5.56 5.56 Trial Speed, Knots 20.85 20.85 21.85 Range, N.Mi/Knots 2,999/16 3,299/16 2,999/16 Accommodations 30 30 30 Habitability, m²/Accom 9.67 9.81 9.48 Light Ship Wt., tonnes: Structures 263.4 264.1 263.3 Propulsion 67.4 70.9 81.0 Electrical 29.0 29.0 29.0 Electronics 11.8 11.8 11.8 Auxiliary 79.1 79.5 79.3 Outfitting 50.8 50.7 50.5 Weapons 4.7 4.7 4.7 Total, incl. D&C Margin 546.7 551.6 561.3 F.O. Load 91.9 102.00 9.0 Other Loads 43.7 43.7 43.7 Full-Load Displacement, tonne 682.3 697.3 698.0 Required Deck Area, m2: Payload 134.8 134.8 134.80 Personnel 290.1 294.2 284.30 Platform 240.0 240.0 240.00 Total Required Deck Area 664.9 669.0 659.1 Propulsive Power, kW 5,222 5,373 6,624 Cruising Ship Service Electrical Load, kW 280 280 279



Table 3.4-2

2000-Tonne OPV, Studies


Baseline 600-Tonne OPV

Operations in Mined Waters 10% Increased

Range Plus One Knot

Sustained Speed Length Between Perpendiculars, m 76.48 76.48 76.48 76.48 Beam at Design Waterline, m 13.81 13.89 13.81 13.79 Draft at Design Waterline, m 4.51 4.77 4.58 4.60 Average Hull Depth, m 10.88 10.88 10.88 10.88 Trial Speed, Knots 20.15 20.15 20.15 21.15 Range, N.Mi/Knots 7,000/12 7,003/12 7,701/12 7,002/12 Accommodations 88 88 88 88 Habitability, m²/Accom 11.20 11.17 11.16 11.12 Light Ship Weight, Tonnes: Structures 865.9 938.9 865.9 868.1 Propulsion 188.2 223.1 190.6 224.3 Electrical 92.2 92.4 92.2 92.2 Electronics 33.1 44.0 33.1 33.1 Auxiliary 284.8 289.3 285.6 285.7 Outfitting 249.9 250.9 249.9 249.6 Weapons 7.0 7.0 7.0 7.0 Total, incl. D&C Margin 1,858.6 1,993.2 1,862.1 1,900.7 F.O. Load, Tonnes: 275.1 284.2 303.2 276.3 Other Loads, Tonnes: 187.3 187.9 187.5 187.5 Full-Load Displacement, Tonnes: 2,321.00 2,465.3 2,352.8 2,364.5 Required Deck Area, m²: Payload 336.1 336.1 336.1 336.1 Personnel 986.0 982.8 982.0 978.3 Platform 939.0 939.0 939.0 939.0 Total Required Deck Area 2,261.1 2,257.9 2,257.1 2,253.4 Propulsive Power, kW 8,952 9,549 9,083 11,288 Cruising Ship Service Electrical Load, kW 1,008 1,047 1,008 1,009



Table 3.4-3

600-Tonne SLC, Studies


Baseline 600-Tonne SLC Aluminum Hull Reduced

Habitability Enhanced

Habitability 10% Increased

Range Plus One Knot

Sustained Speed Length Between Perpendiculars, m 60.96 60.96 60.96 63.09 60.96 60.96 Beam at Design Waterline, m 8.71 8.59 8.65 8.73 8.71 8.70 Draft at Design Waterline, m 3.08 2.77 3.06 3.05 3.14 3.11 Average Hull Depth, m 6.10 6.10 6.10 6.10 6.10 6.10 Trial Speed, Knots 35.50 35.50 35.50 35.50 35.50 36.50 Range, N.Mi/Knots 2,398/15 2,376/15 2,397/15 2,397/15 2,638/15 2,398/15 Accommodations 48 48 48 48 48 48 Habitability, m²/Accom 6.81 6.62 5.54 9.01 6.75 6.77 Light Ship Weight, tonnes: Structures 189.7 127.1 185.8 198.6 190.0 190.2 Propulsion 125.5 114.3 125.3 128.2 129.0 132.1 Electrical 29.2 29.1 28.8 29.9 29.2 29.2 Electronics 42.5 42.4 42.4 42.8 42.5 42.5 Auxiliary 78.1 85.1 76.6 81.7 78.5 78.3 Outfitting 52.6 49.7 51.0 56.2 52.6 52.6 Weapons 28.9 28.9 28.9 28.9 28.9 28.9 Total, incl. D&C Margin, Tonnes 590.1 514.7 582.0 611.6 594.7 598.0 F.O. Load, Tonnes 102.0 92.4 401.0 101.4 113.0 102.8 Other Loads, Tonnes 71.0 70.7 71.0 71.1 71.1 71.0 Full-Load Displacement, Tonnes 763.1 677.9 754.0 784.1 778.8 771.8 Required Deck Area, m²: Payload 179.7 179.7 179.70 179.70 179.7 179.7 Personnel 326.7 317.6 266.10 432.50 323.9 324.9 Platform 236.0 236.0 229.00 231.6 236.0 236.0 Total Required Deck Area 742.4 733.3 674.8 843.8 739.6 740.6 Propulsive Power, kW 21,872 19,223 21,804 22,529 22,464 23,126 Cruising Ship Service Electrical Load, kW

517 513 506 534 518 517



Table 3.4-4

Summary of Ship Characteristics, 2000-Tonne SLC, Studies

Trade-Off Studies

Item Baseline

2000-Tonne SLC

Comprehensive Ballistic

Protection

Limited Ballistic

Protection

Steel vs Aluminum

Superstructure

10% Increased Range

Plus One Knot Sustained Speed

Length Between Perpendiculars, m 93.88 93.88 93.88 93.88 93.88 93.88 Beam at Design Waterline, m 13.23 13.69 13.56 13.59 13.27 13.23 Draft at Design Waterline, m 3.78 3.91 3.82 3.83 3.83 3.86 Average Hull Depth, m 9.07 9.07 9.07 9.07 9.07 9.07 Trial Speed, Knots 31.94 31.91 31.91 31.91 32.00 33.26 Range, N.Mi/Knots 4,499/16 4,508/16 4,502/16 4,507/16 4,950/16 4,501/16 Accommodations 110 110 110 110 110 110 Habitability, m²/Accom 10.38 10.40 10.38 10.29 10.39 10.30 Light Ship Weight, tonnes: Structures 765.4 890.1 832.5 845.2 767.8 768.8 Propulsion 314.2 325.9 320.4 322.1 322.6 350.0 Electrical 77.4 80.3 77.4 77.4 77.5 77.5 Electronics 160.4 161.3 161.0 161.1 160.5 160.4 Auxiliary 228.5 232.5 231.0 230.3 230.2 230.1 Outfitting 196.9 197.0 196.6 196.5 197.2 196.9 Weapons 76.0 76.0 76.0 76.0 76.0 76.0 Total, incl. D&C Margin, Tonnes 1,964.4 2,120.1 2,046.6 2,061.3 1,978.4 2,008.5 F.O. Load, Tonnes 283.3 296.1 286.6 287.6 313.0 286.0 Other Loads, Tonnes 218.1 219.1 218.6 218.7 218.4 223.5 Full-Load Displacement, Tonnes 2,465.8 2,635.3 2,551.9 2,567.6 2,509.7 2,518.0 Required Deck Area, m²: Payload 534.8 534.8 534.8 534.8 534.8 534.8 Personnel 1,142.3 1,143.9 1,141.3 1,131.6 1,142.5 1,133.5 Platform 1,150.3 1,159.2 1,157.8 1,153.2 1,150.3 1,150.3 Total Required Deck Area 2,827.4 2,837.9 2,833.9 2,819.6 2,827.6 2,818.6 Propulsive Power, kW 35,547 38,426 37,084 37,348 36,318 40,603 Cruising Ship Service Electrical Load, kW

1,737 1,766 1,757 1,760 1,740 1,741

NATO PfP UNCLASSIFIED


3.4.2 600-Tonne OPV Studies 3.4.2.1 Increased Range The range of the 600-tonne OPV was increased by ten percent. Increasing range by ten percent had the following impact:

Item Baseline Range Plus Ten Percent

Percent Impact

Range, N.Mi/Knots 2,999/16 3,299/16 +10 Length Between Perpendiculars, m 60.96 60.96 None Beam at Design Waterline, m 7.79 7.78 -0.1 Draft at Design Waterline, m 3.13 3.20 +2.2 Light Ship Displacement, including D&C Margin, tonnes

546.7 551.6 +0.9

Fuel Oil Load, tonnes 91.9 102.0 +10.9 Full-Load Displacement, tonnes 682.3 697.3 +2.2 Total Installed Propulsion Power, kW 5,222 5,373 +2.9 Ship Service Cruising Electrical Load, kW 280 280 None Normalized Acquisition Cost 100.0 100.7 +0.7

The cost impact associated with increasing range is primarily due to the increase in propulsion power required to maintain speed. 3.4.2.2 Increased Speed The baseline trial speed was increased one knot by employing more powerful diesel engines. It was assumed that these more powerful engines could be installed within the baseline machinery box. For the purposes of this trade-off study, hull length was not increased to reduce resistance. Increasing speed by one knot had the following impact:

Item Baseline Plus One Knot Speed

Percent Impact

Trial Speed, Knots 20.85 21.85 +4.8 Length Between Perpendiculars, m 60.96 60.96 None Beam at Design Waterline, m 7.79 7.74 -0.6 Draft at Design Waterline, m 3.13 3.22 +2.9 Light Ship Displacement, Including D&C Margin, tonnes

546.7 561.3 +2.7

Fuel Oil Load, tonnes 91.9 93.0 +1.2 Full-Load Displacement, tonnes 682.3 698.0 +2.3 Total Installed Propulsion Power, kW 5,222 6,624 +26.8 Ship Service Cruising Electrical Load, kW 280 279 -0.4 Normalized Acquisition Cost 100.0 103.5 +3.5

At slow speeds, resistance is generally a function of speed cubed. However, at moderate speeds, the hull’s residual resistance coefficient increases very rapidly. Therefore, resistance at moderate speeds (Froude Numbers between .025 and .050) can vary by the speed raised to the fourth power. Consequently, for a moderate speed OPV, a one-knot increase in calm water speed results in a 26.8% increase in required propulsive power and, hence, a 3.5% increase in shipyard construction cost.



3.4.3 2000-Tonne OPV Studies 3.4.3.1 Operation in Mined Waters Some OPVs have to operate within mined waters. To provide increased survivability when operating under these conditions, the baseline 2000-tonne OPV was modified as follows:

• The ship was designed to meet NATO standard shock toughness criteria. This increases the weight of foundations and the acquisition cost of impacted equipment and systems.

• In so far as feasible, the ship’s underwater signatures were reduced. Degaussing was added to neutralize the magnetic signature. In order to reduce the ship’s acoustic signatures:

- Larger diameter, lower RPM propellers were used to delay the onset of cavitation. - In order to reduce the transmission of airborne noise, the engines were mounted within

acoustically shrouded enclosures. - The engines and reduction gears were mounted on a large, soft-mounted bedplate, thereby

reducing the transmission of structureborne noise. The results of the trade-off study were as follows:

Item Baseline Study Percent Impact Length, m 76.48 76.48 None Beam, m 13.81 13.89 +0.6 Draft, m 4.51 4.77 +5.8 Light Ship Displacement, tonnes 1,858.6 1,993.2 +7.2 Fuel Oil Load, tonnes 275.1 284.2 +3.3 Full-Load Displacement, tonnes 2,321.0 2,465.3 +6.2 Propulsion Power, kW 8,952 9,549 +6.7 Normalized Acquisition Cost 100.0 108.1 +8.1

The impact of shock toughness and underwater signature reduction has a limited impact on displacement and propulsion power. However, the provision of shock toughness considerably increases shipyard acquisition cost because of the quality required for vital equipment and systems. The lead ship cost also increases because of the impact of increased design engineering effort. It should be noted that this trade-off study continued to employ commercial structures, although naval structures are somewhat more resistant to underwater explosions. The cost impact would have grown even more significant had hull structures also been changed from commercial to naval design practice. 3.4.3.2 Increased Range The range of the 2000-tonne OPV was increased by ten percent. Increasing range by ten percent has the following impact:


Percent Impact

Range, N.Mi/Knots 7,700/12 7,700/12 +10 Length Between Perpendiculars, m 76.48 76.48 None Beam at Design Waterline, m 13.81 13.81 None Draft at Design Waterline, m 4.51 4.58 +1.6 Light Ship Displacement, Including D&C Margin, tonnes

1,858.6 1,862.1 +0.2

Fuel Oil Load, tonnes 275.1 303.2 +10.2 Full-Load Displacement, tonnes 2,321.0 2,352.8 +1.4 Total Installed Propulsion Power, kW 8,952 9,083 +1.5 Ship Service Cruising Electrical Load, kW 1,008 1,008 None Normalized Acquisition Cost 100.0 100.1 +0.1



The cost impact associated with increasing range is primarily due to the increase in propulsion power required to maintain speed. 3.4.3.3 Increased Speed The baseline trial speed of the 2000-tonne OPV was increased one knot by employing more powerful diesel engines. It was assumed that the more powerful engines could be installed within the baseline machinery box. For the purposes of this trade-off study, the hull length was not increased, nor was the baseline hull form adjusted to reduce resistance. Increasing speed by one knot by providing additional propulsive power has the following impact:


Percent Impact


1,858.6 1,900.7 +2.3

Fuel Oil Load, tonnes 275.1 276.3 +0.4 Full-Load Displacement, tonnes 2,231.0 2,364.5 +1.9 Total Installed Propulsion Power, kW 8,952 11,288 +26.1 Ships Service Cruising Electrical Load, kW 1,008 1,009 None Normalized Acquisition Cost 100.0 102.7 +2.7

3.4.4 600-Tonne Small Littoral Combatant Studies 3.4.4.1 Aluminum Hull The baseline hull is constructed of longitudinally framed steel with aluminum internal bulkheads and an aluminum platform deck. The bottom structure and deep tank boundaries that support the outer hull are all steel. The baseline superstructure is constructed of 5mm to 8mm aluminum plating, supported by continuously welded, relatively widely-spaced aluminum T-shaped longitudinal beams and web frames. The trade-off study employed a lightweight, longitudinally-framed, aluminum hull and a lightweight aluminum superstructure, constructed of 4mm to 6.5mm aluminum plating, supported by more closely-spaced, riveted, Z-shaped longitudinals and intermittently welded T-shaped web frames. Employing lightweight structures has the following impact:

Item Baseline Using

Lightweight Structures

Percent Impact

Length Between Perpendiculars, m 60.96 60.96 None Beam at Design Waterline, m 8.71 8.59 -1.4 Draft at Design Waterline, m 3.08 2.77 -10.1 Hull Structure Weight, t 128.29 87.25 -32.0 Superstructure Weight, t 21.30 16.38 -23.1 Light Ship Displacement, Including D&C Margin, tonnes

590.1 514.7 -12.8

Fuel Oil Load, tonnes 102.0 92.4 -9.4 Full-Load Displacement, tonnes 763.1 677.9 -11.2 Total Installed Propulsion Power, kW 21,872 19,223 -12.1 Ships Service Cruising Electrical Load, kW 517 513 -0.8 Normalized Acquisition Cost 100.0 95.3 -4.7



The cost per tonne of aluminum hull structure, including labor, materials and profit, is substantially higher than that of steel structures. Aluminum structures, however, are lighter in weight, and this has a significant design spiral impact on a relatively fast, high-powered ship like the baseline 600-tonne SLC. Consequently, this study indicates that using a lighter weight, more costly hull material results in an overall cost reduction in the recurring shipyard cost. This occurred because of the substantial reduction in ship size and, hence, the significant reduction in the cost of the propulsion system, which represents a substantial portion of the overall construction cost. 3.4.4.2 Reduced Habitability The baseline 600-tonne SLC has significantly better habitability than most existing fast attack craft. Therefore, the impact of reduced habitability standards conforming to past practices was studied. The use of reduced habitability standards has the following impact:

Item Baseline Reduced Habitability

Percent Impact

Deck Area/Accommodation, m² 6.81 5.54 -18.6 Length Between Perpendiculars, m 60.96 60.96 None Beam at Design Waterline, m 8.71 8.65 -0.7 Draft at Design Waterline, m 3.08 3.06 -0.6 Personnel-Related Deck Area, m² 326.7 266.10 -18.6 Total Required Deck Area, m² 742.4 674.8 -9.1 Light Ship Displacement, Including D&C Margin, tonnes

590.1 582.0 -1.4

Fuel Oil Load, tonnes 102.0 101.0 -1.0 Full-Load Displacement, tonnes 763.1 754.0 -1.2 Total Installed Propulsion Power, kW 21,872 21,804 -0.3 Ships Service Cruising Electrical Load, kW 517 506 -2.3 Normalized Acquisition Cost 100.0 97.7 -2.3

In the 600-tonne SLC, the reduction in required habitability-related deck area could be accomplished by reducing the size of the lightweight aluminum superstructure. Consequently, the design spiral impact of this reduction was relatively limited because it had a very limited impact on displacement. 3.4.4.3 Enhanced Habitability Although the baseline 600-tonne SLC has significantly better habitability than existing fast attack craft, the allocation of personnel-related deck area per accommodation is lower than that which would be provided on future, larger, international littoral combatants. Therefore, the impact of enhanced habitability standards was studied.



The use of enhanced habitability standards has the following impact:

Item Baseline Enhanced Habitability

Percent Impact

Deck Area/Accommodation, m² 6.81 9.04 +32.7 Length Between Perpendiculars, m 60.96 63.09 +3.5 Beam at Design Waterline, m 8.71 8.73 +0.2 Draft at Design Waterline, m 3.08 3.05 -1.0 Personnel-Related Deck Area, m² 326.7 432.5 +32.4 Total Required Deck Area, m² 742.4 843.8 +13.7 Light Ship Displacement, Including D&C Margin, tonnes

590.1 611.6 +3.6

Fuel Oil Load, tonnes 102.0 101.4 -0.6 Full-Load Displacement, tonnes 763.1 784.1 +2.8 Total Installed Propulsion Power, kW 21,872 22,529 +3.0 Ships Service Cruising Electrical Load, kW 517 534 +3.3 Normalized Acquisition Cost 100.0 103.4 +3.4

The baseline design had a relatively large superstructure with tiered command and control spaces and antennas forward, canister launched missiles located midships above the 01 Level, and a hangar located aft. The superstructure could not be increased in length because of the forward gun location and the required length of the helicopter landing deck aft. Consequently, providing additional habitability deck area required lengthening of both the hull and superstructure, whereas it is generally feasible to enlarge the superstructure without lengthening the hull. Stretching the hull has increased the impact of providing enhanced habitability because in this case it results in a relatively limited increase in required propulsive power, which is relatively expensive. 3.4.4.4 Increased Range The range of the 600-tonne SLC was increased by ten percent. Increasing the range by ten percent has the following impact:

Item Baseline Plus Ten Percent Range

Percent Impact

Range, N.Mi/Knots 2,398/15 2,638/15 +10.0 Length Between Perpendiculars, m 60.96 60.96 None Beam at Design Waterline, m 8.71 8.71 None Draft at Design Waterline, m 3.08 3.14 +1.9 Light Ship Displacement, Including D&C Margin, tonnes

590.1 594.7 +0.8

Fuel Oil Load, tonnes 102.0 113.0 +10.8 Full-Load Displacement, tonnes 763.1 778.8 +2.1 Total Installed Propulsion Power, kW 21,872 22,464 +2.7 Ships Service Cruising Electrical Load, kW 517 518 +0.2 Normalized Acquisition Cost 100.0 101.0 +1.0

The limited cost impact associated with increasing range primarily reflects the increase in propulsion power which is required to maintain speed.



3.4.4.5 Increased Speed The baseline speed was increased one knot by employing more powerful diesel engines. It was assumed that the more powerful engines could be installed within the baseline machinery box. For the purposes of this trade-off study, the hull length was not increased, nor was the baseline hull form adjusted to reduce high-speed resistance. Increasing speed by one knot has the following impact:


Percent Impact


590.1 598.0 +1.3

Fuel Oil Load, tonnes 102.0 102.8 +0.8 Full-Load Displacement, tonnes 742.4 771.8 +4.0 Total Installed Propulsion Power, kW 21,872 23,126 +5.7 Ships Service Cruising Electrical Load, kW 517 517 None Normalized Acquisition Cost 100.0 102.1 +2.1

3.4.5 2000-Tonne Small Littoral Combatant Studies 3.4.5.1 Comprehensive Ballistic Protection The baseline design did not have ballistic protection. Its relatively light superstructure and hull scantlings offer minimal protection against various threat weapons. While it is inherently obvious that it is impossible to protect a small littoral combatant against large caliber weapons, this study addresses:

• 23mm armor piercing rounds fired at a stand-off range of 500m and impacting at an obliquity angle of 90 degrees.

• Reinforcing transverse W.T. bulkheads to withstand a 250kg high-explosive warhead at a stand-off range of 5 meters.

• Protection of topside magazines against penetration by RPG-7-type shaped charge warheads.

• Provision of port and starboard longitudinal protective trunks for vital fore-and-aft distributed systems.

State-of-the-art supplementary ballistic protection was employed to defeat 23mm AP projectiles and 250kg warhead fragments. A mass equivalence ratio of 2.25 (i.e. 1kg/sq.m of special material = 2.25kg/sq.m of mild steel) was assumed for this supplementary protection. This can be provided by encapsulated layers of small ceramic spheres located with a low density matrix or other advanced materials. In order to defeat 23mm AP rounds at a 500m stand-off range, it was assumed that 97.63kg/sq.m of surface area of special material would be required. In order to reduce the number of penetrating fragments generated by a 250kg high explosive warhead at a 5m stand-off range to less than two per square meter of bulkhead surface area, it was assumed that 76.68kg/sq.m of special material would be required. It was assumed that the baseline hull would generate at least 20 calibers of stand-off distance between the forward gun magazine boundaries and an instantly-fused shaped charge warhead. At this stand-off distance, the current state-of-the-art RPG-7 threat can penetrate about 300mm of mild steel. The use of encapsulated reactive armor, with an overall system mass equivalence ratio of 7.5, was assumed for magazine protection at a weight of 434.4kg per square meter of magazine boundary surface area.



Two longitudinal protective trunks were assumed to be relatively heavy structural tubes, each weighing 0.37T/meter. The comprehensive ballistic protection trade-off study had the following impact:

Item Baseline Comprehensive Ballistic Protection

Percent Change

Length Between Perpendiculars, m 93.88 93.88 None Beam at Design Waterline, m 13.23 13.69 +3.5 Draft at Design Waterline, m 3.78 3.91 +3.4 Light Ship Displacement, Including D&C Margin, tonnes

1,964.4 2,120.1 +7.9

Fuel Oil Load, tonnes 283.3 296.1 +4.5 Full-Load Displacement, tonnes 2,465.8 2,635.3 +6.9 Total Installed Propulsion Power, kW 35,547 38,426 +8.1 Ships Service Cruising Electrical Load, kW 1,737 1,766 +1.7 Normalized Acquisition Cost 100.0 107.8 +7.8

It is assessed that the increased acquisition cost associated with the provision of ballistic protection primarily reflects both the cost of the advanced materials used and the increase in total installed propulsion power required to offset the impact on resistance of the growth in displacement. In this case, provision of ballistic protection equivalent to 6.9 percent (including the associated D&C margin) of the baseline full-load displacement results in an 8.1 percent increase in propulsive power and a 7.8 percent increase in recurring shipyard cost. 3.4.5.2 Limited Ballistic Protection In this trade-off study, only the 23mm AP threat was addressed. This reduced the total amount of ballistic protection required, as follows:

Category Wt., t KG, m Comprehensive 106.2 10.45 Limited 55.6 13.28

The limited ballistic protection trade-off study had the following impact:

Item Baseline Limited Ballistic

Protection

Percent Impact


1,964.4 2,046.6 +4.2




3.4.5.3 Steel Superstructure The baseline 2000-tonne SLC had an aluminum superstructure. This trade-off study addresses the impact of employing steel versus aluminum for the superstructure. The steel superstructure trade-off study had the following impact:

Item Baseline Steel Superstructure

Percent Change

Weight of Superstructure w/o D&C Margin, tonnes

84.3 148.4 +76.0


1,964.4 2,061.3 +4.9


3.4.5.4 Increased Range The range of the 2000-tonne SLC was increased by ten percent. Increasing range had the following impact:


Percent Change

Range, N.Mi/Knots 4,499/16 4,950/16 +10.0 Length Between Perpendiculars, m 93.88 93.88 None Beam at Design Waterline, m 13.23 13.27 +0.3 Draft at Design Waterline, m 3.78 3.83 +1.3 Light Ship Displacement, Including D&C Margin, tonnes

1,964.4 1,978.4 +0.7


The limited cost impact associated with increasing range is primarily due to the increase in propulsion power required to maintain speed. 3.4.5.5 Increased Speed The baseline sustained speed at the full-load displacement was increased by one knot by employing more powerful diesel engines for the outboard shafts. It was assumed that these more powerful engines could be installed within the baseline machinery box. For the purpose of this trade-off study, hull length was not increased to reduce resistance and no change was made to the hull form.



Increasing speed by one knot had the following impact:


Percent Change

Sustained Speed, Knots 29.16 30.16 +3.4 Length Between Perpendiculars, m 93.88 93.88 None Beam at Design Waterline, m 13.23 13.23 None Draft at Design Waterline, m 3.78 3.86 +2.1 Light Ship Displacement, Including D&C Margin, tonnes

1,964.4 2,008.5 +2.2


The shipyard platform acquisition cost impact of modified speed and/or range is primarily a factor of the Froude Number of the ship being studied. The faster the hull, the greater the cost impact of increased range. At relatively slow speed (Fn = 0.385), the cost impact is only 0.01 percent of platform cost per percent of increased range. At relatively high speed (Fn = 0.757), the platform cost impact increases to 0.10 percent of cost per percent of increased range. Consequently, for all ships, limited changes in range will generally result in relatively small changes in platform acquisition cost. Moreover, this impact is almost entirely due to the change in propulsive power required to maintain speed as range is changed. Had speed been allowed to change, the impact of range on platform acquisition cost would have been significantly reduced. Up to a “hump” Froude Number of about 0.50, the percent of impact of increased speed on acquisition cost continuously increases from about 0.5 to 1.0 times the percent increase in speed. Beyond the “hump”, Froude Number hull resistance begins to be progressively reduced relative to speed raised to the third power. Thus, as the Froude Number increases from 0.50 to about 0.75, the percent impact of increased speed on acquisition cost declines from about 1.0 to 0.75 times the percent change in speed. This means that a 10 percent increase in speed would increase the shipyard recurring cost by 5 percent to 10 percent, depending on hull speed, whereas a 10 percent increase in range would increase cost by only 0.1 percent to 1.0 percent. Speed, therefore, has a significantly greater impact on acquisition cost than range. The impact on shipyard recurring platform acquisition cost varied from –4.7 percent to +8.1 percent for all the factors studied herein, as follows: Platform Feature Cost Impact, percent

2000 OPV Shock Toughness & Low Magnetic and +8.1 Acoustic Signatures 2000 SLC Significant Ballistic Protection +7.8 2000 SLC Moderate Ballistic Protection +4.0 600 SLC Improved Habitability +3.4 2000 SLC Steel vs. Aluminum Superstructure +1.0 600 SLC Reduced Habitability -2.3 600 SLC Aluminum vs. Steel Hull -4.7



3.4.5.6 Impact of Volume and Weight The 2000-tonne SLC was also used as the baseline to conduct a series of sensitivity studies identifying the impact of volume and weight on ship size and cost. The following studies were conducted:

• Light ship weight was added to the topsides, external to the hull, within the superstructure above the Main Deck, or within the hull.

• Volume was added to the superstructure or the hull at varying densities based on the additional dedicated weight enclosed within each cubic meter of volume.

The volume and weight studies were conducted using a ship design synthesis program. The sustained speed of each trade-off study was identical to that of the baseline. This was accomplished by adjusting the power levels of the main propulsion diesel engines to offset any resulting increase or decrease in hull resistance. In so far as reasonable, arrangeable deck area was also held constant, except as adjusted to reflect the impact of increased hull or superstructure volume. This was accomplished by adjusting hull length and/or superstructure dimensions, as appropriate. In most cases, the variation between available and required deck area was within 0.3 percent. The results of the trade-off studies are summarized in Table 3.4-5. These point design studies are suitable for direct comparison.



Table 3.4-5

Summary of Results, Volume and Weight Studies

Item Added Hull Volume Added Superstructure Volume

2000-tonne SLC

Baseline

Added Hull

Weight 0.0 t/m³ 0.1339 t/m³

0.2030 t/m³

Added Topside Weight 0.0 t/m³ 0.164 t/m³ 0.268 t/m³

Hull Volume, m³ 8,079.09 8,081.62 8,159.00 8,169.21 8,108.81 8,107.84 8,082.70 8,084.11 8,087.88 Superstructure Volume, m³ 3,503.41 3,505.09 3,495.30 3,499.21 3,502.32 3,510.46 3,531.20 3,540.24 3,548.37 Added Wt/KG, t/m None 15.24/5.75 0.0/0.0 12.06/5.75 6.04/5.75 12.16/10.21 0.0/0.0 6.04/12.88 12.06/12.88 Length Between Perpendiculars, m

93.88 93.88 95.01 95.06 94.24 93.88 93.88 93.63 93.42

Beam at Design Waterline, m 13.23 13.26 13.20 13.22 13.23 13.29 13.24 13.28 13.33 Draft at Design Waterline, m 3.78 3.80 3.76 3.78 3.78 3.79 3.78 3.79 3.80 Light Ship Displacement, incl. D&C Margin, t

1,964.44 1,985.94 1,975.96 1,992.13 1,975.87 1,984.45 1,966.70 1,975.13 1,985.14

Fuel Oil Load, t 283.26 284.30 282.96 284.04 283.86 284.14 283.36 283.67 284.07 Full-Load Displacement, t 2,465.82 2,488.49 2,477.10 2,494.47 2,477.93 2,486.83 2,468.20 2,476.98 2,487.45 Total Propulsive Power, kW 35,547 35,936 34,995 35,211 35,519 35,913 35,620 35,906 36,269 Available Deck Area, m² 2,826.94 2,829.06 2,856.27 2,853.70 2,834. 66 2,836.15 2,839.06 2,840.43 2,842.70



Results Addition of Weight Above the Main Deck The impacts per tonne of additional weight located 1.22m above the Main Deck of the 2000-tonne SLC are as follows:

Item Per Tonne of Added Weight

Light Ship, including D&C Margin, tonnes 1.6577 Fuel Oil Load, tonnes 0.0724 Full-Load Displacement, tonnes 1.7403 Propulsion Power, kW 30.9957

The per-added-tonne impacts noted above will vary somewhat for weight added topsides to OPVs or other SLCs, primarily depending on:

• Hull Density, with the study based on a baseline density of 0.243t/m³ of hull volume.

• Range, with the baseline fuel load/full-load ratio equal to 0.115.

• Speed, with the maximum baseline Froude Number equal to 0.54 at the trial speed at the mean trial loading condition.

A hull density that is higher than the baseline value will increase the impact of added external weight on light ship. Increasing the fuel oil weight fraction beyond the baseline value will result in an increased impact on fuel oil load. Increasing both the hull density and the fuel weight fraction will tend to further increase the impact on the fuel oil load. The maximum baseline Froude Number will also impact the result on required propulsive power; the higher the Froude Number, the greater the impact. Conversely, had these factors been reduced below the baseline values the impacts would have been reduced, vice increased, The maximum baseline Froude Number will also impact the results of required propulsive power. The froude number of the 2,000-tonne SLC coincides with the hump residual resistance. Therefore, the higher or the lower the froude number the less the impact. Addition of Superstructure Volume The results of adding superstructure volume to the 2000-tonne SLC at three different densities, 0.0, 0.164, and 0.268t/m³, were studied. The added weight located within the new superstructure was assumed to be located 3.89m above the Main Deck. In so far as feasible, the LBP of the hull was adjusted to ensure that:

Modified Deck Area = [Baseline Deck Area + Area Of the Added Volume] The impacts per m³ of additional superstructure volume are as follows:

Density of Added Superstructure Volume, t/m³ Item 0.0 0.164 0.268

Light Ship, including D&C Margin, t/m³ 0.0812 0.2902 0.4603 Fuel Oil Load, t/m³ 0.0037 0.0111 0.0179 Full-Load Displacement, t/m³ 0.0855 0.3029 0.4809 Propulsion Power, kW/m³ 2.630 9.7604 16.0570

Increasing the density of each m³ of added superstructure increases the impact on light ship, fuel oil and full load weight as well as increasing propulsion power. The above noted results reflect use of a relatively lightweight aluminum superstructure that has a structural weight equal to 0.0207t/m³. Changes in the structural density of the superstructure would have a proportionate impact on the above noted results. As before, the impacts would also be similarly influenced by the hull density, range and speed of the baseline hull.



Addition of Weight Within the Hull The impacts of adding weight within the hull of the 2000-tonne SLC were determined as follows:

Item Per Tonne of Added Weight

Light Ship, including D&C Margin, t 1.410 Fuel Oil Load, t 0.068 Full-Load Displacement, t 1.4867 Propulsion Power, kW 25.9608 Shipyard Recurring Cost, Fraction of Percent 0.0537

The added weight was located at the vertical centroid of the hull volume 0.634 times the average hull depth. As before, the results will vary depending on the baseline hull’s density, fuel weight fraction and maximum Froude Number. The above noted impacts will increase if the design being studied is denser and/or has more range and speed than the 2000-tonne SLC used herein. Conversely, these impacts will decrease if the hull has less density and/or the range and speed are less. Addition of Hull Volume The impact was determined of adding hull volume to the 2000-tonne SLC at three different densities, 0.0, 0.1339 and 0.2030 t/m³. In order to increase hull volume, the LBP was adjusted accordingly. The added weight was assumed to be located at 0.634 of the average hull depth, which is the approximate vertical centroid of hull volume. In so far as feasible, superstructure volume was adjusted to ensure that:

Modified Deck Area = [Baseline Deck Area + Area of the Added Volume] The impacts per m³ of added hull volumes are as follows:

Density of Added Hull Volume, t/m³ Item 0.0 0.1339 0.2030

Light Ship, including D&C Margin, t/m³ 0.1441 0.3073 0.3846 Fuel Oil Load, t/m³ -0.0038 0.0087 0.0202 Full-Load Displacement, t/m³ 0.1412 0.3179 0.4072 Propulsion Power, kW/m³ -4.2008 -3.7252 -0.9285 Shipyard Recurring Cost, Fraction of Percent/m³ -0.0015 +0.0060 +0.0065

As shown above, adding hull volume, which requires lengthening the hull, will increase weight, but can reduce resistance at high speed and even reduce the required fuel oil load. This occurs because increasing the hull length simultaneously reduces the displacement -to-length ratio of the hull (Displ./(0.1L)3 while slightly reducing the Froude Number at both the maximum and cruising speeds. Increasing length generally results in increased wetted surface and, hence, additional frictional drag. However, depending on the speed of the baseline and the density of the added volume, this can be more than offset by the reduction in residual resistance generated by the reduction in the hull’s displacement-to-length ratio and, to a lesser degree, by the small reduction in the hull’s Froude Number. As before, the results will vary depending on the baseline hull’s density, range and speed. Th e impacts will tend to worsen if the design being studied is denser and/or has more range. The impacts will tend to be reduced if speed (measured in terms of Froude Number) is more or less than the 2000-tonne SLC.



Figure 3.4-1 shows the light ship weight growth per cubic meter of added superstructure or hull volume at densities varying from 0.0 to 0.3 tonnes of added weight per cubic meter of added volume. Added weight represents the weight of dedicated equipment or systems directly associated with the added volume, not other weights impacted by the increased volume such as the weight of boundary structure, electrical power, lighting, HVAC, piping, insulation, painting, etc. This additional weight reflects the difference between the directly added weight and the total required increase in light ship displacement. At zero density, the required increase is about 0.085t/m³ for added superstructure volume. The required increase gets linearly larger to about 0.20t/m³ at a superstructure density of 0.3t/m³. As shown in Figure 3.4-1, at comparatively low densities, added hull volume has a greater impact than added superstructure volume. However, at higher densities, added superstructure volume has the greater impact. This occurs because of the impact of the high KG of the weight added within the superstructure. The change in KG increases the required hull beam. Increasing hull beam has a major impact on light ship weight.

0

0 . 1

0 . 2

0 . 3

0 . 4

0 . 5

0 . 6

0 0 . 1 0 . 2 0 . 3

H U L L

S U P E R S T R U C T U R E

A D D E D W E I G H T / A D D E D V O L U M E

L . S . W TC U . M .

Figure 3.4-1 Impact of Added Hull or Superstructure Volume Based on the results of this study, which used the low density, low range and moderate speed 2000-tonne SLC as a baseline, the total light ship growth per tonne of added weight will be as follows:

Location of Additional Weight Light Ship Growth

Per Tonne of Added Weight Below Weather Deck 1.41 Above Weather Deck 1.66 Within Superstructure @ 10m³/t 2.20 Within Hull @ 10m³/t 2.70

The data provided in Figure 3.4-1 can be used to study the impact of many types of changes in requirements. For example, consider adding one accommodation to the 2000-tonne SLC. This will require 10.33m2 of personnel-related deck area, plus a proportional increase in the deck area required for the HVAC, access, storerooms and margin categories. Assuming an average deck height of 2.6m, this results in a volume increase of 30m³. The directly added weight for furnishings and other associated personnel-related equipment would be 0.45t. Based on Figure 3.4-1, the impact of 30m³ of additional hull volume will be as follows:



Density = ³/015.0³30

45.0mt

mt

=

Therefore, @ 0.015t/m³, the impact will be +0.16 t/m³/accommodation or 0.16t/m³. 30m³ = +4.8 tonne per accommodation. The impact of dense accommodation-related loads, including stores, provisions, potable water, and crew and effects, can all be roughly treated as a zero volume weight increase. Therefore:

+1 tonne/accommodation x 1.4 tonne/tonne = +1.4 tonne/accommodation. The total impact of one additional accommodation will therefore be:

+4.8tonne + 1.4tonne = 6.2 tonnes/accommodation. For comparative purposes, it is also interesting to assess the results of the impact of a trade-off study of enhanced habitability for the 600-tonne SLC, as previously discussed in Section 3.3.4.3. In this trade-off study, habitability-related deck area was increased from 7.04 to 9.11 sq.m/accommodation. Therefore, the total volume increase was:

48 accommodations x 2.07sq.m/accom x 2.6m deck height = 258.34m³ and based on the impact of superstructure volume data provided in Figure 3.3-1:

Increase in Light Ship Weight = 258.34m³ x 0.085t/m³ = 21.96 tonnes. The actual trade-off study resulted in a calculated increase of 21.5 tonnes. This approach, therefore, provided a quick assessment of the impact of enhanced habitability within 2 percent accuracy. The data in Figure 3.4-1 provided reasonable accuracy because both the 2000-tonne and 600-tonne SLCs had generally consistent hull density, range and speed.



4.0 RULES AND STANDARDS APPLIED IN SMALL SHIP DESIGN 4.1 Introduction One of the major objectives of the ST-SSD was to examine and reach a common understanding of the rules and standards that are applicable to small ship design. The team addressed this by examining the relevance of existing NATO publications to small ships, examining the rules and standards currently in use by the navies and coast guards of the nations participating in this study, and by examining the recently published Naval Vessel Rules of several Ship Classification Societies. The team reviewed thirty-nine NATO documents applicable to small ships. Of the documents reviewed, seven were Allied Maritime Environmental Protection Publications (AMEPP), 15 were Allied Naval Engineering Publications (ANEP), and 17 were Standardization agreements. The details of this review are summarized in Section 4.2. In general, it was found that many of these documents are applicable, or partially applicable, to small ship design. However, many of these documents are outdated and in need of revision to reflect current developments and trends in naval ship design and operation. The study of the rules and standards employed in small ship design considered seven existing SLCs and six OPVs. The study included consideration of Classification Society Rules used in the design and construction of the ships, environmental regulations, requirements for personnel safety, seakeeping requirements, standards for specifying speed and powering requirements, maneuverability, accessibility requirements, survivability requirements, signature management, intact and damage stability, structural design loads and response criteria, and electric system requirements. Also, habitability requirements were considered. In general, it was found that many of the ships made use of Classification Society Rules for guidance in the design and construction; however, most nations did not class the ship with the Classification Society. Many nations also made use of the International Maritime Organization’s High Speed Craft Code. All of the ships considered comply with the International Maritime Organization’s MARPOL regulations. Most ships were designed to national safety regulations, although some ships were designed to either NATO ANEP 24, 25 and 26 or SOLAS requirements. Many nations employed STANAG 4154 for the specification of seakeeping requirements. Most nations utilized national standards for speed/power, maneuverability, vulnerability, signature management and stability requirements. The details of the study of standards and rules applied to small ships by each nation are addressed in section 4.3. The objective, with regard to the examination of Naval Vessel Rules, was to determine the overall impact these rules would have on ship cost, size and performance versus nationally-developed naval design criteria. To accomplish this, structural sections were developed. Additionally, HVAC, Firemain, Potable Water, and Fuel Oil Fill and Transfer systems and components were sized. Based on the structural sections and system data, estimates of the overall impact to ship size, performance and cost were made parametrically based on equivalent stability and range. The results of this study are addressed in section 4.4. 4.2 Review of NATO ANEPS and STANAGS The following documents (with brief descriptions of the document) were reviewed:

ANEP-11 Standardized Wave and Environments for NATO Operational Areas: No comments ANEP-11/ SUPP-1 Seasonal Climatology of the North Sea (5-Year Statistics): No comments ANEP-15 Supplement 1 to STANAG 4154 – General Criteria and Common Procedures for Seakeeping Performance Assessment – Fast Patrol Boat: This document is partly outdated (1988) and all the supplements to STANAG 4154 lack up-to-date references regarding current evaluation tools such as the last generation CFD codes, etc. This ANEP is recommended for updating.



ANEP-16 Supplement 2 to STANAG 4154 – General Criteria and Common Procedures for Seakeeping Performance Assessment – Mine Counter Measures Vessels: This document is partly outdated (1989). This ANEP is recommended for updating. ANEP-17 Supplement 3 to STANAG 4154 – General Criteria and Common Procedures for Seakeeping Performance Assessment – Hydrofoils: This ANEP is considered to be of little further interest (1990). ANEP 21 Procedure for Ship Manning for NATO Surface Ships: The purpose of the ANEP is to define a uniform methodology for determining manpower requirements in NATO surface ships. The methodology is general and written for all Surface Ships. Parts of the ANEP are not applicable for smaller ships. However, the procedure may be used for all ships (1991). ANEP 22 Human Factors Considerations for the Determination of Automation Policy: The purpose of the ANEP is to give designers of NATO Naval Weapon Systems an approach to handle automation planning. The approach is also applicable to smaller ships, both for weapon systems and ships management systems. Smaller ships will normally always have “lean” manning, and automation requirements will have to be addressed (1992). ANEP-24 Guidelines for Shipboard Habitability: The general approach is applicable for small ships as well. ANEP 25 Guidelines for Environmental Factors in NATO Surface Ships: This document provides definitions of design criteria to be applied in NATO surface ships. The ANEP is general and, in principle, also applicable for smaller ships (1991). ANEP 26 Ergonomic Data for Shipboard Space Design in NATO Surface Ships: General data for ergonomic design in NATO surface ships. This ANEP may drive the design of smaller ships. The ANEP is general and, in principle, also applicable for smaller ships (1993). ANEP-41 Ship Costing: The general approach is applicable for small ships. ANEP-43 Ship Combat Survivability (NATO Confidential): The general methodology appears to be applicable to small ships. The recommendations are probably less applicable, as they are tailored for frigates/destroyers. ANEP-46 STANAG 4154 Supplement – List of References on Seakeeping Performance Assessment: This document is partly outdated (1995). The internet may have outdated such a publication. This ANEP is considered obsolete and is recommended for termination. ANEP-47 Guidelines for Developing Criteria for Surface Effect Ships Seakeeping Performance Assessment, supplements 1, 2 and 3: This document is outdated (1995) and is recommended for updating. ANEP-49 Ways to Reduce Costs of Ships: The general approach is applicable for small ships. ANEP 52 The Application of Costing and Operational Effectiveness Methods for the Selection of Hull Types: This document contains methodology for planners and designers for the selection of hull types for particular military roles. This 1997 ANEP remains directly applicable for smaller ships. STANAG 1008 Characteristics of Shipboard Electrical Power Systems in Warships of NATO Navies: The aim of the 1994 STANAG is to provide common characteristics and operational compatibility between warships within NATO. General and applicable also to smaller ships.



STANAG 1065 (ATP 16 (D)) Replenishment at Sea: This document includes operational and technical procedures, rigs and equipment to use when refuelling. Methods used include astern refuelling. The document is considered to be applicable to smaller ships. STANAG 1136 Standards for Use When Measuring and Reporting Radiated Noise: This document discusses the characteristics of surface ships, submarines, helicopters, etc. in relation to sonar detection and torpedo acquisition risk. The terminology, units, standards and procedures are applicable to smaller ships (1995). STANAG 4141 Shock Testing of Equipment for Surface Vessels (NATO Restricted): This document addresses common procedures for shock testing of equipment in all ships. Smaller designs will normally have reduced survivability requirements. However, the 1976 STANAG is general and can be applicable to smaller ships. STANAG 4142 Shock Resistance Analysis of Equipment for Surface Ships (NATO Restricted): This document addresses common procedures for shock analysis of equipment in all ships. Smaller designs will normally have reduced survivability requirements. However, the 1977 STANAG is general and can be applicable to smaller ships. STANAG 4154 Common Procedures for Seakeeping in the Ship Design Process: This is a fairly new document and provides general guidance. STANAG 4194 Standardized Wave and Wind Environments and Shipboard Reporting of Sea Conditions: This document contains very little information on littoral waters. However, limited data is provided for the North Sea, Baltic Sea and Black Sea. STANAG 4293 Guidelines for the Acoustical Environment in NATO Surface Ships: This 1990 document addresses criteria for specifying acoustical requirements for all surface ships. It remains applicable to smaller ships.

4.3 Rules and Standards Applied in Small Ship Design – Top Level Comparison The aim of the study was to clarify the present rules and standards used in small ship design in various countries and to study possible differences in the rules applied in OPV and SLC new construction. Also, the rule status was studied, i.e. if the ship were to be built today, would the same rules and standards be used? The study results are presented in Appendix 9.5. The data sheets for the various ships have been included in Appendix 9.6. Information on seven existing SLCs and six OPVs from 11 countries have been included in this study. These ships are identified in Table 4.3-1.



Table 4.3-1

NATO Small Ships Considered in Standards/Rules Comparison

Small Littoral Combatants: Nation Vessel Type Data sheet Finland FAC Hamina Class Enclosed Missile boat Greece Gunboat of Pyrpolitis - Class Norway Royal Norwegian Navy Enclosed FPB Skjold Class Missile Boat Sweden Visby Class Enclosed Corvette Ukraine Ukrainian Navy - Corvette of “Grisha-V” Class (Displ=920 t) Turkey Corvette - Turkey Firkateyn - Offshore Patrol Vessels: Canada Multipurpose Offshore Enclosed Patrol and Route Surveillance Mine Countermeasure vessel Italy Sirio Class Enclosed (NUPA Class) Netherlands Netherlands Coast Guard Cutter, Enclosed design Damen Stan Patrol 4100, specification dated 30 September 1996 Ukraine OPV (Displ=890 t) proposed - for the Ukrainian Coast Guard United Kingdom UK River Class OPV Enclosed United States United States Coast Guard Enclosed Coast Guard FAMOUS Class 270-ft Medium Endurance Cutter



The following results were drawn from the comparison of Rules and Standards:

• International shipping standards (Class/IMO, etc.) have generally been used for many structural parts of the ships. Many new ships have been built “according to class requirements, but not classed”. A full class notation, however, is not a common practice in these ships.

• MARPOL rules have generally been obeyed as environmental regulations. • The NATO STANAGS have commonly been used as standards for:

- seakeeping - acoustic and magnetic signatures - shock - electrical

• National rules have been widely used for habitability, maneuverability, accessibility, radar cross-

section, infrared signature, etc.

• There are no significant differences in the rules or standards applied to SLCs and OPVs, although some of the military requirements are, of course, not applicable to OPVs.

It should be noted that the ships included in the study were built before the publication of Classification Society Rules for Naval Ships. There seems to be a trend to apply these to future designs, although their value and applicability is still to be evaluated. There is also pressure to introduce naval SOLAS rules, which would be used for SLCs. 4.4 Review of Classification Society Rules for Naval Ships Current structural rules for naval ships issued by three major classification societies were applied to the notional 2000-tonne SLC presented in section 3.2.5. The rules investigated were:

• ABS Guide for Building and Classing High Speed Naval Craft, 2003, Part 3, Chapters 1 & 2. • DNV Rules for Classification of High Speed, Light Craft and Naval Surface Craft, July 2002, Pt.3. • LR Rules and Regulations for the Classification of Naval Ships, January 2002, Vol. 1, Parts 3-6.

In addition, U.S. Navy Rules DDS-100-4 and DDS 100-6 were used as reference points where applicable. The general characteristics of the 2000-tonne SLC design used for this study, and some specific details needed for the structural calculations performed, are provided in Table 4.4-1.

Table 4.4-1

Principal Characteristics of Vessel Used for Comparative Calculations

Characteristics SLC LBP x BWL x D x d, m 93.9x13.2x9.1x3.8 Displacement, total / molded; tonne 2465 / 2380 CB, CW, CM, 0.495; 0.799; 0.798 Maximum sustained speed, knots 29.2 Regional and Sea State restrictions No restrictions Yield stress of steel used for deck/bottom; other; Mpa

325; 235

Deadrise at LCG / 0.2L bottom / 0.2L bow, degree

13 / 27 / 60

WL entry angle at FP, degree 15 Spacing of deck/bottom longitudinals; floors/web frames; cm

46; 203



The rules were applied to obtain the design global loads on the hull girder and to calculate the required hull girder section moduli. The plate thicknesses for major shell plating members subjected to primary and local loads were also calculated. The rules’ requirements were applied directly, as in the rulebooks, without using any of the classification software developed by the societies for advanced calculations of the design loads and required scantlings. In all of these rules, the still water and wave-induced vertical bending moments and shear forces, as well as slamming moments and shear forces, are identified as the only global loads. The horizontal wave-induced bending moments are not accounted for in these rules explicitly, but some factors in the formulations may suggest that implicit considerations were given in specifying the vertical wave-induced bending and slamming moments. The results in Table 4.4-2 show that the still water and wave-induced bending moments, as determined by these rules, vary by as much as 20-25%. However, the difference in the slamming moment is very dramatic, varying as much as 500%. This huge difference is partly due to very complicated formulations for the slamming areas and pressures in LR and DNV Rules. These rules require extensive input data for the hull lines and are very sensitive to abrupt changes in the lines. Such changes are typical for high-speed ships, especially in the stern areas. Even with the complicated formulations, it is not always possible to properly address the specifics of ship geometry. The relatively simplified ABS formulations are less sensitive to the specifics of the lines. It should be noted, however, that in spite of such dramatic differences in the slamming loads, the resulting design loads in ABS and LR Rules are very close to each other (usually less than a 10% difference). However, the rules are almost uniform in determining the allowable stresses for global loads, which are much higher than those permitted by the U.S. Navy.

Table 4.4-2

Design Global Moments in MN*m, Specified by the Rules

ABS DNV LR Vert. Wave BM, sag -120 -161 Vert. Wave BM, hog 96 86 SWBM, hog 72 48 42*,

assmd Vert. SW+Wave BM, sag 147 Vert. SW+Wave BM, hog 130 Slamming BM, crest-DNV, others unspec.

215 423 83

Rule Vert. Wave BM 215 204 Extreme Vert BM 241 Allowable stress for deck/bottom, MPa

224 224 231

* assumed as 0.5WBM The required section moduli and scantlings of main hull girder members and local structures do not differ dramatically between ABS and LR Rules, and corroborate reasonably well with the U.S. Navy -based best practice results, though the calculation procedures in ABS and LR Rules are sometimes considerably different.



5.0 SMALL SHIP DESIGN, ACQUISITION AND SPECIFICATION 5.1 Introduction NATO member and Partner for Peace nations employ a variety of ship design and acquisition strategies. This section examines the ship design and acquisition strategies in use by each nation and introduces a specification that can be tailored for use in any of the acquisition strategies employed. Generally, all nations utilize the same ship design process which consists of four phases: 1) Pre-feasibility; 2) Feasibility, Conceptual and Preliminary Design; 3) Contract Design; and 4) Detailed Design. The biggest difference in each nation’s design process is which phase of the phases of the design are accomplished within the government and which are contracted out to the shipbuilder. This decision directly influences the type of specification utilized for the ship acquisition. For design efforts that are contracted to the shipbuilder early in the design process, high-level guidance is usually provided from the government in the form of a performance specification. Design efforts that are developed to a high degree of fidelity under government control usually result in the government issuing a design specification. The ship specification template provides a guide from which either a unique performance specification or design specification, or both, can be developed. It is anticipated that if a rigorous system-engineering process is employed, both a performance specification and a design specification will need to be developed before construction of the ship can begin. 5.2 National Design and Acquisition Processes 5.2.1 Netherlands The procurement process of the Royal Netherlands is based on the NATO Phased Armaments Programming System (PAPS). More specific to the Dutch situation, however, are the four so-called “main gates”. “Main Gates” are linked to the phasing of the procurement process before contracts for each delivery or construction phase can be signed. Depending on the financial scope of the project or on the degree of political sensitivity, each “main gate” may require political approval before the implementation of the next phase. In principle, for large naval projects (frigates, AORs, LPDs), approval is required for all phases. In specific cases, the project can be finalized by an Evaluation Report. The report traces the responsibility with respect to the quality of the new material, the construction cost, project experience, and any recommendations for future projects. The RNLN procurement process was introduced in 1984 by ministerial designation. This ministerial designation is re-evaluated every five years and functions up to the present day, albeit in a slightly modified form since its introduction. For political reasons, the need arose for information regarding the progress on a more frequent basis rather than at the end of every phase. Thus, policy-makers now receive a monthly update on the status of each major project. For the procurement of navy ships, the RNLN is one of the last NATO members which still retains an in-house design capability. This in-house capability provides the RNLN with the ability to develop independent design studies, concept designs and preliminary designs in support of the acquisition process. Additionally, the RNLN itself procures all the weapons, sensors and communication systems (SEWACO) and is responsible for the system integration thereof on the platform design. By utilizing the Centre for Automation of Mission-critical Systems (CAMS), the RNLN retains the ability to develop and maintain the Combat Management Systems software of all their own ships. Therefore, during the procurement process, the RNLN remains responsible for the execution of major parts of the project. With regard to the design of military capabilities (i.e. signatures, vulnerability, and platform management), the RNLN also has the necessary military-maritime knowledge and experience in-house to carry out portions of the detailed design which can then be supplied to the yard after contract award.



For research, the RNLN is supported by well-known R&D institutes (TNO, MARIN) and universities. Another important aspect of the marine shipbuilding industry in The Netherlands is the Royal Schelde in Flushing. This is the only shipyard that builds naval ships in the Netherlands. Special procedures are used to assure that contracts are competitive, fair and reasonably priced. An open cost calculation, including all quotations from subcontractors, has to be provided to the National Defence Accountancy for approval. Also, in-house experts on ship costing are used to validate technical parameters used by the shipyard. 5.2.2 United States Navy/Coast Guard The United States Coast Guard and Navy procure ships in accordance with DOD Directive 5000.1. One of the fundamental principles behind DOD Directive 5000.1 is to “maximize competition, innovation, and interoperability and to enable greater flexibility in capitalizing on commercial technologies to reduce costs”. This is accomplished by relying on performance-based acquisition strategies for all new procurements, major modifications and upgrades. This requires that contractual requirements be stated in performance terms and that the use of military specifications and standards be limited. Within DOD Directive 5000.1, there is no suggested best way to structure the acquisition program. Program managers are allowed to tailor the acquisition strategy to fit the particular conditions of an individual program. However, this strategy must be consistent with common sense, sound business management practices, and applicable laws and regulations. What this means for shipbuilding programs is that, for the most part, the traditional four-phase ship design process (Feasibility and Conceptual Design, Preliminary Design, Contract Design and Detailed Design) is retained. However, the shipyard still performs most or all of the design phases, with the shipbuilding contract generally awarded after the completion of an “in-house” Government developed Conceptual or Preliminary Design. The contract requirements issued by the government for performance-based ship acquisitions makes the contractor accountable for total ship performance and usually consists of a statement of objectives defining the anticipated scope of work and a performance specification. The performance specification describes the total ship, its systems and its equipment in terms of required/desired performance. The performance specification also provides requirements for verification of performance, defines interface requirements, and describes the environment in which the ship must operate. 5.2.3 Turkish Navy Staff Requirements are first defined in the Mission Definition Document for the Project. After pre-feasibility studies, and in conjunction with the development of the Mission Definition Document, a Technical Definition Document (TDD) is prepared by taking into account several alternative technical configurations. Based on the TDD, a Technical Specification Document (TSD) is prepared. The Project is put out to tender by a Request for Proposal (RFP), which includes the TSD and Administrative Specification Document. After the bids are received, the evaluation process starts. The company whose offer is determined to be the best technical-economical offer is awarded the prime contract. There are three different organizations responsible for managing the procurement process, depending on the characteristics of the acquisition program: the Navy, the Ministry of Defense Foreign Procurement Department/Domestic Procurement Department, and the Undersecretary of Defense Industry. The funding may be obtained from three different sources. The first is the National Budget, second is the Defense Industry Support Fund, and the third is the Government-Company Credit (i.e. credit provided by the Contractor under the payback guarantee of the Turkish Government). The payment method varies among contracts, depending on the type of project and the funding. One method is to pay a portion of the contract in advance and the rest by installments. In some situations, the payments are made in accordance with milestones and in others upon actual delivery. Most contracts are fixed price, however, in some cases, escalation may be factored into the fixed price.



5.2.4 Portuguese Navy The legal framework for the significant naval acquisition process is provided by the law/decree nº 33 of 5 February 1999, which states: “The rules of the EC directives 93/36/CEE and 92/50/CEE do not apply to contracts referring to the acquisition of weapons, ammunition and other military equipment, mentioned in the paragraph 223, nº 1 b) of the Treaty of Rome. The absence of these rules may cause a lack of transparence in the acquisition processes of defense equipment by government agencies, which is in itself unacceptable, and lead to the establishment of several different acquisition rules and processes within the government. This diploma defines the procedures to be adopted by all government agencies in this matter; however, for low cost acquisitions the general legal procedure for the procurement within the government may be used. It is recognized that, for very high cost acquisition processes, public tender isn’t always the most adequate procedure in order to insure that national defense is well served. This is because public tender tends to be a very formal form of procedure with difficulties to accommodate extensive negotiation with the tender bidders, which is often of the highest importance to insure that the final goals of the acquisition process will be met under a reasonable cost and time frame. However, public tender may be considered to be the most adequate form of procedure for a given acquisition process, and therefore it may be used instead of the option presented in this diploma. The procedure of tender with previous selection of the bidders’ proposals, approved by this diploma, may be initiated by a public announcement or by means of direct invitation to, at least, three potential bidders considered to have the capacity to meet all the contract requirements. On the other hand, this procedure enlarges the extension of the process leading to the generation of the proposals and subsequent negotiation process. Therefore, in this procedure it will be mandatory for the government agency responsible for the acquisition process to produce one Program of the Tender (description of the tender procedure) and one Checklist of Tender Requirements (all the items that the bidders should address in the tender, counterparts to be offered, economical compensations, and issues beneficial for the Portuguese economy, when applicable). It was also considered to be necessary to establish mandatory rules for the act of publication of the bidders proposals. This should be a solemn act, similar to the procedure of public tender. In addition, and in some form of opposition to the public tender procedure, this new procedure includes one stage of negotiations, just after the selection of a limited number of bidders, and this should contribute to a considerable improvement of the final bids. This is the innovative aspect of this diploma, as in the other aspects the general rules for acquisition within the government agencies are used. The selection of the procedure remains under the responsibility of the government agency involved, except if the procedure is the Direct Negotiation with one single bidder. In this situation, the intervention of the Minister of Defense and the Prime-Minister is required.”

5.2.4.1 Procedure This diploma establishes the legal frame for the acquisition processes under the paragraph 223, nº 1 b) of the Treaty of Rome; it is applicable to acquisition processes for the Ministry of Defense and agencies under this Ministry, and it may be extended for use by the security forces when the acquisition process is developed by the Ministry of Defense.



The procedure is initiated by the publication off an announcement in the “Diary of the Republic” (the official publication of the Portuguese legislative authority) and at least two national newspapers, or by direct invi tation to at least three potential bidders. The documents (the Program of the Tender and the Checklist of Tender Requirements) are prepared; a jury (with and odd number of members and one) is given the responsibility for the momentum of the process. A technical committee is usually added to the jury (under the jury’s authority) to assist in the technical documents, in inspection during the construction’s stage and trials. The bidders proposals are analysed, and a number of bidders are selected for the negotiations phase. After negotiations, the jury prepares a report, which is public for all bidders; the bidders may argue against the report and it’s recommendations and only after an extensive analysis of all the bidder’s arguments the contract is signed. The same jury is responsible for the inspection during construction and acceptance trials, but usually the technical committee does all the work; the technical committee is always made of people closely connected to the end user (for example, in the case of a naval construction, the technical committee will be made of naval officers, mainly engineers and naval architects), so that in the period of guarantee after acceptance trials, the technical committee will also be linked to the process.

5.2.5 Italian Navy There are eight phases to the acquisition process: Phase 1- Promulgation of a document called Operational Requirement that gives an indication of

the operational capabilities for the new ship. Phase 2- After an internal staffing process, a new and more detailed document is written. It is the

so-called DISOG, the Operational Specification. Phase 3- A pre-feasibility study starts on the basis of the Operational Specification. This phase is

an internal one, as the Italian Navy has an in-house design capability. Phase 4- At the end of the pre-feasibility study, a first draft of the Technical Specification is written.

This is a document that outlines the ship to be built in all aspects, both for the platform and for the combat systems. During this study, the Navy can outsource some activities for support.

Phase 5- This phase consists of an evaluation of the technical feasibility of the project. If this

phase results in a negative answer, the process must start over with a less demanding DISOG. During this phase, the shipyard is usually involved and there are some technical discussions about the project.

Phase 6- If the technical feasibility is verified, the evaluations of the economic viability of the project

begin. If it is determined that the project is too costly, the process must start over with a less demanding DISOG.

Phase 7- On the basis of the Technical Specification, which at this time is a definitive and official

document, the Directorate for Naval Procurement starts to prepare the Contractual Specification and a first draft of the Contract.

Phase 8- During this last phase, an RFP is issued and negotiations between the Navy and the

Shipyard begin. If the negotiations are successful, a contract is awarded. Otherwise, the process must start over again from Phase 1.



Phases 1 to 4 are the responsibility of the General Staff. Phase 5 is a joint effort between the General Staff and the Directorate for Naval Procurement. Phases 6 to 8 are the responsibility of the Directorate for Naval Procurement, obviously supported by the General Staff. 5.2.6 Norwegian Skjold Class FPB Acquisition Process The initial staff requirements were first issued in 1986. Based on the initial staff requirements, NDLO/Sea (Norwegian Defence Logistic Organization/Sea – formerly Naval Material Command Norway), together with COMSEATRAIN, conducted several feasibility studies to find a balance of the operational solutions with the budget requirements. Initially, ten different platform solutions were studied in 1990. Based on these studies, it was concluded that three different concepts were feasible: a Monohull, a Catamaran, and a Surface Effect Ship (SES). Due to the requirement for high speed (44 knots in SS3) in conjunction with the need for a stable platform and good seakeeping capabilities, the SES concept was selected in 1994. This was a controversial choice at the time, as many people wanted a simpler and more proven concept to be chosen. The initial design work was conducted by Cirrus in Bergen, Norway. NDLO/Sea and the consulting firm LMG Marin in Bergen developed the design further. The design was developed to the point where NDLO/Sea had confidence in the selected main characteristics for speed, weight and strength. Through this process, the main dimensions, the General Arrangement, and the feasibility of the design were determined. The Norwegian navy took the design further than normal in this case to reduce the risks for itself and a potential supplier, and to ensure the viability of the concept. Negotiations for the contract to build the prototype vessel were started with two Norwegian yards. The yards were also invited to present changes and alternate solutions to the design as presented by NDLO/Sea. The contract covering detailed design and construction of the prototype vessel, including an option to build up to seven FPBs, was awarded to UMOE Mandal (then Kværner Mandal) in August 1996. In the contract with UMOE Mandal, NDLO/Sea was responsible for speed and seakeeping, EMI/EMC, signatures, and all general arrangements that were directly dependent on functionality, the last a rather unclear responsibility! Because of the early work with these issues, the risk connected with this responsibility was considered manageable in addition to reducing cost. The success of the ship also proved these qualities to be well taken care of in the design. HNoMS Skjold was commissioned April 17, 1999, and has undergone comprehensive testing for approximately two years before the decision to build five more ships was taken in June 2001. Procurement of these ships was planned for the autumn of 2002. 5.2.7 Finnish Navy The decision to execute a naval ship procurement program is based on the long-term strategic development plan which describes the capabilities the navy has to have within a certain time period. The Materiel Division of the Naval Headquarters is given a budget and the authority to procure the capability. The procurement is conducted under national commercial regulations to assure fair competition and to include enough Finnish industrial participation to create an in-country life-cycle support capability.



In most cases, a project team is formed for each project. Depending on the ship type, representation of various specialist areas, as well as maintenance, are included on the team. Operational requirements and user requirements are prepared in close cooperation with the project team. Research tasks are typically started a few years before procurement by Finnish research institutes and universities. The research is usually lead and financed by the Naval Headquarters. R&D tasks concerning special military capabilities, such as signatures and vulnerability, are conducted in-house by the Naval Research Institute and Naval Headquarters. The actual ship design spiral is started with several alternative solutions. Preliminary designs and feasibility studies are conducted. At this stage, an integrated project team (IPT) can be formed of Finnish naval architecture consultants, research institutes and industry. Requests for information (RFI) are also published in order to inform all the interested parties and to include all the feasible solutions in the evaluation. The pre-design phase is finalized to the level of an RFQ specification, including a requirement specification and usually one example design. The IPT is broken up at this stage. The RFQs are sent to several potential shipyards and systems manufacturers who have been “shortlisted” from the RFI feedback process. The preference is to find one prime contractor; however, in practice the vessel and the systems have been procured separately due to commercial, schedule or political reasons. The Naval Headquarters is responsible for integration with the help of industry.

Other factors that are part of the process include: 1. Detail design is carried out by the shipyard which has been awarded the contract.

2. The ships are designed according to classification society rules, but are not classed. This may change in the future.

3. Design reviews, as well as on-site inspections, are conducted by the project team and the inspection team.

4. The first crew of the ship is closely involved in the harbor acceptance trials as well as the sea trials.

5. When the shipyard delivers the ship, it is handed over directly to the end users.

6. If the yard is not a prime contractor, the sea trials for the weapons, sensors and communications systems continue under the lead of the Naval Headquarters.

5.2.8 Ukraine The Ukraine has inherited its design and acquisition practice from the former USSR. Its main distinctive features are as follows:

1. The main targets for new construction are set by long-term and medium-term programs approved by the Government in accordance with the needs of Naval (or political) Policy.

2. The work on a new ship starts with a research phase, which is based on the results of on-going

investigations in the area of naval shipbuilding. The goals of this research program are:

• Definition of requirements for future vessels in accordance with Navy needs. • Development of vessel's operational scenario for combat and peacetime employment. • Development of a life-cycle model. • Estimation of economical and industrial aspects of vessel's creation and maintenance.

The output of this phase is the so-called "tactical-technical task" which contains high-level requirements describing the ship's characteristics and payload. In the USSR, the research phase was fulfilled by Naval agencies with the participation of industry research organizations.



3. Tactical-technical task forms the basis for the draft design that is developed by industry based on

a contract awarded by the MoD. The goals of this phase are:

• To assess the viability and compatibility of tactical-technical task requirements. • To develop several concepts for the vessel, each with a different degree of compliance with

initial requirements, and to identify the most suitable solution. • To confirm the produceability of the vessel and the ability to maintain the vessel combat

readiness. • Estimation of military and economical expediency of further work. The output of this phase is a set of documents describing all of the studies and designs that were evaluated, including the Specifications that contain designer's contractual obligations. The Navy representatives supervise development of the draft design.

4. An approved draft design forms the basis for the preliminary design, which is also developed by

industry based on a separate contract awarded by the MoD. The goals of this phase are:

• To confirm and finalize the main particulars and characteristics of the ship. • To finalize technical decisions for all areas of the design. • To resolve all problems connected with the manufacturing process. • To develop a complete set of drawings and specifications needed for detailed design.

Among other tasks, the designer of the ship is also liable for weapon and electronics integration. Navy representatives supervise development of the preliminary design. Results of the preliminary design phase are approved by the joint decree of MoD and industry Authorities, which is a milestone for the beginning of the ship's construction.

5. The contract for the ship's construction is awarded by MoD to the selected shipyard. A design

organization, acting as a sub-contractor, develops the detailed design, trial and maintenance documentation. The task of the shipyard is to supply the ship that meets all of the requirements stated in the approved Specifications. The scope of delivery includes the completely equipped vessel with spares, but without ammunition. The maintenance is also included, but only during the warranty period. In the Ukraine, all research and design stages (phases) are conducted by the State Research & Design Shipbuilding Center. Navy institutions act as sub-contractors in the first (research) stage. However, the Ukraine has expressed an interest in strengthening cooperation with NATO. Any such transition to NATO standards will affect the existing national design and acquisition practice.

5.2.9 Polish Navy The purchase and supply process for Polish Navy ships is based on legal policy that concerns the Polish Armed Forces Modernization Plan for years 2002 – 2008. Based on this plan, which results from the country’s defense needs and alliance obligations, the detailed development program of the Polish Navy is developed. The development program takes into consideration current, annual state budgets and the political situation, as well as conditions and methods for financing the project. The main evaluation criteria for design solutions are cost (tenders, innovation of solutions, minimalization of costs, etc.) and combat capability (interoperability, flexibility, reparability, low vulnerability, etc.). Each program is tailored to a particular acquisition strategy for the budgetary process, standards, regulations



and laws. Combat and auxiliary ships are purchased based on a competitive contracting process with contractors in order to obtain the “best value”. Project documentation for the Polish Navy contains four principal design areas: Feasibility Design (studies, analysis, etc.); Conceptual Design, Preliminary Design or Definition Phase; Contract (technical project) Design; and Detailed (Working Project) Design. The design is carried out by design offices in shipyards or other organizations. The meritoric base for the contract is the technical specification and several documents of Contract Design. The shipyard which offers the best technical-economical proposal is chosen as the prime contractor. The Polish Navy co-operates with, and is supported by, several R&D (research and development) institutes, technical universities and the naval academy. In Poland, the following organizations are responsible for the acquisition process: Navy, Defense Foreign Procurement Department, and Defense Political Department, which are all under the authority of the Undersecretary of MOD. 5.2.10 Swedish Navy New ship construction is governed by the ”Material Plan”, which describes what to build, install and modify within the Navy for a ten-year period. This plan is updated once a year. The plan is based on the near-term and long-term development of the Swedish defense requirements and budget. At the beginning of a new project, a working group is established at Navy Headquarters to write a Preliminary Tactical, Technical and Economical specification (a Swedish TTEM) which is handed over to the Defence Material Administration, (FMV). FMV starts a pre-feasibility study of alternative ship designs with different capabilities and cost. A pre-feasibility study group is established for each separate project. Often, this pre-feasibility study is conducted in cooperation with industry in order to acquire the best technology in the country. FMV presents the alternative to the Navy Headquarters, which chooses one or more alternatives to proceed with. After this, another set of design studies refine the selected designs. FMV, again, presents the alternatives to Naval Headquarters, only with more accurate costs and detail information. When the pre-feasibility study is handed over to the Headquarters working group, a Final Tactical, Technical and Economical specification (STTEM) is written. The STTEM is then handed over to FMV and the writing of a technical specification starts with input from the feasibility study. After the technical specification is completed, the acquisition process starts and industry is able to offer proposals for the ship and equipment to FMV. The shipyard and other industries carry out the detail design with approval from FMV. The preference is to find one prime contractor, although in the case of the Visby Class, FMV was responsible for integration, with help from industry. 5.3 Standardized Specification 5.3.1 Introduction A specification is the interface document between what is actually needed (problem domain) and the actual resulting solution (solutions domain). This can be seen in Figure 5.3-1. Shipbuilding specifications are used to describe the engineering solution for a ship capable of meeting a set of predefined performance requirements. Due to financial constraints, however, it becomes more and more important for naval architects to prove that the ultimate result will be the best, most cost-effective ship possible. Despite the importance of finding new technologies and innovative solutions to meet the operational requirements, a total-system approach should be considered to assure that the resulting performance of this solution is the best compromise to fulfil the mission. This means a total-system approach is needed. This approach not only uses design methods and technologies to find the best solution meeting the operational requirements, but also includes the decision



process on how the operational requirements are related and defined in the context of the missions to be carried out. The ship’s performance may be exactly what the designers and manufactures intended. The ship’s effectiveness in the actual mission, however, is the degree to which that level of performance is suitable for supporting the design solution, and thus its effectiveness could still be low. This can be seen in Figure 5.3-2. The performance or capability of a system results from the particular way the system is designed and, therefore, reflects the properties of the system. When it comes time for the system to do whatever it is supposed to do, the performance becomes the input to that operation. The effectiveness is inherent to the mission and external to the ship. Effectiveness expresses what the operational situation requires of the ship, irrespective of the capabilities the particular ship may bring into that operational situation. The ship’s effectiveness has to do with the change in military situation that results from its involvement in the operational situation, which can be seen as output.

NEEDS

SYSTEMREQUIREMENTS

SYSTEMSOLUTIONS

PROBLEMDOMAIN

SOLUTIONSDOMAIN

Figure 5.3-1. Needs versus System

Requirements

MISSIONS

CAPABILITIES

TECHNICALREQUIREMENTS

SYSTEM REQUIREMENTS

SOLUTIONS Properties

Performance

Effectiveness

Figure 5.3-2. Total-System Approach

An important effect of total-system design is that the process that sets the system requirements is part of the total design process and should be free to change until the ship design itself is finalized at a conceptual level of detail. In the past, much discussion and effort has been directed at ways of reducing the costs of naval ships. These discussions have focused on ways of improving the efficiency of the designs, reducing manning, making ships more producible by shipbuilders, and improving the accuracy of the ship cost estimates so as to reduce the margin needed for uncertainties. But, by far, the most effective way of reducing ship cost is to make sure from the outset that nothing goes into the ship design that is not absolutely required for its successful operation. That process starts with getting the mission requirements right so no unneeded capabilities are provided in the ship. Modelling and simulation are the primary means for “designing” the most effective set of performance requirements. 5.3.2 Scope The ship specification template was developed assuming a systems engineering approach would be utilized to define customer needs and required functionality; document requirements and then proceed with design synthesis and system validation. This process would lead to a flow down of high level system



requirements (performance specification) to subsystem and component level requirements (design specification). The ship specification template is provided in Appendix 9.7 and is divided into two parts. The first part of the template is for the development of a performance specification. The performance specification template is intended to describe the total ship, its systems and equipment in terms of required/desired performance, provide requirements for verification of performance, provide ship interface requirements, and describe the environment in which the ship must operate. The second part of the template is for the development of a design specification and is organized using the NATO ship work breakdown structure. It is intended that this part of the specification address technical requirements and information relating to the construction of the ship and information defining the work and responsibilities required of the shipbuilder for designing, building and equipping the ship. It is intended that this portion of the specification template would address general and specific features, functions and arrangements of the ship as a whole, and the various systems and components to be installed. It is also intended that this part of the specification include design criteria, standards and acceptable solutions for meeting performance requirements. 5.3.3 Organization Part one of this specification template is organized based on a tiered structure that addresses the concept of operation for the ship, the range of anticipated uses of the ship and its onboard systems or components, the utilization environment, events to which the ship must respond, physical and functional interfaces, system end product functional requirements and how often the end product will be used. Part two of this specification is organized in accordance with the NATO Ship Cost/Work Breakdown Structure (Level 3), which is a comprehensive framework which can be used throughout the entire life-cycle of the ship, from early design and cost studies through production and subsequent disposal, and into which can be organized and correlated elements for cost, weight, ship production and maintenance. All classification groups in this section of the specification have been defined by basic function, i.e. ship structure, systems, machinery, armament, outfitting, etc. There are ten major groups as follows: 000 General Guidance and Administration 100 Hull Structure 200 Propulsion Plant 300 Electric Plant 400 Command and Surveillance 500 Auxiliary Systems 600 Outfit and Furnishings 700 Armament 800 Integration/Engineering 900 Ship Assembly and Support Services



6.0 SMALL SHIP TECHNOLOGY 6.1 Mission Modularity 6.1.1 Introduction In general, large combatants such as frigates, destroyers and cruisers are designed for multi-mission scenarios in a medium or high-threat environment. As a result, these ships become highly sophisticated and, therefore, extremely expensive. As the execution of Peace Support Operations is now a dominant task for navies, the use of such ships can be inefficient. Smaller ships with limited, but specific, capabilities could be a more cost-effective solution. Asymmetric warfare in a littoral environment is also opening the way for SLCs to play a key role as nodes in a wider “netted” force with the recent emergence of network-centric warfare concepts. Smaller ships with fixed systems and limited capabilities provide little platform flexibility. Since the specific capabilities related to Humanitarian Assistance and Peace Support Operations can be difficult to accommodate on small platforms, other solutions are needed. One possible solution could be the development of a fleet based on dedicated ships optimized for specific tasks. This would lead to a need for a large number of specialized ships. However, both the development and in-service costs strongly favor limitation of the number of ship types or platforms within the fleet. This is where mission modularity can be a benefit. This section describes what Mission Modularity is and why, when and how such a solution should be taken into consideration.

Figure 6.1-1. Blohm + Voss MEKO Concept 6.1.2 What is Mission Modularity? Mission modularity refers to the reconfigurability of the ship. Task-related equipment modules; manned or unmanned off-board vehicles; task-related manning detachments; or a combination of all these elements could be used to adapt the ship to the demands of specific missions. However, mission modularity still affects operational flexibility during the mission. Both the time and the logistics required to reconfigure the ship have to be taken into account. This might result in unacceptable consequences for mission employment. It also emphasizes the need for more accurate configuration management.



An answer to this is an accurate mission analysis in the early stages of the design. This would also underpin the decision process on the cost-effectiveness of such a concept. As such, mission modularity is not just an alternative technical solution. It results in a totally different operational fleet concept that, as an option, needs to be carefully analyzed during very early design stages.

Figure 6.1-2a. Standard Interface STAN FLEX Container

Figure 6.1-2b. STANFLEX Container Figure 6.1-2c. STAN FLEX Module Placed Onboard for 76mm Gun

6.1.3 Applications In the past, modularity has been successfully applied to naval ship design. The application, however, was mainly focused on flexibility and standardization, and the advantages thereof for the engineering and construction of new naval ships. For that reason, the Blohm +Voss MEKO-Concept, developed in the early 80’s, was and still is a very successful concept. The MEKO-Concept provides a range of choices in the selection of onboard systems. Standardized modules for weapons, electronics and ship’s technical equipment are connected with the ship’s power supply, air-conditioning and ventilation system, and data network using standardized interfaces (Figures 6.1-1a, 1b and 1c). By simultaneously building the ship’s platform at the yard and the modules at the suppliers’ premises, a significant saving in both time and cost can be achieved (see Figure 6.1-2).



Building and testing the modules in the suppliers’ workshops also improves product quality. The modular construction principle also reduces the costs of maintaining and modernizing the ships. Mission modularity can be best illustrated by the Danish STANFLEX-concept (see Figures 6.1-3 and 6.1-4). This design originally replaced three classes of ships (6 Fast Attack Craft, 8 Patrol Craft, and 8 Mine Countermeasure Vessels) with one Standard Flex 300 design using a standard 54-meter GRP hull with four standardized container positions.

P550P550P550

Figure 6.1-3. STANFLEX Concept



Figure 6.1-4. Role Flexibility of STANDARD FLEX 300

In 2003, there were 12 different types of FLEX containers (dimensions 3.5 x 3.0 x 2.5 meter), which could be employed to change the ship’s weaponry and equipment in support of varying missions. This flexibility makes it possible to use the same platform for many roles, as indicated by Figure 6.1-4. The STANFLEX-concept inspired the U.S. Navy to apply mission modularity to their new Littoral Combat Ship (LCS) Program. The LCS will have so-called Focused Mission Capabilities in support of effective operations in the littorals. These focused, or modular, capabilities concern Mine Warfare (MW), Anti Surface Warfare (ASuW) and Littoral Anti-Submarine Warfare (ASW). 6.1.4 Design Characteristics To apply mission modularity the ship must be configured with core systems that are resident in the ship in all configurations, with the purpose of carrying out all core ship functions such as navigation, C4I, or other capabilities common to all missions. In addition, modules are to be defined that will enable the ship to perform all core ship functions and at least one modular mission or inherent capability. For example, it is possible to use mission modularity to cover all missions to be carried out by either a multi-mission frigate or an OPV by using one core ship as a Seaframe for modular reconfiguration. As previously described in section 3.1, this effect has been visualized in Figure 6.1-5. This figure shows that, using a modular concept, one Seaframe can replace both a multi-mission frigate and an OPV as it can be adapted to have both their capabilities. For quick reconfiguration of the ship the modules should be identical with respect to size and the ship’s interfaces. An important aspect of the success of applying mission modularity is the design of the C4I system used as the backbone of the Seaframe. Both the hardware and software architecture of this system must be very open and flexible.



Functional spectrum

Incr

easi

ng v

iole

nce

OPV

Military Power

Military Control

Military Patrol

Military Aid

Multi MissionFrigate

CorvetteCore

Seaframe

MissionModule 1

MissionModule 2

MissionModule 4

MissionModule 3

Figure 6.1-5. Tasks of Both a Multi-Mission Frigate and an OPV Executed by a Corvette Using Mission Modularity

A uniform way of accessing data and services is required independently of the choice of supplier. Automatic recognition and testing of new hardware is needed for the quick change of modules. As such, the use of multi-function consoles is an advantage, avoiding expensive and time-consuming hardware changes in command and control rooms. For a successful application of mission modularity, the development of an industrial standard becomes a must. Present WINDOWS or LINUX environments can provide these capabilities and, therefore, it is likely that C4I systems will be based on the same or similar technologies. 6.1.5 Advantages and Disadvantages The main advantages of mission modularity are:

• Same result, or better, achieved with fewer and/or smaller ships, • Platform and equipment de-coupling, • Increased redundancy, • Easy maintenance/overhaul/repair, • Easy upgrading/re-equipping, and • Easier to build the next generation.

The main reason for applying mission modularity is to reduce total ownership cost (TOC). When a ship can be reconfigured for each individual mission, the initial ship can be smaller as less equipment is needed onboard at the same time. The crew size can be tailored to each mission, resulting in fewer personnel onboard. Also the total number of Seaframes needed can be reduced; the 14 ships of the Danish Standard FLEX 300 design replace three specialized classes and a total of 22 ships. Finally, a higher level of standardization within the fleet results in cost reductions. This flexibility of mission modularity also facilitates the separate production and platform integration of modular systems as well as maximizing the life-cycle flexibility for use of future systems upgrades. The use of standard weapon and system modules also supports logistics. When the same standard modules are widely used within the fleet, it is easy to use these modules in a maintenance concept based on repair by replacement. The use of an open-architecture computing environment makes it possible to refresh



technology and upgrade software much cheaper and faster, and, therefore, could make the development of a next generation of ships much easier. An operational advantage of mission modularity is the redundancy in the number of ships which are available for specific missions. However, there is also an operational drawback; unlike a multi-mission frigate, a reconfigurable Seaframe does not deploy with all capabilities simultaneously. This lack of instantaneous flexibility can become a problem during the execution of a specific mission when unexpected capabilities are required, forcing the ship to leave the theatre. This could result in the need for forward logistic support centers to reconfigure ships in the vicinity of the area of operations. To reduce this lack of instantaneous flexibility, planning becomes an important issue when mission modularity is applied. The accurate information on availability and status (configuration and readiness) of all Seaframes, equipment modules, and manning detachments becomes an important input for the planning process needed to make mission modularity a success. Mission modularity has other consequences which must be addressed. Storage facilities are needed for extra modules. Some weapon or sensor modules likely need special storage spaces with special environmental control. Extra testing facilities may be required to ensure that new modules are properly installed and function correctly. When modular teams are used, those teams not being used should be tasked other jobs when not onboard. In general, the introduction of a modular concept involves extra, and more careful, planning to ensure that the ships are reconfigured in a timely manner with the right modules and a crew that is educated and trained to do the job. 6.1.6 When is Mission Modularity an Option? Before opting for mission modularity, a mission analysis must be performed. The types of operations, as listed in section 3.0, provide an important key to identifying the essential tasks, functions and capabilities of the ship to be designed. The analysis process starts with defining the different missions. These missions are executed using a subset (usually standard) of naval operations, which, in turn, consist of a specific number of tasks to be performed. As each operation consists of a set of tasks to be executed simultaneously or in succession, and since every task comprises a set of functions, the “tree”, as visualized by Figure 6.1-6, can grow very fast.

TASK

OPERATION

TASK

FUNCTION

CAPABILITY

FUNCTION

CAPABILITY

CAPABILITY

MISSION

OPERATION

MISSION MISSION

Figure 6.1-6. Mission Requirements Breakdown Structure



This breakdown of missions into capabilities, therefore, can be a tedious and a time-consuming exercise. However, by using existing solutions or systems, the analysis process can be shortened, simplified or focused on only the relevant capabilities. Within a naval environment, the following set of performance categories, including their next-level functions, can be distinguished (see also Figure 6.1-7):

• Operate: mission support (C4I, sensors, weapons, vehicles, etc.), mobility • Sustain: readiness (training, maintenance), endurance and range, human support (hotel) • Survive: susceptibility (signatures), vulnerability, recoverability

TASK

OPERATION

MISSION/SCENARIO

OPERATION OPERATION

TASKTASKTASK

FUNCTION

CAPABILITY

FUNCTION FUNCTION FUNCTION FUNCTION

CAPABILITY

CAPABILITY

CAPABILITY

CAPABILITY

CAPABILITY

OPERATE

SUSTAIN

SURVIVE

effectiveness

Figure 6.1-7. Relationship between Generic Functions versus Tasks

However, other category breakdowns are possible as long as all functions are covered. In generic terms, as indicated in Figure 6.1-8, the options for applying mission modularity in a SLC or OPV are limited to the modularization of payload-related equipment and personnel. When sustainability is a variable (i.e. 5 days Military Patrol versus 30 days Military Control), one additional option is to use modules as shops and storerooms in order to extend the ship’s sustainability. With respect to survivability, taking into account the cost-effectiveness of technological options available to date, the most likely option for modularization is function-related equipment and personnel on NBCD. For missions executed in a low-threat environment, a reduced vulnerability and recoverability level might be an option to reduce mission in-service costs.



OPERATE

SUSTAIN

SURVIVE

MISSION SUPPORT

MOBILITY

READINESS

HOTEL

SUSCEPTIBILITY

VULNERABILITY

ENDURANCE

++++ SEWACO, equipment, cargo, personnel

o

+ spares, personnel

+ capacities, personnel

+ consumables, personnel

o

+ armour - protection/ NBC - equipment, personnel

+ Damage Control – equipment, spares, personnel

Functions; support/ applicability mission modularity provide:

RECOVERABILITY

Figure 6.1-8. Ship Functions versus Applicable Mission Modularity

As Mission Support is the most promising function for applying mission modularity, this function has been subdivided further. In general, these sub-functions are very similar for military operations and, therefore, the following standard breakdown can be used as a blueprint:

• Information Gathering (Intel) • Search • Detect/Locate • Classify/Identify • Decide • Engage • Assess

It is obvious that for the execution of most of these functions, the use of the correct sensor and C4I suite becomes an essential part of the required solution. The actual engagement can be both offensive and defensive, and refers to the need for weapons, boarding teams, rescue equipment, etc. By defining the required function-related capabilities for each task, it is possible to compose matrices for each operation (see Figure 6.1-9). A comparison of the commonality between these matrices indicates the required core capability of the ship. The differences in capabilities, therefore, may be considered further as candidates for modularization. A simple method for defining the breakdown of operations at task-level, while still providing sufficient detail to support the specification process for OPVs and SLCs, can be achieved by relating the tasks to the specific situation, event or threat the operation is aiming to counteract in a proactive or reactive manner. In this way, the tasks to be executed to support all operations within the four clusters of operations, as defined in section 3.0, are very similar. Figure 6.1-10 illustrates the generic tasks of the defined clusters: Military Aid, Military Patrol, Military Control and Military Power.



OPERATIONAL TASKS: task1 task2 task3 task4 task5

FUNCTION:

function 1

function 2

function 3

function 5

function 6

function 7

Cap(1,1)

Cap(7,1)

Cap(1,5)

Cap(7,5)

Figure 6.1-9. Capabilities Matrix – Tasks versus Functions

AAW ASW Terrorists/ Pirates

Traffic Ships/ Objects

Cargo/ Payload

Marine Environment

Military (Sea Control)

Military (Benign)

Military (Constabulary)

Evacuate Rescue Fight/ Control Support

ASuW MW

AAW ASW ISR Military (Power projection) ASuW NSFS

Figure 6.1-10. Generic Tasks Related to the Four Clusters of SSD Operations Finally, the capabilities for eac h task can be defined as being the requirements to accomplish each generic function, as explained before. In terms of both personnel and systems, these capabilities should be derived from all information on the type of solution required. Using the generic breakdown of functions, a matrix can be developed to define capabilities for each combination of specific tasks and functions. This has been visualized in Figure 6.1-11.



MILITARY AID: Support Rescue Evacuate Fight Control

FUNCTION:

Info gathering

Search

Detect / Locate

Classify / Identify

Decide

Engage

Assess

capabilities

TASKS MILITARY CONTROL: Terrorists/Pirates AAW ASW ASuW MIW

FUNCTION:

Info gathering

Search

Detect / Locate

Classify / Identify

Decide

Engage

Assess

capabilities

MILITARY PATROL: traffic ships cargo marine environment

FUNCTION:

Info gathering

Search

Detect / Locate

Classify / Identify

Decide

Engage

Assess

capabilities

TASKS MILITARY POWER: ISR AAW ASW ASuW NSFS FUNCTION:

Info gathering Search

Detect / Locate Classify / Identify

Decide Engage Assess

capabilities

Figure 6.1-11. Capabilities Matrices

In certain situations, it could be necessary to use next-level tasks and functions to identify new candidates for modularization. However, tasks and functions at the highest level should be used to identify the largest modules. This exercise should be done for each scenario to decide if modularity is still an option according to whether different operations are performed simultaneously or consecutively. This method also indicates the minimum capabilities required for the Seaframe. 6.1.7 Seaframe versus Candidates for Modularization Referring to the required Seaframe, it is likely that a core suite for mission support, based on a common C4I, can be defined, as most operations require the same functions in similar environments. However, as the environment for ASW differs very much from other operations, it is expected that ASW sensors can be modular (see Figure 6.1-12).

Figure 6.1-12. ASW FLEX-Container Onboard Danish STANFLEX



As certain operations require more accurate sensors for information gathering, search, detection and identification, the possibility and operational advantages of using unmanned remote vehicles as modules for this purpose becomes an obvious solution. Other promising candidates for modularization are equipment in support of engagement. These consist of weapon systems and other equipment related to Military Patrol and Military Aid, such as manned off-board interception and rescue vehicles (small craft, helicopters) and equipment to assist humanitarian operations. The use of generic off-board vehicle locations, or zones, onboard the Seaframe could provide a very flexible solution. For off-board underwater vehicles or retractable modular sensors, the incorporation of a moon pool in the Seaframe could be an option. As indicated by Figure 6.1-8, the functions related to mobility and susceptibility (i.e. signatures) are unlikely candidates for modularization. The same applies to space requirements related to the Sustain function and the design measures supporting vulnerability. However, the required capabilities related to these functions are important as they strongly influence the design and, therefore, the costs of the Seaframe. This means that the required capabilities related to speed, endurance, signatures and vulnerability need special attention. 6.1.8 Cascaded Modularity When mission modularity is used to the extreme, a cascaded concept can be formed. Seaframes can become modules within a group of ships operating in pairs or triplets, pooling their resources for mutual support and for optimal tactical advantage and sustainment. Also, the modules of a Seaframe can, themselves, be based on reconfigurable frames or carriers. The flexibility of such a concept is very well expressed by the success of the Mk41 launcher. Also, the possibility of applying modularity to the design of off-board vehicles is likely to become a trend. Although overt and clandestine detection, mapping and neutralization use different equipment, the autonomous and remote-controlled carrier could still be the same. 6.1.9 Mission Modularity: Old Solution With New Perspectives Mission modularity is more likely to be a success when this solution is applied at fleet level or to a relatively large class of ships. The uncertainty and the risks involved in expeditionary peace support operations require a certain level of flexibility, affecting the minimum number of necessary capabilities of the core ship or Seaframe. The need for more ships, with different modular configurations assigned to specific tasks in support of the mission, is likely to remain unchanged. From that point of view, the benefits of a fleet concept based on Seaframes and mission modules are mainly related to the cost and redundancy benefits as a result of standardization. The present development in UAVs, USVs and UUVs, however, will further stimulate the trend for standard Seaframes . Such ships can be used in a very cost-effective way to do most of the tasks related to UN-supported peace support missions since they are mainly operating in a low or medium-threat environment. Also, for the initial phase of a littoral mission, mainly focused on situational awareness and development of access and non-combat related tasks, a SLC using mission modularity could serve as a cost-effective and complementary solution to existing fleet concepts. Therefore, for the majority of smaller ships, dedicated and specialized to specific tasks (MCM, Intel, Hydrographical research etc.) in support of the sea patrol and sea control in a low and medium-threat environment, their replacement by a class of standard Seaframes could be a likely option. The application of mission modularity is not a new concept. The best theoretical example is probably the highly successful aircraft carrier, as its weapons system, the aircraft, is inherently highly modular. Similarly, it appears as if mission modularity has been reinvented for small ship design. However, the



original meaning of a Platform as a weapon-carrier has long been recognized and re-applied by the designer in accordance with the original meaning. In short, the solution was always there. 6.2 Alternative and Advanced Hull Forms 6.2.1 Introduction Allied Naval Engineering Publication 52 on Advanced Naval Vehicles was published in the mid 1990s to summarize the work of NATO group SWG/6. The vessel types covered in the ANEP were:

• Air Cushion Vehicles (ACV) • Surface Effect Ships (SES) • Small Waterplane Area Twin Hull (SWATH) • Catamaran • Trimaran • Hydrofoil

ANEP 52 used the monohull as a reference hull form for comparison. This paper includes a brief section on monohulls. The aim of this section is to provide a stand-alone supplement to ANEP 52. It will summarize developments in advanced hull forms since the original publication of ANEP 52 in 1997 up to 2003. However, the majority of ANEP 52 is still valid. Advanced fast monohulls of displacement, semi-displacement and planing type are compared against other types of modern vehicles. In addition the Deep-Vee hull form is compared against the other competitive type of monohulls, the round bilge hull form. All comparisons refer to similar-sized ships and they are based on the following characteristics (Repetto, 2001): • Platform stability, deck area, volume space and draft weight and trim sensitivity. • Range of speed and propulsion configuration • Seakeeping and maneuvering characteristics • Global and local strength, slamming loads • Survivability (stealth characteristics and vulnerability) • Acquisition and operating costs. Modern vehicles are classified into three major categories according to the way their weight is supported, i.e. hydrostatic buoyancy, hydrodynamic lift and powered lift. These categories form the corners of the classical sustention triangle, while along the sides and inside the triangle hybrid hull forms can be found. Thus, advanced monohulls (semi-displacement and planing) are located along the side connecting hydrostatic buoyancy with hydrodynamic lift.



Hydrostatic Buoyancy (displacement hull)

Hydrodynamic Lift

Powered Lift

Figure 1. Classical sustention triangle Figure 6.2-1 Classical sustention triangle.

On the basis of the above classification of ship types advanced monohulls are first compared with displacement ships encompassing SWATH, conventional displacement catamarans and trimarans. SWATHs, which have a maximum speed not exceed 25 knots, are superior with respect to seakeeping and offer a large deck for helicopter operations. However, due to their increased wetted surface, they higher installed power requirements, and their draft (which is large anyway) and trim are sensitive to displacement changes. Their acquisition and operating cost is higher than that of monohulls. In order to increase the attainable speed of SWATHs, the stern is modified to that of a planing catamaran. Displacement catamarans operate at higher speeds at the same cost, offer larger deck area, reduced roll motions, higher initial stability, better maneuverability and survivability. However, they suffer from structural problems in the transversal box connection and have higher vertical responses. Displacement trimarans, on the other hand are expected to further increase the advantages of catamarans, while they eliminate their disadvantages.

At the hydrodynamic corner of the sustention triangle the hydrofoils are located. Both types of hydrofoils surface piercing and the fully submerged achieve higher cruising speeds, higher levels of comfort up to the wave heights, which prevent foil borne mode, and excellent maneuverability. However, even in the hull borne mode of operation in very rough seas, foils reduce both vertical and lateral motions. On the other hand, their principal disadvantage is their limited payload capability and their large draft. At the power lift corner of the sustention triangle Air Cushion Vehicles (ACV) are located. Among the pros of these vehicles are the ability to operate at very high speed, their low vulnerability to underwater explosions, their small draft and underwater signatures and their amphibious operation. However, they are affected by winds, they are sensitive to trim and have high acquisition and maintenance costs due to seals and lift fan systems and specific electronic equipment for ride-control devices.

The same corner of the triangle can also be allocated to Wing in Ground (WIG) vehicles, which can be seen as a crossover between an ACV and an aircraft. These vehicles, which operate at speeds in the range of 50 to 250 knots, have a very high transport efficiency expressed as the amount of fuel used per passenger per knot. However, only a sufficiently large WIG, weighting around 5000 t would fulfill all expectations concerning efficiency and seaworthiness, while a power several times that required for cruising is necessary for taking-off the craft.

A popular type of hybrid hull form is the Surface Effect Ship (SES), a crossover between a displacement catamaran and an ACV, which operates at speeds in excess of 40 knots, with reduced underwater signature levels and improved shock resistance to underwater explosions, good platform stability, shallow



draft and large deck area. It also has better calm water transport efficiency ET for volumetric Froude

numbers 3

12n

))(s/m[g

]s/m[VF∇

=∇ higher than 2 (Blount, 1993)

The calm water transport efficiency ET is defined as:

[ ] [ ][ ] 102.0 KWP

s/mV mtE T

∆=

In the above relations: ? = the weight of the vessel, ∇ = the volume of displacement that corresponds to the weight of the vessel, V = the ship speed, P = the total power used for propulsion and dynamic lift.

However, this type is not amphibious and suffers from significant speed loss in head seas, higher production and maintenance costs.

Wave piercers form another type of unconventional hull form. They encompass displacement and hybrid monohulls, as well as hybrid catamarans. The fitting of a tumblehome bow offers improved calm water resistance characteristics both at intermediate (displacement mode) and high (planning) speeds, reduced structure loading due to impact loads (slamming) and low Radar Cross Section (RCS) signature. Proceeding now to the comparison of the two major monohull competitors, deep-Vee hull form possesses better seakeeping qualities resulting in reduced power requirements in confused seas, better maneuvering, dynamic stability and course-keeping characteristics. Its calm water performance is, in general, inferior to that of an equivalent round bilge hull at the lower speed range (up to a Froude number of 0.60-0.70), while it becomes superior at higher speeds (Blount, 1995). Finally, deep-Vee hull provides more internal space than the round bilge one and it can easily be fitted with water jets for operation in shallow waters. 6.2.2 Monohull 6.2.2.1 Description of Hull Type For most applications, a monohull can provide a suitable solution to an operational requirement because of the inherent flexibility of this hull type. These hull forms can broadly be broken down into three types:

• Displacement (Froude Number up to 0.5) • Semi-displacement (Froude Number 0.5 to 0.9) • Planing (Froude Number above 1.0)

Hull type selection is dictated by the intended service. Typical small ship applications would be as follows: Displacement Hulls Displacement type hull forms are used for larger SLCs, OPVs and MCM ships. Semi-displacement Hulls Semi-displacement hulls are used for fast attack craft and corvettes. Appendix 9.8 provides a selective summary of semi-displacement hull form powering performance.



Planing Hulls Planing hulls are used for high-speed fast patrol boats. As compared to the conventional displacement type hull forms and the semi-displacement monohull hull forms discussed in Appendix 9.8, deep Vee hull forms and anti-slam bow bulbs have matured as options for displacement and semi-displacement hulls. The deep Vee hull form is now widely used in high-speed monohull ferries, as well as by recent OPVs and SLCs. The deep Vee hull form reportedly results in relatively low pitch, heave and yaw motions, and is reported to provide exceptional roll damping. When operating in head seas added drag is significantly reduced relative to conventional displacement or semi-displacement hull forms. Use of anti-slam bow bulbs significantly reduces the probability of slamming. Therefore small SLCs or OPVs with deep Vee hulls and anti-slam bows should be able to use full power in higher sea states than conventional hull forms. However, the use of an anti-slam bow will increase the navigational draft of the hull. SLCs and OPVs generally operate at varying maximum speeds. These designs may also need to operate across a broad spectrum of speeds, from loiter to flank, and to meet very specific task driven seakeeping and maneuvering requirements. Consequently, the selection of the optimum hull form or hull type should be based on the results of whole ship trade off studies which fully address the impact on ship size, cost and all performance requirements. Because SLCs and OPVs can require operation across a broad spectrum of speeds and loading conditions, and may have unique performance requirements such as low navigational draft, limited length, or limited freeboard, these trade-off studies will necessarily be complex and multi-dimensional. It should also be noted that ride control systems are now available which can be used to reduce roll and pitch motions. These systems are particularly applicable to the small ships being discussed herein. 6.2.3 Air Cushion Vehicles 6.2.3.1 Description of Hull Type Air Cushion Vehicles (ACVs) are characterized by being entirely supported by a cushion of pressurized air, normally retained within a flexible skirt system. The purpose of the cushion of air is to minimize the resistance to motion and to soften the suspension system for operation over waves or rough terrain. The skirt design may permit the cushion depth to be increased, but it always has to be able to provide adequate stability. Cushion pressures are comparatively low (typically less than one-tenth of an atmosphere, i.e. below 10 kPa or 1.5 psi). Because of this low-pressure footprint, ACVs can operate over many surfaces and can, therefore, be regarded as being amphibious. The outstanding features of ACVs are summarized below:

• High Speed An ability to operate at very high speeds due to their low resistance, both over water and on land.

• Low Vulnerability The air cushion provides the craft with a low vulnerability to damage from to mines underwater explosions.

• Low Draft Minimal draft and the lack of surface contact with the hard structure minimizes underwater signatures.

The primary limitation of ACVs is very limited endurance at low speeds, which is related to the fact that the same power is required to maintain the ship on cushion at low speed as at high speed. The missions, which ACVs can perform, are therefore generally limited. ACVs are generally only applicable to missions requiring relatively short-range operations. Hence the ACV has primarily been used in niche roles where its shallow draft and/or amphibious capability provides unique advantages.



Military ACV applications include amphibious assault, logistic support and mine countermeasure (MCM) roles, as well as coast guard and policing duties. 6.2.3.2 Significant ACVs Built Since 1995 Greece has acquired four Russian POMORNIK (ZUBR) class ACVs (two from Russia and two from Ukraine). This amphibious assault ship was originally developed in the 1980s. It has a capacity of 130t on the RO-RO deck and a full-load displacement of about 550t. The Finnish Navy has undertaken the development of a prototype Combat Craft Air Cushion Vehicle for use in Finnish Archipelago. The craft is 28m long with a 16m beam and displaces about 90t. Several missions have been considered ranging from tactical mine laying to a surface missile strike. This ACV includes several novel design features, such as an advanced skirt design and the low-profile bow thrusters. The hull is constructed of aluminum and the deckhouse is constructed of composite sandwich panels. Power is delivered by two gas turbines of the same type, as used in the U.S. Navy’s LCAC. The U.S. Navy LCAC (Landing Craft Air Cushion)/MCAC series of over 90 vessels is undergoing a service life extension program. Most of the new ACVs are quite small and are intended for coast guard use or for amphibious forces. Since the mid-90s, over 35 ACVs of this category have been built or are on order. Their full-load displacement varies between 5.5t and 70t. Most are of British design. Types include an enlarged version of the AP1-88 by GKN Westland, built under license in Canada for the Canadian Coast Guard. The 69t DASH 400-series is used for flood control and icebreaking in St Lawrence Bay. Four 6.8t GRIFFON 2000 TDX have been built for UK Armed Forces Royal Marines; one for the Estonian Coast Guard and three for the Finnish Coast Guard. The latest orders include a new larger 21m by 11m GRIFFON 8000 TD (M)-type; six for the Indian Coast Guard and five for the Saudi-Arabian Border Guard where sixteen SRN6 hovercrafts have been used for 30 years in military/paramilitary operations. Other types include the British ABS M10-type; one for Sri Lanka Patrol Forces and four for the Swedish Coast Guard. Also, four British SLINGSBY SAM 2200-type were acquired for the Finnish Frontier Guard between 1993 and 1999 as well as three more of this type in 1990 for Saudi Arabia. In Russia, the Almaz design, 8.6t CZILIM (TYPE 2091), has been developed for Border Guard use. The Coast Guard ACVs are generally based on commercial off-the-shelf designs. Generally, the hull is constructed from welded marine aluminum, taking advantage of simple box construction, and make use of prefabricated extruded panels. A GRP hull and superstructure has been used as, for example, in the M10 series. Table 6.2-1 provides a list of ACV ships built since 1995.



Table 6.2-1

List of ACVs Built Since 1995

Year built Country Type Number Displacement L x B Main Machinery Speed

1998 CANADA Coast Guard

AP1-188/400 2 69 t 28.5x12 m 2,66 Mw 4 diesel eng.

50 kt

1999 ESTONIA GRIFFON 2000TDX Mk2

1 6.8 t 11x4.6 m 293 kw 1 diesel eng.

33 kt

2002 FINLAND Navy

Combat Craft Air Cushion

1 prototype 90 t 27.4x15.4 m 6 Mw 2 gas turbines

50 kt

1993-1999 Frontier Guard SLINGSBY SAM 2200

4 5.5 t 10.6x4.2 m 224 kw 1 diesel eng.

40 kt

1994-1995 Frontier Guard GRIFFON 2000 TDX(M)

3 6.8 t 11x4.6 m 239 kw 1 diesel eng.

33 kt

2001 GREECE Navy

POMORNIK ( ZUBR )

4 550 t 57.6x25.6 m 43,5 Mw 5 gas turbines

60 kt

Ordered 2003 INDIA Coast Guard

GRIFFON 8000TD(M)

6 - 21.2x11 m 1200 kw 2 diesel eng.

50 kt

Ordered 2003 SAUDI ARABIA Boarder Guard

GRIFFON 8000TD(M)

5 - 21.2x11 m 1200 kw 2 diesel eng.

50 kt

1999 RUSSIA Boarder Guard

CZILIM (TYPE 20910)

4 8.6 t 12x5.8 m 320 kw 2 diesel eng.

33 kt

1998 SRI LANKA Patrol Forces

ABS M10 (UCAC) Utility Craft Air Cushion

1 18 t 20.6x8.8 m 772 kw 2 diesel eng.

40 kt



Year built Country Type Number Displacement L x B Main Machinery Speed

1999 SWEDEN Coast Guard

ABS M10 1+3 26 t 18.8x8.8 m 900 kw 2 diesel eng.

40 kt

mid 1990s THAILAND GRIFFON 1000TD

3 - 8.4x3.8 m 140 kw 1 diesel eng.

33 kt

1993 UNITED KINGDOM Royal Mariners

GRIFFON 2000TDX(M)

4 6.8 t 11x4.6 m 239 kw 1 diesel eng.

33 kt

1989-98 Life extension Program started Two sold to Japan

USA Navy

LCAC/MCAC (Landing Craft Air Cushion )

91 170-182 t 26.8x14.3 t 12 Mw 4 gas turbines

50 kt



6.2.3.3 Technological Developments in ACV Design The Finnish Navy Combat ACV includes some novel features:

• The skirt system is a new configuration with a bag and finger skirt with one transverse stability seal. The side seal employs a back-to-back finger arrangement (Figure 6.2-1). The side seal is designed as two standard open fingers that are placed back-to-back to form a type of pericell with considerable overlap of the finger tail and finger flap. With this concept, hoop tensions cannot be sustained all the way around the hemline of the cells, thus essentially eliminating the over-water drag due to scooping and snagging when operating over ice, as with a normal pericell that has a continuous hemline. This side seal configuration has been shown to have lower drag, superior roll static stability, and have the added benefit of reduced life-cycle cost.

• To reduce the height of the nozzles, a special low-profile design has been developed. The new

type of nozzle comprises a series, or cascade, of small two-dimensional nozzles (Figure 6.2-2).

Figure 6.2-2, Section Through Side Seal Assembly



Figure 6.2-3. Low-Profile Bow Thruster Nozzle

6.2.4 Catamaran 6.2.4.1 Description of Hull Type A catamaran is a ship with the hull composed of two different bodies, usually called demi-hulls, connected by an above-water cross-deck. Each demi-hull can be either symmetric or asymmetric, but the entire hull is symmetric about the ship’s centerline, i.e. each demi-hull is the mirror image of the other. The transverse distance between the two demi-hulls at the waterplane is called the gap (Figure 6.2-3). The space located between the two demi-hulls and under the cross-deck is called the wet tunnel. SWATH and SES can be considered special types of catamarans, but, due to their special features, they are usually considered as different types of unconventional craft and will be separately discussed. Catamarans can be placed in two different classes:

1) Conventional displacement catamarans Displacement catamarans have been constructed for the following roles:

• Oceanographic ships • Hydrographic ships • Submarine rescue ships • Mine countermeasure ships • Environmental protection ships for oil spill recovery



Catamarans provide substantially more main deck area per displaced tonne than displacement monohulls. However, they have relatively greater wetted surface, and hence greater drag at low Froude numbers. Seakeeping depends on the wet tunnel height. Ride control systems have been developed, but these generally have limited effectiveness at low speed. Because of their shorter roll periods and propensity to pitch at low speeds, the usefulness of the additional deck area generated by catamarans is often constrained by unacceptable seakeeping performance at the deck boundaries, particularly at low speeds. Therefore the number of successful conventional displacement catamarans has been limited.

2) Fast catamarans

Usually operating at semi-displacement speeds some fast catamarans have employed wave-piercing hull forms. Fast catamarans have been considered and constructed for the following roles:

• Law enforcement • Fast ferries/transports • Special operations

High-speed aluminum ferry catamarans have been very effectively employed in relatively calm waters. Pitch in moderate seas has been minimized by ride control systems. However these ferries have proven to have relatively poor open ocean seakeeping in beam seas, because of their short roll period, or when operating at high sea states when slamming severely constrains operability. Wet tunnel height has also been relatively limited.

Figure 6.2-4. Catamaran Hull Configuration 6.2.4.2 Significant Catamarans Built Since 1995 Numerous high sped catamarans ferries have recently entered service. The Australian Navy leased a commercial ferry from INCAT in 2000-2001. The ship, named the HMAS Jarvis Bay, was used to move



supplies and relocate refugees from East Timor with very little modification from its commercial variant. The vessel is typical of INCAT’s Wave Piercing technology seen around the world in the fast ferry market. The U.S. Navy is currently leasing a 313-foot Wave Piercing Catamaran from INCAT, designated HSV-X1. Possible uses for this ship include insertion and extraction of special operations troops, mine warfare, anti-submarine warfare, surface warfare, maritime reconnaissance, command and control, humanitarian assistance and evacuation, force protection and re-supply at sea. The craft has been fairly heavily modified to suit the mission requirements, including passenger compartments and a helicopter deck. Additionally, the Navy is pursuing a second lease of another INCAT catamaran that will be heavily used by the Mine Warfare Command and Marine Corps. The U.S. Navy and Marine Corps will be using this craft in experimental roles to support such operational concepts as Sea Basing. The U.S. Marine Corps has also leased a 101m Austal Catamaran, which is being used in Okinawa to ferry troops to and from training areas on different islands within the theater. The U.S. Army is also exploring catamaran technology as a viable option for their future TSV program, which will provide the Army with intra-theater sealift. 6.2.4.3 Technological Developments in Catamaran Design 6.2.4.3.1 Hydrofoil-Assisted Catamarans (HYSUCAT) One area of technology development is with Hydrofoil-Assisted Catamarans or HYSUCAT. The HYSUCAT is a hybrid of a catamaran hull, fitted with a hydrofoil system, which carries part of the craft's weight at speed, resulting in an economical high-speed craft. This is accomplished through dynamic lift, which reduces the wetted area of a catamaran in water. There has been a lot of research and numerous papers written on this subject, so much so that it has become its own hull form category. 6.2.5 Surface Effect Ships 6.2.5.1 Description of Hull Type Surface Effect Ships (or SES) have a twin-hulled catamaran-type form, but are primarily supported on an air cushion generated by lift fans. The cushion is retained between the rigid side hulls and fore and aft flexible seals. The SES can use either conventional propellers or waterjets for propulsion. The outstanding features of SES hulls are summarized below:

• An ability to operate at high relatively speeds due to their low resistance. • A shallow draft compared to displacement hulls. • Somewhat reduced underwater signature levels. • Somewhat improved shock hardness to underwater explosions.

SES hulls have been considered for fast combatant and anti-submarine warfare (ASW) roles. They also have particular application for mine countermeasures (MCM) due to their low signatures and reduced vulnerability. A series of such craft is now in production. The trend in SES design has been to extend its capabilities. The main characteristics remain unchanged, but size and speed have been increasing, as well as limiting operational sea states. The main drawback for warship design is the large profile that stems from the catamaran/SES configuration because of the need for a certain height under the main body of the ship, driving volume upwards in the ship, resulting in a large visual signature. The SES design concept provides speed potentials in excess of 60 knots. The concept size limit may, with careful extrapolation from operational experience, be extended from the current limit up to displacements of 2000 to 3000 tonnes.



In addition to the high-speed capabilities of SES designs, the capabilities of the SES in specialist roles may also be significant. One such role is as a mine countermeasure vessel (MCMV), where an SES design has the following advantages:

• High speed. • Excellent seakeeping abilities • Shallow draft. • Large work deck. • Inherently low signatures. • Inherently low shock response. • Extensive use of COTS because of low signatures and shock response.

The twin hulls also enhance redundancy and survivability. 6.2.5.2 Significant SESs, Built Since 1995 6.2.5.2.1 Norwegian MCM and HNoMS Skjold The RNoN has acquired substantial experience with naval SES since the introduction of the MCMVs in 1992. The unique qualities of the SES concept, as verified by HNoMS Skjold and the Oksøy class MCMVs, are:

• Excellent seakeeping capabilities for a small ship. • Improved maneuvering capability due to waterjet separation. • Large deck space. • Low high-speed resistance.

New technologies used in Skjold are:

• The waterjet intakes are placed below the hull and are located on flat bottom panels. This has decreased the resistance, minimized problems associated with air ingestion, and has enhanced high-speed, high sea state operations.

• The L/B ratio is quite low. For speed, a high aspect ratio will be beneficial; however, this is in calm water. To improve both seakeeping and speed in sea state 3, a lower L/B ratio was chosen.

• The fan capacity is more than double of what is needed. This was done both for redundancy reasons and the ability to maintain the air pressure in higher sea states.

Rather extensive signature reduction measures have been taken for Skjold. The work deck is covered both at the bow and stern. The Main Deck is not used in normal operations. All exterior panels are either radar absorbing or reflecting. These qualities are integrated in the load-bearing structure and have had little weight impact. The panels are also laid out as large and flat, with no 90-degree corners. All hatches are flush with surrounding panels, and the deck hardware is covered or removable. The window screens are radar reflective. Air intakes to gas turbines and lift fans are covered with radar absorbing mesh. The hatches are developed by UMOE Mandal and, in addition to the above, they are Watertight, Gas-tight, EMI-Shielded, easy to operate and maintain, and low weight. All exhausts end inside the cushion or at the stern, maintaining low IR signatures in all directions except from aft. Small diesels can maneuver the Skjold at low speeds, giving the ship a low-speed/low-IR signature mode. Sandwich material has good insulative capabilities and contributes to a low IR signature. The use of a camouflage painting pattern enables the Skjold to hide among islands and even be difficult to detect visually.



6.2.5.2.2 Japan’s Primary High-Speed Vessel Program A 140m, 1000t payload, 38kt SES, is planned to enter service in 2005. TSL Kibou, a 70m, 200t payload, 50kt SES, was made as a demonstrator for this ship and has been in service as a fast ferry in Japan since 1997. 6.2.5.2.3 Textron Marine: HCAC A JJMA/UMOE Mandal approx. 75m, 1300t displacement design has been developed for the LCS competition. 6.2.5.3 Technological Developments in SES Design 6.2.5.3.1 SES Systems/Seakeeping/RCS The latest-generation SES ships have double or triple stern seals. They may also have more balanced placements of the main fan outlets to the cushion plenum than previous concepts. There has been a significant improvement in Ride-Control Systems in recent years. Skjold may be considered a fourth-generation SES design. The generations of SES designs are:

• First generation: Vosper Thornycroft SES with single-suction fans, and Hovercraft with 3D-derived skirt and bag.

• Second generation: Bell Halter SES designs, better skirt and bag designs with 2D twin-suction fans.

• Third generation: Cirrus/Br Aa SES designs, 2-loop bag, aft louvers for ride control. MCMV for RNoN, with a similar SES system as commercial SES craft.

• Fourth generation: HNoMS Skjold, 3-loop aft bag, variable geometry fan intakes, large fan capacity (100% redundancy + compensation for heavy losses in high sea states), placement of main fans is balanced with respect to the Ride-Control System, more advanced RCS (including advanced control algorithms), and the waterjet intakes are lowered.

The later-generation SES designs have vastly improved calm-water performance, with little cobblestone effect, and a very good high sea state capability. 6.2.5.3.2 Material The main construction material for SES ships is FRP, although aluminum has also been used. Recently, there has been a tendency towards more use of carbon fiber, enabling further weight reductions. This use may be cost-effective when the weight reduction can be used for optimization of the entire concept, reducing costs in most cost-groups. The lay-up of the FRP has generally moved towards the use of knitted, multi-axial fiber lay-ups and injection molding. This technique may further reduce weight by allowing reduced amounts of resin matrix to be used. Past experience has shown that the most maintenance-intensive parts of the SES are the bow seals. The main problem has been wear on the lower tips of the skirts due to abrasion and contact with the water surface at high speeds. There have also been problems with vertical tearing of the skirts, possibly because of the geometry of the skirts. The HNoMS Skjold has not experienced these problems. Additionally, the lower parts of the bow skirt are removable, greatly reducing these costs. 6.2.5.3.3 Propulsion Waterjets are most often used for propulsion; however, surface piercing and conventional propellers have also been used. Generally, this choice is driven by high-speed considerations. Particular to SES



designs, air bubbles from the plenum may occur in the boundary layer, causing propulsion problems. The experience gained from lowered waterjet intakes may also be used for other types of high-speed ships. This enables the full power to be utilized in higher sea states, and greatly reduces the undesirable engine load cycling experienced in earlier SES designs. 6.2.5.3.4 General Design Guidelines While low Froude Number monohull hull forms will experience a gradual loss of speed with increased weight, high-speed SES designs will often experience a rapid drop in speed outside the design envelope. An SES concept must be carefully designed and balanced to realize the full potential of the concept. This design should include a realistic consideration of weight growth and possible changes in operational profiles. This is perhaps the greatest challenge of designing an SES ship. Any changes outside the optimization envelope will rapidly reduce performance. The SES concept, however, is better suited to increased weight than a monohull relative to large speed loss in a low sea state. However, when encountering a higher sea state, the speed losses are mainly governed by the fan capacity and performance will depend on the margins of the fan system. There have been several cases of commercial SES craft performing well in low sea states, but far below expectations in higher sea states. The main reason for this is usually under-sized lift fans. Even though SES craft will cost more to build and, due to added complexity, more to maintain than monohulls of the same displacement. SES craft may be more cost-effective when their relative performance advantages are utilized to the fullest extent with respect to the mission profile. The comparison of cost should be performed considering either concepts with similar capabilities, or the impact of speed on overall performance. The main challenge will most often be to perform a complete system trade-off and design analysis, while utilizing state-of-the-art technologies for the different sub-systems of the craft. 6.2.5.4 Proposed Applications of SES Concrete plans for SES concepts are the previously Japanese concept and the SES competitor in the U.S. Navy’s LCS program. The trend in SES design has been to extend the proven capabilities from generation to generation. The main characteristics remain unchanged – but size and speed have been pushed upwards, as well as operational seastates. The main drawback for warship design is the large profile that stems from the catamaran/SES concepts – because of the need for a certain height under the main body of the vessel – driving volumes upwards in the ship; this may give a large visual signature. For large speed in a seaway the SES vessel is unparalleled – with speed potentials in excess of 60 knots. The vessel size may, with careful extrapolation of operational experience, be extended from the current sizes up to 2-3000 tonnes displacement. In addition to the utilization of the high-speed capabilities of the SES vessels – the capabilities in specialist roles may also be significant. One such role is as a mine countermeasure vessel (MCMV), where a SES vessel has the following advantages:

• High top speed for MCMV good coverage • Excellent sea keeping abilities, comparable to far larger monohulls • Shallow draft • Large work deck, comparable to far larger monohulls • Inherently low signatures • Inherently low shock response • Extensive use of COTS, because of low signatures and shock response • Twin hulls – enhanced redundancy and survivability



6.2.6 Small Waterplane Area Twin Hull 6.2.6.1 Description of Hull Type Small Waterplane Area Twin-Hulled (SWATH) ships have deeply-immersed catamaran-type hulls which buoyantly support the craft, but which also have greatly reduced waterplane area. The reduction in waterplane area gives SWATH designs the following outstanding features:

• Improved motion characteristics in waves compared to conventional monohulls of similar displacement.

• A small speed loss in waves. • Large deck area. • Improved propeller performance and sonar operations due to deep submergence.

SWATH designs generally have high wetted surface and relatively high drag. In order to reduce drag one design concept uses multiple underwater bodies, each supported by independent struts. The shape each body has also been optimized to reduce residual drag at high Froude numbers. This reduces the resistance at high speed. SWATH designs also tend to have relatively high structural weight. Their ability to operate at high sea states can be limited by the clearance provided below the cross deck structure. SWATHs have been built for open ocean surveillance roles where their improved seakeeping, compared to monohulls, is of importance. Smaller types of SWATHs have also been considered for coastal patrol and law enforcement duties, as well as MCM route surveillance. 6.2.6.2 Significant SWATHs Built Since 1995 There have been two significant U.S. Military ships of this type built since the publication of ANEP 52, the AGOR 26 and the T-AGOS 23. The R/V KILO MOANA, designated AGOR 26, was designed as a large general-purpose research ship. The ship, displacing over 2500 tonnes, is 182 feet long with an 88-foot beam. The AGOR 26 was built for the U.S. Navy and is operated by the University of Hawaii for general-purpose oceanographic research. The USNS Impeccable, designated T-AGOS 23, is 281 feet in length, has a beam of 95.9 feet, displaces 5,370 long tonnes, and is capable of sustaining speeds up to 12 knots. This vessel is operated by the Military Sealift Command and is used to track submarines and perform other underwater acoustic surveillance missions in support of Integrated Undersea Surveillance System (IUSS) mission requirements. The other significant SWATH built since 1997 is the world’s largest design the Radisson Diamond, built for Radisson Cruise lines. It is 131m long and displaces almost 12,000 tonnes. 6.2.7 Trimaran 6.2.7.1 Description of Hull Type Trimaran ships have a slender main hull with two smaller side hulls. The center main hull typically has a length-to-breadth ratio of between 11 and 19, while the side hulls have a L/B ratio from 15 to over 30. The hulls are connected by a box-like cross-deck structure which usually is integral with the main hull. The cross deck structure has the side hulls mounted beneath it. A length-to-overall-beam ratio of between 4.5 and 7 can be expected. The smaller hulls contribute approximately 8 percent of the total displacement of the ship, with a waterline length up to about half that of the main hull.



The long, slender main hull generates low residual resistance. The side hulls are generally positioned to reduce wave resistance interaction effects, although other considerations may prevent an optimum minimum resistance from being obtained in practice. Trimarans can be powered by either propellers or waterjets, although the slender main hull imposes constraints on propulsion machinery layout. It is possible to install machinery and propulsors in the side hulls, although this will tend to increase their size and, hence, resistance. For some applications the advantages of distributed propulsors on survivability and maneuvering may outweigh the resistance penalties. The outstanding features of the Trimaran are summarized below:

• Lower resistance The ability to operate at higher speeds for the same installed power as an equivalent monohull or, conversely, the ability to attain the required speed with a lower installed power.

• Cross-deck structure The wide cross-deck structure provides a useful large deck area allowing flexible deck layout arrangements. In addition, the extra length can allow more freedom in positioning motion-critical accommodations and equipment in more favorable positions. For example, helicopter landing areas can be moved much further forward of the transom.

• Good seakeeping in head seas The form affords a good seakeeping response in pitch. The improvement in pitch motions is due to the greater length of the trimaran over an equivalent monohull design. Roll response is affected by the beam, GM and inertia. As with monohulls and catamarans, too high a GM will produce an uncomfortable motion.

• Damaged stability The side hulls provide good damaged stability. Studies have shown

that damaged stability can be made to far exceed that expected for monohulls. Also, damage control, fire fighting, and even subsequent repair will be much simpler due to the accessibility provided by the platform cross-deck structure. The net result is a higher damage tolerance for the trimaran than for an equivalent monohull.

Research has shown that trimarans can experience catastrophic high roll responses when exposed to aft quartering seas. The heading at which this occurs tends to vary depending on the relative location of the outboard hull. The magnitude of the problem depends on the characteristics of the sea state and the size of the ship. For small ships like those considered herein this is considered to be a significant issue. Trimarans have relatively high wetted surface and hence high resistance at low speeds. They also result in a relatively high structural weight fraction. The designer must be aware that ships below a certain size may make layout arrangements difficult as the cross-deck structure could become non-usable volume. It is difficult to scale trimaran designs. Below a certain displacement the required structural weight would make it impossible to employ a cross deck structure that is one deck high. Above a certain displacement it is no longer structurally feasible to safely employ a cross deck structure that is only one deck high. Very large trimarans, like very large catamarans, are impossible because of the required depth and weight of the cross deck structure. 6.2.7.2 Significant Trimarans Built Since 1995



6.2.7.2.1 RV Triton In 1998, the UK Ministry of Defence placed a contract for the design and construction of a trimaran demonstrator, RV Triton. The primary role of Triton is to carry out trials as a trimaran technology demonstrator. The focus of these trials is to understand, as much as possible, structural responses to motions and ship handling, thus providing input into the decision-making process for a future frigate program. When these trials are complete, Triton will be used as a trials ship available for charter. 6.2.7.2.2 Principal Particulars

Triton’s principal characteristics are: Length Overall 98m Length Between Perpendiculars 90m Waterline Length 91m Beam Overall 22.5m Depth to Main Deck 9.0m Design Draft 3.2m Design Displacement 1035t Side Hull Displacement 3.7% of total D Main Hull CB 0.49 Main Hull B/T 2.14 Side Hull Waterline Length 34.2m Side Hull Waterline Beam 1.45m Side Hull Draft 2.31 Side Hull Separation 9.3m Side Hull Position 2.25m aft amidships Maximum Speed 20 knots Range 3000 miles

6.2.7.2.3 Hull Form The main hull is a round bilge form with underwater sections approaching semi-circularity amidships. A gentle rise of buttock lines aft leads to a transom with minimal immersion. The side hulls are a multi-chine design on the outboard face with a plane inboard face. This shape was selected for ease of manufacture. A parallel section extends above and below the waterline to avoid large changes in waterplane area as the draft changes. Prior to commencing construction, a full range of hydrodynamic testing was carried out in the Haslar tank facilities. 6.2.7.2.4 Structural Arrangement Load prediction was undertaken using DNV’s SWAN hydrodynamic load prediction tool. Loads assessed using this tool included: longitudinal vertical bending, longitudinal transverse bending, pitch connecting moment and transverse load. Unusual load cases analyzed were: unsupported side hull and buoyancy due to roll angle. The structural style of RV Triton was developed to be similar to that which would be used on a trimaran frigate so that trials results obtained would be representative of those for a future frigate. The use of thin plating and small closely spaced longitudinal stiffeners also produced higher strains and was, therefore, well suited for strain gauge measurement in the role of a demonstrator.



Fatigue was an important consideration and the following areas were identified as needing special treatment: deck longitudinals amidships, bottom longitudinals amidships, wet deck to center hull connection in way of bulkheads, and wet deck to side hull connection in way of bulkheads. The structure was approved by DNV using their High Speed Light Craft (HSLC) rules. Class notation included helicopter deck, container loading and unattended machinery space. 6.2.7.2.5 Layout The layout of Triton is not representative of a naval ship, but merely met the requirements of a trials vessel. Accommodation spaces were located in the superstructure and the mid length of the first deck of the main hull. The main hull aft was dedicated to electrical spaces, including the generator room and the medium and low voltage switchboard rooms. 6.2.7.2.6 Machinery Arrangement Triton is powered by an integrated full-electric propulsion system with power generation from two 2MW Paxman 12VP185-driven diesel generators. This power station supplies the main propulsion train of the ship, which consists of a 3.5MW AC electric motor turning a single shaft which drives a fixed-pitch propeller. The ship is also fitted with a Schottel right-angled thruster in each side hull. These units are driven by 350kW electric motors mounted towards the sides of the vessel on the cross-deck. 6.2.7.2.7 Stability Performance Triton complied with the SOLAS High Speed Craft Code and UK MOD NES 109 surface warship stability standard. In order to achieve compliance with damage stability criteria, a high level of subdivision was required in the side hulls. 6.2.7.2.8 Trials The structural and hydrodynamic trials program was successfully completed by UK MOD and trials data recorded on TIS. The U.S. DOD undertook the task of analyzing the trials data. The results of this analysis will be used to calibrate the computer design tools that have been developed and will be used in the evaluation stage of the next UK frigate program. 6.2.7.3 Proposed Applications of Trimaran Hull Type 6.2.7.3.1 Auto Express 126 Trimaran While not designed for military use, the Auto Express 126 trimaran is worthy of mention. Australian shipbuilder Austal Ships and European ferry operator Fred Olsen, S.A. have announced the signing of a contract for the world’s largest high-speed multihull vessel. The 126.7-meter cargo-vehicle-passenger fast ferry, with a beam of 30m, will be larger than any existing diesel-powered fast ferry (catamaran or monohull) and is believed to be the world’s largest all-aluminum ship. The planned delivery is in the second half of 2004. The design is intended to overcome some limitations in terms of capacity and passenger comfort when operating in rough seas (such as around the Canary Islands) associated with catamarans. The new design will combine good comfort, provided by the soft movement of monohulls, with the low resistance and very good stability and carrying capacity of catamarans. The superior seakeeping performance of the trimaran will provide passengers with significantly enhanced levels of comfort compared to existing fast ferries and is also expected to result in noticeably higher levels of operability.



Power will be provided by four diesel engines driving waterjets to maintain service speed in excess of 40 knots and provide the capacity to carry 1,350 passengers, over 340 cars, and a substantial number of trucks. The speed and seakeeping performance of the hull form has been verified by extensive analysis, including multiple tank testing sessions at some of the world’s leading facilities. Austal has also built and trialed an 11-meter manned technology demonstrator and has modeled the ship’s structure in detail using sophisticated finite-element techniques. The ship will be constructed in Austal’s facilities using techniques and materials that have been proven and refined over many years on high-speed ferries. 6.2.7.3.2 Trimaran Hull Form – U.S. Navy Combat Ship Project A team led by General Dynamics, including Austal Ships and Austal USA, has been awarded one of three competing contracts for the preliminary design of the United States Navy’s LCSs. The team’s proposal for the LCS is based on Austal’s 126-meter high-speed aluminum trimaran hull form. Following completion of the seven-month LCS preliminary design stage, the U.S. Navy will select two builders to build two prototype ships. One will commence construction in early 2005 and the other in early 2006. It is anticipated that, in late 2007, one team will be selected to continue with the program, commencing construction of three ships in 2008 and four in 2009. The Navy predicts that up to 60 LCSs may eventually be required. In accordance with U.S. law, all ships will be built in the United States. 6.2.8 Hydrofoils 6.2.8.1 Description of Hull Type Hydrofoils are ships that are dynamically lifted and supported on wing-like lifting surfaces. Hydrofoils experience significantly reduced ship motions, compared to conventional monohulls and require significantly less power at high speeds. Hydrofoils come in two types: surface piercing and fully submerged. Hydrofoils had wide application in the former USSR, both for civil (passenger ferry) and naval roles. Only six hydrofoils remain in the Russian Navy, with five in the Ukrainian Navy. Examples of hydrofoils in service include the following:

− patrol hydrofoil of Mukha class (1145 project): full displacement 400 tones, maximum speed 40 knots;

− missile hydrofoil of Matka class (206MP project): full displacement 260 tones, maximum speed 40 knots;

− torpedo hydrofoil of Turya class (206M project): full displacement 250 tones, maximum speed 40 knots;

− patrol hydrofoil of Muravey class (133 project): full displacement 212 tones, maximum speed 60 knots.

Hydrofoils have the following characteristics:

Aspects Assessment Speed, power and endurance

Very fast foilborne, but limited hullborne in a seaway and poor endurance due to low fuel weight

Space and layout Poor Structural design and weight Very poor



Stability Very good hullborne but foilborne degraded by wave effects in deep water

Maneuverability Good Noise, radar and magnetic signature

Good

Payload capacity Poor Construction cost and build time

Very high

Through-life costs Average 6.2.8.2 Significant Hydrofoils Built Since 1995 Construction of small submarine chaser - hydrofoil "Sokol" (modified Mukha-class, third vessel in the series) is under the way in Ukraine. These hydrofoils are intended for ASW operations in littoral waters. Main particulars:

− Length Overall, m 50 − Beam Overall, m 10 − Full Load Displacement, t about 500 − Speed, knots:

o maximum 60 o cruising 50-55 o hullborne 12

− Seaworthiness, Beaufort scale: o foilborne up to 5 o hullborne unlimited

− Range, miles: o foilborne 800 o hullborne 1200

− Crew, persons 35 − Main Power Plant: 1x10000 hp and 2x20000 hp gas turbines, 2x200 kW diesel-generators − Armament:

o 1-76 mm gun mounting o 1-30 mm gun mounting o 1 portable AAW complex o 2x4 torpedo launchers o FCS

6.2.8.3 Technical Developments in Hydrofoil Design It is assesses that hydrofoils could not find the wide application without major new qualitative improvements, due to their high costs, low serviceability, limited reliability and limited seaworthiness. 6.3 Power Systems and Propulsion Alternatives 6.3.1 Introduction Selection of the propulsion plant is a critical element in the design of a SLC or OPV. To achieve the greatest efficiency, the propulsion plant should be designed in accordance with the required operational profile. The “operational profile” provides the speeds that the ship is going to navigate or operate in, and the associated percentages of total time in operation. It also indicates the number of days the ship will spend docked or at sea, both in wartime and in peacetime.



Because SLCs and OPVs often have complex operational profiles these ships generally employ multi-shaft propulsion plants with multiple engines, often a combination of diesels and/or gas turbines (CODAD,CODAG/CODOG). Power can be combined through gears or through the water. There are significant differences between SLCs and OPVs in terms of installed power/ton of displacement, endurance and operational profile. Specialized tasks performed by small ships often have unique requirements, MCM, for example, require low magnetic signatures and precise low speed maneuvering capability. These requirements can significantly influence the choice of propulsion plant. Selection of the propulsion plant requires investigation of alternative engines, or combinations of engines, and propulsors. The choice of propulsion plant has a significant impact on the overall ship design, and should be studied on the basis of whole-ship impact trade-off studies. These studies should address machinery box characteristics, weight, KG, LCG, the overall arrangement of air intake and exhausts, appendage drag, propulsive efficiency, specific fuel consumption, and acquisition and total operating costs. 6.3.2 Types of Power Generation The most used “prime movers” are:

• Gas Turbines • High or Medium-Speed Diesel Engines • Combination Gas Turbine/ Diesel Engines

The factors that can influence the selection of the propulsion system therefore include the following:

• Cost of acquisition and operation • Overall design integration • Operational profile • Ship size and resistance • Other operational requirements such as draft or maneuvering • Maximum speed/low-speed operations • Fuel consumption • Hydroacoustic noise and other signature requirements • Weight of “plant + fuel” for specified range and operational profile • Space, arrangement and geometrical considerations • Vulnerability • Maintenance and logistic aspects • Automation • Reliability • Flexibility

6.3.2.1 Diesel Engines Diesel engine characteristics depend on engine RPM. High-speed diesels are often used on SLCs and OPVs. Their characteristics include the following:

• Low specific fuel consumption from partial to full power • Reasonably low weight • Reasonably limited size • Excellent service history and good logistics support • Lend themselves to automation • Can be shock resistant • Possible to reduce acoustic signature



• Simple overall design integration • Low risk • Acceptable acquisition and life cycle cost

Conversely, high-speed diesels are limited in available power and cannot be continuously operated at very low power levels. Medium speed diesels are heavier than high RPM diesels, but have lower fuel consumption. They have advantages in terms of maintenance and reliability. Because of their weight, medium speed diesels are more likely to be employed by low speed OPVs than high speed SLCs. Modern diesel engines incorporate new concepts, based on various criteria, including:

• Reliability when operating • Good maintainability • Economy • Ecology – reduced emissions of CO2, NOx, SOx, VOCs

6.3.2.2 Gas Turbines Gas turbines are usually compact and low-weight units with good acoustic properties. The specific fuel consumption is generally higher than that of diesel engines, the time between overhaul is lower, and the cost of overhaul is much higher. Gas turbines are available in distinctly limited step functions of power. They require large air intakes and exhausts which have a significant influence on topside arrangements.

The advantages are:

• Good availability • Good reliability when running • Ease and simplicity of automation and control • Provide high power/weight • Very fast response to regime changes • Low necessity of personal attention • Low level of vibrations • Good modularization possibility

6.3.2.3 Combination Gas Turbine/diesel Engines Combining gas turbine with diesel engines in a power system offers the opportunity of gaining the best from both systems. Typical systems utilize the diesel for low power operations to take advantage of their low operation and maintenance costs and utilize the gas turbine operations that require high power output. The combination may either be through a CODOG system or a CODAG system. The former system is the least complicated as the system operates either Diesel or Gas turbines. In a CODAG system where both Diesel and Gas turbines are required to operate simultaneously power management is more complicated. The operating profile, as well as signature requirements for typical speeds, should be carefully scrutinized when making the choice of power systems. Typically acquisition cost and LCC will have to be balanced with weight and speed and other operational requirements. Considerations may include loitering speed, IR signature modes (e.g. low speed – low signature), portion of time spent at top-speed, etc. For specialized projects, novel combinations of power systems and propulsors may offer needed characteristics. An example of this may be combining diesel engines driving propellers with a center shaft powered by a gas turbine driving a water jet.



6.3.3 Propulsors 6.3.3.1 Introduction The main propulsion units for small ships are generally:

• Fixed and controllable-pitch propellers • Fully cavitating and surface piercing propellers • Waterjets

In recent years, azimuthing propulsion systems have been utilized on a limited basis on small ships, because of the enhanced maneuverability they offer. The main considerations when choosing propulsors are:

• Hull shape/draft/geometrical constraints • Efficiency • Appendage drag • Reliability and maintainability • Hydroacoustic performance • Cost

6.3.3.2 Fixed-Blade Screws The use of fixed-pitch propellers is restricted to those kinds of ships that do not require operating efficiently over a wide range of speeds. The principal reason for selecting this kind of propulsor is the relatively low price and simplicity. 6.3.3.3 Controllable-Pitch Propellers Controllable-Pitch Propellers (CPP) have the ability to change the angle, and thus the average pitch, of the blades. This is accomplished using a hydraulic system that sends oil to the bossing of the propeller through the shaft. Depending on the signal that is sent from the bridge, the position of the blades will vary, introducing more or less pitch in the blades.

In case of a failure of the hydraulic system, the blades are locked in a determined position (known as the failsafe position), effectively creating a fail-safe fixed-pitch propeller. CPP permits the propeller to achieve high efficiency over a range of speeds. They may also be used by the Main Engine control system, for example, offering slow drive options with gas turbines. In addition to this, the RPM may be varied for the same ship speed, making hydroacoustic detection more difficult and improving cavitation performance. Usually, CPPs have a larger bossing than fixed-pitch propellers, which may be detrimental to hydroacoustic performance and propeller efficiency. 6.3.3.4 Waterjets

Waterjets have a great share of the high-speed market, but have not yet been used extensively in SLCs and OPVs. They have the following advantages:

• Very high efficiency at high speeds (from 30-35 knots and above) • Low costs of installation • Low costs of maintenance • High reliability • Excellent maneuverability both in low speeds and high speeds • Low draft (they don’t protrude under the keel of the ship)



• Low appendage drag • Low noise

The noise generated by waterjets is generally a broadband noise that is not easily detectable by mine systems. 6.3.3.5 Electric Azmuthing Propulsors Electric azmuthing propulsors offer 360° control of thrust. Because they can be aligned with the water flow azipods also tend to provide better efficiency than conventional propulsors. If electric drive is used the use of azipods provides great flexibility in the general arrangement, since the engines and propulsors no longer have to be connected by a shaft. Electric azmuthing propulsors are very heavy, complex and relatively costly. The uses of heavy azipods on high powered small ships will be impossible because of the impact of azipod weight on the overall longitudinal center of gravity, required hull longitudinal center of buoyancy, or trim. 6.3.4 Propulsion Systems 6.3.4.1 Introduction Most current SLCs and OPVs have multi-shaft Diesel, CODOG, or CODAG propulsion systems. The choice of propulsion plant will vary depending on mission requirements and national preferences. It is feasible to employ any of these propulsion systems with either propellers or waterjet propulsors, or in some cases with a combination of propulsors. A brief overview of the alternative systems follows. 6.3.4.2 Diesel One or more medium or high-speed diesel engines can drive fixed or variable pitch propellers or waterjets. SLCs or OPVs can have 1 to 4 shaft lines. Most existing fast attack craft have employed 3 or 4 shaft diesel plants using one high-speed diesel engine per shaft and high RPM fixed pitch propellers. These propulsion plants are lightweight and compact, but lack operational flexibility as these ships are incapable of sustained loiter operations. Most OPVs have employed twin-screw diesel plants using one or two medium speed diesel engines per shaft and controllable pitch propellers to maximize operational flexibility. 6.3.4.3 CODOG/CODAG Outside the Soviet Union, large SLCs generally employed twin-screw CODOG propulsion plants. These used high-speed diesel engines for low to medium speed operations and one or two boost gas turbines for high-speed operation. Controllable pitch propellers were used to provide efficient operations at all speeds, and were used for reversing. By comparison, the Soviet Union employed triple screw CODAG propulsion plants, the latest of which had diesel powered shafts outboard with a gas turbine powered shaft on the centerline. The diesel shafts were used for transit, while the gas turbine could also be used for high-speed operations. These SLCs also had APUs for low speed loiter operations. The U.S. Coast Guard has recently studied a similar triple shaft CODAG propulsion plant with high-speed diesels outboard and a centerline boost gas turbine driving a waterjet for high-speed operations. The outboard shafts were studied using either controllable pitch propellers or waterjets. The conclusions were as follows:

- Waterjet propulsion resulted in lower appendage drag, - Waterjet propulsion was more efficient at boost speed,



- Propellers were more efficient at transit speed, - The difference in weight and acquisition cost were minimal, - Waterjets provided higher flank speed, but lower transit speeds, - The LCG of the waterjet plant was somewhat further aft than that of the propeller plant

Because the operational profile was primarily oriented towards low speed loiter operations the efficiency of the propellers had minimal impact on total ownership cost. An alternative operational profile might have resulted in greater importance being given to transit performance. Thus in this case, the recommendation was to use waterjet propulsors. A more conventional operational profile might have led to an alternative recommendation for controllable pitch propellers outboard vice waterjets. 6.3.4.4 All Electric Ship Due to cost, weight and space considerations, the all-electric ship concept is uncommon in most SLC and OPV applications and will not be elaborated upon herein. 6.4 Standardized Marine Environmental Protection Equipment 6.4.1 Introduction The need for maritime environmental protection (MEP) equipment onboard small naval ships derives, from the growing human pressure over the marine environment, including coastal inshore-generated pollution, over-fishing, offshore exploration of petroleum and other mineral resources and ship-generated pollution. The large majority of ship-generated pollution is caused either by accident (accidental oil spills or loss of dangerous cargo) or illegal voluntary spills (tanker tank washing, discharge of untreated bilge waters and disposal of dangerous waste in order to save the cost of waste processing). The use of old technologies and waste stream management procedures (sometimes the complete lack of a procedure other than direct discharge to the environment) is also a problem, especially in the least-developed areas of the world. Naval ships’ quota of responsibility in both accidental and voluntary spills is negligible. However, from the moral point of view, and as ship owners, coastal states are responsible for setting an example of impeccable environmentally conscious behavior. Therefore, all rules and regulations set for the marine oil and mineral resources exploration, transportation, commercial, leisure and fishing industries should also be enforced in all state-owned ships. The issue of standardization of equipment and procedures within the universe of government-owned shipping frequently turns out to be a major problem. Usually, other than naval ships, the government owns a very wide range of ships such as oceanographic and hydrographical research ships, harbor administration and support ships, tugs, life-saving craft, pollution control boats, cable-laying ships and others. Frequently, these vessels are purchased, operated and maintained by different governmental agencies, with different design and management bureaus, and they frequently have different approaches to the issue of compliance with MEP regulations. On the other hand, in most nations with small navies (and accordingly small budgets), maritime and coastal police and constabulary duties are carried out by the navy, which ends up operating both ocean-going ships, such as frigates and OPVs, and small fisheries and coastal patrol boats. Due both to the visibility of long-term sea-going operations and large crews, the priority of MEP compliance given to large ships is usually much higher than small ships. In addition, large ships can usually accommodate the implications of MEP compliance (by fitting MEP equipment and adopting sound waste stream management procedures) with negligible effects on mission profile and ship performance. Smaller ships, however, may suffer significant range and speed restraints due to mission duration limitation, increase in weight, and equipment and storage space requirements.



6.4.2 Problem Definition – Evaluation of Waste Stream Produced by Small Ships A simple exercise (Appendix 9.9) was carried out to illustrate the physical impossibility of storing onboard all components of the waste stream, and specially the liquid components. In accordance with the estimated values, the proportion of liquid waste to solid waste is huge, both in weight and volume. As a result, it is generally necessary to discharge a very high percentage of this stream either in the treated or the untreated form. The results also show that most categories of the solid waste stream take little weight. Therefore, and assuming that the ship is operating in an area where discharge is prohibited, the use of volume reduction measures and subsequent storage onboard should be much simpler and cheaper than destroying or processing solid waste. 6.4.3 Shipboard Waste Abatement Policies The most efficient shipboard pollution abatement policy is reduction at the source by using technologies and procedures with little waste generation. It is also obvious that it is not possible to reduce waste stream generation down to a level where the problem of waste management becomes negligible. Appendix 9.10 identifies waste stream categories that need to be considered. AMMEP-4/ANEP-59 defines the main guidelines for waste management based upon the issue of waste stream segregation or mixing:

a) When some waste streams are permitted to be discharged into the sea in accordance with MARPOL and national regulations and others aren’t, they should not be mixed.

b) When different waste streams are permitted to be discharged into the sea in accordance to MARPOL and national regulations, they can be mixed.

c) Waste streams which, in accordance with MARPOL and national regulations, are not permitted to be discharged into the sea must be retained onboard until they can be disposed of in port, and they must not be mixed with each other.

In accordance with AMMEP-4/ANEP-59, Table 6.4-1 lists the waste management strategies that should be addressed.

Table 6.4-1

Waste Management Strategies (AMEPP-4, Summary of Table 5A)

Order of priority Scenarios for waste management and generation

1 Source reduction or elimination

2 Minimization

3 Shipboard reuse or recovery

4 Shipboard treatment

5 Collection, hold, transfer to a supplier or port facility

6 Collection, hold, discharge at sea when legally allowed

Source reduction or elimination refers primarily to technology. As an example, the total replacement of CFCs by non-ozone depleting agents eliminates the problem at the source. Minimization of waste generation is related to process and procedure efficiency. As an example, propulsion machinery plants, and the associated operation procedures, have improved considerably.



Therefore, most modern propulsion plants, when adequately operated, produce much lesser waste streams than older plants. Shipboard reuse and recovery is still of very limited use, as it depends also on technology. Current reuse and recovery technologies, for paper and cardboard for example, are not cost-effective onboard. They are also weight and space ineffective, and they are likely to become feasible in large ships long before they are in small ships. On the other hand, shipboard treatment is essential to ensure a drastic reduction in the waste stream percentage of volume and weight that will have to be retained onboard. Collection, hold and transfer is a method of dealing with the types of waste that are difficult to treat and are dangerous to the environment, such as medical waste and hazardous waste. They must not be discharged without complex processing or a destruction procedure. Finally, collection, hold and discharge to sea, when legally allowed, is the simpler way to deal with waste that must not be discharged very close to shore, but which, in essence, is not dangerous to the environment. The obvious problem of this strategy is having to deal with a large storage and handling capacity. 6.4.4 MEP Requirements in Small Ship Design AMMEP-4/ANEP-59 describes the application of the different waste management strategies for the different waste streams, deriving from the legal requirements set out by MARPOL 73/78. However, it must be noted that some national regulations may differ from MARPOL 73/78. The practical issue is accommodating waste management strategies to the mission profile in order to produce an evaluation of the waste stream, and, therefore, define the requirements for the MEP equipment that should be fitted onboard a particular ship. Where an analysis of the waste stream generation and management onboard small ships is concerned, it may be assumed that all reasonable measures for source reduction/elimination, source minimization and shipboard reuse and recovery (scenarios 1, 2 and 3 of Table 6.4-1) have already been implemented. This way, from the designer’s point of view, the waste stream is a reality that must be dealt with by resorting to scenarios 4, 5 and 6 of Table 6.4-1, which will require some form of MEP management plant. It depends on the type of waste stream, as described in AMMEP-4/ANEP-59, Chapter 8:

a) Oily water. Typical onboard treatment starts by pumping bilge waters from machinery space bilges into a bilge water holding tank. The oily mixture is treated by passing it through a bilge water separator. The separated oil is collected in a sludge tank, to be disposed of at port facilities. The effluent is controlled by an oil content monitor, according to IMO resolution MEPC 60(33), and discharged into the sea or returned to the holding tank. Disposal to port reception facilities implies that the pipes are fitted with flanges, referenced in IMO/STANAG 4167.

b) Sewage. Small ships with a small endurance at sea may be equipped with a sewage holding

tank for discharge into the sea or disposal to port facilities. In such cases, it is preferable to have a vacuum collection and holding system to minimize stream volume. In most ship operation profiles, however, the weight/volume of sewage is significant, and a sewage treatment plant becomes necessary. There are different systems available for sewage treatment, some of them including grey water treatment, but the system’s operating principle is similar, as sewage is submitted to physical separation, chemical treatment (oxidation), and/or aerobic biological treatment. Sludge is retained onboard prior to discharge (where permitted) or destruction by incineration, and the treated liquid is disinfected and discharged.



c) Grey water. There are currently no MARPOL regulations that prohibit the discharge of grey water, but some sewage treatment systems accept grey water, which is chemically and/or biologically treated together with sewage.

d) Food. Food waste is usually collected in the galley, or in a processing room in the galley’s

vicinity, and submitted to grinding and/or pulping with seawater or fresh water. In accordance with current MARPOL regulations, there are no limitations to the discharge of ground and/or pulped food waste, but solid separation may be required for coastal operations. The solid residue may be stored onboard as disposed of in port or destroyed by incineration.

e) Other solid waste. MARPOL regulations prohibit the discharge of medical waste and hazardous

substances at all times. Therefore, they must be stored onboard and disposed of in port; however, it is preferable to store them after crushing. The same applies to plastics, but they may also be shredded and compacted with heat prior to storage onboard. For all other types of solid waste (metal, glass, paper and cardboard), the same MARPOL regulations apply, but the use of collection containers is preferable because glass and metal must be ground by crushers/ shredders if an efficient volume reduction is to be achieved. Paper and cardboard are usually much easier to handle, and they may be pulped and discharged, ground and compacted for recycling, or even destroyed by incineration. With this process, adequate sets of collection containers should be placed close to the waste generation sites. When the liners of the collection containers are filled, they must be removed to a solid waste processing area and replaced by empty liners.

6.4.5 Proposal for a Baseline MEP Equipment Plant for Small Ships The overall issue of MEP compliance should always start with a waste management plan, implementing all the waste management strategies of Table 6.4-1 in the correct order of priority. Hence, the waste recovery, storage and processing plant onboard should be no more than one of the different aspects of a comprehensive waste management policy. The standardization of MEP equipment plants for small SLCs and OPVs benefits from the fact that, in essence, both the problem of MEP compliance and all typical technical solutions are not specific to military shipping. Hence, and taking into consideration specific military requirements (like shock resistance), it is frequently acceptable to incorporate COTS (commercial off-the-shelf) solutions for ships of the fishing, transportation and recreation industries of relatively similar size and crewing levels. Taking into consideration current practices in modern navies, the following baseline proposal for a small SLC or OPV should provide complete compliance with MARPOL regulations and probably with most NATO countries’ national legislation:

f) Oily water. A dry bilge system is preferable because it is much cleaner than the wet bilge system and because it brings along advantages where fire fighting is concerned. However, it is not possible to fully prevent oil leaks into the bilges from occurring, and therefore provisions should be made to fit bilge pumps to deal with such situations. It is advisable to fit used oil tanks separately from oily water holding tanks. Oily water may be treated by OWS (oily water separators) and the effluents checked by OCM (oil content meters) to be discharged overboard. Disposal ashore of the separated oil, together with used oil, is always necessary. To comply with the requirements, the discharge pipes are to be fitted with flanges, referenced in IMO/STANAG 4167.

Note: If the ship’s expected area of operations and operating profile suggest the possibility of

long-term operations in environmentally sensitive areas, it is advisable to contemplate adequate system redundancy levels.

g) Sewage. Very different sewage systems are available as COTS solutions, ranging from simple

toilets with individual holding tanks to complex biological and chemical treatment systems.



h) Grey water. Most COTS solutions contemplate only gravity collection to a holding tank system

with a pump which is activated by a level sensor, discharging overboard. i) Food. There are simple COTS galley sink pulpers, discharging to a holding tank or to the ship’s

STP, or separate pulpers/shredders. Generally, food waste is submitted to grinding and/or pulping with seawater or fresh water and is discharged overboard. Internal water operations, however, deserve further investigation on this issue.

j) Other solid waste. The complex separation and separate processing currently considered to be

adequate for large ships is too demanding on small ship’s weight and space resources. In any case, in order to ensure compliance with MARPOL regulations, the ship should be equipped at least with separation bins for plastics, metal and glass, hazardous waste and medical waste. These should be stored onboard, and preferably ground and/or compacted, but not necessarily. It is also necessary that the procedure is compatible with the storage space available. To contain storage requirements at reasonable limits, the enforcement of a waste management policy considering waste generation reduction at its source is essential.

6.5 Standardized Replenishment at Sea (RAS) Equipment 6.5.1 Introduction From the strategic viewpoint, one of the most important capabilities of a naval force is the ability to sustain operations at sea, thus remaining for long periods in the area of operations. However, the extent of time on station depends on the rate of consumption of a variety of consumables which may include provisions, fresh water, fuel, medical stores, spare parts and ammunition. From a theoretical point of view, it is possible to prolong, almost indefinitely, the extent of the ship’s time on station by replenishing it when necessary. As a result, the limiting factor has become the crew’s endurance due to physical and mental fatigue. The necessity to replenish fuel and other stores at sea derives from the balancing of the ship’s tanks and stores capacities against their impact on ship performance for a given mission profile. Each particular SLC/OPV design must take the design issues relating to endurance into account so that operational requirements are fully met. On the other hand, it is fairly reasonable to provide naval combatants with replenishment at sea (RAS) capabilities in order to increase operational flexibility. It also allows the force to remain at sea for a longer period of time. Most SLCs and OPVs are designed to operate in coastal waters, in close proximity to replenishment facilities ashore. In cases where the mission profile requires these ships to carry out operations far from home or allied ports for long periods, it is likely that some RAS arrangements will be necessary to provide fuel, stores and ammunition, and allow for the evacuation of injured or sick personnel. In the particular case of NATO forces combined operations, for which interoperability is an essential requirement, it is also necessary to take into account the commitment not to impose severe restraints on the operational commander, which may be the case if one of the ships is severely limited in endurance and its RAS capabilities are not compatible with the RAS equipment of the force’s fleet replenishers. 6.5.2 Problem Definition – Evaluation of Replenishment Requirements Applicable to Small Ships Replenishment at sea was developed as a ship design issue relating to blue water operations, which may not be necessary for small ship operations. In order to quantify fuel and stores requirements, a simple exercise was carried out (Appendix 9.11). This exercise pointed out that, in general, solid stores do not present a major problem, but there are enormous problems associated with liquid stores, particularly fuel.



In the present day, fresh water supply is seldom an important issue, because technology has provided a weight, space and cost-effective solution in the form of reverse osmosis distilling plants. A problem exists, however, when the ship operates in a polluted water environment. Under these circumstances, it may be dangerous to use seawater as the source for the production of potable water, and fresh water replenishment procedures may be necessary. The most significant problem is generally related to fuel consumption. Fuel consumption rate is highly dependent on the ship’s propulsion machinery fit and operational profile. The three solutions to the problem are RAS, large tank spaces, and frequent ashore refueling. Again, the results of the simple exercise carried out in Appendix 9.11 illustrate that the impact of this problem tends to be more important in smaller ships, as consumable stowage requirements represent a higher percentage of total ship weight and volume. It is important to note that, besides provisions, fuel and fresh water, other important items such as ammunition, helicopter fuel, personnel, spare parts, lubricating oil, clothing and canteen stores may be considered in a particular design’s RAS arrangements. However, most of those items are generally transferred to larger ships (frigate size and larger). Small SLC/OPV RAS arrangements tend to be limited to fuel and lightweight solid stores. 6.5.3 RAS Requirements in Small Ship Design In small ship design, RAS requirements may vary from one extreme to the other, meaning that no requirements whatsoever may be considered up to STANAG 1310 requirements. Taking a quick look at existing OPV and SLC designs, it is clear that in the majority of cases, ship designers decided to discard RAS arrangements, or to reduce them to minimal equipment fit, in order to save weight and reduce cost. It is also important to bear in mind that RAS operations require personnel and training, and that close ship-to-ship operations are inherently dangerous. The decision to abandon the RAS option is, therefore, often taken consciously to keep the ship’s operation as simple and safe as possible. In addition, most green water navies have decided to limit RAS procedures to astern refueling, an operation much simpler and safer than side-to-side replenishment. 6.5.4 Proposal for a Baseline RAS Arrangement for Small Ships It was noted that small ship’s RAS requirements may be extremely variable and, therefore, operational requirements should always be balanced against the advantages of RAS requirements for a particular ship. It should be noted, however, that fuel storage impact on small ship overall design generally increases as ship size decreases. It is obvious, on the other hand, that human factors associated with small ship operations are frequently the limiting factors for mission duration. Consequently it will be of no operational gain to fit a small ship with RAS arrangements, allowing it to operate for an unlimited period of time at sea, if crew fatigue becomes critical after a relatively short period at sea. However if continuous high-speed operations are necessary RAS will be required to extend endurance beyond a very short time. As a baseline proposal for small ship RAS arrangements, the most austere concept would simply be to cater for ship safety and emergency arrangements. For example, the Royal Australian Navy (Appendix 9.12) considered some form of fuel and solids receiving, using VERTREP, which would also be used for emergency procedures, for example, evacuation of sick personnel. 6.6 Composite Materials and Comparison with Other Materials Used for Naval Shipbuilding The present analysis compares composite materials with the materials that are commonly used for naval shipbuilding in terms of weight, mechanical properties, and cost of production and repair. In particular, the following structural materials will be considered:



• Steel • Non-Magnetic Steel • Aluminium Alloy • Composite Materials

6.6.1 Steel For decades, steel has been, and still is, the most common material used in the construction of SLCs, OPVs, larger naval ships and merchant ships. In the last 20 years, new types of steel have been developed with increased mechanical characteristics. The elastic limit has almost doubled from about 230N/mm2 to over 500N/mm2. New metallurgical processes have allowed the development of new microstructures, new chemical compositions, and new thermal treatments while maintaining welding properties. For example, pre-heating activities previously required before welding high strength steel have been cut. Moreover, in the last decade, the price of raw materials has dramatically dropped, up to about 40% for the cost of stainless steel. Steel developments have given an:

• Increase of the mechanical properties, especially in the elastic limit and in the ductility.

• Reduction of the grain dimensions, with increased assured toughness up to 60°C, and increased fatigue resistance.

• Change in chemical compositions by using the best building technologies, such as cold deformation welding.

Steel undergoes many changes during cutting, shaping and welding. Especially in the past, welding activities would locally shrink steel due to the percentage of alloy elements necessary to provide steel the required strength. In fact, these alloy elements had high hardening characteristics. The nominal chemical compositions, the equivalent carbon (Cev), and the mechanical characteristics for traditional steel types (S275J2G3, S355J2G3), modern steel types (those used in new construction), and new advances that are currently under testing are listed in Table 6.6-1. S 460 NL and S500 QL steels can easily be welded by traditional shipyard procedures (SMAW, MAG, SAW). Due to the characteristics of the basic materials, failure of the test samples occurred outside of the joint seam. The welding procedure for the S 550QL and S690QL steels, which contain a chemical balance able to generate quenching structures, must be precisely defined in order to carefully control the diffusible hydrogen during welding and pre-heating. The above steels up to 18-20 mm thick can be welded without pre-heating by using either the SAW or the MAG welding procedures, with a low diffusible hydrogen percentage.



Table 6.6-1

Material Composition and Mechanical Properties

STEEL CHEMICAL COMPOSITION (%) (*) MECHANICAL PROPERTIES (2)-(3)

C Mn Si P S N Al Nb Ti Cev(1) REH(M

pa) Rm(mpA) A(%) KV(J)

S275J2G3 0.18 1.50 - 0.035 0.035 - - - - 0.40 >275 410÷560 >13 AT= - 27°C >27

S355J2G3 0.20 1.60 0.55 0.035 0.035 - - - - 0.45 >355 510÷680 >13 AT= - 27°C >27

S460NL UNI EN10113-2 fine grain and killed (4)

<0.20 1.0+1.7 >0.60 >0.030 >0.025 >0.025 <0.20 Total

<0.05 <0.03 0.4÷0.5 typical values

>460 550÷720 >17 At= - 50°C >27 AT= - 20°C <47

S500QL UNI EN 10137-2 fine grain normalized (5)

0.42÷ 0.52

>500 590÷770 >17 AT= - 40°C >30 AT= - 20°C >40

S550QL UNI EN 10137-2 grain quenched and tempered (5)

0.49÷ 0.55

>550 640÷820 >16

S690 QL UNI EN 10137-2 grain quenched and tempered (5)

<0.20 <1.70 <0.80 <0.020 <0.010 <0.015 <0.018 <0.06 <0.05

0.50÷ 0.60

>690 770÷940 >16

Note: (*) maximum values (1) Cev = “ equivalent carbon” = % C+ %Mn + %Cr + %Mo + %V + %Cu +%Ni 6 5 15 (2) Cev = K x Reh with K values 14 ÷ 16 (3) thickness of plates= 15 mm (4) other elements of the composition (%) V = 0.20 – Cr = 0.30 – Ni = 0.80 - Mo= 0.10 – Cu= 0.70 (5) other elements of the composition (%) V = 0.12 – Cr = 1.50 – Ni = 2.0 - Mo= 0.70 – Cu=0.50 - B=0.0050 - Zr=0.15



6.6.2 Aluminium Alloy While steel properties have improved over the years, there has been no major change in the composition of aluminium alloys, with the exception of the addition of a few 5000 and 6000 series alloys. In particular, due to their good resistance to stress corrosion, AA5083 alloys in different grades (commonly H321) are the aluminium alloys commonly used for shell plating, and all other parts of the ship in direct contact with seawater. Parts of the ship not in direct contact with the water (such as the superstructure) can be built with alloys in the 6000 family. These alloys are also used for extruded profiles. A big problem with aluminium alloys is the softening of the heat affected zone (HAZ) during welding. This significantly reduces the local yield and fatigue strength. The yield strength of an alloy can be reduced by about 50% by welding. A careful welding design (in terms of positioning, procedures, etc.) can partially avoid these problems. Aluminium alloys have a low resistance to temperature (200° softening point and 650° melting point), leading to a requirement for thermal protection in all designated fire hazard areas. The increased weight of this insulation requires attention at the outset of the design process as it can be significant. 6.6.3 Composite Materials The term “composite materials” is a generic term that has previously been used to indicate Fiber Reinforced Polymers (FRP). In particular, FRP has come to mean polyester resin and glass fiber. This has become the standard material used for small and medium-sized boats. In recent years, the use of new advanced materials (i.e. carbon fibers with epoxy resin) allows a considerable reduction in weight, increasing stiffness, strength and performance. But these improvements can be achieved only by means of an accurate knowledge of the behaviour of the new composite materials. Carbon fibers are much more costly than FRP. It is necessary to take into account that one of the characteristics of all the composite materials is the anisotropy, which is exaggerated in the case of advanced materials (carbon, aramid fibers). The anisotropy properties can be suitable to create an optimized composite product where the appropriate volume fraction and orientation of stiff fibers have been carefully considered for a particular load. For these reasons, the optimal results can be obtained if the naval architect, the structural engineer, and those responsible for production work together from the beginning of a composite structural design. The following sub-sections summarize the wide variety of choices for the builders in terms of raw materials (fibers and resins) and various structural configurations and construction technology available today. 6.6.3.1 Resins Chemical Composition Formulation Polyester resin Wet lay up Each resin type can be Pre preg-resin Vinyl resin produced to every Adhesive resin formulation Coating resin Epoxy resin



6.6.3.2 Reinforcement Fibers Fiber Type Configuration Roving Fiber glass Each fiber type or fiber Warped Carbon fiber roving combination (hybrid), Unidirectional roving Organic fiber can be used to every type Multi-axial roving of reinforcement MAT to shorts fibers construction 6.6.3.3 Core Material for Sandwich Fabrication Foam variancy PVC Each material type can Honey comb Phenolic resin be used for every type of Polyurethane resin construction variance and Density Nomex Construction construction fabrication Thermoplastic polymer Cells Construction variancy dimension variancy Aluminum 6.6.3.4 Structural Configuration Choice The choice of raw materials has to be combined with design choices concerning the possible structural configurations. Membrane skin Single-skin solution Skin with low stiffened thickness Skin with high thickness without stiffeners Symmetrical skin Variance of the ratio Sandwich solution Unsymmetrical skin skin thickness/core

thickness

Stiffened sandwich Unstiffened sandwich 6.6.3.5 Constructive Methodology Choice The choice of raw materials and structural configurations has to be combined with the manufacturing methodology choice (manufacturing process). Mold Consolidation Type Hardening Modality Male Nothing ambient temperature Vacuum bag ambient temperature Vacuum bag low temperature Female Vacuum bag high temperature Autoclave high temperature



6.6.4 Fibers The main fibers available for applications in shipbuilding are: 6.6.4.1 Glass Fibers Glass fibers represent over 90% of all fibers used for industrial reinforced products because these fibers offer good performance in terms of:

• chemical resistance • mechanical characteristics • workability • cost

The most common fibers are the E-glass fibers while the best choice for structural strength are the S-glass fibers. S-glass fibers give an increasing tensile strength of about 25%, but at 5 to 6 times the cost of E-glass. 6.6.4.2 Aramide Fibers The most common aramide fiber is Kevlar, which has been developed and produced by Dupont. Kevlar is characterized by low weight and high tensile strength, but it degrades in sunlight and is difficult to manufacture for laminate applications due to its fiber wetability. 6.6.4.3 Carbon Fibers In comparison with the other fibers, the carbon fibers have the best strength and elasticity (Young’s modulus). However carbon fibers are very expensive. Some typical properties of fibers are shown in Table 6.6-2.

Table 6.6-2

Fiber Characteristics

Fiber Properties Units

E-Glass Aramide High-Strength Carbon

High-Modulus Carbon

E Modulus GN/m² 76 125 250 390

? Strength GN/ m² 2.0 3.3 3.1 2.2

? Density 10³ kg/m³ 2.6 1.4 1.9 1.9

Elongation to Fracture % 2.5 2.8 1.0 0.5

E/ρ GN/m²/10³ kg/m³ 29 89 132 205

? / ρ GN/m²/10³ kg/m³ 0.77 2.36 1.63 1.16

Fiber Diameter µ m 12 12 8 8

Composites with hybrid fibers, including glass-carbon, glass-aramid, aramid-carbon, etc, can also be developed with varying proportions of fiber types.



6.6.5 Resins The most common resins used in conjunction with fibers are: polyester resin, vinyl ester resin, epoxy resin and phenolic resin. 6.6.5.1 Polyester Resin Polyester unsaturated resins guarantee the easiest and most economic impregnation method for marine applications. The most common are orthoftalic and isoftalic resins. Isoftalic resins are typically preferred because they have better mechanical characteristics and lower water absorption. 6.6.5.2 Vinyl Ester Resin Vinyl Ester Resin is an unsaturated polyester resin. It behaves the same as polyester resin, but has improved mechanical properties and impact characteristics and is more expensive. 6.6.5.3 Epoxy Resins Epoxy resins have the best characteristics for naval applications (Table 6.6-3). They also contract the least during hardening. Their use is limited to high-tech products because of their high cost and the difficulty in working with them.

Table 6.6-3

Typical Values of Modulus and Strength of Unidirectional Laminates, Considering Vf≅ 0.50 (volume fraction of fiber)

Units Glass/Polyester Carbon/Epoxy Aramide/Epoxy

E1 GN/m² 35-40 190-240 65-75

E2 GN/m² 8-12 5-8 4-5

G12 GN/m² 3.5-5.5 3-6 2-3

s 1(t) MN/m² 650-750 850-1100 1100-1250

s 1(c) MN/m² 600-900 700-900 240-290

s 2(t) MN/m² 20-25 35-40 20-30

s 2(c) MN/m² 90-120 130-190 110-140

?12 MN/m² 45-60 60-75 40-60

6.6.6 Single Skin and Sandwich Configuration 6.6.6.1 Single Skin Single skin glass reinforced polymers (GRP) reinforced by “hat section” longitudinal and/or transverse stiffeners have been, and remain, the most common form of hull construction for GRP naval applications. In particular, this solution is adopted for the construction of shells, plating, decks, and bulkheads of small and medium hulls, but also for superstructures and funnels of large ships. For a typical detail of the structural configuration, see Figure 6.6-1.



Figure 6.6-1. Typical Single-Skin Construction 6.6.6.2 Sandwich Configuration The FRP-sandwich is built with two stiff faces that are separated by a light core material. The core material increases the bending strength and stiffness of the overall panel at only a small weight increase. For the configuration and the stress distribution in the panel structure, see Figure 6.6-2.

Figure 6.6-2. The FRP-Sandwich Principle: Two Stiff Faces Separated by a Light Core Material Today, the sandwich solution with high-strength fibers is used to obtain high performance. 6.6.7 Advantages of Composites The advantages of using composite materials are:

• Strength at low weight.

• Little or no maintenance.

• Ability to use anisotropy with the ability to tailor the fiber proportions.

• Ability to build fully non-magnetic structures. This is required for the construction of mine sweepers or mine hunting vessels.

• Transparency for sonar domes and masts.

• Sandwich panels provide excellent thermal insulation.

• The core can include radar absorbing material for radar signature reduction and/or ballistic protection.

σ τ Face

Core

Face



• Sandwich panels are also than “hungry-horse” stiffened steel panels. 6.6.8 Disadvantages of Composites The disadvantages using FRP materials are:

• High cost of some fibers and foam core materials.

- High shipyard fabrication costs.

• Need for expensive molds.

• Fire resistance: there are problems with reduced structural strength, heat transmission to other compartments, low toxicity and low emission of smoke. Using phenolic resin instead of an epoxy or polyester allows good fire performance in terms of fire resistance, while mechanical properties can be comparable to polyester resin, especially after curing in high temperatures.

• Reliability of the material properties due to:

- differences in production of the basic materials. - differences during lamination at the yard. - lack of reliable and consistent test methods.

• Necessity to shield the panels to prevent electromagnetic interference. • FRP lacks stiffness whereas carbon fibers are stiffer, but very costly.

6.6.9 Significant Experiences with FRP Solutions 6.6.9.1 New LCS for Italian Navy (Figure 6.6-3)

Figure 6.6-3. Italian Light Combatant Vessel

Fincantieri has built four new LCSs for the Italian Navy with the following main characteristics:

LOA 88,40 m LBP 80,00 m B 12,20 m Max Speed 25 knots

The superstructures of the first three ships are steel, while the fourth ship has FRP superstructure (indicated in Figure 6.6-4 by the colored area).



Figure 6.6-4. FRP Superstructure for Fourth Vessel This FRP superstructure is divided into three sections:

1. stern section composite of the hangar for the helo, trunk and funnel, extends from frame 36 to frame 63.

2. middle section the hangars for two crafts, located on the first level, and the probe, which is the second level. This part extends from frame 63 to 78.

3. forward section the bridge on the first level, and the structure on the second level, which provides the foundation for the mast.



For the construction of the sections, modular molds were built to obtain an easy and speedy process to build the superstructure subdivisions. This construction process allows for parallel manufacturing of many individual panels, providing the ability to quickly assemble the sections. Figure 6.6-5 shows the subdivision of the molds and the assembling sequence of the sections.

Figure 6.6-5. Composite Assembly Sequence The structural configuration adopted for the construction of the superstructure is:

• single skin reinforced by stiffeners (see Figure 6.6-6) • sandwich configuration reinforced by stiffeners (see Figure 6.6-7)

Figure 6.6-6. Single Skin Reinforced with Stiffeners



Figure 6.6-7. Sandwich Construction Reinforced with Stiffeners

The panels were made with a significant use of high-tech hybrid materials (glass fibers-carbon fibers and glass fibers-kevlar fibers in unidirectional, roving mat), while PVC was used for the core. The connection of the superstructure with the hull of the vessel was performed by means of a contour flange (side FRP) interfaced with a metallic flange (side hull). The two flanges are joined together by bolts. For fire protection, the internal side of the structures, in both the single-skin configuration and sandwich configuration, have been protected by glass wool. Both solutions had been certified by R.I.Na. (Registro Italiano Navale). Comparison studies were performed to define the best solution to adopt for ballistic protection. The objectives were:

• to obtain a laminate with a high percentage of aramidic fibers mixed with glass fibers. • to obtain an armour with minimum weight.

The FRP configuration allows a reduction of weight of about 50% over steel. 6.6.9.2 The Visby Corvette (Figure 6.6-8)

Figure 6.6-8. Visby Corvette



The main characteristics of the Visby corvette are:

LOA 72,00 m LBP 61,50 m B 10,40 m Displ 600 t Max Speed 35 knots

In October 1995, the Swedish Materiel Administration and Kokums AB (Karlskrona shipyard) signed a contract for the design and construction of two Visby corvettes. The most important performance requirements were:

• Low weight • High strength • High impact resistance and damage tolerance • High shock resistance • Low signature to meet the stealth requirements • EMI shielding • Low acquisition and cost maintenance

The investigation of the designs indicated that the solution that could guarantee the requirements was based on a HS carbon fibers/vinyl ester composite (CFRP) in a sandwich construction. Typical composite FRP sandwich solutions from Kockums can be summarized as follows:

• Core of rigid PVC foam (thickness 30-90 mm, density 60-240 kg/m3, high shear stiffness, high shear strain, favourable fatigue properties).

• Laminates (1-20 mm) with reinforcement fibers (unidirectional or directional, glass or carbon) in vinyl ester matrix on each side of the core.

• Structural adhesives.

• Curved panels produced using wooden frames for the core planking and “in situ” infusion of the laminate.

• Flat panels produced on a vacuum table using the Kockums Vacuum Assisted Infusion (KVASI) method.

• Flat parts cut to shape and with holes using a NC waterjet cutting table.

• Large hulls built in sections with sectional joints.

• External surfaces with sharp edges and large extremely flat external surfaces. No “starved horse” pattern as for welded structures.

• Strict QA/QC procedures including training and testing. Typically, this results in 50% lower weight for the complete structure (hull and superstructure) compared to a conventional (high-tensile) steel hull with aluminum deckhouse. This can be used to increase speed, range or payload, or to reduce the necessary propulsive power. A balanced combination of these advantages is also possible. Additionally, the CFRP sandwich concept, as used for the entire structure of the Visby Class Corvettes, has a number of significant advantages over conventional materials as explained below:



Excellent mechanical properties (Table 6.6-4):

• High stiffness-to-weight-ratio => Lightweight design => Weight/speed/range/power allowance. • Good resistance to underwater explosions such as mines.

Stealth:

• Exterior shaping, extreme flatness and integrated radar absorption where necessary => Low magnetic signature.

• Built-in noise damping => Low hydro-acoustic signature. • Built-in thermal insulation => Low IR-signature. • Low weight => Low-pressure signature.

Cost efficient:

• Non metallic => No corrosion => Low requirements of maintenance => Cost effective. • Built-in non-structural properties => e.g. thermal insulation => No need for comfort insulation.

Table 6.6-4

Comparison of Main Materials for Use in Naval Vessels

MATERIAL PROPERTY

High strength steel Aluminium alloys FRP

Density ≈ 7800 kg/m³ ≈ 2700 kg/m³ Generally low, but depending on the fibers and the resins percentages

Young’s modulus ≈ 207 000 MPa ≈ 70000 MPa Generally low, but depending on the fibers and the resins percentages

Mechanical strength High Generally good but mech. properties are reduced in welded zone.

High strength in case of use of high strength fibers with optimization of fibers directions

Fire resistance Non-combustible material Low softening and melting points requires insulation

Generally combustible. Fire properties can be improved by adding inhibitors. Toxicity of smoke can remain a problem.

Corrosion resistance Low; protective coatings are necessary

Good for 5000 alloys. 6000 alloys can be used not in contact with sea water

Excellent

Cost of material Low Medium. Special extrusions can be most expensive

High, especially for high performance fibers also considering falling of carbon.

Production costs Low. Problems in case of low thickness (distortions)

Medium. Distortion from welding. Extruded structures are cost-effective

High, Generally it is also necessary to consider the cost of the mold which will increase the cost.

Repair Simple More difficult, re-weld are to be avoided

Very difficult.



6.7 Signature Management The following text describes some basic design guidance regarding signature management. To be able to describe the complete signature of a ship, the signature is separated into different signature categories above and below the water surface. The signatures of ships above water include optical, radar, emitted, and infrared, while underwater signatures include electric, pressure, acoustic, magnetic, and wake (see Figure 6.7-1). Technologies have evolved that allow a significant reduction in all types of signatures, but they are not always operationally effective or cost-effective. Tactics can also be a significant element in signature management. Therefore signature management should be a significant subject of discussion when developing a ships mission requirements. If, for example, there is a limited threat beneath the water surface, it is not worth the cost to minimize hydro acoustic signatures. Appendix 9.13 discusses the application of signature management techniques to the design of a 600-tonne corvette.

Optical sign.

IR- sign.

Emitted signals

Acoustic sign.

Magnetic signature

Pressure sign.

Electric sign.

Other sign.

Wake

Radar- signature Air

Underwater

Other sign.

Figure 6.7-1. Signatures

Signatures can also be divided according to their physical phenomena in operation, for example: Pressure waves:

• Noise, Sounds • Pressure

Electro Magnetic Waves:

• Radio and radar waves • Heat radiation • Visible light • Eletromagnetic field disturbance



These physical mechanisms produce different signatures that can be detected with different types of threat sensors. For a truly stealth craft, all threat sensors must be taken into account. This, once again, is connected to the type of mission and the threats to the ship. This may sometimes result in a conflict of design initiatives since, for example, it may prove hard to reduce the radar, infrared and optical signatures at the same time. However, the design and choice of material that is suitable for reducing the radar signature may also often be suitable for reducing other signatures. 6.7.1 Radar Cross-Section Signatures (RCS) RCS Management must consider the type of threat, surface, airborne, or space based, the frequencies of the sensor, and the operational objective, i.e. to prevent detection, classifications, targeting, tracking, and/or to improve decoy effectiveness, as well as the naturally cluttered sea or coastal environment. When RCS is important, a simple closed hull shape, with all equipment inside the hull, is the optimum solution. By comparison, conventional warships have their equipment, weapons etc. placed on deck, deckhouse or on the mast. The equipment reflects the radar pulse in several directions, resulting in multiple reflections between equipment and the hull. There are three different methods to design a ship in order to reduce its RCS signature. The different methods each have their advantages and disadvantages. Cost and operational realities ultimately determines how much the radar signature can be reduced. The three different methods are:

1) Using shaping to scatter the reflection of the radar 2) Using radar absorbent material (RAM) to reduce radar reflections 3) Using transparent material in way of own ship antennas

Transparent materials with frequency specific characteristics can be used to hide components that transmit signals at a particular frequency. These materials are often used in way of emitters located within enclosed masts. Radar screens can be used to hide air intakes and other cavities. A poorly designed radar screen, however, may result in high radar cross-signature. Radar Absorbent Material is frequency dependent. It is expensive and most often used when necessary to mask particular reflectors. The most used method of reducing RCS is shaping. This reflects the radar wave in any direction other than the incident direction. To use this method, electric conductive flat surfaces with normals pointing in known directions are the easiest to implement. The reflection angle, φ, shown in Figure 6.7-2, is often based on the angle appropriate for both RCS and the hull’s rolling characteristics.

Figure 6.7-2. Reflection Angle As described in Section 6.7.6, the stern wake may also contribute to the RCS, especially at higher speeds when the stern wake increases.



Some simple geometries and their contribution to RCS signature are shown in Table 6.7-1. A standard rule to lower the RCS is to use simple shapes, since more complex shapes typically have higher signatures. In any case, the main objective is to avoid corners and edges.

Table 6.7-1

Geometries Contribution to Radar Cross-Section (RCS)

Geometry Type Freq. Dep.

Size Dep.

Maximum RCS

Note

Cubic corner reflector with three surfaces

F2

L4

2

4a12

λ

∗π∗=σ

Highest RCS: due triple reflection

Corner reflector with two surfaces

F2

L4

2

22 ba8

λ

∗∗π∗=σ

Second highest RCS: due double reflection. Week variation with θ, Strong variation with φ

Flat surface F2

L4

2

22 ba4

λ

∗∗π∗=σ

Third highest RCS: high RCS with perpendicular angle of entrance, decreasing quickly when the angel goes from perpendicular

Cylinder F1

L3

λπσ 2 ba ∗∗∗=

Common contribute to heavy RCS over large angle of aspects. Decreases quickly when elevation angle (φ) goes from cylinder surface normal.

Sphere F0

L2

2a∗π=σ

Common contribution to heavy RCS in many angles. Big openings in the targets surface/body can give the same contribution. The energy is spread mainly in two directions.

Straight edge, perpendicular to corner

F0

L2 ( ) 2

i L,f ∗θθ

θ= angle of entrance in plane

θi=angle between surfaces

A single curved plate shows this contribution when the radius of the curvature goes to zero.



Geometry Type Freq. Dep.

Size Dep.

Maximum RCS Note

Curved edge, perpendicular to corner

F-1

L1 ( )

λ≥

λ∗∗θθ

a2

a,f i

A double curved plate shows this contribution when the smallest curvature goes to. The function ( )if θθ , is the

same as in the case with a straight edge.

F= Radar Frequency Dependency L=Size Dependency (a,b,L) λ =Radar Wave Length σ = Maximum Radar cross-section

6.7.2 Infrared Signature (IR) Infrared signatures can be divided into two different sources, internal and external. Examples of internal sources include engines, air inlets and outlets, while external sources include solar heating. For a successful reduction in IR signatures, both internal and external sources need to be considered. The IR reduction of ships can be divided into four levels, which are:

1) No reduction (baseline platform) 2) Basic cooling of visible exhaust duct metal, and skin cooling with available means (NBC water

wash) 3) Exhaust duct cooling, exhaust gas cooling to 250 °C, skin cooling with available means 4) Exhaust duct cooling, exhaust gas cooling to 150 °C, full skin cooling (with dedicated water wash

for skin cooling) As with all signatures, the final selection of IR level depends on the perceived threat and the system cost. Thermal sensors can detect very small differences in temperature. Therefore the IR signature management strategy has to be carefully considered. Most modern naval ships have achieved level 2 or 3, although several have been designed to level 4. To reduce the signature to level 4, the intakes and exhaust air outlet must be well designed since the intakes and outlets very quickly adapt to local temperature. For air intakes, the temperature will be the same as for the surrounding air, thus creating a temperature contrast with the hull if the hull temperature is higher than the air temperature (which is often the case because of solar heating). The effect can be reduced by carefully positioning the air intake and by increasing the diameter of the intake, thereby reducing the airflow. The exhaust gas outlets from the main machinery (both low speed and high speed) can be several hundred degrees. One way to avoid these infrared hotspots is to cool the exhaust temperature. This can be partially achieved by injecting seawater into the exhaust gas. The seawater injection will also contribute to a washout of the exhaust gas, which will reduce the number of particles emitted to the surroundings. Seawater combined with exhaust gas from the engines is corrosive and, thus, exhaust stacks must be made of a non-corrosive heat-resistant material like titanium. Another way to reduce the particles admitted to the surroundings is the humid air motor (HAM) technique in which water mist is injected directly into the combustion chamber. This reduces the NOx emitted to the air and, therefore, reduces the infrared signature of engine exhausts. The external sources, such as solar heating of the hull, should be compared to the background signature. To reduce the effect of the sun, the NBC water wash down system can be used to reach the first few levels of IR signature. To reach level 4 (and lower), the ship must be equipped with a system designed for full skin cooling. This system can, of course, also be used for NBC wash down, although it is more capable and precise than normal NBC wash down systems.



6.7.3 Acoustic Signature For small, fast, high-powered SLCs it will be very difficult to reduce the acoustic signature when operating at full power. However, for SLCs operating in mine threat areas, littoral and shallow waters, the acoustic signature may be very important. The hydro acoustic signature consists of propulsion noise, which can lead to global hull resonance, flow noise and noise from machinery and equipment. Vibrations generated by engines, gearboxes etc. are transmitted to the ship’s structure and further to the surrounding water, and will, together with the propulsion unit and flow noise, generate the hydro acoustic signature. The hydro acoustic signature is speed dependent. Reduced speed lowers the signature and is, therefore, a tactical issue. To minimize this signature, all equipment with non-static parts can be placed on isolation mounts. To avoid problems from accuracy of shaft alignment, main machinery and gearboxes can be placed on resilient mounted platforms. Engines and larger noise generators can be located within noise enclosures to minimize airborne radiated noise. To minimize the noise from the propulsion unit, propeller characteristics can be modified, including number of blades, load distribution, skew-back and propulsor material. However, it will often be impossible to achieve this for highly loaded, high RPM propellers. In some cases, waterjets may therefore provide better acoustic signatures than conventional propellers. That, again, depends on the mission profile for the ship as well as other design criteria. Pumps and other non-static equipment should be of the type that uses smooth pressure changes or smooth movements, i.e. they should not be of the pulsating type, which leads to vibration and noise in the ship. To minimize the radiated noise from the ship, noise enclosures, as well as fluid silencers, should be used where there is a need for them. 6.7.3.1 Acoustic Signature Above Water Surface This signature is seldom discussed since the cost to reduce the acoustic signature often is not proportional to the actual signature reduction. It can be useful, however, to reduce this signature, especially in archipelagos and for littoral emitting missions. Noise from the exhaust pipes can be reduced by exhaust air under water. This will, of course, increase the hydro acoustic signature, and is therefore a tactical issue. 6.7.4 Electromagnetic Signature When operating in littoral and shallow waters, the mine threat increases and, therefore, the magnetic and electromagnetic signature must be low for ships in these environments (Figure 6.7-3). The magnetic field from a ship consists of three elements: induced ferro-magnetic signature, permanent ferro-magnetic signature, and Corrosion Related Magnetic (CRM) signature. The induced part is always proportional to, and aligned with, the field surrounding the ship. The permanent part is a residual magnetism that acts as a magnetic memory. This part may be several times higher than the induced part and it may emit in any direction. The induced and permanent signatures can be reduced up to 80-95% by using a degaussing system. To further reduce the magnetic signature, non-magnetic materials can be used for the hull and ship components. Electrochemical corrosion occurs between electrically connected materials such as steel hull, bronze propeller, and corrosion protection systems. This causes an electric current in the seawater surrounding the ship. Th e current results in a magnetic field in the water and in the air, the CRM Signature. This field can be detected by airborne sensors, increasing the vulnerability of the ship. This electromagnetic signature, or galvanic signature, can be divided into Underwater Electric Potential (UEP) and Extremely Low Frequency Electric (ELFE). The UEP occurs by the potential differences in different materials, while the ELFE is a mode-dependent resistance in the bearings between the propeller shaft and the hull. This causes a modulated current that, in turn, broadcasts an alternating electric field at rotating frequencies and their harmonics. There is also a complementary alternating magnetic field that is induced. This signature can be used to identify the ship type.



The only way to reduce the CRM signature is to reduce the UEP/ELFE signature, i.e. the galvanic corrosion. This can be done passively and actively. Passive methods include use of anti-corrosion paints, a well-chosen material selection, electrically isolated propellers and sacrificial anodes. Active methods use active systems such as active cathodic protection systems, DeAmp system, and passive or active shaft grounding. Passive or active shaft grounding will reduce the ELFE signature. The shaft grounding system provides a low-resistance path for the current to bypass the shaft bearing. Passive shaft bearings use brushes to ground the shaft to the hull. These devices must be persistently maintained due to rapid deterioration to avoid allowing the ELFE signature to increase. Active shaft grounding systems use electronics to ground the shaft at times when the bearing resistance is high. These will ensure a long-term reduction in signatures.

Figure 6.7-3. Example of Magnetic Signature2 6.7.5 Optical Signature To minimize optical signature, the ship is camouflaged to match its background. The ship’s side should be painted to match the sky and the deck to match the sea. However, the ship almost always has the sea as a background, even when looking from the side since the ship is not always in line with the horizon. It is an advantage to paint the ship in an irregular pattern in order to avoid a symmetric look, which seldom occurs in nature. This is especially suitable for ships whose main purpose is to work in an archipelago or close to a coastline. In dark conditions (night, dawn, etc.), the white water from the bow wake and waterjet flow significantly contributes to the optical signature. The white water can be reduced somewhat by design, although it can also be reduced tactically since at low speed the white water effect is minimized. 6.7.6 Wake Signature Wake management has become important because wake can now be detected by radar and because some modern torpedoes employ wake homing sensors. When the ship moves through the water, it will leave a wake. The wake signature that is generated contains different types of perturbations velocity, pressure and temperature fluctuations, bubbles, surface and internal waves. To handle this signature, it is of importance that the hull, propulsion, hull appendages and rudder are considered as well as the speed, which is a tactical issue. Hull appendages play an active part in the spreading of the wake field, but simulations have shown that the strongest vortices are generated at the bilge and the propeller slipstream. When they interact with each other, they dominate

2 From Davis Engineering, Ltd.



the wake flow field because of the difference in the distribution of energies. The propeller stream contributes to a turbulent kinetic energy. Since tests have shown that the mean kinetic energy is the same for a propelled and an unpropelled hull, the increased turbulent kinetic energy represents a higher percentage of energy in the flow. The surface waves, among other components in the wake, also contribute to the RCS signature since the Vee shaped stern wake is formed behind the ship. Wake should, therefore, be addressed for a variety of signature considerations. Wake signature is very much a tactical issue, since lower speed reduces the wake. It is also a tactical issue since modern torpedoes use the wake to find the ship. An incoming torpedo in the wake can also be hard to detect since the turbulence in the wake also generates noise. 6.7.7 Electromagnetic Emissions/ Electromagnetic Compatibility The electromagnetic signature of a ship should be reduced as much as possible in order to avoid detection by other platforms equipped with receivers to detect the electromagnetic emissions. In order to minimize the emission levels, the ship design should contain a program for achieving EMC (Electro Magnetic Compatibility). Attention should be paid to the transmission of spurious noise from transmitters in non-transmit modes. Electromagnetic Compatibility (EMC) means that the ship with all installed systems, subsystems and equipment must be able to work together in a common electromagnetic environment without any degradation of the characteristics due to Electromagnetic Interference (EMI). In order to achieve EMC, certain rules and requirements must be followed. To be able to enforce EMC, it is of great importance that the ship is contracted with overall EMC requirements. These requirements then have to be translated to system requirements on EMC and instructions for installation, cabling and grounding principles. This means that the ship is identified as a total system that should meet the overall EMC requirements. By applying these EMC requirements to the ship, the electromagnetic emissions are minimized and an acceptable environment for the ship’s sensors and antennas is created. These total system requirements can be raised from the attached generic EMC specification. These requirements concern not only EMI, but also lightning, EMP, Tempest, and HPM, as applicable. These system requirements have to be transformed to suitable equipment requirements for all systems and subsystems that are installed on the ship, ensuring that the overall system requirements will be met. The main contractor, for example the shipyard, should raise detailed equipment requirements to all of the subcontractors as well as for GFE. The main contractor (the shipyard) should appoint an overall EMC Coordinator who is part of the project management team. The EMC Coordinator is responsible for all EMC and related activities, and works in close connection with EMC Coordinators for all contractors and subcontractors involved in the project, including the GFE contractors. This work, management and procedures are described in an “EMC Working Plan”. 6.7.8 Pressure Signature There has been some research in the area of pressure signatures, although it seems that it is not often taken into account when finally building the ship. The hydrodynamic and seakeeping performance is often of more interest than the pressure signature. The pressure signature is dependent mainly on displacement and speed of the ship, and is inversely dependent on length and water depth. The displacement is a function of the mission and size of the ship and is, therefore, hard to change. Increasing the length of the ship can reduce the signature, and, therefore, a long slender ship is preferred over a short wide ship. The most efficient way to reduce the pressure signature is to reduce speed, since in shallow water the pressure is proportional to the speed raised to the fourth power. Therefore, the pressure signature is often a tactical issue, rather than a design issue.



6.8 Small Surface Combatant Ship Vulnerability Reduction Measures 6.8.1 Vulnerability Reduction Objectives Vulnerability reduction (VR) is a classical objective of naval architecture. The methods and the investments vary with the threats and the assessment what is effective and reasonable. Due to the high cost of ships - even SLCs – it is desirable to minimize the vulnerability of small ships in case of a severe accident or a hit. Which general objectives shall be reached by VR measures? The most popular answer is: “The ship shall be able to continue floating and moving”, perhaps with the addition: “Damage control activities shall be possible”. However, this is not sufficient for a combatant ship. In an encounter the ship shall continue fighting and/or after an unexpected attack the ship shall be able to rapid reaction even in case of a hit. VR measures must be effective at once and without personnel. So they must be “built in”. A reasonable set of VR measures for ships of frigate size may comprise:

- excellent damage stability, if possible a 3-4 compartment status - shock protection of all combat relevant systems - limitation of the damage area in longitudinal direction by strengthened/double-plated bulkheads - excellent residual global strength to prevent the hull structure from breaking or collapsing. This is

possible by the incorporation of longitudinal boxgirders or strengthened stringers in the upper deck and a robust double bottom structure.

- high probability of survival of the electric power supply by separating generators by a distance of more than the damage diameter of the specified “design threat” for the ship Due to the dominant importance of the electric power supply for all devices, components and systems on board, the feeding for all relevant switchboards and major consumers has to be redundant and the main longitudinal power supply cables shall be blast and fragment protected. Short circuits in one of the feeder lines shall not disrupt the redundant power supply. With respect e.g. to continuation of missile guidance or the time delay for restarting a major radar some critical parts of the combat system must be provided with un- interrupted power supply.

- chilled water supply for components of the combat systems is nearly as critical as the electric power supply. Therefore the chilled water plants shall be well separated and the piping systems shall be automatically checked due to leakages and automatically reconfigured.

- HVAC (heating, ventilation, air-conditioning) system shall be designed with respect to zones or at best to a level of compartment autonomy to suffer loss of HVAC only in the damage area

- elements of the combat system (sensors, command facilities, weapons) shall be distributed over the ship’s length and combined in such a way that a major hit or a severe accident will not destroy all functions

- accommodation areas for the various ranks shall be distributed over the ship length in such a way that a major accident or hit will not attack too much members of a rank

These measures have been incorporated in the German frigates of the F123 and F124 class. Table 6.8-1 identifies vulnerability reduction methods that are practical for small ships. To get a first idea of the blast damage radii of a hit from a weapon with high explosives and of the reduction of fragment densities by structures Appendix 9.15 can be used. Appendix 9.16 addresses hull girder reinforcement.

A well balanced VR concept for frigates will have similar damage radii for blast, fragments and shock This will be reached by varying the methods of structural protection against blast (noting that parts of the deck or the shell shall be rapidly destroyed by the blast allowing for a massive venting of the compartment to avoid a significant quasi-static overpressure which would be very dangerous for the structure) and the protection measures against fragments and adapting the shock protection devices for a proper shock level.



The goal of VR measures is not the survival of single components. Instead the survival of functional chains is necessary. An example of a functional chain is the combination of sensor-command facility-weapon, plus the necessary supply of all vital services, i.e. electric power, chilled water, etc. Even an intact CIC does not have operational value, if this CIC does not get information from the sensors and the communication systems, it is not able to generate and distribute commands and cannot execute weapon launches. Even an intact weapon is useless without electric power supply and the ability to get and react on commands. So it is of utmost importance for a low vulnerability of the ship to define all functional chains with all of their elements and arrange the elements of each functional chain in such a way that the longitudinal extension of the chain is minimized to create a minimal “ hit-silhouette”. Redundant functional chains should be separated as much as possible in the ship’s longitudinal direction to avoid a loss of both chains by one severe hit or accident.

Unavoidable combat relevant cabling, piping or ducting which extends over a major part of the ship’s length has to be protected and redundant. It is the German point of view that fragment protection also shall be as effective as blast protection. Germany therefore prefers the high tensile shipbuilding steel and reinforced hull girders. But fragment protection is relatively heavy. As an example: If you assume minimal fragment protection for the bridge of a small combatant, and if you want to be able to continue maneuvering of a ship and rapid reaction to the attack you have to protect the:

• bridge • sensor • weapon with ammunition • CIC • comms room • electric power supply • chilled water supply • propulsion system

This means the protection of about 250 m2 of surface area. An additional 4 mm plating with about 80 mm stiffeners means about 10 tons of additional weight. Composites may be able to reduce the weight of protection. In addition, the design of bulkheads should be A60 (or more) fireproof. To be fragment, blast-and shockproof the fire insulation should be incorporated in double-plated bulkheads. It is also necessary to be aware of losses of damage control material, medical facilities and supplies and lifeboats/ inflatable life rafts in case of a major accident or hit. Therefore, it is necessary to increase the quantities of these materials significantly and distribute them well over the ship’s length. SLCs are much smaller than the German Type 123 and 124 class frigates, on which the vulnerability reduction discussion has so far been based. The shallower hull depth, narrower beam and shorter length of SLCs have a major impact on overall hull girder strength and the thickness, and therefore the toughness, of basic hull structure. Moreover, high speed is often a vital operational requirement for SLCs. This tends to result in a necessity for a relatively lightweight hull. Past design studies have shown that within the limits of small ship displacements considered herein (600 to 2000 tonnes) global hull girder section modulus requirements do not generally determine the midship section scantlings. Rather the relatively thin stiffened plates required to meet local loads will also generally provide adequate hull girder strength. Therefore main deck and side shell plating will often be only 5 to 7 mm. Given the inherent constraints applicable to SLCs, the vulnerability reduction considerations for SLCs cannot follow frigate practice. Moreover SLCs are often more likely to be engaged by small craft, terrorists or shore defenses and therefore have to consider ballistic protection against very different threats than larger combatants. Defeating small caliber (7.62 to 23 mm) projectiles and/or terrorist rocket propelled grenades can be relatively more demanding than providing enhanced fragment protection, or even constraining the damage caused by larger warheads. Appendix 9.16 indicates that 5mm bulkhead



panels will be destroyed or severely damages by blast up to a distance from the point of detonation equal to:

D=1.9*(He)1/3 Where for a typical high explosive weapon reportedly

He= 0.75 Wt x 1.15, or 0.8625 Wt Typically: For shells, Wt.content/Wt.warhead < 0.30. For bombs, Wt.content/Wt.warhead < 0.50. A deck or side shell panel will typically be larger than a bulkhead panel. Therefore the above noted equation should be conservative when applied to 5mm hull panels. Thus, let us assume that the detonation standoff distance will be less than 0.75 of the average hull depth, then:

He Required SLC for Destruction/ Required Displacement Dmax Severe Damage Weapon 600 t 4.5m 15.64 52 kg shell 2000 t 6.4m 38.22 89 kg warhead

These are relatively small weapons. For 600-2000 tonne SLCs passive protection against most large weapons is not feasible. Hit avoidance is the only practical option versus large weapons, and causality minimization, vi ce ship survival should be the primary design objective once hit. Conversely SLC design might still address less catastrophic threats. These include:

• Ballistic protection against small caliber weapons and/or terrorist threats, • Shock protection against mines and near miss weapons, • NBC attack

The prioritization and resources allocated to these threats will depend on mission requirements. Ballistic protection trade off studies were studied for a 2000-tonne SLC, as previously presented in Sections 3.4.5.1 and 3.4.5.2 respectively. The impact of shock protection was studied for the 2000-tonne OPC in Section 3.4.3.1.



Table 6.8-1 Vulnerability Reduction Measures versus Ship Size and Threat Type of ships

Ship Size 600-Tonne, Littoral Combatant 1700-2000-Tonne Littoral Combatant, OPV Measures 1 3 4 5 6 8 9 10 11 12 13 1 3 4 5 6 9 10 12 13

Threats

Surface:

Hand weapons

X X X X X X

Artillery/small ASM

X X X X X X X X X X X X X X

Middle ASM O O O O O X X X X X X X Heavy ASM O O O O O O O O O O O O

Subsurface: Stand-off hit

of a mine X X

NBC:

Particles protection

X X

Evaluation: X=effective O=not practical without sign=not relevant ASM – Anti-ship missile Measures: 1: bullet/fragment protection of selected (most important) functional chains (e.g. naval engineering and weapons systems) 3: strengthened bulkheads or double plated bulkheads 4: strengthened stringers 5: compartment-related electrical power supply with a redundant feed 6: separation of (more or less) redundant components of the combat system 9: two separate electric power plant systems 10: distributed HVAC and chilled water system 12: shock protection of the equipment with shock mountings 13: permanent NBC-protection system, washdown/spray systems, air locks 7: double bulkheads 2: covering bulkheads w/kevlar or other material 11: electrical take name drive



6.9 Sea and Air Vehicle Launch and Recovery 6.9.1 Sea Vehicle Launch and Recovery Other types of vehicles to be such as ROVs. A recent worldwide search to identify technologies employed to launch and recover small boats from ships revealed that a number of countries are employing stern ramps as a means to launch and recover small boats. Nine ships of various sizes were identified for investigation to determine the effectiveness of their deployment systems. In addition, the ship’s designers were contacted in an effort to determine the design criteria they had employed during the design. The following ships were identified:

a. Japanese Coast Guard Cutter, Erimo in Tokyo, Japan b. Mexican Navy Ship, Justo Sierra in Acapulco, Mexico c. U.S. Navy Patrol Craft, Tornado in Little Creek, Virginia d. Canadian Coast Guard Ship, Gordon Reid in Victoria, British Columbia, Canada e. Netherlands Antilles and Aruba Coast Guard Patrol Craft, Jaguar in Curaçao, Netherlands

Antilles f. Finnish Frontier Guard Ship, Telkk ä in Turku, Finland g. USCG Coastal Patrol Boat, Hammerhead in Baltimore, Maryland h. German Sea Rescue Service, Vormann Steffens in Bremerhaven, Germany i. Swedish Coast Guard Ship, KBV 201 in Karlskrona, Sweden

Visits to ships, ship owners, and designers were performed to establish the operating characteristics of the stern launching/recovery systems. The main areas of their design and operation that were investigated are as follows:

a. Size of ship b. Type and size of small boat c. Types of systems d. Ramp design considerations e. Equipment f. Launch and recovery operations g. Time intervals for launch and recovery h. Design and operational sea states i. Manning requirements j. Training

6.9.2 Size of Ship Tables 6.9-1, 6.9-2 and 6.9-3 summarize the mother ship characteristics, the small boats, and the operating characteristics of the deployment systems. The ships ranged in size from 26.5 meters for the U.S. Coast Guard’s Coastal Patrol Boat, Hammerhead, to 92 meters for the Japanese Coast Guard’s ship, Erimo. The length of the ship affects the motions and accelerations at the stern. The longer the ship, the higher the accelerations and the greater the motions, limiting use in higher sea states.



6.9.3 Type and Size of Small Boat All vessels visited used Fast Response Craft (FRC) for deployment from the stern. The majority of the FRCs were of the Rigid Hull Inflatable Boat (RHIB) type. Three ships, the Erimo, Justo Sierra, and Vormann Steffens, used small boats other than the RHIB. The Erimo’s FRC was made of fiberglass with an operator’s cockpit located amidships. The Justo Sierra’s FRC was an aluminum-hulled Interceptor with an operator’s cabin and seats for a boarding party of four. The Vormann Steffens’ small boat was self-contained and self-righting. The majority of the small boats carried were between 7 and 7½ meters long. The largest boats carried were 11 meters long and the smallest was 5.5 meters long.

In addition to the stern-launched small boats, four of the largest vessels, Erimo, Justo Sierra, Gordon Reid, and Jaguar, also maintained the capability of launching small boats over the side. The small boats for over-the-side launching on the Gordon Reid and Jaguar were for emergency use only. On the Erimo and Justo Sierra, the side -launched boats were in addition to their stern-launched boats. While the Japanese preferred to use their side -launched boat for normal boat operations, the Mexicans preferred to use their stern-launched boat. 6.9.4 Types of Systems The stern deployment systems can be separated into two types, as summarized in Table 6.9 -1. The first type is a well dock, as exhibited on the Japanese Coast Guard ship, Erimo. In this type of deployment, a stern well is flooded and the small boat is floated and powers its way out of the ship. The second type is a ramp, either fixed or hinged. The second type is more widely used. The ram ps can be either shaped to fit the hull of the FRC or flat with longitudinal runners that support the FRC’s hull. Both types of ramps use a friction-reducing material, such as Ultra-Poly or Teflon. Two ships used rollers and wheels to reduce friction. These provide a low-friction surface that permits the FRC to slide or roll down the ramp easily. One of the ships, Gordon Reid, has a ramp that is hinged and can quickly raise the FRC to deck level, removing the boat completely from the water.

Table 6.9-1

Ship and Ramp Characteristics

Ship Length of Ship

Type of Stern Ramp

Slope of Ramp

Erimo 92m Well Dock None Justo Sierra 74m Fixed Ramp 8¼° Tornado 55m Fixed Ramp 16° - 18° Gordon Reid 50m Hinged Ramp 15° Jaguar 43m Fixed Ramp 14° Telkkä 49m Fixed Ramp 7° Hammerhead 26.5m Fixed Ramp 13° Vormann Steffens 27.5m Fixed Ramp 14° KBV 201 52m Fixed Ramp 12°

6.9.5 Ramp Design Considerations The ramps can be categorized as two different types. The first type is a flat ramp that uses tubular bunks to support the RHIB. The second type of ramp is a shaped ramp where the ramp surface is built to suit the shape of the FRC and lined with friction-reducing materials. The slope of the ramps varied between 7° on the Telkkä to 18° on the Tornado. The Finnish Frontier Guard ship, Telkkä, used a cradle on rollers to deploy and recover the FRC. The wheeled cradle of the Telkkä permitted launching the FRC with the low 7° ramp angle. The cradle, in the deployed position, became a ramp extension permitting the lau nch and recovery of the RHIB over a sill that is approximately one foot above the waterline.



The Swedish Coast Guard’s ship, KBV 201, used a ramp that was covered with wheels and rollers to reduce the friction. It also had a stern gate that hinged down to form an extension to the ramp to provide greater sill submergence. The Vormann Steffens also had a transom that was covered with rollers to provide additional sill submergence. The ship also had a self-capture mechanism that would attach the small boat to a chain-driven recovery mechanism. This mechanism permitted the hook-up of the boat during recovery without assistance from a deck hand. The 8¼ ° slope of the Justo Sierra’s ramp was too low to permit the FRC to overcome its own static friction and self launch. Capstans located on each side of the ramp were employed to initiate sliding for launch. The low angle of the ramp was necessary to obtain the necessary vertical clearance over the flight deck needed to house the FRC. All ships with ramp slopes of 12° and higher were capable of launching the FRC without assistance. The use of friction-reducing materials, such as Ultra Poly or Teflon, wheels and rollers were used on the sliding surface of all ramps except the Telkk ä, which used the wheeled cradle. The stern ramp on the Gordon Reid is hinged. During launch and recovery operations, the ramp is hinged down 15°. When not performing launching or recovering operations, the ramp is brought up to the deck level providing easier access to the FRC and removing it from the water for storage and/or maintenance. The ramp surface is constructed of grating. The surface of the grating acts to dampen the wave motions in the ramp making launch and retrieval easier. At the bottom end of the ramp, there is a pad of friction -reducing material to keep the bow of the FRC from coming in contact with the grating during launch and recovery. Ramp width is determined by adding a suitable clearance between the FRC and the side bulkheads of the ramp. The clearance must be sufficient to give the coxswain confidence when entering the ramp, but not so much that the FRC will come to rest out of position. The clearances observed on the ships visited varied widely from as small as 10 cm to as much as 50 cm. During recovery, the FRCs were observed fending off the entrance corners of the ramps. To prevent damage to the boat collars, the entrance corners to the ramp should be rounded and smooth. The use of square or sharp corners can cause damage to the boats. The ramp openings are closed either by doors that hinge outward or by gates that hinge up or down. With outward hinging doors, they can be used to form a “funnel” to help the coxswain guide the FRC into the ramp. The gates that hinge upward must be designed so that there is sufficient overhead clearance between the boat crew and the gate for the worst sea conditions the ship is expected to encounter. The coxswains of FRCs that enter ramps with gates noted that they feel they could hit the open gate if the pitch gets too great. Downward hinging gates were observed on ships that must operate in icy waters. In the deployed position, they provide the sill depth that is needed to recover the FRC. The sill depth was the biggest factor governing available recovery time. The ships investigated had sill depths that varied from 30 cm above to 86 cm below the design waterline. The Telkk ä is an ice strengthened ship and was designed with a ramp sill that is approximately 30 cm above the waterline to prevent ice from entering the ramp area during backing operations. On the ships with downward hinging stern gates, the end of the ramp at the transom is at, or near, the waterline. The Gordon Reid has a sill depth of 86 cm and is the only ship that can routinely perform stern ramp deployment operations in sea states of five and greater. All other ships were limited to sea states between two and four. In the case of the Erimo, the actual maximum operating sea state (two) is considerably less than the design (four). The greater sill depths generally translate into the ability to operate in higher sea states. 6.9.6 Equipment The FRCs or small boats observed on the ships investigated fell into two categories, RHIBs and others. Table 6.9-2 summarizes the characteristics of the boats used. The majority of the small boats were RHIBs between 7 meters and 7½ meters long. Only three ships used non -RHIBs, the Justo



Sierra, which used an 11-meter aluminum -hulled Interceptor, and the Erimo and Vormann Steffens, which used a fiberglass fast response craft. Power was provided by diesel engines in all but one vessel, the Gordon Reid, which used gasoline-powered outboards. The outboard-powered RHIB is very responsive to throttle and very maneuverable. All the diesel-powered small boats used waterjet propulsion with the exception of the Navy’s 7 -meter RHIB, which used an I/O drive, and the Vormann Steffens, which uses an inboard with a skeg that protects the propeller. The larger 11-meter boats used twin waterjets for propulsion. The advantage of the waterjets is that there is no appendage that hangs below the hull to interfere with launch and recovery operations. However, the directional stability of waterjets in the stern wake is limited, and all but the most experienced coxswains had difficulty transiting the wake. With I/O drives and outboards, there is better directional stability in the ship’s wake, but the lower units can interfere with the ramp. On the Tornado, the lower unit is raised before the RHIB is winched completely up the ramp. On the Gordon Reid, the hinged portion of the ramp ends before the lower units of the outboards, preventing any interference.

Table 6.9-2

Ship and Boat Characteristics

Ship Size of Small Boat Boat Type Propulsion

Erimo 5.5 m Fiberglass FRC Waterjet Justo Sierra 11 m Aluminum FRC Waterjet Tornado 7 m & 11 m RHIB I/O & Waterjet Gordon Reid 7.33 m RHIB Outboard Jaguar 7 m RHIB Waterjet Telkkä 7.4 m RHIB Waterjet Hammerhead 7 m RHIB Waterjet Vormann Steffens 7.5 m Fiberglass FRC Inboard KBV 201 7.65 m RHIB Waterjet

One nice feature of the RHIBs used on the Gordon Reid and the Jaguar is an inflatable collar that wraps completely around the stern. The additional collar segment provides flotation for the RHIB’s stern, preventing submerging the stern during launch and recovery. On the Gordon Reid, it also prevents submerging the engines and ingesting water into the carburetors during launch and recovery.

The mechanical equipment used on the ships for the operation of the stern doors, winch, and hinged ramp is generally all powered by hydraulics. In a few cases, the retrieval winch is electric. Hydraulic cylinders are used on all the stern doors and gates. Power for the hydraulics is supplied by either a dedicated hydraulic power unit or as part of the ship’s hydraulic system.

6.9.7 Launch and Recovery Operations

All the ships responded that they could launch the small boat in any sea condition that the small boat could safely handle, but that recovery was limited by the sea state. The majority of the ships preferred launching with the ship’s course set directly into the waves (0°). As an alternative, they would fall off the wave by up to 30° to reduce the pitching motion. The Finnish ship, Telkk ä, and the Swedish ship, KBV 201, preferred to run with the waves at the same speed as the waves. This gave them the optimum condition for deploying their cradle and RHIB. The Canadian Coast Guard ship, Gordon Reid, preferred to run parallel to the waves (heading of 90° relative to the waves) when performing boat operations in high sea states. The Gordon Reid found it easier to launch and retrieve the RHIB with rolling motions as opposed to pitching motions. Model tests performed for the ship verified that boat operations could be performed in higher sea states when operating in beam seas. Table 6.9-3 summarizes the launch characteristics of the ships investigated.

Table 6.9-3

Launch Characteristics

Ship Launch Heading

Ship Speed Launch Time



Erimo 0° 4-7 kts 15 sec Justo Sierra 0° 1-3 kts 20 sec Tornado 0° 5 kts 18 sec Gordon Reid 90° 5-6 kts 10 sec Jaguar 0° 5-8 kts 8 sec Telkkä 180° 6 kts 35 sec Hammerhead 20° 3-5 kts 7 sec Vormann Steffens 0° 5 kts 6 sec KBV 201 180° 5-8 kts 10sec

Table 6.9-4 summarizes the recovery characteristics of the ships investigated.

Table 6.9-4

Recovery Characteristics

Ship Recovery Heading

Ship Speed

Recovery Time

Erimo 0° <4 kts 10-15 sec Justo Sierra 0° 0 kts 15-20 sec Tornado 0° 5 kts 12-20 sec Gordon Reid 90° 5-6 kts 8-18 sec Jaguar 0° 6-10 kts 10-14 sec Telkk ä 180° 6 kts 12-15 sec Hammerhead 20° 3-5 kts 9-12 sec Vormann Steffens 0° 5 kts 10-15 sec KBV 201 180° 5-8 kts 10-12 sec

The ship speed for most launchings was between 3 and 6 knots. This gives the mother ship enough forward motion to maintain her course, but is still slow enough for the RHIB to escape the stern wake after launch. Launching times varied directly with the launching procedure. The launching time is defined as the time from when the command to launch is given until the boat is clear of the transom. The quickest launches (7 seconds) were experienced on those ships where the diesel engines are started dry. On these ships, after the stern gates are opened, all that is involved in the launch is to pull the quick release mechanism. Adding a winch to lower the boat into the water before starting the engines increased the launch time to about 10-15 seconds. When the cradle or assistance was needed to launch the boat, as was the case for the Telkkä or the Justo Sierra, the launch time approached 35 seconds. During recovery, the majority of the ships preferred the same course as they did for launch, head seas to 30° off the waves. The exceptions are the Gordon Reid, the Telkkä and the KBV 201. The reasons they prefer their recovery directions are the same as for launch. The mother ship speed for recovery is nearly the same as for launch. However, Jaguar’s recovery speed is doubled to nearly 10 knots, or twice that of other ships. At the higher recovery speed, the waterjet-driven RHIB must travel at a higher speed where it has better directional stability, necessary during the recovery operations. The recovery times are typically quicker than launch times. The recovery time is defined as the time it takes from when the coxswain decides to enter the ramp until the RHIB grounds on the ramp. At this point, the RHIB is attached to the winch and hauled up to the storage position. The recovery times were found to be nearly constant at 10 to 12 seconds.

6.9.8 Design and Operational Sea States The sea state limit on operating is dependent on the ramp design and the coxswain’s ability. The Canadian Coast Guard ship, Gordon Reid, was designed with the capability to perform boat operations in sea state 6. Model tests were carried out in the Straight of Juan de Fuca near Victoria, British Columbia where this was verified. The Gordon Reid has been operating for about ten years. During the early years, the crew’s lack of experience limited recovery operations to sea state 3. In the



years since, they have become proficient at operating in sea state 6, with an occasional sea state 7 recovery. The design of the Gordon Reid uses four design features that permit operation in the higher sea states. The first is a very deep sill submergence (86 cm at the design waterline). With this depth, the sill is submerged throughout the full range of ship’s motions under all operating conditions. The second design feature is the hinged ramp. This allows the crew to enter and exit the boat from the deck on the level. It also removes the RHIB from the water quickly. Without it, the seas in the ramp would pound the stern of the RHIB until the stern doors closed. The third design factor is the clearance between the RHIB and the side bulkheads of the ramp. On the Gordon Reid, there is a clearance of 33 cm on each side of the RHIB. This gives the coxswain a target with some forgiveness for an off-center recovery. Finally, the intersection of the stern and the ramp bulkhead is generously radiused, providing a smooth entry to the ramp well. This prevents damage to the RHIB collar during recovery operations.

Table 6.9-5 shows a summary of the design and operational sea states. It is to be noted that, for several deployment systems, the maximum operating sea state is less than the design sea state.

Table 6.9-5

Ship and Boat Operating Characteristics

Ship Sill Depth

Design Sea State

Operating Sea State

Erimo NA 4 3 Justo Sierra 0 cm 3 3 Tornado 38 cm 3 3 Gordon Reid 86 cm 5-6 6 Jaguar 30 cm 4 4 Telkkä -30 cm 3 2 Hammerhead 35 cm 4 4 Vormann Steffens 60 cm 1 1 KBV 201 30 cm 4 4

* Sill on the Telkkä is 30cm above the waterline

6.9.9 Manning Requirements

In most cases, launch can be performed by as few as three people, a coxswain and a bowman in the boat and a winch/door operator on the deck.

Recovery operations can be performed with as few as three people performing the same functions as they do during launch.

One ship only required two people to perform the launch and recovery operations. This was the KBV 201. During launch, the coxswain used a remote release lanyard to release the winch hook. During recovery, the winch operator attached the winch line to the FRC by using a long pole to hook an eye to the FRC’s bow. After hook -up, the FRC was winched up the ramp.

There were, however, some ships that required higher manning levels. The Justo Sierra required a minimum of seven people to launch (officer-in-charge, two capstan operators, two fender holders, hydraulics operator, and one person to untie the bow). For recovery, a minimum of seven people were required (officer-in-charge, two fender holders, one to attach winch line, one to hold tether for winch line, one to operate the winch, and one to operate the hydraulics). When we visited the ship, there were many others present on the ramp deck who participated in training. Two people were all that was needed in the small boat.

On the Tornado, three deck hands were needed to recover the small boat (two to pass the winch line to the boat and one to operate the winch). They only needed one on deck to launch. Two people in the boat were needed to launch and recover.



6.9.10 Stern Wake Influence on Recovery

The wake of the mother ship is a hydrodynamic problem that has not been num erically analyzed due to the complexity of its nature. The factors that influence the wake are the ship’s hull form and the propeller wash. They combine to form turbulent eddies that make slow-speed transit of the wake difficult. The effects of the wake are presently best understood through empirical observations. All the ships, except the Tornado, had two propellers. During launch and recovery operations, it was observed that the wake would form a depression between the two propeller washes. This trough would aid in centering the RHIB during recovery operations. On the Tornado, which has four propellers, recovery operations were performed with the two inboard shafts declutched to reduce the propeller wash aft of the ramp. All the small boats exhibited difficulty navigating the wake and keeping the boat on a straight-in approach. The stern wake made it difficult to maintain directional control of the small boat. As the sea states increased, the wake effects worsened. The natural tendency of the coxswains is to over steer when making the approach to the ramp. In all sea states, except flat water, a last minute correction was observed as the RHIB traversed the stern wake and entered the ramp. The slow-speed directional control of the RHIB when equipped with waterjets is minimal, making transit of the wake difficult. The approach speed of the RHIB is approximately twice the speed of the mother ship. On the Jaguar, to maintain better directional control of the RHIB, the recovery speed is increased to between 6 and 10 knots. This permits RHIB recovery speeds of between 12 and 20 knots, providing better directional control during recovery. On the Gordon Reid, the RHIB is equipped with outboard propulsion, and it exhibited better directional control at the recovery speeds than did the waterjet-propelled boats. All stern deployment systems observed are located on the ship’s centerline. The recovery course of the RHIB is centered between the more turbulent parts of the wake produced by the propellers. In this position, the coxswain can maintain better maneuverability and directional control of the RHIB, increasing the likelihood of a successful recovery. 6.9.11 Conclusion The German Sea Rescue Service (DGzRS) has been using stern-launched daughter boats the longest of any organization visited. They have been developing their stern launching technique since 1953. However, the DGzRS recovery is limited to the lowest sea state of all. The newest ship belongs to the Swedish Coast Guard. Their recovery system utilizes rollers and wheels on the ramp surface. Continual testing is being performed to find the optimum combination of wheel arrangement, material and support. The search and rescue mission requires the capability to perform small boat operations in conditions up to sea state 5. Only one ship, CCGS Gordon Reid, was capable of recovery operations in sea states of 5 and higher. Gordon Reid has been operating for over ten years, and the crew has developed great skills in launch and recovery operations. The ship was designed with features to facilitate operations in higher sea states. The 86 cm of sill submergence, the largest of all ships investigated, permitted operation in high sea states without sill emergence. The RHIB was supported by longitudinal rails on an expanded metal ramp with side clearance between the boat and the ramp walls of approximately 30 cm. This arrangement aided the flow of water out of the ramp area. This was the only ship found to have a hinged ramp with which the RHIB could be raised up out of the water and up to deck level. The boat winch was high speed, operating at 1 m/sec, and was capable of pulling the RHIB to the stowed position very quickly. Finally, the entrance to the ramp was well rounded, allowing the coxswain to fend off the ramp corners during recovery. 6.9.12 Other Boat Launch and Recovery Systems



In addition to the stern launch and recovery systems previously discussed, small ships of the size being studied also make use of davits to launch and recover boats. There are seven distinct types of davits available today. They are: Overhead Suspended Davits Pivoting Davits Pivoted Link Davits Pivoted Sheath Screw Davits Radial Davits Slewing Davits Trackway Davits There are a number of different configurations of each of the davit types discussed above.

6.9.13 Aircraft Launch and Recovery Systems

Many of the missions of OPVs and SLCs today necessitate that medium and heavyweight helicopters be integrated with these small ships to perform in advanced sea conditions. In addition, there is growing interest in being able to launch and recover unmanned aerial vehicles from these types of ships. The biggest challenges for recovering aircraft on small ships is providing the pilot with accurate and current guidance on when it is safe to land on the deck of the ship during periods of reduced visibility, high seas and at night, and securing and handling the aircraft once it is on the deck. The problem with small ships is that as ship displacement decreases, ship motions increase, which elevates the need for operational guidance and places greater demand on the securing and handling equipment. Additionally, because the size of the crews of the ships being studied is limited, manual securing and trave rsing of the helicopter places a great burden on the crew. Today, work is ongoing to optimize a number of systems to extend the range of helicopter operations and make them safer. These systems include approach and landing guidance systems, securing systems, and combination securing and traversing systems. The approach and landing guidance systems and securing systems offer great promise in improving the helicopter launch and recovery capabilities of small ships. 6.9.13.1 Approach and Landing Guidance Systems There are a number of approach and landing guidance systems available, or currently being developed, to extend the ability to recover aircraft on small ships at night, during periods of reduced visibility, and in high sea states. All of these systems rely on lights to provide the pilots guidance to approach and land the aircraft on the ship. The information that the light systems provide varies significantly from system to system and can be as simple as providing spatial definition of the flight deck and its surroundings, to more complex systems that provide a steady reference to the horizon as the ship rolls, to very computationally demanding systems that measure ship attitude and motion along with real-time sea wave characteristics to determine the shortest time period before which the ship will exceed helicopter landing parameters. 6.9.13.2 Securing Systems The systems used for securing helicopters onboard small ships fall into two categories based on the securing principle used:

a) Passive securing systems: those in which a structural member fitted to the helicopter and fixed to the ship reacts to the helicopter loads, restraining it from movement and transferring the loads into the ship’s structure. Securing is limited only by the strength of the securing element(s) and the supporting structure.

b) Active securing systems: those in which forces are continuously applied to the helicopter by an active, helicopter-mounted, securing device in an effort to increase landing gear vertical reactions enough to create sufficient landing gear frictional reactions to prevent sliding. Securing is limited



by the magnitude of the force, the landing gear capacity, the tire deflection limits, and the deck coefficient of friction.3

6.10 Manning/Human Factors/Automation/Maintenance Philosophy 6.10.1 Introduction Manning has become a major design issue. Different navy’s often have different opinions regarding manning. The reason for this paper is to explain the different aspects of management concepts, both theory and practise.

This paper gives an overview of the present theory and the application of this theory. Also, an “allied naval engineering publication” (ANEP) according to manning exists, ANEP 21. This paper is not a replacement of this ANEP 21.

”Management concepts” are divided in “ship management concepts” and “fleet management concepts”. Ship management concepts deal with the management aspects of a single ship and fleet management concepts deal with the management aspects of a complete fleet or class of shi ps. Manning problems, and in particular the task allocation and subsequently crew list design, are part of a management concept.

It is obvious that the development of management concepts is a very complex process. For example, during the design of a crew list all the aspects of manning must be considered, like personnel, materiel and procedures as well as their interrelations. It will be clear that this process of crew list development must be executed during the (pre)design phase of a vessel. Only then optimization of the above manning problem is obtained. Management is the answer as to how the ship’s crew is able to achieve operational objectives, using machinery, software and other relevant equipment. Despite the human being’s important role in management, the design process doesn’t always start with the development of the crew list. Management brings man, machine and software together at one equal level and allows the different tasks to be optimally shared between them.

The conclusion after many researc hes is that the principles of developing new management concepts and optimizing manning problems, are independent of the ship size. Only differences in the missions (and therefore in ambition level) lead to differences in management concepts. However, in general a small ship is manned by a smaller crew. On board of a small ship still many specialists are needed, which conflicts with a small crew. Therefore the challenge in designing small crews is to find adequate solutions for allocating these specialists tasks.

Ship management concepts and manning problems as part thereof are based on ambition level and costs (both initial and life cycle). The ambition level describes which ship functions can be realized to which level (for instance a performance requirement for damage control) and which ship functions can be performed simultaneously (for instance can damage control and AAW be performed simultaneously).

In the first chapter this paper will describe the theory of manning problems, in the second chapter this theory is applied at one example. The purpose of this example is to show the influence of the type of mission(s) at the crew list design. In the third chapter, some trends in crew reduction measures and present and future researches are describe d.

3 From “A New Approach for Passive Securing at Landing and Powered Handling of Helicopters Onboard Small Ships” A. R. Tadros, et al, Warship 98 Conference

Figure 6.10-1. Personnel in Ship Control Centre (SCC), Controlling and monitoring platform systems



6.10.2 Manning theory 6.10.2.1 Mission versus budget Every ship design starts with an analysis of intended missions, which consist of mission tasks and required capabilities. Ambition for, amongst others, sustainability, survivability and simultaneity can also be derived from the missions. Capabilities and derived needs will be filled in with functions performed by human, machine or a combination of the two interrelated by procedures. Human functions can be divided into tasks with a certain work - and time load. This forms the basis of the manning problem. The key to crew reduction is therefore the adjustment (lowering) of the ambition concerning missions, mission tasks and capabilities.

SCENARIOANALYSIS

FUNCTIONALDECOMPOSITION

TASKANALYSIS

HUMAN

TASKALLOCATION

TASKANALYSISMACHINE

SCENARIOANALYSIS

FUNCTIONALDECOMPOSITION

TASKANALYSIS

HUMAN

TASKALLOCATION

TASKANALYSISMACHINE

Figure 6.10-2. Waterfall principle

Another important factor in manning is of economical nature. A low budget results in low materiel en personnel investment. In most cases this results in a labour intensive ship (large crew) with consequently high in -service costs. These costs decrease the available budget for investment in new building projects: a downward spiral of ambition. Another way to approach this problem is to assume that a low, politically set, ambition level results in less funding for the product. Again the downward spiral appears. Is ambition leading over budget or is budget determining the reachable ambition? We have to disregard this non-relevant chicken-and-egg problem and focus on breaking the downward spiral. This can be done by accounting for personnel in-service costs during the ship design. The crew can be reduced by implementing personnel reduction measures, which can be financed by ‘to-be-saved’ labor costs. As the number of personnel decreases, subsequently a second trade-off is achieved by the downscaling of person nel-support provisions such as accommodation and ‘lodging and care’. This second trade -off saves initial platform costs, which can be invested. This way the downward spiral can be transformed into an upward spiral to a certain extent. The level that can be reached depends on labor costs, state of knowledge and availability of technology and perhaps most important a (political) will to clearly make choices. 6.10.2.2 General principles of manning 6.10.2.2.1. Procedures, materiel and personnel As mentioned in the introduction, two types of management can be defined: ship management concepts deal with the management aspects of a single ship and fleet management concepts deal with the management concepts of a complete fleet or class of ships. This division into ship and fleet management concepts is applied because of the different effect that some of the (reduction) measures have. Some of these (reduction) measures are only effective to a single ship and some of them are



only effective to a complete fleet. In the next paragraphs the measures and factors of influence applied to a single ship (ship management concepts) and those applied to a fleet (fleet management concepts) are discussed. In this paragraph the general aspects of manning, belonging to both ship management concepts and fleet management concepts, are discussed. The three most important aspects for both management concepts are:

• procedures • materiel • personnel

The optimum tuning of these three aspects provides the optimum management concept. The aspects can be seen as input variables, when one aspect is given as a fixed starting point. For example, when a minimum of personnel is required, procedures and materiel must be considered as variables. Defining the optimum mixture of the aspects above is one of the most difficult parts of the management concept design, because of the many opposite interests, for example a minimum budget on one hand and the wish of high tech materiel on the other hand. (see paragraph 6.10.2.1) 6.10.2.2.2. Peak load and workload

Workload is not evenly distributed in time. Some processes create peak loads like mooring and damage control. Other processes determine the basic load like continuous operational tasks and preventive maintenance. At some moments dips in workload occur, often planned like dinner or afternoon -rest. The graph of workload plotted against time is shown in figure 6.10-3.

This graph can be used in two timescales. If the timescale covers a day, week or deployment we consider the workload contribution of single tasks on a single ship as described above. If the timescale covers a year, an operational cycle or even a lifecycle of a ship, the peaks and pits are formed by the several successive missions a single ship goes through.

Crew reduction measures can be tailored to a single ship on the short period, which is considered in ship management concepts. Different reduction measures can be thought of with a class of ships or a fleet in mind for the longer period, which is considered in fleet management concepts. Focus on the reduction of a peak load only is not effective because another peak load dictates the number of crewmembers needed. On the other hand, regarding just average workload is not effective because the highest peak still determines the number of crewmembers needed. Basic principle in both views is therefore that a wide, integral approach is needed to reduce both the average workload and the peak load.

time

# cr

ewm

embe

rs

1. Reduce average work load 2. Reduce peak load

Figure 6.10-3.Peakload and Workload

Figure 6.10-4. Action state generates a high workload and peakload



6.10.2.3 Ship management concepts 6.10.2.3.1 Crew reduction measures As mentioned before, ship management concepts deal with the management aspects of a single ship. For both ship management and fleet management, the aim of reduction measures is to lower the average workload and peak load. Reduction measures for a single ship are: buffering: take measures to allow postponing of (some of) the (peak) workload to a convenient time (move the peaks to the pits) mechanization : mechanize labor work to reduce the number of people working simultaneously or to reduce the time needed for the task. automation: automate tasks to either keep human out of the loop (no workload) or get more tasks done by less people (less workload and operator load). architecture : optimize the global arrangement of the ship, layout of systems and positioning of components to lower workload. outsourcing: shift the workload from the crew to a shore based organization. Average workload originating from maintenance and paper work (administration) can be outsourced relatively easy, but also peak workload, like specific knowledge required for trouble-shooting, can be outsourced (see paragraph 6.10.4.2.3). However outsourcing has its effect on a single ship, more advantage can be taken if outsourcing is approached as an integral concept comprising fleet and shore-organization. 6.10.2.3.2 Efficient and Effective division of personnel 6.10.2.3.2.1 Operational, quick reaction and support process Three processes can be recognized on board: “Operational”, “Quick Reaction” and “Support”. All tasks can be categorized in one of the processes. The operational proces s consists of time critical tasks. This means that the tasks must be performed instantly or continuously and cannot be interrupted. The operational process consists of tasks concerning navigation, picture compilation in the combat information centre or the deployment of weapons (from CIC or locally). The quick-reaction process deals with calamities and therefore consists of tasks like fire-fighting and medical treatment. The support process contains all other tasks like maintenance, personnel care and administration. The support processes are, in the long term, as important for the endurance of the ship as the operational processes. These tasks can be interrupted or to some extent be delayed (re-scheduled) and are thus flexible. During transit and in peacetime with no exercises the “transit”-schedule is used and during war time and exercises the two schedules of “defence stations” and “action stations” are used dependent on the actual treat. During transit only the necessary tasks from the operational and support -processes need 24-hour coverage (i.e. tasks at bridge and SCC). The remainder of the crew only works during daytime in the support-process. A part of the support personnel is member of the quick reaction organization. Because the possibility of a cal amity happening during transit is very low (no battle damage, only civil risk), it is acceptable that response times are somewhat longer and the organization can be smaller. Therefore in transit no people are allocated dedicated and continuously to the quick-reaction process. If necessary, people from the support process interrupt their support tasks and start their quick-reaction duty. In conventional crew lists no operational personnel is a member of this quick reaction organization, in order to guarantee the continuation of the operational process. During defence-stations the operational process, with still 24 hour-coverage, is extended to be instantly ready to react to a threat on all warfare-domains. This schedule determines the number of operational personnel on board. The remainder of the crew is divided in two divisions, alternating awake and on-duty for a total of 12 hours a day. They perform tasks from the support-process, but each division is a complete, trained “quick reaction -team”.

Figure 6.10-5. mechanisation of seamanship could reduce the total amount of crew



During action-stations the total crew is awake. All operational people are allocated to the operational process. As all domains were already fully covered in ‘defence-stations’ the extra personnel is used to create backup, more intelligence and assistance in the CIC and to locally man all the weapon systems for emergency control and reloading. The remainder of the crew is deployed in the quick-reaction process. Because of the immediate threat, everybody takes position, fully dressed and equipped, ready for action. It is clear that this schedule cannot be maintained for a long time. The crew doesn’t rest/sleep anymore and support work is suspended, except the preparation of a quick meal. Figure 6.10-6 shows the three schedules and the relative / absolute contribution of the three processes in each schedule. The left graph shows a conventional crew list with 160 crewmembers for a small frigate (reference RNLN M-frigates). The right graph shows the same information for a reduced crew on a 2000 ton Littoral Combatant (working out of example in this document).

The relative contribution in transit is more or less the same for both crew lists. The absolute contribution however is halved! Technical developments like automation, advisories, C4I and well-designed HMI (HCI, GUI), make the absolute reduction possible. Within the support-process many reduction measures can be thought of (see previous paragraph). Trade-off effects occur: reduction measures reduce the crew, reduced crew reduces ‘crew-support’-workload and so on. Most of the times the number, complexity and volume of installations is smaller on a Littoral Combatant, which results in a smaller maintenance demand. Moreover, using equipment with maintenance-conscious design (large MTBF, small MTTR, built-in test) can reduce the workload even more. The difference in relative contributing can be seen by defence-stations and action-stations. It is estimated that absolute operational demand under threat cannot be reduced that much. Some of the assumptions for this estimation are: the volume of information will increase with modern sensors and in a littoral environment (including C4I-handling), decision-making is still done by human, all warfare domains will still exist and need covering. The relative contribution of the primary-process ‘operations’ will therefore be larger compared to a conventional crew list on a 10-year old frigate as in the left graph. The quick-reaction process is under pressure due to absolute reduction of available crewmembers. Therefore it is important to optimize architecture, add structural protection, mechanize and automate fire fighting and install more active (or automatic switch-over) redundancy. Fighting battle damage can be more demanding if automated systems fail, which is not unthinkable in case of an explosion. It is important to determine priorities: operational needs versus quick-reaction needs. The operational core and quick-reaction core always exist, but some crewmembers may switch between the two processes. This is indicated in the graph with the red/blue block in the middle. 6.10.2.3.2.2 ‘8+4’ / ‘4+8’ hours working schedule On board small ships a lack of redundancy could be a problem. For example: when two functionaries cover one function for 24 hours and one of them drops out, it directly affects the operational effectiveness.

Figure 6.10-6. Difference in relative and absolute crew compilation in present situation and with a reduced crew

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The current ships’ management has several working schedules for the 24 hour day, for example a two-division schedule. To summarize, three disadvantages of the current two-division schedule exist: • tight schedules for operational tasks lead to a boring, non-inspiring programme for the day and long

‘on-station’ time (max 7 hours at a stretch, 12 hours a day). • Participants of the support process could have too little affinity with the operational task.

Furthermore, most of them only work 8-10 hours a day, while the operational service works at least 12 hours a day.

• With small crews there is a lack of redundancy for a considerable number of functionaries. The alternative is a schedule in which every crewmember works 12 hours a day, but conducted in accordance with the following conditions: • personnel of operational origin are arranged in 3 divisions, each strictly scheduled for 8 hours a day

working two periods of 4 hours at a stretch in the operational process. From the total working time of 12 hours a day, the remaining 4 hours are filled in with tasks from the support process, which mostly can be scheduled at any convenient time. If one functionary drops out, the remaining two functionaries fall back to a two division schedule for the critical operational task, postponing the support tasks or filling them in differently. This is called the 8+4 schedule.

• Personnel of support origin are assigned for a maximum of 8 hours to the support process, in the usual flexible schedule. The remaining 4 hours of the 12-hour working day will be filled in with scheduled operational tasks. The positive result is that everybody feels directly involved (needed) in the operational product. This is called the 4+8 schedule.

The above-mentioned alternative is an ideal. However, in practice it will not be possible to develop a crew list with a consistent 8+4 / 4+8 schedule (see for instance the Commanding Officer in figure 6.10-7). Nevertheless, it is possible to use the concept for key -functionaries and personnel that otherwise would have too little work satisfaction. 6.10.2.3.3 Job design In job design, individual human allocated tasks are combined into a workable job for a specific crewmember. The challenge is to design a job that has been optimised for all relevant human factors simultaneously. This challenge accumulates to the schedule problem as described in the previous paragraph. The relevant human factors are:

• psycho-social (job satisfaction) o standing, social status, respect, regard, prestige, esteem o social contacts o varied, diversified

• physical abilities and capacities o psychomotor o strength

• mental competences, abilities and capacities (global and specific) o cognitive abilities o susceptibility to stress o verbal, written expression o executive, analytical, multitasking

• education and experience

Figure 6.10-7. Example of a 8+4 working schedule for 1 day (24 hours)

off-duty sleep operational process support combination OPS+SUPP B / W bread/warm meal

time (hour) during a twenty-four hours' periodnr rank dept. function name 0 1 2 3 4 5 6 7 8 9 10 11 12 1 3 14 15 16 17 18 19 20 21 22 23

01 LtCdr OD Commanding Officer B R O V I N G W R O V I N G B R O V I N G02 Lt SR OD Senior Watchkeeping Officer B R I D G E B W B R I D G E B03 Lt JR OD Watchkeeping Officer B R I D G E B W B R I D G E04 Lt JR OD Watchkeeping Officer B B R U G W B B R I D G E.. ….. ….. ……



o level of education o functional education and training o military training o job experience (skill, practice, routine)

These factors can hardly be quantified and their interrelations are not yet well defined. A lot of research, has been done, is being carried out or has to be earmarked for future research. At this moment these factors are not used in a method or algorithm to design jobs, but only to check jobs that were designed by first of all gut-feeling and intuition. 6.10.2.4 Fleet management concepts As mentioned in the introduction, fleet management concepts deal with the management aspects of a complete fleet or class of ships. Concentrating on manning and in particular crew reduction, it is obvious that ship management concepts affect fleet management concepts. For example the maintenance cycle of a ship will be different with less maintenance personnel on board, so more maintenance must be executed ashore. Three (new) fleet management concepts with relation to manning are considered in the present stage of development:

• an integral manning concept • a modular manning concept • entire crew-replacement

6.10.2.4.1 Integral manning concept A more traditional way of designing a crew list. To fulfill all the expected ships missions with an integral crew and the use of existing, conservative technology results in a relative small reduction of the total crew. The highest peak in figure 3 dictates the total crew size. With this concept, the crew for a modern corvette will be around 120 people. 6.10.2.4.2 Modular manning concept The principle of this concept lays in splitting continuous operations and mission specific tasks. Modular teams are teams of persons (specialists) that are placed on board in order to perform specific tasks. These teams are placed on board only when needed. When modular teams are used, the crew of a ship consists of a fixed, mission-independent basic crew, consisting of a small number of persons (e.g., half of the current crew size), and a flexible number of modular teams. By employing modular teams, fewer personnel will be needed throughout the entire fleet because at a certain moment in time most ships will have missions that do not require all possible modular teams to be on board. (see also paragraph 6.10.4.2.2). For each peak in figure 6.10-3 a tailored and mission capable crew component will be added. For a modern corvette, this results in a base-crew of 45-50 people, which can be extended with (operational) modules when required, up to a total crew of 100 people for the most demanding mission. 6.10.2.4.3 Entire crew replacement Finally entire crew-replacement will be considered and could be applied for both integral and modular manning concepts. The USN claims an increase of the number of operational days for units stationed far from base (USN sea swap project). However, the philosophy of replacing an entire crew has an effect on the number of hulls to be built and on training aspects of the crew.

Figure6.10-8. An example of a modular team: a boarding team inspects a vessel



6.10.3 Application of the principles: an example 6.10.3.1 Introduction In this chapter the manning theory will be applied to the four point-designs used in the workgroup. Various examples will be given to illustrate the complexity of considerations and to show some important manning -decisions. The point-designs are based on two variables: 1. type: Offshore Patrol Vessel (OPV) and Small Littoral Combatant (SLC) 2. size: 600 and 2000 tonnes The choice for an OPV or a SLC depends on mission-need solely. Because the relation between type of ship and mission capability is clear, it is possible to link manning directly to missions and in this way work out the manning problem for the two types. The choice of the mission is the starting point of the crew compilation process. 6.10.3.2 Restrictions big and small tonnage The principles of designing a crew list are the same for small ships and large ships. Small ships have their restrictions like limited space for capabilities, storage, workshops and crew. This leads to less functional tasks, shorter time at sea and less maintenance facilities. In most of the cases this leads to a decreased workload. Knowledge and experience however are still needed over a wide range of activities. On one hand it sounds rational to reduce the number of crewmembers based on the decreased workload. But on the other hand we want to keep a range of expertise available and sometimes it is even necessary to have several expertises directly (autonomously) available. Due to the inability or cost to bring all the needed ex pertise together in the small resulting crew (cp. it is expensive and takes a lot of time to get all the needed expertise in an astronaut), we have an optimising problem. We have to optimise between the potential minimum number of crewmembers and the required number of incompatible expertises. An example to make it more clear: a highly automated system with high reliable components requires, based on maintenance, a workload of only 8 hours a day. Based on the given workload one person could do the job. However, at least three expertises are in depth needed with this system: mechanical, electro technical and computer engineering. As these expertises cannot easily be combined in one person, we need to find an optimal workable solution. We have to optimise between one person with a lot of support (i.e. remote knowledge, expert systems, diagnostic aids) and three persons, each representing a single expertise, but with supplementary workload (other non-conflicting tasks) to get an efficient use of each person. To summarize: It is the small size of a crew that makes the manning problem more demanding. Most of the times small crews are found on small ships. But highly automated large ships with a resulting small crew cope with the same optimisation problems. 6.10.3.3 Overall description of the crew compilation One of the first questions in the (pre) design process will be: “what will be the future mission or the future mission tasks of the ship?” This is a very important question, because with this the future employability of the ship is stipulated. In much literature, missions for small ships are found and these missions can be divided into mission tasks For small ships in this paper the next missions are defined:

• Military Aid • Military Patrol • Sea control • Power projection



When these questions about the future task of the ship has been answered, one of the missions above or a combination of missions can be chosen and the mission tasks of the ship can be determined. The selection of the mission tasks results in the requirement of some capabilities (see section 6.10.3.5). For example, the mission task “Embargoes & Sanctions”, implies the need for a high speed in order to pursue embargo breakers. So the capability that follows of the mission task “Embargoes & Sanctions” is a high speed. This high speed can be obtained either by own ship, fast rhib or helicopter. This capability is called a required capability (required to accomplish the mission). The designer still has some options in this phase of the design process. This procedure must be followed for all mission tasks, in order to determine all the required capabilities. As well as these required capabilities there are also “basic” capabilities and “additional” capabilities. The basic capabilities are all the capabilities needed for at least a transit of the ship from A to B. So basic capabilities can be the propulsion, the platform itself, cooking capabilities etc (see paragraph 6.10.3.5.1). Additional capabilities are capabilities which are desired for that specific mission task. After considering all the required and additional capabilities, a final set of capabilities can be chosen. For example, for a certain mission task a rhib is a required capability and a helicopter is an additional capability. For that specific mission task, the rhib will be chosen because the helicopter is just desired and not really needed. However, for an other mission task, the helicopter is definitely required. This can influence the final choice of the capability; the rhib or the helicopter. Generally, additional capabilities are mostly the more expensive alternatives and therefore dependent of the total design budget. When all the capabilities are surveyed, a final set of capabilities has to be chosen. In this stage of the design process the mission(s), mission tasks and the final set of capabilities are known and they will be the starting point in the crew list design. The next step is to determine the function tasks from the capabilities. Many of the capabilities are system requirements. For example, an air surveillance radar can be a capability. This capability implies the need for a certain number of competent personnel to operate and maintain this radar. Also the duration, the work load, the time load, frequency etc. of a function task and the instructed number of people required to execute that particular function task (i.e. for safety reasons) must be considered. For example, is it necessary to provide air surveillance twenty-four hours a day or only twelve hours a day? A twenty-four hours air surveillance coverage demands more personnel than coverage of twelve hours. So at the end, the result of this step is a list of all function tasks with their duration, workload, time load, frequency etc. and a rough estimation of the amount of personnel necessary for the execution of the function tasks. Now the simultaneity and possible combinations of function tasks must be considered. Simultaneity of many function tasks is required, for example the simultaneity of radar operations, navigation, transit, cooking, technical maintenance etc. Overlapping of function tasks demands more personnel than a sequential execution of function tasks. Furthermore, other very important function tasks are quick reaction operations. Quick reactions, for example, are fire fighting, damage control, damage repair etc. During the whole process of crew list design it is important to check the feasibility of the execution of quick reactions with the crew determined After all these considerations, the result is a theoretical crew list. The last step is to apply job design features and to check for working schedule problems. (see section 6.10.2.3.2 and 6.10.2.3.3) The final result is the requested crew list. Basically the total crew amount is a combination of three parts:

a) basic crew as a consequence of the basic capabilities b) crew as a consequence of the required capabilities



c) crew as a consequence of the additional capabilities To determine the total crew amount the superposition principle can be used. Total the amount of people from a), b) and c) and this results in the total crew number (remember the check mentioned above about the feasibility of executing quick reactions). In this paper some examples of the above schedules and tables are given to clarify this description of crew compilation. Also an example of mission analysis and the determination of corresponding capabilities are described. Not all steps are elaborated in this paper, because to copy out all the possibilities is beyond the scope of the paper. An attendant problem is the lack of detail information about the ship’s performance, so in the next schedules and tables many assumptions are incorporated. Generally, the performance of current, modern ship’s types, like a FPB and corvette, forms the base of the performance of the four point designs. 6.10.3.4 Mission and mission tasks For the four point-designs the missions and their corresponding mission tasks are shown in the figures below. The yellow color corresponds with the missions and mission tasks of the OPV and the red color corresponds with the missions and mission tasks of the SLC. The first two missions (Military Patrol and Military Aid) are mainly OPV missions, however, the SLC must be able to accomplish these mission also, although she is not optimized for these missions. That explains the red border around the yellow squares. The third and fourth mission (Sea Control and Power Projection) are SLC missions, this explains the red square.

Disaster Relief HumanitarianOperations

Non CombattantEvacuation Operations

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Search andRescue (SAR)

Military Aid

Maritime Security Border Patrol Safety of Navigationat sea

EnvironmentalProtection

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GatheringInformation

Protect Sealines of

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Protect HighValue Units

(HVU)

Embargoes &Sanctions

Sea control

AmphibiousOperations

NeutraliseNaval Force

AirCampaign

LandCampaign

Power Projection

Figure 6.10-9 OPV and SLC Missions and Tasks



6.10.3.5 Capabilities and function tasks 6.10.3.5.1 Additional and required capabilities In this stage, the mission and the mission tasks of the ship are known. Now, the capabilities have to be determined. In the next figure, the required and additional capabilities are shown. The different colors correspond with the four point designs, and indicate which capabilities are required (or additional) for the realization of the different mission tasks.

Figure. 6.10-10. Required and additional capabilities per mission task and ship type

Military Aid Military Patrol Sea control Power projection

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CapabilitiesRhib R R R R R R R R, RSecond Rhib R R R A A AHelicopter A A A A A A R A, A A, A RUnmanned air vehicle (UAV) A, R A, AHigh ship's speed R R R, R R, R R, R R, RSurface to surface missiles (SSM) R, R R, R R, R R, RSurface to air missiles (SAM) R R R R R, RVertical launch system (VLS) RClose-in weapon system (CIWS) R, R R, R R, R R, R R, RElectronic support and counter measures (ESM/ECM) R, R R, R R, RTorpedo's R R RMine laying R, RMine counter measures (MCM) R, RGun (small kaliber) R R R R, R R, R RGun (medium kaliber) R R R R R, R R, R(additional) (secure) Communications R A R R, R R, R R, R A,R, R R, R R, R R, R R, RNight vision goggles (NVG) R R, R R, RRecognised maritime picture (RMP) R R R, R R, R R, R R, R R, RRecognised air picture (RAP) A A, R R, R R, R R, R R, R R, RRecognised underwater picture (RUP) R R RBoarding team R R R R, RDiver(s) A A AMedical personnel and epuipment R R RGuard team R, RISR team RAdditional hotel facilities R R R R R R R, R R, RAdditional potable water production AAdditional fire fighting equipment A ANeutralization of oil pollution A

R = required capability for all point designsA = additional capability for 600 ton OPVR/A = required/additional capability for 2000 ton OPVR/A = required/additional capability for 600 ton SLCR/A = required/additional capability for 2000 ton SLC



6.10.3.5.2 Function tasks As stated in section 6.10.3.3 the function tasks must be determined from the capabilities. The schedule below shows the function tasks and also a rough estimation of the demanded people to fulfill these function tasks. In this figure, the duration, workload, time load, frequency etc. of function tasks is not taken into account. To consider these variables, much more information about the demanding ship’s performance is needed. For example: when for the realization of a function task two people are needed, nothing is said about the time required for this realization. It is possible that the (totally) required time for the realization of the function task is just 2 hours, so the two people still have time for other function tasks. Simply sum the number of people in the table below is anything but good. We therefore emphasize that the figure below is just an example. In the table below, competence clusters are used, for an explanation of these competence clusters see paragraph 6.10.3.6.1.

COMPETENCE CLUSTERS OPS & COMMS

SAILING & GEN. WEAPONS PLATFORM PERSONNEL

CAPABILITIES FUNCTION TASKS

OFF

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Rhib execute rhib operations 2 rhib maintenance 1 launch rhib 1 2 Second Rhib execute rhib 2 operations 2 rhib 2 maintenance 1 launch rhib 2 1 2 Helicopter execute helicopter ope rations 2 1 control helicopter operations (deck) 1 control helicopter operations (CIC) 1 1 helicopter maintenance 1 2 2 2 1 Unmanned air vehicle (UAV) execute UAV operations 1 1 UAV maintenance 1 2 1 1 1 control UAV operations 1 1 High ship's speed (mobility planned maintenance propulsion system 2 2 4 support) corrective maintenance propulsion 1 1 1 control and monitoring propulsion 3 6 operate propulsion system (emergency) 3 1 2 4 operate propulsion system (normal) 3 Surface to surface missile (SSM) weapon system tests 1 1 SSM (system) planned maintenance 1 SSM (system) corrective maintenance 1 1 1 Control and monitoring SSM (system) 2






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operate SSM (weapon attack) 1 1 SSM replenishment 1 1 1 Surface to air missile (SAM) weapon system tests 1 1 SAM (system) planned maintenance 1 SAM (system) corrective maintenance 1 1 1 Control and monitoring SAM (system) 2 operate SAM (weapon attack) 1 1 SAM replenishment 1 1 1 Vertical launch system (VLS) weapon system tests 1 1 VLS (system) planned maintenance 1 VLS (system) corrective maintenance 1 1 1 Control and monitoring VLS (system) 2 operate VLS (weapon attack) 1 1 replenishment VLS 1 1 1 Close-in weapon system (CIWS) weapon system tests 1 1 CIWS (system) planned maintenance 1 CIWS (system) corrective maintenance 1 1 1 Control and monitoring CIWS (system) 2 operate CIWS (weapon attack) 1 1 2 CIWS replenishment 1 1 Electronic support/counter ESM/ECM system tests 1 measures (ESM/ECM) ESM/ECM planned maintenance 1 ESM/ECM corrective maintenance 1 1 Control and monitoring ESM/ECM 1 1 utilize ESM, use ECM 1 1 1 Torpedo's weapon system tests 1 1 torpedo planned maintenance 1 1 torpedo corrective maintenance 1 1 1 Control and monitoring torpedo 2 operate torpedo (weapon attack) 1 1 torpedo replenishment 1 2






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Mine laying operate mine detection sonar 2 operate mine classification sonar 2 storage of mines 1 operate mine laying system 1 2 Mine counter measures (MCM) operate mine detection sonar 2 operate mine classification sonar 2 storage explosive devices 1 execute MCM diving operations 1 1 1 1 2 execute UUV operations 2 1 1 2 1 1 Gun (small kaliber <1") weapon system tests 1 1 Gun (system) planned maintenance 1 1 Gun (system) corrective maintenance 1 1 Control and monitoring Gun (system) 1 operate Gun (weapon attack) 1 1 1 ammunition replenishment 2 load gun 1 Gun (medium kaliber >1") weapon system tests 1 1 Gun (system) planned maintenance 1 1 Gun (system) corrective maintenance 1 1 1 Control and monitoring Gun (system) 1 operate Gun (weapon attack) 1 1 2 ammunition replenishment 4 load turret 2 (additional) (secure) operate communication 1 1 2 Communications communication maintenance and repairs 1 1 Night vision goggles (NVG) operate NVG 3 NVG maintenance and repairs 1 Recognized maritime picture operate radar 2 2 (RMP) lookout from bridge 3 3 threat analysis 2 2 3






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radar maintenance and repairs 1 1 1 Recognized air picture (RAP) operate radar 2 2 lookout from bridge 3 3 threat analysis 2 2 3 radar maintenance and repairs 1 1 1 Recognized underwater picture operate sonar 2 (RUP) threat analysis 2 2 sonar maintenance and repairs 1 1 1 Boarding team execute boarding operations 1 1 2 3 1 1 1 2 1 1 storage boarding team devices 2 Diver(s) execute diving operations 1 1 2 storage diving equipment 1 Medical personnel and equipment storage medical equipment 1 administration 1 1 treat and nurse patients 1 1 1 2 storage medicines 1 Guard team execute guard team operations 1 1 2 4 storage guard team equipment 2 ISR team execute ISR team operations 1 1 4 storage ISR team equipment 1 Additional hotel facilities (100 p) laundry 2 restaurant 1 4 Additional potable water operate production equipment 1 production maintenance production equipment 1 1 control & monitoring prod. equipment 3 Additional fire fighting equipment operate fire fighting equipment 2 4 maintenance fire fighting equipment 1 1 control & monitoring fire fighting equip. 1 3 Neutralization of oil pollution execute neutralization operations 1 1 2 4 1 Abbreviations: OFF: Officer PO: Petty officer

CPO: Chief petty officer RAT: Rating Figure 6.10-11. Function task



166

6.10.3.6 Simultaneity 6.10.3.6.1 Introduction Simultaneous performance can be regarded at every level. From a high level regarding the simultaneous demand of capabilities as a whole and from a low level regarding the single activities within a functional task cluster. Simultaneity at a high level is derived from scenario-analysis. For example, for a 600 ton OPV the most demanding scenario is sailing with moderate surface threat, a boarding of a suspect vessel in progress and a fire with some wounded people occurring. This scenario needs a simultaneous deployment of the capabilities: navigation and communication, small caliber guns for self protection, rhib, boarding team, medical, calamity control and even some technical support for the ship’s mobility installation is still required. However, most of the missions of the OPV-600 do not require a boarding team, or at least not a large boarding team. Therefore it would be wise to make the capability/functional task ‘boarding team’ modular. In this way, the OPV can fulfill most of his deployments and if boarding’s can be expected, a boarding team can be added modular. The same goes for other capabilities of the 600-ton OPV: extra medical personnel, build up a recognized air picture (RAP), additional hotel facilities and neutralization of oil pollution. At a lower level tasks within a cluster belonging to a capability can be regarded. Some tasks can be performed sequentially, for other tasks it is necessary to perform them simultaneously. An example is replenishment of a missile and launching the missile. These tasks will never be demanded simultaneously because replenishment is always done in times without or with low threat and launching is always done in direct threat situations. Other variables that we use to construct the final theoretical crew list are: time load, workload, (expected) frequency of occurrence, required competence, can the tasks be planned? can it be delayed (time-critical)? and so on. These variables are in the (pre-)design phase only available as estimates from experience (domain experts) and therefore the process to derive a crew list is a bit obscure at this stage and the outcome contains some uncertainties. As the design process spirals towards a more detailed level, these variables are better available and the crew list can be designed more accurately. However, experience learns that estimates in the pre-design phase have a small margin with respect to the final crew list. In paragraph 6.10.3.6.2.2 an example is given of a possible simultaneity table of the 2000 ton SLC. Using a top-down approach we consider the following competence clusters (see paragraph 6.10.3.6.2): Personnel support, Materiel/platform support, Weapons support, Operations and communication, Sailing and seamanship and General (from all departments). The functional tasks that have been derived from the required (additional) and basic capabilities can be accommodated in a competence cluster. Some functional tasks cannot easily be accommodated in a competence cluster because it is common practice that they are performed by crewmembers from all departments (i.e. Damage Control / Fire Fighting). Therefore we check the availability of required personnel for these tasks separately considering all personnel from all departments (see also section 6.10.3.3). Accounting for simultaneity on every level, it is possible to estimate the number of crewmembers required in each competence cluster. Having done that, it is possible to link each individual task to individual crewmembers. 6.10.3.6.2 Simultaneity of capabilities 6.10.3.6.2.1 General In section 2.5 the possible capabilities for the four point designs are defined. In this section an example of the simultaneity of capabilities is given. Normally the content of the matrix is completed by Naval Staff.



167

Only one table is given: a possible simultaneity table of the 2000 ton SLC. Comparing two ships of one type (i.e. the OPV or the SLC), it can be said that the 2000-ton SLC should execute more capabilities simultaneously than the 600 ton SLC and also that the 2000-ton OPV should execute more capabilities simultaneously than the 600-ton OPV. Generally, based on the simultaneity of capabilities the crew of the larger ship will be larger than the crew of the smaller type. Comparing two different ship types is difficult, because of the different missions and mission tasks of the ships. In the figures the legend is as follows:

• a green square means: these capabilities must be executed simultaneously • a purple square means: for these capabilities it is desired to be executed simultaneously • a yellow square means: for these capabilities it is not needed to be executed simultaneously or it

is not relevant • a red square means: these capabilities cannot be executed simultaneously

The squares with a green color directly affect the total amount of people on board of the ship, because all these capabilities must be executed simultaneously. In the crew design process the same simultaneity table must be determined for function tasks. This table will have a more detailed content and is performed at a lower abstraction level. Once again, it is beyond the scope of this paper to show the more detailed matrix of the function tasks, because the principle of derivation is just the same as showed over here for the capabilities. The competence clusters indicated at the left side of the figure (indicated with colors) in combination with the average workload, time load and duration of function tasks are the starting point for the final step in the crew compilation.



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Example: 2000 ton SLC

Figure 6.10-12. Simultaneity table regarding capabilities

SIMULTANEITY SLC2000

Laun

dry

Res

taur

ant

Adm

inis

tratio

n

Med

ical

War

ehou

se m

anag

emen

t

Cle

anin

g

Nav

igat

ion

and

com

mun

icat

ion

Ber

thin

g

Sew

aco

supp

ort (

mai

nten

ance

and

rep

airs

)

Hot

el s

uppo

rt (

mai

nten

ance

and

rep

airs

)

Cas

co/p

latfo

rm s

uppo

rt (

mai

nten

ance

and

rep

airs

)

Cal

amity

con

trol

(re

pres

sion

)

Rhi

b

Sec

ond

rhib

Hel

icop

ter

Unm

anne

d ai

r ve

hicl

e (U

AV

)

Hig

h sh

ip's

spe

ed

Sur

face

to s

urfa

ce m

issi

les

(SS

M)

Sur

face

to a

ir m

issi

le (

SA

M)

Ver

tical

laun

ch s

yste

m (

VLS

)

Clo

se-in

wea

pon

syst

em (

CIW

S)

Ele

ctro

nic

supp

ort a

nd c

ount

er m

easu

res

(ES

M/E

CM

)

Tor

pedo

's

Min

e la

ying

Min

e co

unte

r m

easu

res

(MC

M)

Gun

(sm

all k

alib

er)

Gun

(m

ediu

m k

alib

er)

(add

ition

al)

(sec

ure)

Com

mun

icat

ions

Nig

ht v

isio

n go

ggle

s (N

VG

)

Rec

ogni

sed

mar

itim

e pi

ctur

e (R

MP

)

Rec

ogni

sed

air

pict

ure

(RA

P)

Rec

ogni

sed

unde

rwat

er p

ictu

re (

RU

P)

Boa

rdin

g te

am

Div

er(s

)

Med

ical

per

sonn

el a

nd e

puip

men

t

Gua

rd t

eam

ISR

tea

m

Add

ition

al h

otel

faci

litie

s

P Laundry

P Restaurant

P Administration

P Medical

P Warehouse management

P Cleaning

S Navigation and communication

S Berthing

M Sewaco support (maintenance and repairs)

M Hotel support (maintenance and repairs)

M Casco/platform support (maintenance and repairs)

GEN Calamity control (repression)

S Rhib

S Second rhib

O Helicopter

O Unmanned air vehicle (UAV)

M High ship's speed

W Surface to surface missiles (SSM)

W Surface to air missile (SAM)

W Vertical launch system (VLS)

W Close-in weapon system (CIWS)

W Electronic support and counter measures (ESM/ECM)

W Torpedo's

W Mine laying

W Mine counter measures (MCM)

W Gun (small kaliber)

W Gun (medium kaliber)

W (additional) (secure) Communications

O Night vision goggles (NVG)

O Recognised maritime picture (RMP)

O Recognised air picture (RAP)

O Recognised underwater picture (RUP)

GEN or S Boarding team

S Diver(s)

P Medical personnel and epuipment

GEN or S Guard team

O ISR team

P Additional hotel facilities

P Personnel support these capabilities must be executed simultaneouslyM Mateiel support for these capabilities it is desired to be executed simultanieuslyW Weapons support for these capabilities it is not needed to be executed simultaneously or it is not relevantO Operations and communication these capabilities cannot be executed simultaneouslyS Sailing and seamanshipGEN form all departments



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6.10.3.7 Results of the crew compilation 6.10.3.7.1 Basic crew

The figure above shows an example of the basic capabilities with the basic function tasks and an estimation of the amount of people necessary for these basic function tasks. The characters between brackets refer to the competence clusters defined in paragraph 6.10.3.6.1. P = personnel support M = materiel/platform support W = weapons support O = operations and communications S = sailing and seamanship GEN = from all departments. The number of people in the table above is based on “hands-on” experts and the (operational) management of comparable ships. Once again, to copy out all the possibilities to determinate the final number of basic crew is beyond the scope of this paper, because many factors are not yet taken into account, like frequency of tasks, simultaneity of function tasks, job design, working schedule problems, workload etc. So a definitive amount of the basic crew cannot not be given. 6.10.3.7.2 Total crew In this chapter the process of crew compilation is described and some clarifying figures and tables are shown. Not all the required steps in crew design are copied out, mainly because of the lack of detailed information about the ship’s performance. Also, to write out all the possibilities with respect to all the variables results into an enormous amount of work while the jumble of tables doesn’t stimulate the understanding of the crew compilation process. Like stated in paragraph 6.10.3.3 the crew list design process consists of several steps:

o mission analysis o determination of mission tasks and the choice of capabilities o consideration of simultaneity and possible combinations of function tasks o defining a “rough” crew list o checking for feasibility of quick reaction operations o applying job design features and checking for working schedule problems o defining final crew list

Figure 6.10-13. Basic crew

Number of personnel:Basic capabilities OPV 600 ton OPV 2000 ton LC 600 ton LC 2000 tonPersonnel support Laundry 0 2 (P) 0 2 (P)

Restaurant 3 (P) 5 (P) 3 (P) 5 (P)Administration 1 (P) 1 (P) 1 (P) 1 (P)Medical 1 (P) 1 (P) 1 (P) 1 (P)Warehouse management 1 (P) 2 (P) 1 (P) 2 (P)Cleaning additional task additional task additional task additional task

Operations Navigation and communication 6 (S) 6 (S) 6 (S) 6 (S)Berthing 1 (S)+additional task 2 (S)+addtional task 1 (S)+addtional task 2 (S)+addtional task

Materiel support Sewaco support (maintenance and repairs) 3 (W) 4 (W) 5 (W) 8 (W)Hotel support (maintenance and repairs) 2 (M) 4 (M) 3 (M) 6 (M)Platform support (maintenance and repairs) 2 (M) + 1 (S) 2 (M) + 3 (S) 2 (M) + 1 (S) 2 (M) + 3 (S)

Quick Reaction Calamity control (repression) 15 (GEN) 20 (GEN) 35 (GEN) 45 (GEN)



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It is very clear that this is an iterative process. Notwithstanding the lack of information about the ship’s performance an example of a final crew list is given for the four point designs. We will emphasize that this final result is based on the assumption that the performances of the four point designs equal the performances of current, modern ship types like Corvettes and FPB’s. Work load, time load, duration, frequency etc. of function tasks are estimated based on experience and other (theoretical) manning studies. For the construction of the table, the following items are used:

o the table of the basic crew o the table of function tasks with corresponding numbers (figure 6.10-11) o the table of simultaneity (figure 6.10-12)

The characters between brackets refer to the competence clusters defined in paragraph 6.10.3.6.1 P = personnel support M = materiel/platform support W = weapons support O = operations and communications S = sailing and seamanship Clusters of function tasks

600 OPV 2000 OPV 600 LC 2000 LC

(Bridge) navigation and seamanship

7 (S) 8 (S) 7 (S) 8 (S)

Command and communication

4 (O) 4 (O) 7 (O) 9 (O)

Helicopter and UAV operations

- 4 (O) + 4(M) + 2 (W)

3 (O) + 1 (M) + 1 (W)

4 (O) + 4 (M) + 2 (W)

C&M weapons and sensors

6 (O) 8 (O) 10 (O) + 3 (W) 14 (O) + 4 (W)

Maintenance weapons and sensors

3 (W) 4 (W) 5 (W) 8 (W)

C&M Platform 3 (M) 6 (M) 3 (M) 6 (M) Platform support and hotel support

4 (M) + 1(S)

6 (M) + 3 (S) 5 (M) + 1(S) 8 (M) + 3 (S)

Damage control additional function

1 (M) 2 (M) 2 (M)

service (logistic) and (medical) care of personnel

5 (P) 9 (P) 5 (P) 9 (P)

replenishment (administration and logistic)

1 (P) 2 (P) 1 (P) 2 (P)

total estimation RNlN

34 61 54 83

total estimation USCG

30 88 48 110

Figure 6.10-14. Example of final crew list



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6.10.4 Trends and future research 6.10.4.1 Introduction To achieve a low number of basic crew personnel, the following items can be introduced: • unmanned ships control centre (SCC): insertion of more automation, the use of new technology and

the transfer of most of the control and monitoring tasks to the bridge and combat information centre (CIC) eventually will result in a unmanned SCC. Conditions to be met are: introduction of reliable autonomous systems and aids to achieve acceptable operator loads.

• reduce the preventive maintenance and where possible: transfer from the ships’ to the shore organization;

• introduce more generally educated personnel able to perform both operational and support tasks onboard (flexibility);

• the application of knowledge-at-a-distance with specialists ashore is necessary to compensate for the more general knowledge level of the crew, for example in case of a corrective maintenance action at sea;

• use more mechanization to reduce the nautical workload on deck; • a change of the damage control philosophy, first actions performed by built-in systems.

Containing of the damage done by people. The continuous operation like safe sailing and self defence will be done by the basic crew. Some of the above items will be discussed in the following paragraphs. 6.10.4.2 Trends 6.10.4.2.1 Life on board One of the trends observed, is the increase of personal demands for rest and recreation against a decrease of the need for a high service level on board of a ship. For example, current personnel on board rather prefer an Internet connection in their cabin, than a steward serving their meal. Central messing therefore, is an option to consider in the crew reduction process. On board of current ships, all ranks have their own mess, three in total. In a study “central messing” all aspects of combining these three messes into one were evaluated. Topics discussed are: • Accommodation space as laid down in design

rules • Management of the necessary logistic personnel

on board • Hygiene as laid down in national and navy rules,

from storing the raw ingredients to processing the litter

• Cultural aspects in having a meal • International developments; what are other navy’s

doing and observing trends within the commercial shipping world

6.10.4.2.2 Modular Teams For mission specific tasks modular teams will be added when needed, as mentioned in paragraph 6.10.2.4.2. At this moment, modular teams can already be found on board of naval ships. Examples are helicopter teams and boarding teams. A boarding team consists of personnel of the Special Forces that

Figure 6.10-15. Central messing



172

are placed on board of a naval ship and is put into action to intercept suspicious ships and search them (for example for terrorists). One of the problems of using modular teams is that a group of persons has to work together for a certain period of time before the group becomes a real team (in this case a crew). This process is called team development. A modular team that is placed on board of a naval ship may not have had sufficient time to learn to work together. In every case the team should have sufficient time to work together with the basic crew or other modular teams with which they must form a unity. If this problem is not recognized during the design of the crew structure, the operational effectiveness of the naval ship will decrease. However, one requirement that must be met, is that the operational effectiveness is not compromised by the use of modular teams. There are two different types of modular teams: the modular team as strengthening and the modular team as expansion. The modular team “as strengthening” means a team that is added to the ship’s crew in order to help them carry out their tasks. The modular team “as expansion” means a team that is placed on board of a ship in order to carry out a new, separate task. In the case of strengthening, aspects within the team prevail. In the case of expansion, aspects between the teams prevail. Furthermore, there are other aspects that affect the performance of a modular team such as social aspects, education and training aspects, pool aspects (where do the team members come from when they are placed on board?) and cultural aspects. 6.10.4.2.3 Knowledge-at-a-distance Many tasks on ships, like maintenance, medical care and administrative tasks, are carried out by knowledgeable and experienced experts. These experts are constantly on board, even though their expertise is only required incidentally (e.g. during malfunctions or illnesses). A potentially successful way to reduce the number of crewmembers could come from reducing the amount of occasional, knowledge-intensive tasks that are not directly critical to successful mission performance. However, the knowledge required for these tasks must still be available to the crew if an emergency occurs. Therefore, a facility must be set up that enables crewmembers to occasionally have this knowledge at their disposal. Such a facility could be a shore-based centre where ships can obtain specialized knowledge on a 24-hour basis. Experts who work in this centre may not only put their knowledge and experience at the ship’s disposal, they may also use their expertise to maintain and control installations and instruments from a distance (so-called tele-operations). Fitting out such helpdesks raises a number of questions. For example, it is unclear which tasks are suitable to be co-ordinated from a distance and whether this is true for all operational situations. In addition, it is unclear what information and communication means must be available to support the user on board and ashore to ensure that knowledge is available at the right time, in the right context, and to enable the users to interact efficiently. Finally, the psychosocial conditions (e.g. how must responsibility for a task be delegated; how is task commitment assured; how can task impoverishment be prevented), important for applying knowledge-at-a-distance, must be considered. 6.10.4.3 Present and future research Research and Development (R&D) has, on many occasions, been accepted as the most important factor in manning reduction. This judgment still holds very much value, but the focus of R&D needs to be

Figure 6.10-16. Knowledge-at-a-distance



173

redirected. The consensus used to be that technological innovation is the most important factor with respect to manning reduction. Consequently it is more or less possible to address the relationship between technology, operational value (ambition) and costs. But truly, the whole process is just making the first baby steps when it comes to issues of an organizational and cultural nature. Further steps in manning reduction require R&D focused on organizational and cultural issues. 6.10.4.3.1 Robust Automation A naval ship must be able to withstand considerable damage. Damage can be caused by weapons of the enemy (missile hit), or a failure in a platform system. It is the task of the crewmembers and especially the operators in the Ship Control Centre (SCC), to limit the consequences of the damage. This can be realized by reconfiguring damaged systems in order to restore function and by deactivating more damaged systems to prevent further damage. Reconfiguring a system means that the function of the system can also be realized in another way, for instance by activating backup equipment, i.e. redundancy. An example of such a system is the chilled water system that provides cooling for sensor, weapon and command systems.

There are two reasons why naval ships can withstand less damage than is desired. First, the automation of the platform systems is centralized, which means that damage may deactivate all or a significant part of the automation (there are single points of failure, e.g. the Local Processing Units). Secondly, a damage causes problems for the operators in the SCC because (1) the operators have to process a lot of information in a short period of time (e.g., a very large number of alarms) and (2) they have to carry out many actions in a short period of time in order to reconfigure or deactivate damaged systems. The workload, including the mental workload, becomes so high that the performance of the operators decreases.

The object of robust automation is to solve these two problems by (1) making the automation of the platform systems more robust and (2) leaving more tasks to the platform automation so that the workload of the operators decreases. The robustness is realized by making the automation distributed instead of central. This means that every component (sensor or actuator) must have computer capacity. Also, the components must be able to communicate with each other via a redundant data network that is present everywhere in the ship. These components with their local automation have to be so intelligent that they can co-operate and carry out tasks autonomously (i.e., without intervention of the operators). For example, the components in the chilled water system can isolate a leakage autonomously and subsequently, they can restore the function of the system by reconfiguring it. Using robust automation, the workload of the operators in the SCC is reduced. As a result, fewer operators are needed. 6.10.4.3.2 Integration bridge, ship control centre (SCC) and Combat Information Centre (CIC) Despite the evolution of ‘Control and Monitoring’ (C&M), the number of personnel in the Ship’s Control Centres (SCC) of the Multi-purpose- and the new Air Defence Command Frigates (ADCF) of the RNlN is not significantly reduced compared to an older Standard-frigate. This is caused by a lack of attention paid to automation. Until now most effort was put in digitizing signals. User-support functions introduced on the ADCF are improvements that help to lower the complexity and, consequently, lower the operator load. Nevertheless, as long as there is interaction needed between man and machine (human in the loop), watchkeeping personnel in the SCC are necessary. Therefore, it is not efficient to focus on bringing the

Figure 6.10-17. Chilled water system



174

user-support to perfection. The result would be bored people, which is not desirable from the efficiency and human-factors point of view. The next revolutionary step that must be made is to fully remove personnel from the C&M-loop (unmanned SCC). To simply shift the tasks to the bridge or Combat Information Centre (CIC) is not a sound solution because this could lead to an operator overload in critical situations. The opposite solution is the automation of all systems. However, sometimes (unpredictable) operational priority or safety prevails the technical priority. For example: tripping an engine to avoid damage is not sensible or desirable if a direct threat of collision at sea is present. A compromise is a combination of shifting a limited set of C&M-tasks to the bridge or CIC and automation the remainder part. In the design of an unmanned SCC, three major challenges have to be met: I. robustness of automation: a small probability of system failure must be assured before removing human out of the loop. II. control of operator load: bridge personnel or CIC personnel will have C&M as an additional task. At critical moments the primary tasks (regarding safety of ship and crew) might suppress important C&M tasks. III. Development of user-support: the level of support and user-interface have to be adapted to the knowledge level of the new users. Detailed information will be available closer to the equipment and system information will be available at several strategic places around the ship. As a result people will work closer to the installations, which is good for efficiency and a better work satisfaction. 6.10.4.3.3 Advanced concepts for damage control 6.10.4.3.3.1 Introduction The trend in ship design is to combine a larger number of tasks with a smaller number of crewmembers aboard. This requires some radical changes in design philosophy, especially with respect to damage control, which requires a lot of manpower. A new, smaller, damage control organization will have to rely more on automation and structural measures to ensure effectiveness. But how to balance these design parameters? A possibility is the use of the Advanced Concepts for Damage Control (ACDC), a simulation tool developed by TNO-FEL. ACDC simulates the effects of calamities on board ships (for example explosions due to missile hits and fire) and the following damage control actions. The effectiveness of the damage control organization determines the amount of residual damage to the ship. The simulations incorporate differences in ship construction, level of automation, sensor suite within the ship, damage control organization and procedures, the number of people on board, etc.

Figure 6.10-18. SCC console on the bridge of HNLMS Rotterdam



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6.10.4.3.3.2 ACDC results The first results of ACDC simulations have been presented in 2002. The damage control process starts with reconnaissance. The personnel organization has to be activated, which in this case is difficult because the organization has to be rearranged due to the many casualties. After a while, the fire-fighting attack, boundary cooling and specialist task actions start. The spread of fire can be observed as the rise in temperature in various compartments. The attack of the fire, causes a significant decrease in temperature until the fire is extinguished. Simulation shows the response time of the damage control organization compared to the speed of the development of the fire. Generally speaking, the faster the response, the slower the development of the fire. ACDC can assess the effectiveness of, for example, measures to improve the response times of fire-fighting attacks. It can also assess the effectiveness of design measures to slow down the development of the fire. For example: what is a more effective solution, attacking the fire 5 minutes earlier, or installing bulkheads that withstand the fire twice as long? 6.10.4.3.3.3 ACDC capabilities RESIST, as a part of ACDC, simulates the physical damage to a ship. It can simulate the primary damage due to fragments and blast caused by explosions. Also the secondary damage due to the spread of fire and smoke can be simulated. Finally, the effects of fire fighting actions are simulated, such as the use of fire hoses, sprinklers, inert gasses, halon installation, water mist, etc. The ability to simulate the effects of fire-fighting has been developed recently. These simulations comprise ship design variations concerning, among other things, the type of fire resistant bulkheads, the spatial separation of dangerous/valuable compartments and the quantity and type of combustibles. DCAM, the other part of ACDC, is a discrete event process simulation of the damage control actions performed by the damage control organization and/or automated systems. DCAM simulates the people on board the ship who manage or perform the damage control actions. The actions are based on the current procedures on board ships. Processes are influenced by the availability of people, the available communication systems, the environmental conditions such as heat, smoke or obstacles, availability of damage control systems, the sensor suite, etc. 6.10.4.3.3.4 Reduced manning Damage control on frigates requires up to a hundred people for large calamities. Damage control is one of the manning drivers for navy ships. When the complement has to be reduced significantly, the manning requirements for damage control also have to be reduced significantly. Simulation is an essential tool to assess the manning requirements for damage control in the early stages of ship design. 6.10.4.3.3.5 Future developments The ACDC framework is still under development. At the moment ACDC is suitable for performing trend analyses, sensitivity analyses and comparative analyses. This is adequate for performing preliminary analyses on ship design and manning requirements for damage control. Aspects of the framework that have to be investigated further are, among other things, the spread of fire through bulkheads and the tolerance of people for heat and smoke. It is also expected that other processes like the transport of casualties and battle damage repair have to be implemented. Also the impact of battle stress on personnel must be investigated. Finally the interface has to be made more user friendly and the visualization of the damage control process should be improved. 6.11 Life-Cycle Cost All of the expenses associated with a ship that occur during its life are used to calculate the life-cycle cost (LCC). Comparing their life-cycle costs is a common way to evaluate different alternatives. Life-cycle costs can be compared using Present Worth (P/W), Future Value (F/V), or Annual Costs. Life-cycle cost encompasses all costs associated with the product's life-cycle. These include all costs involved in acquisition (research & development, design, production & construction, and phase-in), operation and



176

support, and scrapping of the ship. The LCC is determined by identifying the applicable functions in each phase of the life-cycle, costing these functions, applying the appropriate costs by function on a year-to-year schedule, and ultimately accumulating the costs for the entire span of the life-cycle. The cost of ownership, a subset of LCC, includes costs associated with operating, modifying, maintaining, supplying and supporting the SLC or OPV. A cash flow diagram is sometimes used to show how money is spent. The cash flow diagram generally includes the following:

• The initial cost is the price that is paid for the ship.

• Annual operating and maintenance costs include the annual cost of fuel, oil, fluids, personnel, consumables and other costs that occur every year.

• Periodic maintenance costs include maintenance costs that occur throughout the life of the ship to keep it in service.

• The salvage or scrap value is the price that the ship is sold for at the end of its useful life.

A simple cash flow diagram is shown in Figure 6.11-1. In this figure, each vertical bar represents the net expense or income for a single year.

Figure 6.11-1. Cash Flow Diagram for Life-Cycle Costs When dealing with money or finances for a project over a long period, the time value of money must be considered. The value of money changes over time due to inflation and interest rates. Inflation decreases the value of money over time by increasing the cost of goods and services. Interest accrued over time increases the amount of money. Inflation and interest rates are combined to determine the present worth of an item. First, we assume that the price of the item purchased today is known. Second, an inflation rate is used to determine the future cost. The interest rate is used to determine how much money would have to be set aside today to pay for the item in the future. Together, these factors determine the present worth of the item. Figure 6.11-2 shows the simplified cash flow diagram from Figure 6.11-1, but with the effects of inflation.



177

Figure 6.11-2. Cash Flow Diagram for Life-Cycle Costs, with Effects of Inflation The equation for calculating the future cost of an item is:

Future Cost = Present Cost x ( 1 + inflation rate ) t , where t = number of years.

The present worth of a future transaction is:

Present Worth = Future Cost x (1 + interest rate ) - t The salvage/scrap value is the value or cost of an item at the end of the life span. The straight -line method of depreciation is the method that is used to determine the salvage value for this project. This method states that the value of a ship decreases in value at a constant rate until it reaches the end of its life span, at which point in time the value of the item is zero. Hence, when the item is halfway through the life span, the item is worth half of its original price. When the item is 75% through its life, its salvage value is 25% of its original price.

Salvage Value = Cost of Item x (1 - n / Life of Item) where n = the time at which the salvage value is calculated.

The traditional LCC structure is shown in Table 6.11-1 and is composed of acquisition, operation and support costs.



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Table 6.11-1

Traditional Vessel Life-Cycle Cost Breakdown Structure

Acquisition Non-recurring Project Management Research and Development Detailed Design Facilities & Tooling

Procurement Shipbuilder Labor and Material Government Furnished Equipment Operating and Support Manning Direct Manpower Indirect Manpower Fuel Consumables Maintenance Modernization Decommissioning

Total acquisition cost consists of non-recurring and procurement costs. Non-recurring includes the costs of technology, design development and startup costs. Procurement includes the cost of constructing the ship together with all shipbuilder-furnished and government-furnished equipment. Operating and support cost consists of manning, maintenance and mid-life overhaul. Manning includes direct and indirect manpower costs. Maintenance costs include depot, shipyard, organizational, and intermediate repairs, and fuel costs. Modernization includes subsequent technology changes and ship alterations. The annual life-cycle cost of the four baseline designs described in section 3.0 have been calculated in order to illustrate the differences between SLCs and OPVs. The calculations of annual cost have been calculated in dollars assuming U.S. construction, labor, fuel and maintenance costs. It is assessed that the conclusions would have been similar had the calculation been conducted using euros and assuming European construction, labor and support. The annual costs are based on groups of four ships. The costs of a representative U.S. Navy FFG have been generated for comparative purposes. Depreciation costs are based on the acquisition costs provided in section 3.3 over the following service lives:

600-tonne 2000-tonne OPV SLC OPV SLC FFG 25 20 30 25 30

Service life, Years OPVs were assumed to have longer service lives than SLCs, and small ships were assumed to have shorter service lives than larger ships. These service lives are assessed to be consistent with representative practices. Personnel costs were based on the number of accommodations and current U.S. Coast Guard labor costs, which include all benefits and training, plus an allowance of 1.2 for personnel rotation. Fuel oil costs were based on the speed versus power data for each baseline design and the following operational profiles:



179

Ships Annual Operating Hours

Assumed Operational Profile

600 OPV 3000 70% @ Most Economic Speed of 12kn 25% @ 18kn Transit 5% @ Full Power 600 SLC 1500 60% @ Minimum Speed of 16kn 35% @ 24kn Transit 5% @ Full Power 2000 OPV 5040 60% @ Most Economic Speed of 12kn 35% @ 18kn Transit 5% @ Full Power 2000 SLC 2400 60% @ Most Economic Speed of 12kn 35% @ Full Diesel Power Transit 5% @ Full Power 4000 FFG 3000 60% @ Most Economic Speed of 12kn 35% @ Full Diesel Power Transit 5% @ Full Power

The cost of fuel oil was assumed to be 1.25 USD/gallon, without taxes. The annual operating hours and assumed operational profiles represent typical international practice. It should be noted that the annual fuel oil costs do not include the cost of in-port shore-supplied power. Annual consumable/spare part and maintenance costs were based on U.S. Navy data for the 52m Cyclone class littoral patrol craft, modified as follows:

• Repair parts for HM&E: Cost = f(∆/330 x 14.56/ ∆BHP

)

where:

∆ = full load displacement

330 = baseline displacement

56.14 = baseline BHP/displacement

• Personnel-related consumables: Cost = f(accommodations/30)

• Telecommunication spares: Cost = f(Wt Grp 4 – Op. Fluids)/10, where 10 = baseline weight of Wt Grp 4 – Operating Fluids

• Ordnance spares: Cost = f(Wt Grp 7/6) where 6 = baseline weight of Wt Grp 7

• HM&E maintenance: Cost = f(∆/330)

• Electronics maintenance: Cost = f(Wt Grp 4 – Op. Fluids)/10

• Dry docking, ship alterations, and casualties: Cost = f(LOA/51.83)

• Engine overhauls: diesels Cost = f(No. Eng x 536,2/ EngBHP

)

gas turbines $100,000/engine, assuming overhaul every 10 years



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INITIAL CONSTRUCTION COST:

• PROJECT MANAGEMENT• HARDWARE (e.g.Structure,

Propulsion, Elec .Plant.)• START -UP (e.g.

Tooling,Jigs,Fixtures)• ALLOWANCE FOR CHANGES

(e.g., Design, Schedule)• TEST AND TRIALS• INITIAL OUTFIT (onboard

Spares, Repair Parts, Tools, andFuel)

SAILAWAY COST

• DESIGN• DEVELOPMENT • SOFTWARE (e.g

Computer programs,Coding

• TECHNICAL DATA• PUBLICATIONS• SUPPORT EQUIPMENT• TRAINING EQUIPMENT• INITIAL SPARES (Shore

based)• FACILITY

CONSTRUCTION• PROJECT

MANAGEMENT

• OPERATIONSand SUPPORT

PLUS: PLUS:

PROGRAM ACQUISTION COST

LIFE CYCLE COST + INDIRECT MANPOWER

TOTAL OWNERSHIP COST

• COMMONSUPPORT SYSTEMSCOST

• INFRASTURECOST FORPLANNING,MANAGING, OPERATING,ANDEXECUTING

PLUS:

PROGRAM LIFE CYCLE COST

PLUS:

• INDIRECTMANPOWER

Recruiting Acquisition Training Medical

Support

-

:

•

Figure 6.11-3. Ship Total Ownership/Life-Cycle Cost Composition The annual relative costs of the designs are summarized in Table 6.11-2 using the depreciated acquisition cost of the 600-tonne SLC as a value of 1.0. Figure 6.11-3 provides the major components of a ship’s Total Ownership Cost. Figure 6.11-4 provides the distribution of these costs. Figure 6.11-5 provides the annual costs and acquisition costs per tonne of displacement. As shown in Table 6.11-2 and Figure 6.11-4, annual cost predominately consists of acquisition and personnel. For OPVs, personnel represent the largest portion of annual cost, whereas for SLCs, depreciation of acquisition represents the largest category. For OPVs and SLCs, the annual cost of acquisition decreases proportionately as ship size increases, while the cost of personnel and fuel oil, consumables and maintenance tends to increase. As a percentage of total annual cost SLCs have relatively higher fuel oil, consumable and maintenance costs than OPVs.

Table 6.11-2

Summary of Annual Costs

600-Tonne 2000-Tonne 4000-Tonne Category OPV SLC OPV SLC FFG Acquisition 0.308 1.000 0.651 1.777 2.029

Personnel 0.452 0.732 1.334 1.703 3.212

Fuel Oil 0.102 0.124 0.320 0.339 0.459

Consumables 0.057 0.108 0.203 0.349 0.518

Maintenance 0.175 0.152 0.563 0.506 0.769

Total 1.094 2.116 3.071 4.674 6.987



181

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

600 Tonnes 2000 Tonnes 600 Tonnes 2000 Tonnes 4000 Tonnes

OPV SLC FFG

PE

RC

EN

T Acquisition

Personnel

Fuel

Consumables

Maintenance

Figure 6.11-4. Distribution of Annual Costs

0

5

10

15

20

0 1000 2000 3000 4000 5000

FULL LOAD DISPLACEMENT, TONNES

No

rmal

ized

$ x

100

0

LC AVERAGE ANNUAL COST / 0.1T

LC ACQUISITION COST / T

OPV AVERAGE ANNUAL COST / 0.1TOPV ACQUISITION COST / T

Figure 6.11-5. Annual Life-Cycle and Acquisition Cost versus Displacement



182

As shown in Figure 6.11-5, both acquisition and annual costs decrease as displacement increases. As also shown in Figure 6.11-5, the cost of OPVs is much lower than that of SLCs. This data indicates that based on the total number of tones, i.e. the acquisition and total ownership costs of 5 1,000 ton corvettes will be substantially higher than the costs of one 5,000 tonne frigate. Small combatants are therefore relatively expensive. 6.12 Corrosion and Antifouling 6.12.1 Influencing Variables 6.12.1.1 Materials Applied/Combinations of Materials Depending on the selected materials, different protection concepts can be applied. Non-metallic hulls require cathodic protection only for shafts, propellers, etc., but, in certain circumstances, they will have to be secured separately to avoid damage due to osmosis. High-alloyed steels are most commonly susceptible to pit and crevice corrosion and needs to be considered in construction. Sacrificial anodes (Zn or Al) or Impressed Current Corrosion Protection (ICCP) systems can be used as active corrosion prevention systems. Passive corrosion systems prevention most commonly employ a zinc primer and 2k epoxy resin paint. Marine growth is prevented by use of tin-free AF Systems or Fouling-Release Coatings (i.e. silicone based). 6.12.1.2 Lifespan of the Object The corrosion protection system chosen depends on the service life desired for the ship. ICCP systems are uneconomical for smaller ships/boats with a service life of less than 15 years. 6.12.1.3 Overhauling Intervals In order to reduce overhaul costs, it is desired to extend the time-span for dry dockings. Because of this interest, ablative or abrasive AF systems are not well suited for operational periods of more than four years due to their inherent dissipative properties. Fouling-release systems like silicone coatings may provide longer time-spans. The regular replacement of sacrificial anodes can only be avoided by ICCP systems. 6.12.1.4 Relevancy for Signatures The choice for corrosion and antifouling protection may include consideration of ship signature management, depending on the operational purpose of the ship. Active corrosion protection devices have a considerable influence on the electromagnetic signature. Modulation effects of the corrosion currents influence low-frequency electric fields and electromagnetic signatures. Specific sacrificial anodes, multi-zone ICCP systems, or active surfaces can be designed for use where signatures are a concern. 6.12.1.5 Costs Low budgets often evoke economical solutions. It is necessary to determine whether there is a need for a special military approach or if the use of commercial equipment is acceptable. 6.12.1.6 Space and Weight Limitations Because of the variety of different functions that are required, even from smaller ships, space and weight often become a problem. The appropriate choice of the anode material may help. Aluminum, as compared to zinc, will result in about 50% less weight. The active corrosion prevention method (sacrificial anodes, ICCP system) should be evaluated with respect to both weight and space.



183

6.12.1.7 Operational Area The operational area has a considerable influence on the choice of marine growth protection and, to a lesser extent, on the method of corrosion protection. The intensity of fouling in the underwater area depends on the water temperature as well as on the food supply for the great variety of marine life forms. Problems occur not only at the outer hull; seawater pipes are affected also. Special growth protection systems with a biocide impact (chlorine or copper ions) are state-of-the-art. Marine growth is indirectly related to corrosion mechanisms (microbiological-induced corrosion is a current topic of worldwide discussion). 6.12.1.8 Labor Safety and Environmental Protection The constantly changing labor safety and environmental protection laws have to be considered. Exemptions due to military status should only be used in special cases when there is an interference between the system requirements and the material protection. 6.12.1.9 Corrosion-Management in Construction During development, a corrosion management needs to be considered in the design. Unfavorable selection of materials has to be avoided, including materials for the ship hull, shaft, propeller, piping and NBC sprayers. The selection of the parts determines the quality of corrosion protection. Edges must be chamfered and inaccessible corners must be avoided to reduce corrosion problems.



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7.0 CONCLUSIONS AND RECOMMENDATIONS 7.1 Conclusions

The aim of the Specialist Team on Small Ship Design was to produce a Naval Group 6 Working Paper on acceptable criteria, standards and specification templates for small ship design and construction. These acceptable criteria, standards and specification templates are intended to be for the design and construction of small surface littoral combatant ships and offshore patrol vessels with displacements ranging between 600 tonnes and 2000 tonnes. The goals of this effort were to stimulate new thinking in small ship acquisition, evaluate standardized formats for NATO -PfP ship specifications, get and spread new information on technology and materials suitable for small ships and combine the work done in different co-operative working groups to a common base. Both the aim and the goals of the Specialist Team on Small Ship Design have been achieved. In accomplishing this work a number of important findings were reached, including the following:

a. Small littoral combatants and OPVs often are about the same size and operate in similar environments, but are very different. Small littoral combatants are ships designed to operate in a dense, high threat, combat environment within the reach of ground based attack aircraft and shore based anti-ship missiles, whereas OPVs are designed to enforce maritime law and ensure the safety of life at sea. Small littoral combatants generally depart, conduct an operation and return without replenishment, whereas OPVs generally stay at sea for extended periods of time and often replenish at sea. The acquisition cost of SLCs is much higher than OPVs of comparable size. This primarily reflects the higher costs of payload, propulsion and engineering.

b. Personnel cost represent the largest category of life cycle cost for OPVs while for SLCs the cost of acquiring the platform was the largest category contributing to life cycle cost. It was also determined that for both OPVs and SLCs, the cost of acquisition decreases proportionately as ship size increases, while the cost of personnel and fuel oil, consumables and maintenance tends to increase. Both acquisition and operating costs decrease as displacement increases. The life cycle cost of an OPV is much lower than that of a SLC. In addition data indicates that SLCs are expensive relative to typical NATO frigates or large littoral combatants.

c. Small ships with fixed systems and limited capabilities provide little platform flexibility, however the addition of task related equipment modules, manned or unmanned off-board vehicles, and tasked related manning detachments can be used to adapt small ships to the demands of specific missions or tasks and greatly enhance the range of missions and tasks small ship can perform. However for mission modularity to be successful on small ships, the concept of ship reconfigurability needs to be accounted for at the very earliest stages of planning for a ship acquisition and carried through the design and acquisition process. Mission modularity by its very nature means that all of the potential capabilities of the ship will not be available at all times. Careful analysis is necessary to identify what capabilities need to be permanently build into the ship and which capabilities can be moved onto and off the ship so that the ship can be tailored for a specific mission or task.

d. Small ships are manned by small crews, however onboard small ships there is a need for many specialized capabilities which conflicts with the concept of a small crew. There are five proven methods for balancing work load with crew size on small ships: buffering (postponing some work from peak times to less busy times in the day); mechanisation (use machines to perform labour intensive work); automation (install self actuating or self regulating processes into the ship keeping humans out of the loop); architecture (optimize arrangement of the ship, systems and components to lower work load); outsourcing (shift work from the crew to shore). Deciding which strategies are effective and should pursued need to be considered and analyzed in the very earliest stages of ship design. The analysis methods, management



185

concepts and processes for compiling a crew list are the same for both small ships and large ships.

e. The scope of applicability of AMMEP-3 (Shipboard pollution abatement equipment catalogue) is directed mainly towards blue waters navies (and therefore to frigate-type vessels), and the equipments described tend to have significant weight, space and services requirements. It is recommended that the scope of AMMEP-3 be expanded to incorporate technical descriptions and data of smaller equipment, designed to small ship requirements.

f. Many of the current NATO ANEPs and STANAGs are fully or partially applicable to small ships, however many of these same documents are out dated and in need of revision to reflect current technology and thinking.

7.2 Recommendations The Terms of Reference for NATO Naval Group 6, Specialist Team on Small Ship Design established a board set of tasks to be accomplished in a relatively short period of time. All of these tasks have been accomplished; some in greater detail than others, however there are a number of recommendations that have developed as a result of this team’s work:

a. Establish a Specialist Team on Mission Modularity to address mission analysis and systems engineering processes to support decision and design aspects of incorporating modularity into naval ships.

b. Establish a Specialist Team to address launch/recovery of unmanned and manned vehicles c. Establish a Specialist Team to address Survivability and Vulnerability of Small Ships to

Asymmetrical Threats. This team should be open to Partner for Peace Nations. d. Establish a Specialist Team on Composite Materials to address application and design of

composite materials in naval vessels. e. Establish a Specialist Team to update ANEP 52 on Advanced/Alternative Hull Forms to

address developments with multihulls and monohulls since ANEP 52 was published.



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8.0 REFERENCES Chapter 6 6.2.1 Introduction 1. Blount D.L. (1993). Prospects of Hard-Chine, Monohull Vessels, 2nd Intl. Conf. on FAST Sea

Transportation FAST’93, Yokohama, Japan, December 13-16. 2. Blount D.L. (1995). Factors influencing the Selection of a Hard-Chine or Round-Bilge Hull for High

Froude Numbers, 3rd Intl. Conf. on FAST Sea Transportation FAST’95, Travemuende, Germany, September.

3. Kehoe, J.W., Brower, K.S. ad Serter, E.H. (1986). Deep-Vee Hulls. Improved Seakeeping for Small, Fast Warships, Intl. Defence Review, Vol. 19, November.

4. Repetto, R.A. (2001). Overview, Monohulls. An Overview on Advanced Marine Platforms and their Comparison, Transactions of the Schiffbautechnische Gesellschaft e.V., Vol. 95, pp.157-163, Hamburg, Germany.

5. Serter, E.H. (1988). Comparative Studies for New US Frigate Hull, Intl. Defence Review, Vol. 21, No. 2.

6.2.3 Air Chusion Vehicles 1) Igor Andryushchenko: Murena landing boat on air cushion. Military Parade. 1995. 2) Brian G. Forstell –Band, Lavis & Associates, Inc., CDR Pekka Kannari –Finnish Navy: Hyper 01.

Design of the T-2000 Combat Craft. 3) Peter J. Mantle: Air Cushion Craft Development (First Revision). 4) Frank P. Higgins: Model C-7: Ambitious Transportation for the nineties. (HPMW ’92) Intersociety

High Performance Marine Vehicle Conference and Exhibit. 1992. 5) Shirou Ono etc.: Recent development of air cushion vehicles in Japan. (HPMW ’92) Intersociety High

Performance Marine Vehicle Conference and Exhibit. 1992. 6) John Auzins, U.H. Rowley: LCAC: A systems devolution. (HPMW’92) Intersociety High Performance

Marine Vehicle Conference and Exhibit. 1992. 7) David R. Lavis –Band, Lavis & Associates, Inc.: Hovercraft Development. (HPMW’92) Intersociety

High Performance Marine Vehicle Conference and Exhibit. 1992. 8) Joseph R. Amyot: Hovercraft Technology, Economics and Applications, Studies In Mechanical

Engineering, 11 National Research Council of Canada. Elsevier 1989. 9) Report number DTNS RDC-80/12 4727 revised Mantle Eng. Company / David Taylor Naval Ship

Research and Development Center. 1980. 6.2.7 Trimaran 1) Proceedings of RINA International Conference – RV ‘TRITON’: Trimaran Demonstrator Project, April

2000, Southampton (9 papers) 2) van Griethuysen W J, Bucknall R W G, Zhang J W: Trimaran Design – Choices and Variants for

Surface Warship Applications, Warship 2001, London, June 2001 6.4 Standardized Marine Environmental Protection Equipment 1) Lawry, Steven: “Marine Environmental Protection for Small RAN (Royal Australian Navy) Ships”. Presentation to SWG/12 in the April 2003 Meeting. 6.6 Composite Materials and Comparison with Other Materials Used for Naval Shipbuilding 1) Materiali di costruzione navi di superficie – Nuove tendenze e orientamenti – M.Volpone -Fincantieri 2) 14th International Ship and Offshore Structure Congress 2003 – Committee V2 – Structural Design of

High Speed Vessels 3) Progetto definitivo sovrastruttura in composito per 4° unità NUMC – Intermarine



187

4) Selezione delle materie prime e della tecnologia di fabbricazione per i compositi costitituenti l’ unità – Intermarine

5) CFRP Sandwich in the Visby Class Corvette for the Swedish Navy – A. Lonno 6) Continued Development of Swedish Surface Technology – J. Nilsson – Kockums AB 6.10 Manning/Human Factors/Automation/Maintenance Philosophy 1) ANEP 21 – Procedures for ship manning for NATO surface ships 2) ACDC – TNO Physics and electronics laboratory, M.P.W. Gillis, MSc 3) Conceptual design of warships - Ph.A.Wolff, Msc



188

APPENDIX 9.1

600-TONNE OPV SYNTHESIS MODEL OUTPUT



189

600 OPV

CHARACTERISTICS --------------- LENGTH (LOA) 214.50 FEET 65.38 METERS LENGTH (LBP) 200.00 FEET 60.96 METERS BEAM (B) 25.57 FEET 7.79 METERS DRAFT, FULL LOAD (T) 10.27 FEET 3.13 METERS MEAN HULL DEPTH 18.23 FEET 5.56 METERS FREEBOARD AT FP 17.73 FEET 5.41 METERS FREEBOARD AT AP 5.23 FEET 1.60 METERS PRISMATIC COEFFICIENT .6500 CWP .8370 MAXIMUM SECTION AREA COEF. .6750 CIT .0606000 BLOCK COEFFICIENT .4387 COMPLEMENT 30. DISPLACEMENT: MOLDED 658.19 L.T. 668.75 METRIC TONS APPENDAGE 13.21 L.T. 13.43 METRIC TONS DOME .00 L.T. .00 METRIC TONS FULL LOAD 671.41 L.T. 682.18 METRIC TONS CUBIC NUMBER/100000 .932 CU.FT. .0264 CUBIC METERS TOTAL ENCLOSED VOLUME 101112.50 CU.FT. 2863.19 CUBIC METERS BODY PLAN: GERTLER WORM: SEMI-DISPLACEMENT, ROUND BILGE HIGH SPEED SERIES WORM: PCOEF (=EHP/SHP): FULL LOAD MEAN TRIAL MIN. OP. DRAFT, FEET 10.27 10.02 9.78 DISPL, LONG TONS 671.41 640.33 609.20 DISPL/(.01*LBP)**3 83.9256 80.0411 76.1498 GM/BEAM .0841 .0848 .0850 TRIAL SPEED, KNOTS 20.75 21.10 SUSTAINED SPEED, KNOTS 19.55 19.80 DIESEL PROPULSION PLANT (2 PROPS, DIA= 5.55 FT., RPM= 600.00) WITH 4.50 L.T. ADDED FOR CONTR. PITCH PROPS TWO MEDIUM SPEED DIESELS 3500.00 HP EACH ENDURANCE (OPERATING PROFILE): STORES & PROVISIONS = 7.00 DAYS SPEED FULL LOAD MEAN TRIAL LOAD FUEL OIL KNOTS DIST. NM DAYS DIST. NM DAYS LONG TONS 16.00 2821.35 7.35 2999.32 7.81 90.49 ENCLOSED DECK AREA (SQFT.): AVAILABLE = 7152.76 REQUIRED = 6930.09 AVAILABLE LESS REQUIRED = 222.66 OPEN WEATHER DECK AREAS: 1153.24 SQFT. FWD OF STATION 4.550 1745.49 SQFT. AFT OF STATION 14.300 600 OPV



190

WEIGHT AND KG SUMMARY --------------------- VERTICAL WEIGHT KG MOMENT LIGHT SHIP WEIGHT GROUP: (L.T.) (FT.) (FT.TONS) 1 - HULL STRUCTURE 259.23 13.26 3436.49 2 - PROPULSION PLANT 66.30 7.75 513.95 3 - ELECTRIC PLANT 28.54 13.86 395.53 4 - COMMAND & SURVEILLANCE 11.64 36.13 420.40 5 - AUXILIARY SYSTEMS 77.81 13.32 1036.44 6 - OUTFIT / FURNISHINGS 49.98 18.27 913.01 7 - ARMAMENT 4.60 29.12 133.95 --------- --------- --------- LIGHT SHIP SUM WT. GRS. (1-7) 498.09 13.75 6849.77 L.S. WT. MARGIN 8.000%(1-7) 39.85 L.S. KG MARGIN 4.000%KG(1-7) .55 --------- --------- --------- TOTAL LIGHT SHIP 537.94 14.30 7693.66 FIXED LOADS: WFL1 - CREW AND EFFECTS 3.54 23.97 84.77 WFL2 - STORES AND PROVISIONS 1.13 13.38 15.05 WFL3 - POTABLE WATER 13.37 13.38 178.88 WFL4 - DIESEL OIL .00 .00 .00 WFL5 - LUBE OIL 2.69 2.01 5.39 WFL6 - INPUT LOADS 13.23 12.00 158.76 WFL7 - AMMUNITION 1.69 14.65 24.75 WFL8 - AVIATION AND REL.LOADS 7.34 28.83 211.61 --------- --------- --------- TOTAL FIXED LOADS 42.98 15.80 679.21 ENDURANCE FUEL OIL 90.49 8.10 732.71 FULL LOAD DISPLACEMENT 671.41 13.56 9105.58 FINAL SHIP: ----------- FULL LOAD DISPLACEMENT 671.41 LONG TONS KG - FULL LOAD 13.56 FEET



191

600 OPV

INTACT STABILITY SUMMARY: -------------------------

MIN OP LOAD MEAN TRIAL LOAD FULL LOAD FIXED WEIGHT KG WEIGHT KG WEIGHT KG

LOADS (L.T.) (FT.) (L.T.) (FT.) (L.T.) (FT.) ----- ---------------- ---------------- ---------------- WFL1-CREW 3.54 23.97 3.54 23.97 3.54 23.97 WFL2-STRS .37 20.83 .75 17.05 1.13 13.38 WFL3-P.W. 8.96 12.26 11.10 12.80 13.37 13.38 WFL5-L.O. .89 2.01 1.80 2.01 2.69 2.01 WFL6-JP-5 4.37 7.31 8.86 9.69 13.23 12.00 WFL7-AMMO .56 14.65 1.13 14.65 1.69 14.65 WFL8-AVIATION 7.34 28.83 7.34 28.83 7.34 28.83 ------- ------ ------- ------ ------- ------ NON-FUEL LOADS 26.02 17.52 34.52 16.15 42.98 15.80

FUEL OIL LOAD 45.24 10.35 67.87 9.22 90.49 8.10 LIGHT SHIP WT. 537.94 14.30 537.94 14.30 537.94 14.30 ------- ------ ------- ------ ------- ------ TOTAL DISPL. 609.20 14.15 640.33 13.86 671.41 13.56

DRAFT, FEET 9.78 10.02 10.27

KB 6.84 7.02 7.19 + BMT 9.67 9.25 8.80 ----- ------- ------- ------- KMT 16.51 16.26 15.98 - KG 14.15 13.86 13.56 ----- ------- ------- ------- GMT 2.36 2.40 2.42 - FS CORR .19 .23 .27 ----- ------- ------- ------- GMT, FEET 2.17 2.17 2.15

GMT/B .0850 .0848 .0841



192

600 OPV ENCLOSED DECK AREA ------------------ AREAS IN SQUARE FEET AVAILABLE: FIXED WIDTH SUPERSTRUCTURE STACK 240.00 VARIABLE WIDTH SUPERSTRUCTURE MN.DK.,75.5-160.5 1459.05 01 LVL,75.5-143 1158.66 02 LVL,60.5-75.5 257.48 01 LVL,28-45 300.39 01 LVL,45.5-75.5 514.96 BRIDGE 332.42 TOTAL DECK AREA IN SUPERSTRUCTURE 4262.96 DECKS AND PLATFORMS IN HULL HT-FWD XL-FWD HT-AFT XL-AFT 18.50 .00 15.00 45.50 1014.56 15.00 45.50 15.00 75.50 807.93 6.50 143.00 6.50 160.50 400.96 9.31 10.50 7.00 45.50 306.62 7.00 45.50 7.00 68.00 359.73 TOTAL DECK AND PLATFORM AREA IN HULL 2889.79 ---------- TOTAL AVAILABLE DECK AREA 7152.76 REQUIRED: AREA CLASSIFICATION 1.1 COMMUNICATION/DETECT/EVAL 750.00 1.2 WEAPONS 450.00 1.3 AVIATION 50.00 1 MILITARY MISSION PERFORMANCE 1250.00 2 SHIP PERSONNEL 3107.01 3.1 CONTROL 100.00 3.2 MN. PROPULSION SYSTEM 400.00 3.3 AUX. SYSTEMS & EQUIPMENT 630.52 3.4 MAINTENANCE 154.36 3.5 STOWAGE 275.38 3.6 WING & DEEP TANKS .00 3.7 PASSAGEWAYS & ACCESS 715.28 3.8 UNASSIGNED 297.55 3 SHIP OPERATION 2573.08 ---------- TOTAL REQUIRED DECK AREA 6930.09 AVAILABLE LESS REQUIRED DECK AREA 222.66 3.21 % REQUIRED AREA OPEN WEATHER DECK AREAS: 1153.24 SQFT. FWD OF STATION 4.550 1745.49 SQFT. AFT OF STATION 14.300



193

600 OPV

TABLE OF OFFSETS ---------------- WL STA. 0 2 4 6 8 10 .00 .00 .00 .00 1.35 .00 .00 1.00 .00 .00 .00 4.19 3.78 1.00 2.00 .00 .00 2.85 7.04 7.29 5.90 4.00 .00 1.74 7.28 11.67 14.32 14.97 6.00 .00 3.87 10.11 15.69 19.16 20.49 8.00 .00 6.08 12.94 18.45 22.47 24.46 10.00 .00 8.31 15.77 21.33 24.79 26.67 12.00 1.76 11.12 19.39 23.59 25.29 26.20 14.00 5.56 15.60 22.62 25.89 27.37 27.95 16.00 11.88 21.80 26.34 28.12 28.66 28.67 18.00 15.79 24.78 28.50 30.18 29.81 29.16 20.00 18.87 27.77 30.65 32.23 30.97 29.64 22.00 21.95 30.75 32.81 34.29 32.12 30.13 24.00 25.03 33.73 34.97 36.34 33.28 30.62 WL STA.12 14 16 18 20 .00 .00 .00 .00 .00 .00 1.00 .00 .00 .00 .00 .00 2.00 .00 .00 .00 .00 .00 4.00 12.87 5.52 .00 .00 .00 6.00 21.48 20.82 23.09 .00 .00 8.00 25.46 25.48 25.89 23.96 22.77 10.00 27.79 28.29 28.24 27.70 27.12 12.00 27.29 27.26 27.05 26.82 26.37 14.00 28.17 28.04 27.99 27.82 27.51 16.00 29.06 28.83 28.93 28.82 28.65 18.00 29.95 29.61 29.87 29.81 29.78 20.00 30.83 30.39 30.81 30.81 30.92 22.00 31.72 31.17 31.74 31.80 32.06 24.00 32.60 31.95 32.68 32.80 33.20



194

600 OPV DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) SHELL & LONGL.FRMG. 111,114,116 78.99 7.92 TRANSVERSE FRAMING 115,117 19.91 7.84 FOCSLE DECK 136 11.03 18.02 MAIN DECK 131 34.96 18.02 PLATFORMS & INNER BOTTOM 141-9,113 7.45 6.47 STRUCTURAL BULKHEADS 121-3 27.05 8.22 MISCL. STRUCTURE 161,163,167-9 9.89 8.57 ALUM. SUPERSTRUCTURE 151-9,162 17.15 34.41 STEEL SUPERSTRUCTURE 20.15 21.20 GR2 FOUNDATIONS 182 4.97 3.19 GR3-7 FOUNDATIONS 183-7 7.77 11.59 MASTS 171 .07 54.00 INPUT GR1 7.80 24.75 FREE FLOODING LIQUIDS 198 .91 2.37 WELDING & MILL TOLERANCE 11.12 13.29 SUM GP1 259.23 13.26 PROPULSION ENGINES 233,234 18.44 8.00 REDUCTION GEARS 241,242 7.00 6.00 2 SHAFT(S) 243 3.09 4.00 SHAFT BEARINGS 244 .93 4.00 PROPS 245 (DIA= 5.55 FT., 600.00RPM-FP) 6.89 6.25 INTAKES & EXHAUSTS 251,259 4.46 19.14 PROPULSION CONTROL 252 2.00 12.40 COOLING WATER SYSTEM 256 7.60 6.36 FUEL OIL SYSTEM 261 3.98 8.53 LUBE OIL SYSTEM 262,264 7.00 5.50 OPERATING FLUIDS & REPAIR PARTS 298,299 4.91 7.00 SUM GP2 66.30 7.75 GENERATORS 311-3,342 18.77 10.50 SWITCHBOARDS 324 1.50 20.40 CABLE 321-3 3.32 16.22 LIGHTING 331-2 3.64 28.22 REPAIR PARTS 399 .54 10.00 OPERATING FLUIDS 398 .77 7.65 SUM GP3 28.54 13.86 COMMAND & SURVEILLANCE (GR4 INPUTS) 8.13 42.10 INTERIOR COMMUNICATION 431-9 3.22 20.73 REPAIR PARTS & OPERATING FLUIDS 498-9 .28 40.00 SUM GP4 11.64 36.13



195

600 OPV DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) HEATING, VENTILATION, & AIR COND. 511-4 11.00 16.41 FIREMAINS, FLUSH SYSTEM 521,522,524 7.95 13.49 STEERING, RUDDERS 561,562 8.32 8.02 SCUPPERS, PLUMBING, DRAINS 526,528,529 5.25 9.84 FUEL OIL SYSTEMS 541 4.11 8.39 FIRE EXTINGUISHING SYSTEMS 555 3.05 13.12 ANCHOR HANDLING, MOORING, ETC. 581,582 10.72 16.22 DISTILLING & POTABLE WATER SYS. 531,533 2.83 11.12 ENVIRONMENTAL CONTROL SYSTEMS 593 1.12 6.38 BOATS AND BOAT HANDLING 583 8.00 16.63 AVIATION SUPPORT SYSTEMS 588 3.25 25.92 OPERATING FLUIDS 598 5.73 10.94 REPAIR PARTS 599 .50 10.00 JP-5 SYSTEM 1.50 10.50 BOW THRUSTER 4.50 9.50 SUM GP5 77.81 13.32 HULL FITTINGS 611,612,625,633 3.04 21.33 RIGGING & CANVAS 613 .25 28.00 LADDERS & GRATINGS 622,623 3.03 25.70 NON-STRUCTURAL BULKHEADS 621,624 10.72 20.24 PAINTING 631 5.95 12.03 DECK COVERING 634 2.67 15.66 INSULATION 635,637 8.69 16.77 SUPPORT FURNISHING 652,654-672 7.23 12.15 PERSONNEL RELATED FURNISHING 641-651 8.40 23.72 SUM GP6 49.98 18.27 WEAPONS, ARMAMENTS (GR7 INPUTS) 4.60 29.12 SUM GR(1-7) 498.09 13.75



196

600 OPV ELECTRIC PLANT LOAD ANALYSIS ---------------------------- ELECTRIC LOAD: SUMMER, READINESS CONDITION ONE ITEM KW (EST.) STEERING GEAR 7.70 CONTR. PITCH PROP. 5.45 PROPULSION CONTROL 7.69 PROPUL. AUX. EQUIP 1.60 DECK MACHINERY .00 SHOP EQUIPMENT .67 INTERNAL COMMUNIC. .60 DEGAUSSING .00 LIGHTING 13.25 HOTEL EQUIPMENT 9.75 HVAC 81.68 FIRE PUMPS 3.55 AUX. MACHY. EQUIP. 41.93 FIN STABILISERS .00 JP-5 SYSTEM 1.50 MISCL. & INPUT .00 PAYLOAD 36.30 SUBTOTAL 211.68 DESIGN & CONSTRUCTION MARGIN ( 15.00% ) 31.75 ---------- SUBTOTAL 243.43 SERVICE LIFE CAPACITY MARGIN ( 15.00% ) 36.52 ---------- TOTAL MAXIMUM FUNCTIONAL LOAD 279.95 REQUIRED CAPACITY FOR 1 GENERATOR(S) WITH LOAD MARGIN = 1.00000 279.95 1 GENERATORS CARRYING LOAD 2 GENERATORS INSTALLED 300. KW RATING PER GENERATOR ESTIMATED EMERGENCY GENERATOR LOAD 106. KW 1 EMERGENCY GENERATORS OF 160. KW EACH



197

600 OPV PAGE 9 SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- HULL FORM PARAMETERS: LBP 200.00 FT. CP .650 1000*CV 2.880 B 25.57 FT. CX .675 D-L RATIO 82.27 T 10.27 FT. B/T 2.491 DISP-MLD 658.19 L.T. DCF .00030 APCOR .00000 CAIR 1.00000 NPROP 2 UMECH .96500 EHP MARGIN 8.00% INF/SUP SEMI-DISP, ROUND BILGE FOR VLR GREATER THAN 1.400 : INF/SUP SEMI-DISP, ROUND BILGE WETTED SURFACE: SHIP/GERTLER 1.1168 AREA WS 6126.62 SQFT.

VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 12.00 .849 438 0 100 13 44 595 .600 1027 12.00 14.00 .990 816 0 158 20 80 1074 .600 1855 14.00 16.00 1.131 1201 0 237 30 117 1585 .600 2738 16.00 18.00 1.273 1741 0 337 43 170 2291 .600 3956 18.00 20.00 1.414 2760 0 462 59 262 3543 .600 6119 20.00 22.00 1.556 3883 0 615 78 366 4942 .600 8535 22.00 24.00 1.697 4929 0 798 102 466 6295 .600 10873 24.00

INSTALLED POWER: 7000.00 HP 5219.90 KW SPEED: TRIAL 20.75 KNOTS AT INSTALLED POWER SUSTAINED 19.55 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 16.00 2821.35 7.35 2737.73 .39988 90.49 TOTAL 2821.35 7.35 90.49 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 90.49 L.T.



198

600 OPV

SPEED-POWER ESTIMATE FOR FULL LOAD ----------------------------------

DETAILS OF BARE HULL EHP ESTIMATE

VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 12.00 .849 .840 3.564 246.88 1.775 191.14 438.02 12.00 14.00 .990 2.094 1.888 517.80 1.739 298.26 816.06 14.00 16.00 1.131 2.533 1.540 762.43 1.709 438.59 1201.02 16.00 18.00 1.273 3.347 1.207 1124.78 1.683 616.37 1741.15 18.00 20.00 1.414 5.332 .945 1923.89 1.660 835.76 2759.65 20.00 22.00 1.556 6.328 .865 2781.67 1.640 1100.90 3882.57 22.00 24.00 1.697 6.534 .815 3513.43 1.622 1415.88 4929.31 24.00

KEY TO ABBREVIATIONS: VK SPEED IN KNOTS VLR VK/SQRT(LBP) WORM WORM CURVE (INF/SUP = CR-SHIP/CR-GERTLER) *CR 1000.0*CR EHPR RESIDUARY RESISTANCE EHP (FORM DRAG EHP) *CF 1000.0*CF EHPF FRICTIONAL RESISTANCE EHP (INCL. CFRICT) EHPBH EHPR+EHPF (BARE HULL EHP) EHPDM DOME DRAG EHP EHPAPP APPENDAGE DRAG EHP (EXCLUDING DOMES) EHPAIR STILL AIR DRAG EHP EHPMAG EHP MARGIN EHPT TOTAL EHP (BRITISH HP = 550 FT.LB./SEC.) PC PROPULSIVE COEFFICIENT = EHPT/SHP UMECH=SHP/BHP HP TOTAL HORSE POWER INCLUDING THE EFFECTS OF PC & UMECH HP=SHAFT HORSE POWER (SHP) IF UMECH=1.00 HP=BRAKE HORSE POWER (BHP) IF UMECH<1.00



199

600 OPV

SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ----------------------------------------

HULL FORM PARAMETERS: LBP 200.00 FT. CP .643 1000*CV 2.747 B 25.34 FT. CX .673 D-L RATIO 78.49 T 10.02 FT. B/T 2.529 DISP-MLD 627.96 L.T. DCF .00030 APCOR .00000 CAIR 1.00000 NPROP 2 UMECH .96500 EHP MARGIN 8.00% INF/SUP SEMI-DISP, ROUND BILGE FOR VLR GREATER THAN 1.400 : SEMI-DISP, ROUND BILGE WETTED SURFACE: SHIP/GERTLER 1.1168 AREA WS 5982.98 SQFT.

VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 12.00 .849 413 0 97 13 42 565 .600 975 12.00 14.00 .990 758 0 155 20 75 1008 .600 1740 14.00 16.00 1.131 1107 0 231 30 109 1478 .600 2552 16.00 18.00 1.273 1642 0 329 43 161 2175 .600 3756 18.00 20.00 1.414 2602 0 451 59 249 3361 .600 5805 20.00 22.00 1.556 3649 0 600 79 346 4674 .600 8073 22.00 24.00 1.697 4646 0 779 103 442 5970 .600 10311 24.00

INSTALLED POWER: 7000.00 HP 5219.90 KW

SPEED: TRIAL 21.10 KNOTS AT INSTALLED POWER SUSTAINED 19.80 KNOTS AT 80.00% POWER

RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 16.00 2999.32 7.81 2552.13 .40351 90.49 TOTAL 2999.32 7.81 90.49 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 90.49 L.T.



200

600 OPV

SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ----------------------------------------

DETAILS OF BARE HULL EHP ESTIMATE

VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 12.00 .849 .787 3.564 226.03 1.775 186.66 412.69 12.00 14.00 .990 1.933 1.888 466.69 1.739 291.26 757.95 14.00 16.00 1.131 2.309 1.540 678.64 1.709 428.31 1106.94 16.00 18.00 1.273 3.168 1.207 1039.85 1.683 601.92 1641.77 18.00 20.00 1.414 5.069 .945 1786.06 1.660 816.17 2602.23 20.00 22.00 1.556 5.996 .865 2573.91 1.640 1075.09 3649.79 22.00 24.00 1.697 6.214 .815 3263.03 1.622 1382.69 4645.72 24.00



201

APPENDIX 9.2

2000-TONNE OPV SYNTHESIS MODEL OUTPUT



202

2000 OPV CHARACTERISTIC --------------- LENGTH (LOA) 267.92 FEET 81.66 METERS LENGTH (LBP) 250.92 FEET 76.48 METERS BEAM (B) 45.32 FEET 13.81 METERS DRAFT, FULL LOAD (T) 14.80 FEET 4.51 METERS MEAN HULL DEPTH 35.69 FEET 10.88 METERS FREEBOARD AT FP 18.70 FEET 5.70 METERS FREEBOARD AT AP 14.70 FEET 4.48 METERS PRISMATIC COEFFICIENT .6190 CWP .7910 MAXIMUM SECTION AREA COEF. .7600 CIT .0528000 BLOCK COEFFICIENT .4704 COMPLEMENT 88. DISPLACEMENT: MOLDED 2262.82 L.T. 2299.13 METRIC TONS APPENDAGE 21.04 L.T. 21.38 METRIC TONS DOME .00 L.T. .00 METRIC TONS FULL LOAD 2283.86 L.T. 2320.51 METRIC TONS CUBIC NUMBER/100000 4.058 .1149 TOTAL ENCLOSED VOLUME 336763.10 CU.FT. 9536.07 CUBIC METERS BODY PLAN: 20 KN CUTTER GERTLER WORM: 270FT WMEC PCOEF (=EHP/SHP): 270FT WHEC FULL LOAD MEAN TRIAL MIN. OP. DRAFT, FEET 14.80 14.55 14.30 DISPL, LONG TONS 2283.86 2222.37 2160.20 DISPL/(.01*LBP)**3 144.5652 140.6728 136.7379 GM/BEAM .0855 .0881 .0889 TRIAL SPEED, KNOTS 20.20 20.40 SUSTAINED SPEED, KNOTS 19.40 19.53 DIESEL PROPULSION PLANT (2 PROPS, DIA= 9.95 FT., RPM= 265.00) WITH 10.54 L.T. ADDED FOR CONTR. PITCH PROPS FOUR MEDIUM SPEED DIESELS 3000.00 HP EACH, TWO PER SHAFT ENDURANCE (OPERATING PROFILE): STORES & PROVISIONS = 30.00 DAYS SPEED FULL LOAD MEAN TRIAL LOAD FUEL OIL KNOTS DIST. NM DAYS DIST. NM DAYS LONG TONS 12.00 6940.63 24.10 7000.32 24.31 270.66 ENCLOSED DECK AREA (SQFT.): AVAILABLE = 24325.83 REQUIRED = 24390.36 AVAILABLE LESS REQUIRED = -64.53 OPEN WEATHER DECK AREAS: 1908.52 SQFT. FWD OF STATION 4.982 3736.64 SQFT. AFT OF STATION 13.351



203

2000 OPV WEIGHT AND KG SUMMARY --------------------- VERTICAL WEIGHT KG MOMENT LIGHT SHIP WEIGHT GROUP: (L.T.) (FT.) (FT.TONS) 1 - HULL STRUCTURE 852.01 21.42 18250.06 2 - PROPULSION PLANT 185.14 12.55 2324.21 3 - ELECTRIC PLANT 90.73 16.44 1491.62 4 - COMMAND & SURVEILLANCE 32.55 46.36 1508.99 5 - AUXILIARY SYSTEMS 280.25 25.26 7078.85 6 - OUTFIT / FURNISHINGS 245.88 24.12 5930.34 7 - ARMAMENT 6.85 28.59 195.82 --------- --------- --------- LIGHT SHIP SUM WT. GRS. (1-7) 1693.40 21.72 36779.89 L.S. WT. MARGIN 8.000%(1-7) 135.47 L.S. KG MARGIN 4.000%KG(1-7) .87 --------- --------- --------- TOTAL LIGHT SHIP 1828.88 22.59 41311.18 FIXED LOADS: WFL1 - CREW AND EFFECTS 10.37 28.84 299.07 WFL2 - STORES AND PROVISIONS 14.14 17.33 245.04 WFL3 - POTABLE WATER 71.92 17.33 1246.05 WFL5 - LUBE OIL 9.14 10.35 94.55 WFL6 - INPUT LOADS 66.15 15.69 1037.89 WFL7 - AMMUNITION 1.84 24.76 45.55 WFL8 - AVIATION AND REL.LOADS 10.76 43.41 467.15 --------- --------- --------- TOTAL FIXED LOADS 184.33 18.64 3435.39 ENDURANCE FUEL OIL 270.66 9.41 2547.11 FULL LOAD DISPLACEMENT 2283.86 20.71 47293.68 FINAL SHIP: ----------- FULL LOAD DISPLACEMENT 2283.86 LONG TONS KG - FULL LOAD 20.71 FEET



204

2000 OPV INTACT STABILITY SUMMARY: ------------------------- MIN OP LOAD MEAN TRIAL LOAD FULL LOAD FIXED WEIGHT KG WEIGHT KG WEIGHT KG LOADS (L.T.) (FT.) (L.T.) (FT.) (L.T.) (FT.) ----- ---------------- ---------------- ---------------- WFL1-CREW & EFFECTS 10.37 28.84 10.37 28.84 10.37 28.84 WFL2-STRS & PROV 4.67 24.03 9.48 20.63 14.14 17.33 WFL3-P.W. 48.18 15.73 59.69 16.51 71.92 17.33 WFL4-S.W.BALLAST 145.51 9.62 72.75 9.62 .01 9.62 WFL5-L.O. 3.01 8.96 6.12 9.67 9.14 10.35 WFL6-JP-5 22.03 11.23 44.12 13.46 66.15 15.69 WFL7-AMMO .61 24.76 1.23 24.76 1.84 24.76 WFL8-AVIATION 7.63 43.41 9.20 43.41 10.76 43.41 ------- ------ ------- ------ ------- ------ NON-FUEL LOADS 242.01 13.18 212.96 15.32 184.33 18.64 FUEL OIL LOAD 89.32 9.14 180.53 9.28 270.66 9.41 LIGHT SHIP WT. 1828.88 22.59 1828.88 22.59 1828.88 22.59 ------- ------ ------- ------ ------- ------ TOTAL DISPL. 2160.20 20.98 2222.37 20.81 2283.86 20.71 DRAFT, FEET 14.30 14.55 14.80 KB 9.11 9.27 9.43 + BMT 16.28 15.93 15.57 ----- ------- ------- ------- KMT 25.39 25.20 25.00 - KG 20.98 20.81 20.71 ----- ------- ------- ------- GMT 4.41 4.39 4.29 - FS CORR .38 .40 .42 ----- ------- ------- ------- GMT, FEET 4.03 3.99 3.87 GMT/B .0889 .0881 .0855



205

2000 OPV ENCLOSED DECK AREA ------------------ AREAS IN SQUARE FEET AVAILABLE: FIXED WIDTH SUPERSTRUCTURE PORT STACK 90.00 STBD STACK 90.00 01 LVL,62.5-115 1260.00 01 LVL,115-145 720.00 02 LVL,77.5-115 900.00 01 LVL HNGR 660.00 VARIABLE WIDTH SUPERSTRUCTURE 01 LEV P/S HANGAR 443.88 BRIDGE 561.45 TOTAL DECK AREA IN SUPERSTRUCTURE 4725.32 DECKS AND PLATFORMS IN HULL HT-FWD XL-FWD HT-AFT XL-AFT 32.50 .00 29.50 40.00 751.83 29.50 40.00 29.50 190.00 6454.85 22.69 17.50 21.00 40.00 457.24 21.00 40.00 21.00 250.92 8784.57 14.19 17.50 12.50 40.00 348.06 12.50 40.00 12.50 92.50 1649.62 12.50 207.50 12.50 225.00 614.80 3.50 62.50 3.50 92.50 539.53 TOTAL DECK AND PLATFORM AREA IN HULL 19600.50 ---------- TOTAL AVAILABLE DECK AREA 24325.83 REQUIRED: AREA CLASSIFICATION 1.1 COMMUNICATION/DETECT/EVAL 1416.50 1.2 WEAPONS 1329.84 1.3 AVIATION 868.80 1 MILITARY MISSION PERFORMANCE 3615.14 2 SHIP PERSONNEL 10517.76 3.1 CONTROL 150.00 3.2 MN. PROPULSION SYSTEM 960.00 3.3 AUX. SYSTEMS & EQUIPMENT 2706.01 3.4 MAINTENANCE 200.00 3.5 STOWAGE 1909.55 3.6 WING & DEEPTANKS 323.00 3.7 PASSAGEWAYS & ACCESS 3040.73 3.8 UNASSIGNED 968.17 3 SHIP OPERATION 10257.46 ---------- TOTAL REQUIRED DECK AREA 24390.36 AVAILABLE LESS REQUIRED DECK AREA -64.53 -.26 % REQUIRED AREA OPEN WEATHER DECK AREAS: 1908.52 SQFT. FWD OF STATION 4.982 3736.64 SQFT. AFT OF STATION 13.351



206

2000 OPV TABLE OF OFFSETS ---------------- WL STA. 0 2 4 6 8 10 1.75 .00 2.07 6.59 9.89 14.42 17.72 3.50 .00 4.34 11.04 17.42 23.79 27.07 6.00 .00 7.11 16.25 24.68 31.71 34.88 7.50 .00 8.70 19.25 28.56 35.77 38.95 10.00 .00 10.77 22.87 32.63 39.40 42.08 12.50 .00 12.84 26.08 35.95 42.10 44.26 15.00 .15 15.06 28.66 38.16 43.55 45.32 17.50 1.37 16.44 30.04 39.26 44.10 45.32 20.00 2.00 17.70 31.36 40.12 44.47 45.51 25.00 3.38 19.90 33.83 41.22 44.75 45.91 29.50 5.23 21.90 35.66 42.08 44.87 46.10 WL STA.12 14 16 18 20 1.75 12.06 2.52 2.52 .00 .00 3.50 23.84 9.09 2.81 .00 .00 6.00 33.80 26.28 8.42 3.28 .00 7.50 38.74 34.75 22.20 3.69 .00 10.00 42.08 40.37 33.44 14.55 .00 12.50 44.26 43.91 40.74 31.67 .00 15.00 45.34 45.34 42.19 39.48 26.11 17.50 45.62 45.62 42.74 40.15 32.23 20.00 45.81 45.77 43.17 40.82 35.00 25.00 45.97 45.77 43.73 41.52 36.64 29.50 46.12 45.86 44.14 41.89 37.35



207

2000 OPV DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) SHELL & LONGL.FRMG. 111,114,116 235.74 14.88 TRANSVERSE FRAMING 115,117 48.56 13.56 FOCSLE DECK 136 61.81 33.59 MAIN DECK 131 82.74 33.59 SECOND DECK 132 75.22 19.74 PLATFORMS & INNER BOTTOM 141-9,113 44.61 8.88 STRUCTURAL BULKHEADS 121-3 120.49 17.15 MISCL. STRUCTURE 161,163,167-9 51.34 17.90 ALUM. SUPERSTRUCTURE 151-9,162 38.75 51.19 GR2 FOUNDATIONS 182 15.74 9.28 GR3-7 FOUNDATIONS 183-7 19.69 27.41 SONAR DOME STRUCTURE 165 .00 .00 MASTS 171 4.28 77.00 INPUT GR1 14.78 43.26 FREE FLOODING LIQUIDS 198 5.71 3.93 WELDING & MILL TOLERANCE 32.55 21.54 SUM GP1 852.01 21.42 PROPULSION ENGINES 233,234 44.60 11.77 REDUCTION GEARS 241,242 30.63 10.81 2 SHAFT(S) 243 14.07 8.59 SHAFT BEARINGS 244 4.22 8.59 PROPS 245 (DIA= 9.95 FT., 265.00RPM-FP) 24.35 5.46 INTAKES & EXHAUSTS 251,259 19.70 37.47 PROPULSION CONTROL 252 2.00 16.80 COOLING WATER SYSTEM 256 13.03 8.61 FUEL OIL SYSTEM 261 6.82 11.55 LUBE OIL SYSTEM 262,264 12.00 7.45 OPERATING FLUIDS & REPAIR PARTS 298,299 13.71 9.16 SUM GP2 185.14 12.55 GENERATORS 311-3,342 50.31 7.11 SWITCHBOARDS 324 5.50 15.41 CABLE 321-3 15.29 31.76 LIGHTING 331-2 15.83 33.09 REPAIR PARTS 399 1.74 15.50 OPERATING FLUIDS 398 2.06 6.23 SUM GP3 90.73 16.44 COMMAND & SURVEILLANCE (GR4 INPUTS) 20.57 54.42 INTERIOR COMMUNICATION 431-9 10.73 30.25 DEGAUSSING 475 .00 .00 REPAIR PARTS & OPERATING FLUIDS 498-9 1.25 52.00 SUM GP4 32.55 46.36



208

2000 OPV DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) HEATING, VENTILATION, & AIR COND. 511-4 54.59 32.12 FIREMAINS, FLUSH SYSTEM 521,522,524 17.18 24.03 STEERING, RUDDERS 561,562 25.26 15.70 SCUPPERS, PLUMBING, DRAINS 526,528,529 22.85 19.27 FUEL OIL SYSTEMS 541 20.11 16.42 FIRE EXTINGUISHING SYSTEMS 555 10.09 25.70 ANCHOR HANDLING, MOORING, ETC. 581,582 46.67 31.76 DISTILLING & POTABLE WATER SYS. 531,533 14.97 21.77 ENVIRONMENTAL CONTROL SYSTEMS 593 4.87 12.49 BOATS AND BOAT HANDLING 583 22.48 30.10 AVIATION SUPPORT SYSTEMS 588 3.25 39.92 JP-5 SYSTEM 542 2.50 17.84 OPERATING FLUIDS 598 20.63 21.41 REPAIR PARTS 599 1.80 15.50 BOW THRUSTER 8.50 14.00 HELO HANDLING SYSTEM 4.50 39.50 SUM GP5 280.25 25.26 HULL FITTINGS 611,612,625,633 3.37 42.83 RIGGING & CANVAS 613 .39 46.25 LADDERS & GRATINGS 622,623 58.43 13.20 NON-STRUCTURAL BULKHEADS 621,624 43.48 30.33 PAINTING 631 17.43 23.55 DECK COVERING 634 11.61 26.09 INSULATION 635,637 37.82 32.83 SUPPORT FURNISHING 652,654-672 48.70 20.90 PERSONNEL RELATED FURNISHING 641-651 24.64 28.59 SUM GP6 245.88 24.12 WEAPONS, ARMAMENTS (GR7 INPUTS) 6.85 28.59 SUM GR(1-7) 1693.40 21.72



209

2000 OPV ELECTRIC PLANT LOAD ANALYSIS ---------------------------- ELECTRIC LOAD: SUMMER, READINESS CONDITION ONE ITEM KW (EST.) STEERING GEAR 13.93 CONTR. PITCH PROP. 5.45 PROPULSION CONTROL 10.39 PROPUL. AUX. EQUIP 1.60 DECK MACHINERY 6.00 SHOP EQUIPMENT 2.28 INTERNAL COMMUNIC. 4.41 DEGAUSSING .00 LIGHTING 50.96 HOTEL EQUIPMENT 28.60 HVAC 355.57 FIRE PUMPS 15.46 AUX. MACHY. EQUIP. 182.55 FIN STABILISERS 20.00 JP-5 SYSTEM 2.00 MISCL. & INPUT .00 PAYLOAD 62.80 SUBTOTAL 762.02 DESIGN & CONSTRUCTION MARGIN ( 15.00% ) 114.30 ---------- SUBTOTAL 876.32 SERVICE LIFE CAPACITY MARGIN ( 15.00% ) 131.45 ---------- TOTAL MAXIMUM FUNCTIONAL LOAD 1007.77 REQUIRED CAPACITY FOR 1 GENERATOR(S) WITH LOAD MARGIN = 1.00000 1007.77 1 GENERATORS CARRYING LOAD 2 GENERATORS INSTALLED 1100. KW RATING PER GENERATOR ESTIMATED EMERGENCY GENERATOR LOAD 286. KW 1 EMERGENCY GENERATORS OF 375. KW EACH



210

2000 OPV SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- HULL FORM PARAMETERS: LBP 250.92 FT. CP .619 1000*CV 5.013 B 45.32 FT. CX .760 D-L RATIO 143.23 T 14.80 FT. B/T 3.061 DISP-MLD 2262.82 L.T. DCF .00050 APCOR -.60100 CAIR 1.00000 NPROP 2 UMECH .96547 EHP MARGIN 8.00% INF/SUP 270FT WMEC WETTED SURFACE: SHIP/GERTLER 1.0277 AREA WS 11680.51 SQFT. VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 8.00 .505 139 0 40 9 15 203 .652 323 8.00 9.00 .568 205 0 57 13 22 297 .652 471 9.00 10.00 .631 295 0 78 18 31 422 .652 670 10.00 11.00 .694 415 0 104 24 43 586 .652 932 11.00 12.00 .758 583 0 135 31 60 809 .652 1285 12.00 13.00 .821 771 0 171 40 79 1060 .652 1685 13.00 14.00 .884 1044 0 214 50 105 1412 .652 2243 14.00 15.00 .947 1509 0 263 61 147 1979 .652 3145 15.00 16.00 1.010 2148 0 319 74 203 2744 .650 4375 16.00 17.00 1.073 2842 0 382 89 265 3578 .646 5734 17.00 18.00 1.136 3388 0 454 105 316 4263 .641 6889 18.00 19.00 1.199 4176 0 534 124 387 5221 .633 8536 19.00 20.00 1.262 5457 0 623 145 490 6715 .623 11164 20.00 21.00 1.326 7283 0 721 167 654 8825 .610 14984 21.00 22.00 1.389 9322 0 829 193 828 11172 .579 19383 22.00 INSTALLED POWER: 12000.00 HP 8948.40 KW SPEED: TRIAL .00 KNOTS AT INSTALLED POWER SUSTAINED .00 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 12.00 6940.63 24.10 1284.85 .77699 270.66 TOTAL 6940.63 24.10 270.66 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 270.66 L.T.



211

2000 OPV SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- DETAILS OF BARE HULL EHP ESTIMATE VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 8.00 .505 .551 .661 18.44 1.818 120.62 139.06 8.00 9.00 .568 .557 .874 35.10 1.790 169.63 204.73 9.00 10.00 .631 .572 1.143 64.69 1.765 230.14 294.83 10.00 11.00 .694 .622 1.368 112.05 1.743 303.32 415.37 11.00 12.00 .758 .743 1.520 192.89 1.723 390.29 583.19 12.00 13.00 .821 .863 1.488 278.96 1.705 492.20 771.16 13.00 14.00 .884 1.167 1.370 433.89 1.688 610.17 1044.06 14.00 15.00 .947 1.851 1.236 763.36 1.673 745.31 1508.67 15.00 16.00 1.010 2.678 1.152 1249.43 1.659 898.74 2148.16 16.00 17.00 1.073 3.223 1.131 1770.50 1.646 1071.55 2842.06 17.00 18.00 1.136 3.369 1.093 2123.53 1.634 1264.85 3388.38 18.00 19.00 1.199 4.051 .981 2696.65 1.623 1479.73 4176.39 19.00 20.00 1.262 5.252 .919 3763.28 1.612 1693.49 5456.77 20.00 21.00 1.326 6.762 .873 5331.46 1.602 1951.17 7282.63 21.00 22.00 1.389 8.028 .850 7088.20 1.593 2233.34 9321.54 22.00 KEY TO ABBREVIATIONS: VK SPEED IN KNOTS VLR VK/SQRT(LBP) WORM WORM CURVE (INF/SUP = CR-SHIP/CR-GERTLER) *CR 1000.0*CR EHPR RESIDUARY RESISTANCE EHP (FORM DRAG EHP) *CF 1000.0*CF EHPF FRICTIONAL RESISTANCE EHP (INCL. CFRICT) EHPBH EHPR+EHPF (BARE HULL EHP) EHPDM DOME DRAG EHP EHPAPP APPENDAGE DRAG EHP (EXCLUDING DOMES) EHPAIR STILL AIR DRAG EHP EHPMAG EHP MARGIN EHPT TOTAL EHP (BRITISH HP = 550 FT.LB./SEC.) PC PROPULSIVE COEFFICIENT = EHPT/SHP UMECH=SHP/BHP HP TOTAL HORSE POWER INCLUDING THE EFFECTS OF PC & UMECH HP=SHAFT HORSE POWER (SHP) IF UMECH=1.00 HP=BRAKE HORSE POWER (BHP) IF UMECH<1.00



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2000 OPV SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ---------------------------------------- HULL FORM PARAMETERS: LBP 250.92 FT. CP .616 1000*CV 4.876 B 45.24 FT. CX .757 D-L RATIO 139.32 T 14.55 FT. B/T 3.108 DISP-MLD 2201.03 L.T. DCF .00050 APCOR -.60100 CAIR 1.00000 NPROP 2 UMECH .96547 EHP MARGIN 8.00% INF/SUP 270FT WMEC WETTED SURFACE: SHIP/GERTLER 1.0277 AREA WS 11518.66 SQFT. VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 8.00 .505 137 0 39 9 15 201 .652 319 8.00 9.00 .568 202 0 56 13 22 293 .652 465 9.00 10.00 .631 291 0 77 18 31 417 .652 662 10.00 11.00 .694 409 0 102 24 43 578 .652 918 11.00 12.00 .758 571 0 132 31 59 793 .652 1261 12.00 13.00 .821 757 0 168 40 77 1042 .652 1656 13.00 14.00 .884 1021 0 210 50 102 1383 .652 2197 14.00 15.00 .947 1463 0 258 61 143 1926 .652 3060 15.00 16.00 1.010 2058 0 313 74 196 2642 .650 4212 16.00 17.00 1.073 2706 0 376 89 254 3424 .646 5488 17.00 18.00 1.136 3113 0 446 106 293 3958 .641 6396 18.00 19.00 1.199 4026 0 525 124 374 5050 .633 8257 19.00 20.00 1.263 5176 0 612 145 475 6408 .623 10653 20.00 21.00 1.326 7147 0 709 168 642 8666 .610 14715 21.00 22.00 1.389 8688 0 815 193 776 10472 .597 18168 22.00 INSTALLED POWER: 12000.00 HP 8948.40 KW SPEED: TRIAL 24.00 KNOTS AT INSTALLED POWER SUSTAINED 22.62 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 12.00 7000.32 24.31 1260.53 .78523 270.66 TOTAL 7000.32 24.31 270.66 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 270.66 L.T.



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2000 OPV SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ---------------------------------------- DETAILS OF BARE HULL EHP ESTIMATE VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 8.00 .505 .553 .661 18.27 1.818 118.95 137.22 8.00 9.00 .568 .563 .874 34.96 1.790 167.28 202.24 9.00 10.00 .631 .575 1.143 64.10 1.765 226.95 291.05 10.00 11.00 .694 .619 1.368 109.87 1.743 299.11 408.99 11.00 12.00 .758 .727 1.520 186.22 1.723 384.88 571.11 12.00 13.00 .821 .852 1.488 271.63 1.705 485.38 757.01 13.00 14.00 .884 1.143 1.370 419.06 1.688 601.71 1020.78 14.00 15.00 .947 1.791 1.236 728.37 1.673 734.98 1463.35 15.00 16.00 1.010 2.547 1.152 1171.83 1.659 886.28 2058.12 16.00 17.00 1.073 3.044 1.131 1648.92 1.646 1056.70 2705.63 17.00 18.00 1.136 3.001 1.093 1865.18 1.634 1247.33 3112.51 18.00 19.00 1.199 3.911 .981 2567.02 1.623 1459.23 4026.25 19.00 20.00 1.263 4.860 .919 3482.40 1.612 1693.49 5175.89 20.00 21.00 1.326 6.590 .873 5195.85 1.602 1951.17 7147.02 21.00 22.00 1.389 7.310 .850 6454.25 1.593 2233.34 8687.59 22.00



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APPENDIX 9.3

600-TONNE SLC SYNTHESIS MODEL OUTPUT



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600 LITTORAL COMBAT CHARACTERISTICS --------------- LENGTH (LOA) 212.00 FEET 64.62 METERS LENGTH (LBP) 200.00 FEET 60.96 METERS BEAM (B) 28.56 FEET 8.71 METERS DRAFT, FULL LOAD (T) 10.10 FEET 3.08 METERS MEAN HULL DEPTH 20.01 FEET 6.10 METERS FREEBOARD AT FP 14.40 FEET 4.39 METERS FREEBOARD AT AP 8.40 FEET 2.56 METERS PRISMATIC COEFFICIENT .6870 CWP .8370 MAXIMUM SECTION AREA COEF. .6500 CIT .0606000 BLOCK COEFFICIENT .4465 COMPLEMENT 48. DISPLACEMENT: MOLDED 736.10 L.T. 747.91 METRIC TONS APPENDAGE 14.78 L.T. 15.01 METRIC TONS DOME .00 L.T. .00 METRIC TONS FULL LOAD 750.88 L.T. 762.93 METRIC TONS CUBIC NUMBER/100000 1.143 .0324 TOTAL ENCLOSED VOLUME 123773.80 CU.FT. 3504.88 CUBIC METERS BODY PLAN: SEMI-DISPLACEMENT, Round BILGE GERTLER WORM: " " HIGH SPEED SERIES WORM: " " PCOEF (=EHP/SHP): " " FULL LOAD MEAN TRIAL MIN. OP. DRAFT, FEET 10.10 9.70 9.29 DISPL, LONG TONS 750.88 692.60 633.93 DISPL/(.01*LBP)**3 93.8595 86.5746 79.2412 GM/BEAM .0929 .0959 .0925 TRIAL SPEED, KNOTS 28.43 28.40 SUSTAINED SPEED, KNOTS 26.96 24.00 DIESEL PROPULSION PLANT (4 PROPS, DIA= 6.43 FT., RPM= 600.00) FOUR HIGH SPEED DIESELS 7330.00 HP EACH ENDURANCE (OPERATING PROFILE): STORES & PROVISIONS = 7.00 DAYS SPEED FULL LOAD MEAN TRIAL LOAD FUEL OIL KNOTS DIST. NM DAYS DIST. NM DAYS LONG TONS 15.00 2151.60 5.98 2397.59 6.66 100.28 ENCLOSED DECK AREA (SQFT.): AVAILABLE = 7987.56 REQUIRED = 7868.22 AVAILABLE LESS REQUIRED = 119.34 OPEN WEATHER DECK AREAS: 978.10 SQFT. FWD OF STATION 3.350 2161.18 SQFT. AFT OF STATION 13.850 600 LITTORAL COMBAT



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WEIGHT AND KG SUMMARY --------------------- VERTICAL WEIGHT KG MOMENT LIGHT SHIP WEIGHT GROUP: (L.T.) (FT.) (FT.TONS) 1 - HULL STRUCTURE 186.67 13.90 2595.08 2 - PROPULSION PLANT 123.46 9.70 1197.32 3 - ELECTRIC PLANT 28.72 14.83 425.99 4 - COMMAND & SURVEILLANCE 41.81 33.60 1404.66 5 - AUXILIARY SYSTEMS 76.88 14.38 1105.22 6 - OUTFIT / FURNISHINGS 51.73 18.36 949.65 7 - ARMAMENT 28.41 31.17 885.60 --------- --------- --------- LIGHT SHIP SUM WT. GRS. (1-7) 537.68 15.93 8563.52 L.S. WT. MARGIN 8.000%(1-7) 43.01 L.S. KG MARGIN 4.000%KG(1-7) .64 --------- --------- --------- TOTAL LIGHT SHIP 580.70 16.56 9618.54 FIXED LOADS: WFL1 - CREW AND EFFECTS 5.66 20.64 116.76 WFL2 - STORES AND PROVISIONS 1.80 8.65 15.57 WFL3 - POTABLE WATER 19.61 8.65 169.70 WFL4 - DIESEL OIL .00 .00 .00 WFL5 - LUBE OIL 3.00 2.20 6.61 WFL6 - INPUT LOADS 14.21 6.04 85.83 WFL7 - AMMUNITION 15.12 25.58 386.83 WFL8 - AVIATION AND REL.LOADS 10.50 23.17 243.25 --------- --------- --------- TOTAL FIXED LOADS 69.90 14.66 1024.55 ENDURANCE FUEL OIL 100.28 7.53 754.62 FULL LOAD DISPLACEMENT 750.88 15.18 11397.71 FINAL SHIP: ----------- FULL LOAD DISPLACEMENT 750.88 LONG TONS KG - FULL LOAD 15.18 FEET



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600 LITTORAL COMBAT INTACT STABILITY SUMMARY: ------------------------- MIN OP LOAD MEAN TRIAL LOAD FULL LOAD FIXED WEIGHT KG WEIGHT KG WEIGHT KG LOADS (L.T.) (FT.) (L.T.) (FT.) (L.T.) (FT.) ----- ---------------- ---------------- ---------------- WFL1-CREW & EFFECTS 5.66 20.64 5.66 20.64 5.66 20.64 WFL2-STRS & PROV .59 18.75 1.21 13.63 1.80 8.65 WFL3-P.W. 6.47 4.87 13.14 6.79 19.61 8.65 WFL4-S.W. BALLAST .00 .00 .00 .00 .00 .00 WFL5-L.O. .99 1.91 2.01 2.06 3.00 2.20 WFL6-JP-5 4.69 1.99 9.52 4.05 14.21 6.04 WFL7-AMMO 8.43 25.66 11.77 25.62 15.12 25.58 WFL8-AVIATION 10.50 23.17 10.50 23.17 10.50 23.17 ------- ------ ------- ------ ------- ------ NON-FUEL LOADS 37.33 16.88 53.81 15.05 69.90 14.66 FUEL OIL LOAD 15.90 8.97 58.09 8.25 100.28 7.53 LIGHT SHIP WT. 580.70 16.56 580.70 16.56 580.70 16.56 ------- ------ ------- ------ ------- ------ TOTAL DISPL. 633.93 16.39 692.60 15.75 750.88 15.18 DRAFT, FEET 9.29 9.70 10.10 KB 6.50 6.79 7.07 + BMT 12.69 11.88 10.96 ----- ------- ------- ------- KMT 19.19 18.67 18.03 - KG 16.39 15.75 15.18 ----- ------- ------- ------- GMT 2.80 2.92 2.85 - FS CORR .16 .18 .20 ----- ------- ------- ------- GMT, FEET 2.64 2.74 2.65 GMT/B .0925 .0959 .0929



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600 LITTORAL COMBAT ENCLOSED DECK AREA ------------------ AREAS IN SQUARE FEET AVAILABLE: FIXED WIDTH SUPERSTRUCTURE 02 LEV,51-73.5 252.00 03 LEV,61-71 64.00 MULTI-FUNCTI, 101-138.5 595.00 VARIABLE WIDTH SUPERSTRUCTURE MN.DK.,33.5-51 535.95 MN.DK.,51-73.5 701.56 MN.DK.,73.5-100.5 867.63 MN.DK. P/S,1 553.78 01 LEV,51-73 573.03 BRIDGE,33.5-51 295.03 TOTAL DECK AREA IN SUPERSTRUCTURE 4437.97 DECKS AND PLATFORMS IN HULL HT-FWD XL-FWD HT-AFT XL-AFT 16.00 .00 11.50 51.00 832.38 11.50 51.00 11.50 73.50 572.76 10.00 100.50 10.00 111.50 339.44 10.00 138.50 10.00 191.00 1679.05 3.00 51.00 3.00 63.50 125.94 TOTAL DECK AND PLATFORM AREA IN HULL 3549.58 ---------- TOTAL AVAILABLE DECK AREA 7987.56 REQUIRED: AREA CLASSIFICATION 1.1 COMMUNICATION/DETECT/EVAL 1026.00 1.2 WEAPONS 188.00 1.3 AVIATION 670.00 1 MILITARY MISSION PERFORMANCE 1884.00 2 SHIP PERSONNEL 3515.04 3.1 CONTROL 289.00 3.2 MN. PROPULSION SYSTEM 368.00 3.3 AUX. SYSTEMS & EQUIPMENT 285.00 3.4 MAINTENANCE 60.00 3.5 STOWAGE 299.00 3.6 WING & DEEP TANKS .00 3.7 PASSAGEWAYS & ACCESS 866.65 3.8 UNASSIGNED 301.53 3 SHIP OPERATION 2469.18 ---------- TOTAL REQUIRED DECK AREA 7868.22 AVAILABLE LESS REQUIRED DECK AREA 119.34 1.52 % REQUIRED AREA OPEN WEATHER DECK AREAS: 978.10 SQFT. FWD OF STATION 3.350 2161.18 SQFT. AFT OF STATION 13.850



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600 LITTORAL COMBAT TABLE OF OFFSETS ---------------- WL STA. 0 2 4 6 8 10 1.00 .00 .00 .00 4.82 4.36 1.38 2.00 .00 .00 3.32 8.11 8.42 6.88 3.00 .00 .82 5.99 10.90 12.48 12.17 4.00 .00 2.05 8.38 13.44 16.54 17.36 5.00 .00 3.28 10.02 15.98 20.06 21.23 6.00 .00 4.51 11.65 18.00 21.97 23.52 7.00 .00 5.80 13.29 19.59 23.88 25.81 8.00 .00 7.09 14.92 21.18 25.80 28.11 9.00 .00 8.37 16.55 22.77 27.33 29.48 10.00 .00 9.66 18.19 24.57 28.34 30.49 12.00 1.42 11.85 20.00 27.17 28.95 30.17 14.00 2.91 16.25 23.95 28.70 30.98 31.87 16.00 6.36 18.31 26.50 30.46 32.24 32.94 18.50 11.78 24.40 30.43 32.57 33.48 33.70 WL STA.12 14 16 18 20 1.00 .00 .00 .00 .00 .00 2.00 .00 .00 .00 .00 .00 3.00 7.48 .00 .00 .00 .00 4.00 15.13 7.05 .00 .00 .00 5.00 20.55 17.65 24.80 .00 .00 6.00 24.65 23.93 26.41 .00 .00 7.00 26.95 26.63 28.03 23.91 16.41 8.00 29.24 29.32 29.64 27.74 26.46 9.00 30.92 31.31 31.09 30.48 29.64 10.00 31.73 32.32 32.30 31.69 31.06 12.00 31.77 31.82 31.56 31.25 30.68 14.00 32.57 32.50 32.32 32.07 31.60 16.00 33.22 33.08 33.01 32.80 32.43 18.50 34.03 33.79 33.87 33.71 33.47



220

600 LITTORAL COMBAT DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) SHELL & LONGL.FRMG. 111,114,116 53.30 8.67 TRANSVERSE FRAMING 115,117 18.78 8.60 MAIN DECK 131 27.26 19.77 PLATFORMS & INNER BOTTOM 141-9,113 9.94 11.35 STRUCTURAL BULKHEADS 121-3 16.96 10.11 MISCL. STRUCTURE 161,163,167-9 8.88 9.38 ALUM. SUPERSTRUCTURE 151-9,162 20.96 30.48 GR2 FOUNDATIONS 182 9.26 4.31 GR3-7 FOUNDATIONS 183-7 12.52 14.51 MASTS 171 1.50 67.00 INPUT GR1 .81 43.02 FREE FLOODING LIQUIDS 198 2.00 2.80 WELDING & MILL TOLERANCE 4.50 14.02 SUM GP1 186.67 13.90 PROPULSION ENGINES 233,234 67.11 10.56 REDUCTION GEARS 241,242 10.95 8.88 4 SHAFT(S) 243 11.96 7.78 SHAFT BEARINGS 244 3.59 7.78 PROPS 245 (DIA= 6.43 FT., 600.00RPM-FP) 1.66 .48 INTAKES & EXHAUSTS 251,259 3.59 14.00 OTHER GR2 SYSTEMS 252,256,261,262,264 17.06 9.68 OPERATING FLUIDS & REPAIR PARTS 298,299 7.54 7.20 SUM GP2 123.46 9.70 GENERATORS 311-3,342 16.47 11.52 SWITCHBOARDS 324 2.25 13.68 CABLE 321-3 4.99 17.81 LIGHTING 331-2 4.46 25.14 REPAIR PARTS 399 .21 13.89 OPERATING FLUIDS 398 .34 4.80 SUM GP3 28.72 14.83 COMMAND & SURVEILLANCE (GR4 INPUTS) 32.53 37.93 INTERIOR COMMUNICATION 431-9 3.89 22.17 DEGAUSSING 475 4.57 16.01 REPAIR PARTS & OPERATING FLUIDS 498-9 .82 13.89 SUM GP4 41.81 33.60



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600 LITTORAL COMBAT DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) HEATING, VENTILATION, & AIR COND. 511-4 13.61 18.01 FIREMAINS, FLUSH SYSTEM 521,522,524 8.85 14.68 STEERING, RUDDERS 561,562 8.12 8.80 SCUPPERS, PLUMBING, DRAINS 526,528,529 6.44 10.80 FUEL OIL SYSTEMS 541 4.69 9.20 FIRE EXTINGUISHING SYSTEMS 555 3.67 14.41 ANCHOR HANDLING, MOORING, ETC. 581,582 13.14 17.81 DISTILLING & POTABLE WATER SYS. 531,533 3.57 12.21 ENVIRONMENTAL CONTROL SYSTEMS 593 1.37 7.00 BOATS AND BOAT HANDLING 583 1.50 28.50 AVIATION SUPPORT SYSTEMS 588 3.25 19.42 JP-5 SYSTEM 542 2.50 10.00 OPERATING FLUIDS 598 5.66 12.01 REPAIR PARTS 599 .50 13.89 SUM GP5 76.88 14.38 HULL FITTINGS 611,612,625,633 3.66 24.01 RIGGING & CANVAS 613 .28 26.82 LADDERS & GRATINGS 622,623 4.17 11.21 NON-STRUCTURAL BULKHEADS 621,624 6.91 21.39 PAINTING 631 7.13 13.21 DECK COVERING 634 4.38 17.89 INSULATION 635,637 10.65 18.41 SUPPORT FURNISHING 652,654-672 4.23 19.12 PERSONNEL RELATED FURNISHING 641-651 10.32 20.39 SUM GP6 51.73 18.36 WEAPONS, ARMAMENTS (GR7 INPUTS) 28.41 31.17 SUM GR(1-7) 537.68 15.93



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600 LITTORAL COMBAT ELECTRIC PLANT LOAD ANALYSIS ---------------------------- ELECTRIC LOAD: SUMMER, READINESS CONDITION ONE ITEM KW (EST.) STEERING GEAR 7.57 CONTR. PITCH PROP. .00 PROPULSION CONTROL 7.83 PROPUL. AUX. EQUIP 1.60 DECK MACHINERY .00 SHOP EQUIPMENT .75 INTERNAL COMMUNIC. .71 DEGAUSSING 9.78 LIGHTING 16.11 HOTEL EQUIPMENT 15.60 HVAC 100.15 FIRE PUMPS 4.35 AUX. MACHY. EQUIP. 51.42 FIN STABILISERS .00 JP-5 SYSTEM .75 PAYLOAD 174.50 SUBTOTAL 391.12 DESIGN & CONSTRUCTION MARGIN ( 15.00% ) 58.67 ---------- SUBTOTAL 449.79 SERVICE LIFE CAPACITY MARGIN ( 15.00% ) 67.47 ---------- TOTAL MAXIMUM FUNCTIONAL LOAD 517.26 REQUIRED CAPACITY FOR 2 GENERATOR(S) WITH LOAD MARGIN = 1.00000 517.26 2 GENERATORS CARRYING LOAD 3 GENERATORS INSTALLED 300. KW RATING PER GENERATOR



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600 LITTORAL COMBAT SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- HULL FORM PARAMETERS: LBP 200.00 FT. CP .687 1000*CV 3.220 B 28.56 FT. CX .650 D-L RATIO 92.01 T 10.10 FT. B/T 2.828 DISP-MLD 736.10 L.T. DCF .00030 APCOR .00000 CAIR 1.00000 NPROP 4 UMECH .96500 EHP MARGIN 8.00% INF/SUP SEMI-DISPLACEMENT, ROUND BILGE FOR VLR GREATER THAN 1.400 : INF/SUP=1.00 WETTED SURFACE: SHIP/GERTLER 1.1168 AREA WS 6488.22 SQFT. VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 12.00 .849 559 0 127 22 57 764 .560 1414 12.00 14.00 .990 1090 0 201 35 106 1432 .560 2649 14.00 16.00 1.131 1728 0 300 52 166 2247 .560 4158 16.00 18.00 1.273 2255 0 428 74 221 2977 .560 5509 18.00 20.00 1.414 3069 0 587 101 302 4058 .560 7508 20.00 22.00 1.556 4260 0 781 134 414 5589 .560 10342 22.00 24.00 1.697 5496 0 1014 175 535 7220 .560 13360 24.00 26.00 1.838 6741 0 1289 222 660 8912 .560 16492 26.00 28.00 1.980 8034 0 1610 277 794 10715 .560 19827 28.00 30.00 2.121 9191 0 1980 341 921 12433 .560 23007 30.00 32.00 2.263 10602 0 2403 414 1074 14493 .560 26818 32.00 34.00 2.404 12154 0 2882 496 1243 16775 .560 31041 34.00 36.00 2.546 13456 0 3421 589 1397 18863 .560 34906 36.00 38.00 2.687 14687 0 4024 693 1552 20956 .560 38779 38.00 INSTALLED POWER: 29320.00 HP 21863.92 KW SPEED: TRIAL 33.20 KNOTS AT INSTALLED POWER SUSTAINED 30.25 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 15.00 2151.60 5.98 3423.21 .43567 100.28 TOTAL 2151.60 5.98 100.28 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 100.28 L.T.



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600 LITTORAL COMBAT SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- DETAILS OF BARE HULL EHP ESTIMATE VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 12.00 .849 1.145 3.564 356.48 1.775 202.42 558.90 12.00 14.00 .990 2.955 1.888 773.79 1.739 315.86 1089.65 14.00 16.00 1.131 3.966 1.540 1263.96 1.709 464.48 1728.44 16.00 18.00 1.273 4.503 1.207 1602.58 1.683 652.75 2255.32 18.00 20.00 1.414 5.400 1.000 2183.42 1.660 885.09 3068.51 20.00 22.00 1.556 5.750 1.000 3094.49 1.640 1165.88 4260.37 22.00 24.00 1.697 5.720 1.000 3996.47 1.622 1499.45 5495.92 24.00 26.00 1.838 5.460 1.000 4850.53 1.605 1890.09 6740.62 26.00 28.00 1.980 5.130 1.000 5691.80 1.590 2342.08 8033.88 28.00 30.00 2.121 4.640 1.000 6331.73 1.576 2859.65 9191.38 30.00 32.00 2.263 4.320 1.000 7154.66 1.564 3447.01 10601.67 32.00 34.00 2.404 4.050 1.000 8045.23 1.552 4108.33 12153.56 34.00 36.00 2.546 3.650 1.000 8607.95 1.541 4847.78 13455.73 36.00 38.00 2.687 3.250 1.000 9017.81 1.530 5669.51 14687.32 38.00 KEY TO ABBREVIATIONS: VK SPEED IN KNOTS VLR VK/SQRT(LBP) WORM WORM CURVE (INF/SUP = CR-SHIP/CR-GERTLER) *CR 1000.0*CR EHPR RESIDUARY RESISTANCE EHP (FORM DRAG EHP) *CF 1000.0*CF EHPF FRICTIONAL RESISTANCE EHP (INCL. CFRICT) EHPBH EHPR+EHPF (BARE HULL EHP) EHPDM DOME DRAG EHP EHPAPP APPENDAGE DRAG EHP (EXCLUDING DOMES) EHPAIR STILL AIR DRAG EHP EHPMAG EHP MARGIN EHPT TOTAL EHP (BRITISH HP = 550 FT.LB./SEC.) PC PROPULSIVE COEFFICIENT = EHPT/SHP UMECH=SHP/BHP HP TOTAL HORSE POWER INCLUDING THE EFFECTS OF PC & UMECH HP=SHAFT HORSE POWER (SHP) IF UMECH=1.00 HP=BRAKE HORSE POWER (BHP) IF UMECH<1.00



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600 LITTORAL COMBAT SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ---------------------------------------- HULL FORM PARAMETERS: LBP 200.00 FT. CP .674 1000*CV 2.967 B 28.19 FT. CX .644 D-L RATIO 84.77 T 9.70 FT. B/T 2.907 DISP-MLD 678.18 L.T. DCF .00030 APCOR .00000 CAIR 1.00000 NPROP 4 UMECH .96500 EHP MARGIN 8.00% INF/SUP SEMI DISPLACEMENT, ROUND BILGE FOR VLR GREATER THAN 1.400 : INF/SUP=1.00 WETTED SURFACE: SHIP/GERTLER 1.1168 AREA WS 6224.99 SQFT. VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 12.00 .849 507 0 122 22 52 703 .560 1301 12.00 14.00 .990 949 0 193 35 94 1271 .560 2352 14.00 16.00 1.131 1477 0 288 52 145 1963 .560 3633 16.00 18.00 1.273 1999 0 411 74 199 2682 .560 4964 18.00 20.00 1.414 2564 0 563 102 258 3487 .560 6453 20.00 22.00 1.556 3540 0 750 135 354 4779 .560 8843 22.00 24.00 1.697 4536 0 973 176 455 6140 .560 11362 24.00 26.00 1.838 5529 0 1237 223 559 7548 .560 13967 26.00 28.00 1.980 6643 0 1545 279 677 9144 .560 16921 28.00 30.00 2.121 7549 0 1901 343 783 10576 .560 19572 30.00 32.00 2.263 8758 0 2307 416 918 12399 .560 22944 32.00 34.00 2.404 9773 0 2767 500 1043 14083 .560 26061 34.00 36.00 2.546 10940 0 3285 593 1185 16003 .560 29614 36.00 38.00 2.687 12304 0 3863 697 1349 18213 .560 33703 38.00 INSTALLED POWER: 29320.00 HP 21863.92 KW SPEED: TRIAL 35.75 KNOTS AT INSTALLED POWER SUSTAINED 32.55 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 15.00 2397.59 6.66 2986.01 .44822 100.28 TOTAL 2397.59 6.66 100.28 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 100.28 L.T.



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600 LITTORAL COMBAT SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ---------------------------------------- DETAILS OF BARE HULL EHP ESTIMATE VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 12.00 .849 1.049 3.564 313.27 1.775 194.21 507.48 12.00 14.00 .990 2.570 1.888 645.80 1.739 303.04 948.85 14.00 16.00 1.131 3.373 1.540 1031.59 1.709 445.63 1477.23 16.00 18.00 1.273 4.020 1.207 1372.72 1.683 626.27 1998.98 18.00 20.00 1.414 4.420 1.000 1714.64 1.660 849.18 2563.82 20.00 22.00 1.556 4.690 1.000 2421.61 1.640 1118.58 3540.19 22.00 24.00 1.697 4.620 1.000 3097.17 1.622 1438.61 4535.78 24.00 26.00 1.838 4.360 1.000 3715.95 1.605 1813.41 5529.36 26.00 28.00 1.980 4.130 1.000 4396.31 1.590 2247.07 6643.38 28.00 30.00 2.121 3.670 1.000 4805.14 1.576 2743.64 7548.78 30.00 32.00 2.263 3.430 1.000 5450.61 1.564 3307.16 8757.77 32.00 34.00 2.404 3.060 1.000 5831.79 1.552 3941.66 9773.45 34.00 36.00 2.546 2.780 1.000 6289.25 1.541 4651.11 10940.36 36.00 38.00 2.687 2.580 1.000 6864.09 1.530 5439.49 12303.58 38.00



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APPENDIX 9.4

2000-TONNE SLC SYNTHESIS MODEL OUTPUT



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2000 LITTORAL COMBATANT CHARACTERISTICS --------------- LENGTH (LOA) 328.00 FEET 99.97 METERS LENGTH (LBP) 308.00 FEET 93.88 METERS BEAM (B) 43.42 FEET 13.23 METERS DRAFT, FULL LOAD (T) 12.39 FEET 3.78 METERS MEAN HULL DEPTH 29.76 FEET 9.07 METERS FREEBOARD AT FP 20.11 FEET 6.13 METERS FREEBOARD AT AP 17.11 FEET 5.22 METERS PRISMATIC COEFFICIENT .6200 CWP .7840 MAXIMUM SECTION AREA COEF. .7985 CIT .0527400 BLOCK COEFFICIENT .4951 COMPLEMENT 110. DISPLACEMENT: MOLDED 2342.73 L.T. 2380.32 METRIC TONS APPENDAGE 35.14 L.T. 35.70 METRIC TONS DOME 48.50 L.T. 49.28 METRIC TONS FULL LOAD 2426.37 L.T. 2465.31 METRIC TONS CUBIC NUMBER/100000 4.169 .1181 TOTAL ENCLOSED VOLUME 408780.60 CU.FT. 11575.38 CUBIC METERS BODY PLAN: 30 KN CUTTER GERTLER WORM: HIGH SPEED FRIGATE PCOEF (=EHP/SHP): HIGH SPEED FRIGATE BOW DOME: YES FULL LOAD MEAN TRIAL MIN. OP. DRAFT, FEET 12.39 11.96 11.82 DISPL, LONG TONS 2426.37 2292.80 2250.39 DISPL/(.01*LBP)**3 83.0434 78.4718 77.0202 GM/BEAM .0871 .0819 .0850 TRIAL SPEED, KNOTS 31.24 31.94 SUSTAINED SPEED, KNOTS 29.16 29.73 TRIPLE SCREW CODOG PROPULSION PLANT (OUTBOARD CPP PROPS, DIA=10.76 FT., RPM= 1600 CENTERLINE CPP PROP, DIA=14.2 FT.,RPM=210.00) TWO HIGH SPEED DIESELS 8325.00 HP EACH OUTBOARD P/S 31000.00 HP GAS TURBINE CENTERLINE ENDURANCE (OPERATING PROFILE): STORES & PROVISIONS = 20.00 DAYS SPEED FULL LOAD MEAN TRIAL LOAD FUEL OIL KNOTS DIST. NM DAYS DIST. NM DAYS LONG TONS 16.00 4367.42 11.37 4499.25 11.72 278.73 ENCLOSED DECK AREA (SQFT.): AVAILABLE = 30417.89 REQUIRED = 30111.44 AVAILABLE LESS REQUIRED = 306.46 OPEN WEATHER DECK AREAS: 1668.78 SQFT. FWD OF STATION 3.247 3275.97 SQFT. AFT OF STATION 15.390



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2000 LITTORAL COMBATANT WEIGHT AND KG SUMMARY --------------------- VERTICAL WEIGHT KG MOMENT LIGHT SHIP WEIGHT GROUP: (L.T.) (FT.) (FT.TONS) 1 - HULL STRUCTURE 753.17 18.13 13654.49 2 - PROPULSION PLANT 309.19 10.38 3208.55 3 - ELECTRIC PLANT 76.19 24.10 1836.32 4 - COMMAND & SURVEILLANCE 157.87 24.63 3888.64 5 - AUXILIARY SYSTEMS 224.87 20.66 4645.62 6 - OUTFIT / FURNISHINGS 193.75 25.09 4861.04 7 - ARMAMENT 74.79 36.55 2733.67 --------- --------- --------- LIGHT SHIP SUM WT. GRS. (1-7) 1789.82 19.46 34828.34 L.S. WT. MARGIN 8.000%(1-7) 143.19 L.S. KG MARGIN 4.000%KG(1-7) .78 --------- --------- --------- TOTAL LIGHT SHIP 1933.01 20.24 39119.19 FIXED LOADS: WFL1 - CREW AND EFFECTS 12.96 26.28 340.73 WFL2 - STORES AND PROVISIONS 11.79 15.76 185.71 WFL3 - POTABLE WATER 49.03 15.76 772.66 WFL4 - DIESEL OIL .01 6.02 .06 WFL5 - LUBE OIL 14.56 11.91 173.33 WFL6 - INPUT LOADS 52.92 5.00 264.60 WFL7 - AMMUNITION 53.19 29.07 1546.24 WFL8 - AVIATION AND REL.LOADS 20.17 29.95 604.09 --------- --------- --------- TOTAL FIXED LOADS 214.63 18.11 3887.42 ENDURANCE FUEL OIL 278.73 10.01 2790.94 FULL LOAD DISPLACEMENT 2426.37 18.87 45797.55 FINAL SHIP: ----------- FULL LOAD DISPLACEMENT 2426.37 LONG TONS KG - FULL LOAD 18.87 FEET



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2000 LITTORAL COMBATANT INTACT STABILITY SUMMARY: ------------------------- MIN OP LOAD MEAN TRIAL LOAD FULL LOAD FIXED WEIGHT KG WEIGHT KG WEIGHT KG LOADS (L.T.) (FT.) (L.T.) (FT.) (L.T.) (FT.) ----- ---------------- ---------------- ---------------- WFL1-CREW & EFFECTS 12.96 26.28 12.96 26.28 12.96 26.28 WFL2-STRS & PROV 3.89 21.45 7.90 18.56 11.79 15.76 WFL3-P.W. 32.85 13.75 40.70 14.72 49.03 15.76 WFL4-S.W. BALLAST 120.00 6.02 60.00 6.02 .01 6.02 WFL5-L.O. 4.80 10.31 9.75 11.12 14.56 11.91 WFL6-JP-5 17.46 1.65 35.46 3.35 52.92 5.00 WFL7-AMMO 17.55 29.07 35.64 29.07 53.19 29.07 WFL8-AVIATION 15.87 34.14 18.02 32.04 20.17 29.95 ------- ------ ------- ------ ------- ------ NON-FUEL LOADS 225.40 12.11 220.42 14.92 214.63 18.11 FUEL OIL LOAD 91.98 7.39 139.37 8.06 278.73 10.01 LIGHT SHIP WT. 1933.01 20.24 1933.01 20.24 1933.01 20.24 ------- ------ ------- ------ ------- ------ TOTAL DISPL. 2250.39 18.90 2292.80 18.99 2426.37 18.87 DRAFT, FEET 11.82 11.96 12.39 KB 7.27 7.35 7.62 + BMT 15.92 15.92 15.89 ----- ------- ------- ------- KMT 23.19 23.27 23.51 - KG 18.90 18.99 18.87 ----- ------- ------- ------- GMT 4.29 4.29 4.63 - FS CORR .60 .73 .85 ----- ------- ------- ------- GMT, FEET 3.69 3.56 3.78 GMT/B .0850 .0819 .0871



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2000 LITTORAL COMBATANT ENCLOSED DECK AREA ------------------ AREAS IN SQUARE FEET AVAILABLE: FIXED WIDTH SUPERSTRUCTURE 02LEV,100-117.5 420.00 03LEV,100-117.5 285.00 04LEV,100-117.5 175.00 G.T. INTK, 117.5-125 120.00 G.T. STACK 256.00 01LEV,172-187 540.00 02LEV ABV HNGR 216.00 03LEV ABV HNGR 120.00 HANGAR 1250.00 VARIABLE WIDTH SUPERSTRUCTURE MN DK,50-80 1207.49 MN DK,80-117.5 1570.66 MN DK, 117.5 2946.45 01LEV,80-117.5 1354.75 BRIDGE, 80-100 554.44 MN DK OUTBD. HANGAR 842.79 TOTAL DECK AREA IN SUPERSTRUCTURE 11858.58 DECKS AND PLATFORMS IN HULL HT-FWD XL-FWD HT-AFT XL-AFT 23.00 .00 20.00 50.00 1000.32 20.00 50.00 20.00 308.00 11576.66 14.50 .00 11.50 50.00 570.17 11.50 50.00 11.50 110.00 1777.11 3.00 50.00 3.00 110.00 925.32 11.50 212.00 11.50 237.00 1043.48 11.50 238.00 11.50 282.00 1666.25 TOTAL DECK AND PLATFORM AREA IN HULL 18559.31 ---------- TOTAL AVAILABLE DECK AREA 30417.89 REQUIRED: AREA CLASSIFICATION 1.1 COMMUNICATION/DETECT/EVAL 2754.00 1.2 WEAPONS 1300.00 1.3 AVIATION 1700.00 1 MILITARY MISSION PERFORMANCE 5754.00 2 SHIP PERSONNEL 11924.00 3.1 CONTROL 630.00 3.2 MN. PROPULSION SYSTEM 1425.00 3.3 AUX. SYSTEMS & EQUIPMENT 3078.29 3.4 MAINTENANCE 631.17 3.5 STOWAGE 1381.89 3.6 WING & DEEP TANKS 360.00 3.7 PASSAGEWAYS & ACCESS 3774.86 3.8 UNASSIGNED 1152.23 3 SHIP OPERATION 12433.44 ---------- TOTAL REQUIRED DECK AREA 30111.44 AVAILABLE LESS REQUIRED DECK AREA 306.46 1.02 % REQUIRED AREA OPEN WEATHER DECK AREAS: 1668.78 SQFT. FWD OF STATION 3.247 3275.97 SQFT. AFT OF STATION 15.390



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2000 LITTORAL COMBATANT TABLE OF OFFSETS ---------------- WL STA. 0 2 4 6 8 10 1.00 .00 1.63 3.88 6.01 8.14 9.39 2.00 .00 3.26 7.76 12.02 16.28 18.78 3.00 .00 4.88 11.64 18.03 24.41 28.17 5.00 .00 7.18 16.14 24.29 31.29 35.44 7.00 .00 9.18 19.62 28.74 35.23 39.12 9.00 .00 10.99 22.22 31.33 37.04 40.68 11.00 .00 12.75 24.62 33.59 38.80 42.13 13.00 .41 14.44 26.73 35.34 40.42 43.39 15.00 1.73 16.20 28.93 37.33 41.96 44.71 20.00 5.62 21.96 34.85 42.09 45.71 47.18 25.00 11.69 28.18 40.08 44.99 44.99 44.99 29.50 17.80 34.30 42.11 42.55 42.55 42.55 WL STA.12 14 16 18 20 1.00 8.89 6.13 2.38 .00 .00 2.00 17.78 12.27 4.76 .00 .00 3.00 26.67 18.40 7.14 .00 .00 5.00 34.47 27.60 16.11 1.15 .00 7.00 39.13 35.71 26.30 3.16 .00 9.00 40.95 39.09 34.09 20.56 .00 11.00 42.56 41.84 39.97 34.22 11.28 13.00 43.82 43.46 42.29 39.96 34.56 15.00 45.15 45.00 44.28 42.82 39.63 20.00 47.48 47.48 47.18 47.18 46.89 25.00 44.99 44.99 44.99 44.99 44.99 29.50 42.55 42.55 42.55 42.55 42.55



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2000 LITTORAL COMBATANT DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) SHELL & LONGL.FRMG. 111,114,116 233.00 12.39 TRANSVERSE FRAMING 115,117 46.49 11.31 MAIN DECK 131 92.22 30.06 SECOND DECK 132 28.91 20.11 PLATFORMS & INNER BOTTOM 141-9,113 35.46 8.15 STRUCTURAL BULKHEADS 121-3 55.76 14.27 MISCL. STRUCTURE 161,163,167-9 49.34 14.14 ALUM. SUPERSTRUCTURE 151-9,162 19.44 47.83 STEEL SUPERSTRUCTURE 63.55 38.50 GR2 FOUNDATIONS 182 27.83 7.74 GR3-7 FOUNDATIONS 183-7 34.19 22.86 SONAR DOME STRUCTURE 165 28.84 -1.25 MASTS 171 1.52 83.00 INPUT GR1 1.84 51.72 FREE FLOODING LIQUIDS 198 6.07 3.87 WELDING & MILL TOLERANCE 28.73 18.25 SUM GP1 753.17 18.13 PROPULSION ENGINES 233,234 67.25 11.30 REDUCTION GEARS 241,242 38.32 8.21 2 SHAFT(S) 243 64.26 2.50 SHAFT BEARINGS 244 12.85 2.50 PROPS 245 (DIA=10.76 FT., 210.00RPM-FP) 47.96 1.51 INTAKES & EXHAUSTS 251,259 40.09 38.09 OTHER GR2 SYSTEMS 252,256,261,262,264 22.50 10.25 OPERATING FLUIDS & REPAIR PARTS 298,299 15.95 6.98 SUM GP2 309.19 10.38 GENERATORS 311-3,342 28.29 19.26 SWITCHBOARDS 324 6.60 22.75 CABLE 321-3 22.52 26.49 LIGHTING 331-2 16.26 31.04 REPAIR PARTS 399 1.47 14.50 OPERATING FLUIDS 398 1.04 17.76 SUM GP3 76.19 24.10 COMMAND & SURVEILLANCE (GR4 INPUTS) 127.19 23.84 INTERIOR COMMUNICATION 431-9 10.91 28.04 DEGAUSSING 475 16.68 23.81 REPAIR PARTS & OPERATING FLUIDS 498-9 3.10 49.50 SUM GP4 157.87 24.63



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2000 LITTORAL COMBATANT DETAILS OF LIGHT SHIP WEIGHT AND KG ----------------------------------- WEIGHT KG DESCRIPTION & SWBS NUMBER (L.T.) (FEET) HEATING, VENTILATION, & AIR COND. 511-4 56.32 26.79 FIREMAINS, FLUSH SYSTEM 521,522,524 20.01 19.40 STEERING, RUDDERS 561,562 22.18 13.10 SCUPPERS, PLUMBING, DRAINS 526,528,529 23.47 16.07 FUEL OIL SYSTEMS 541 21.94 13.69 FIRE EXTINGUISHING SYSTEMS 555 10.25 21.43 ANCHOR HANDLING, MOORING, ETC. 581,582 25.01 22.03 DISTILLING & POTABLE WATER SYS. 531,533 5.68 18.16 ENVIRONMENTAL CONTROL SYSTEMS 593 5.00 10.42 BOATS AND BOAT HANDLING 583 2.25 38.67 AVIATION SUPPORT SYSTEMS 588 3.25 30.42 JP-5 SYSTEM 542 2.50 14.88 OPERATING FLUIDS 598 16.55 17.86 REPAIR PARTS 599 1.45 14.50 FAS/RAS 4.50 41.00 LIGHT WT RAST 4.50 29.00 SUM GP5 224.87 20.66 HULL FITTINGS 611,612,625,633 5.21 31.25 RIGGING & CANVAS 613 .27 34.02 LADDERS & GRATINGS 622,623 14.22 16.37 NON-STRUCTURAL BULKHEADS 621,624 43.61 27.79 PAINTING 631 17.60 19.64 DECK COVERING 634 11.92 23.54 INSULATION 635,637 38.85 27.79 SUPPORT FURNISHING 652,654-672 31.27 24.79 PERSONNEL RELATED FURNISHING 641-651 30.80 24.79 SUM GP6 193.75 25.09 WEAPONS, ARMAMENTS (GR7 INPUTS) 74.79 36.55 SUM GR(1-7) 1789.82 19.46



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2000 LITTORAL COMBATANT ELECTRIC PLANT LOAD ANALYSIS ---------------------------- ELECTRIC LOAD: SUMMER, READINESS CONDITION ONE ITEM KW (EST.) STEERING GEAR 27.10 CONTR. PITCH PROP. 20.43 PROPULSION CONTROL 10.63 PROPUL. AUX. EQUIP 70.00 DECK MACHINERY .00 SHOP EQUIPMENT 2.43 INTERNAL COMMUNIC. 4.91 DEGAUSSING 22.89 LIGHTING 42.85 HOTEL EQUIPMENT 35.75 HVAC 365.26 FIRE PUMPS 28.57 AUX. MACHY. EQUIP. 187.53 JP-5 SYSTEM .75 PAYLOAD 439.65 SUBTOTAL 1258.75 DESIGN & CONSTRUCTION MARGIN ( 15.00% ) 188.81 ---------- SUBTOTAL 1447.56 SERVICE LIFE CAPACITY MARGIN ( 20.00% ) 289.51 ---------- TOTAL MAXIMUM FUNCTIONAL LOAD 1737.07 REQUIRED CAPACITY FOR 2 GENERATOR(S) WITH LOAD MARGIN = 1.00000 1737.07 2 GENERATORS CARRYING LOAD 3 GENERATORS INSTALLED 880. KW RATING PER GENERATOR



236

2000 LITTORAL COMBATANT SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- HULL FORM PARAMETERS: LBP 308.00 FT. CP .620 1000*CV 2.806 B 43.42 FT. CX .799 D-L RATIO 80.18 T 12.39 FT. B/T 3.505 DISP-MLD 2342.73 L.T. DCF .00030 APCOR 1.55000 CAIR 1.00000 NPROP 2 UMECH .97000 EHP MARGIN 8.00% INF/SUP FAST FRIGATE BOW DOME YES DOME AREA 110.00 SQFT. WETTED SURFACE: SHIP/GERTLER 1.0200 AREA WS 13121.53 SQFT. VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 12.00 .684 607 270 271 38 95 1282 .690 1915 12.00 14.00 .798 980 260 431 60 138 1869 .690 2792 14.00 16.00 .912 1434 247 643 89 193 2607 .690 3894 16.00 18.00 1.026 2075 211 916 127 266 3595 .690 5371 18.00 20.00 1.140 2947 135 1256 174 361 4873 .690 7280 20.00 22.00 1.254 4545 27 1672 232 518 6994 .687 10503 22.00 24.00 1.368 7575 -60 2171 301 799 10785 .683 16285 24.00 26.00 1.481 11739 -56 2760 382 1186 16011 .678 24338 26.00 28.00 1.595 16006 35 3448 478 1597 21563 .672 33096 28.00 30.00 1.709 19943 249 4240 587 2002 27022 .665 41880 30.00 32.00 1.823 23901 571 5146 713 2426 32757 .660 51167 32.00 34.00 1.937 27704 1053 6173 855 2863 38647 .660 60367 34.00 36.00 2.051 31437 1657 7327 1015 3315 44751 .660 69901 36.00 38.00 2.165 35243 2427 8618 1194 3799 51280 .660 80100 38.00 40.00 2.279 39092 3389 10051 1392 4314 58239 .660 90970 40.00 42.00 2.393 42927 4570 11636 1612 4860 65604 .660 102474 42.00 INSTALLED POWER: 47650.00 HP 35532.61 KW SPEED: TRIAL 31.24 KNOTS AT INSTALLED POWER SUSTAINED 29.16 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 16.00 4367.42 11.37 3894.45 .55938 278.73 TOTAL 4367.42 11.37 278.73 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 278.73 L.T.



237

2000 LITTORAL COMBATANT SPEED-POWER ESTIMATE FOR FULL LOAD ---------------------------------- DETAILS OF BARE HULL EHP ESTIMATE VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 12.00 .684 .518 2.169 217.17 1.677 390.00 607.17 12.00 14.00 .798 .667 1.810 370.62 1.644 608.95 979.57 14.00 16.00 .912 1.124 1.044 538.12 1.616 895.95 1434.08 16.00 18.00 1.026 1.864 .670 815.65 1.592 1259.71 2075.35 18.00 20.00 1.140 2.292 .603 1237.86 1.571 1708.80 2946.66 20.00 22.00 1.254 3.208 .600 2293.60 1.552 2251.73 4545.33 22.00 24.00 1.368 4.841 .625 4678.16 1.536 2896.93 7575.09 24.00 26.00 1.481 6.361 .646 8086.36 1.521 3652.77 11739.13 26.00 28.00 1.595 6.870 .680 11478.00 1.507 4527.54 16005.54 28.00 30.00 1.709 7.015 .680 14413.98 1.494 5529.48 19943.46 30.00 32.00 1.823 6.911 .680 17233.96 1.482 6666.78 23900.73 32.00 34.00 1.937 6.605 .680 19756.40 1.471 7947.60 27703.99 34.00 36.00 2.051 6.212 .680 22056.94 1.461 9380.02 31436.96 36.00 38.00 2.165 5.812 .680 24270.81 1.452 10972.12 35242.92 38.00 40.00 2.279 5.412 .680 26360.13 1.443 12731.91 39092.03 40.00 42.00 2.393 5.012 .680 28259.92 1.434 14667.37 42927.29 42.00 KEY TO ABBREVIATIONS: VK SPEED IN KNOTS VLR VK/SQRT(LBP) WORM WORM CURVE (INF/SUP = CR-SHIP/CR-GERTLER) *CR 1000.0*CR EHPR RESIDUARY RESISTANCE EHP (FORM DRAG EHP) *CF 1000.0*CF EHPF FRICTIONAL RESISTANCE EHP (INCL. CFRICT) EHPBH EHPR+EHPF (BARE HULL EHP) EHPDM DOME DRAG EHP EHPAPP APPENDAGE DRAG EHP (EXCLUDING DOMES) EHPAIR STILL AIR DRAG EHP EHPMAG EHP MARGIN EHPT TOTAL EHP (BRITISH HP = 550 FT.LB./SEC.) PC PROPULSIVE COEFFICIENT = EHPT/SHP UMECH=SHP/BHP HP TOTAL HORSE POWER INCLUDING THE EFFECTS OF PC & UMECH HP=SHAFT HORSE POWER (SHP) IF UMECH=1.00 HP=BRAKE HORSE POWER (BHP) IF UMECH<1.00



238

2000 LITTORAL COMBATANT SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ---------------------------------------- HULL FORM PARAMETERS: LBP 308.00 FT. CP .609 1000*CV 2.638 B 43.24 FT. CX .794 D-L RATIO 75.36 T 11.96 FT. B/T 3.617 DISP-MLD 2201.93 L.T. DCF .00030 APCOR 1.55000 CAIR 1.00000 NPROP 2 UMECH .97000 EHP MARGIN 8.00% INF/SUP FAST FRIGATE BOW DOME YES DOME AREA 110.00 SQFT. WETTED SURFACE: SHIP/GERTLER 1.0200 AREA WS 12725.33 SQFT. VK VLR EHPBH EHPDM EHPAPP EHPAIR EHPMAG EHPT PC HP VK 12.00 .684 592 270 262 38 93 1256 .690 1876 12.00 14.00 .798 934 260 416 60 134 1804 .690 2695 14.00 16.00 .912 1343 247 621 90 184 2484 .690 3712 16.00 18.00 1.026 1903 211 884 128 250 3376 .690 5044 18.00 20.00 1.140 2708 135 1213 175 338 4569 .690 6827 20.00 22.00 1.254 4226 27 1614 233 488 6588 .687 9893 22.00 24.00 1.368 7076 -60 2096 303 753 10167 .683 15352 24.00 26.00 1.481 10798 -56 2664 385 1103 14894 .678 22640 26.00 28.00 1.595 14861 35 3328 481 1496 20202 .672 31007 28.00 30.00 1.709 18526 249 4093 592 1877 25337 .665 39269 30.00 32.00 1.823 22152 571 4967 718 2273 30682 .660 47925 32.00 34.00 1.937 25615 1053 5958 861 2679 36166 .660 56492 34.00 36.00 2.051 29022 1657 7073 1022 3102 41876 .660 65411 36.00 38.00 2.165 32480 2427 8318 1203 3554 47982 .660 74948 38.00 40.00 2.279 35961 3389 9702 1403 4036 54492 .660 85116 40.00 42.00 2.393 39408 4570 11231 1624 4547 61380 .660 95876 42.00 INSTALLED POWER: 47650.00 HP 35532.61 KW SPEED: TRIAL 31.94 KNOTS AT INSTALLED POWER SUSTAINED 29.73 KNOTS AT 80.00% POWER RANGE: VCRUS RANGE DAYS HPCRS SFC FUEL KNOTS N.M. LBS/HP/HR L.T. 16.00 4499.25 11.72 3712.07 .56966 278.73 TOTAL 4499.25 11.72 278.73 RANGE = CRG*(FUEL*VCRUS*2240)/(HPCRS*SFC) DAYS = RANGE/(24*VCRUS) CRG .952400 FUEL 278.73 L.T.



239

2000 LITTORAL COMBATANT SPEED-POWER ESTIMATE FOR MEAN TRIAL LOAD ---------------------------------------- DETAILS OF BARE HULL EHP ESTIMATE VK VLR *CR WORM EHPR *CF EHPF EHPBH VK 12.00 .684 .526 2.169 214.06 1.677 378.23 592.29 12.00 14.00 .798 .637 1.810 343.48 1.644 590.56 934.04 14.00 16.00 .912 1.021 1.044 473.84 1.616 868.90 1342.74 16.00 18.00 1.026 1.606 .670 681.45 1.592 1221.67 1903.12 18.00 20.00 1.140 2.006 .603 1050.66 1.571 1657.20 2707.86 20.00 22.00 1.254 2.945 .600 2042.02 1.552 2183.74 4225.76 22.00 24.00 1.368 4.552 .625 4266.47 1.536 2809.46 7075.94 24.00 26.00 1.481 5.885 .646 7255.24 1.521 3542.48 10797.71 26.00 28.00 1.595 6.463 .680 10470.52 1.507 4390.83 14861.35 28.00 30.00 1.709 6.606 .680 13163.87 1.494 5362.52 18526.39 30.00 32.00 1.823 6.486 .680 15686.78 1.482 6465.48 22152.26 32.00 34.00 1.937 6.173 .680 17907.38 1.471 7707.62 25615.00 34.00 36.00 2.051 5.786 .680 19925.34 1.461 9096.80 29022.14 36.00 38.00 2.165 5.392 .680 21838.71 1.452 10640.82 32479.53 38.00 40.00 2.279 4.999 .680 23613.72 1.443 12347.48 35961.20 40.00 42.00 2.393 4.605 .680 25183.40 1.434 14224.50 39407.91 42.00



240

APPENDIX 9.5

SHIP RULES AND STANDARDS COMPARISON TABLE



241

Country Rules/standards Notes/Requirement Verification (at design stage) 2.3. Non-Government Documents SLCs: -Classification rules applied

FIN DNV High Speed Light Craft Built according to but not classified - GER BWB-Rules for Navy Ships

GRE DNV NOR DNV High Speed Light Craft 93 and 96, modified by

RnoN/FiReCo (strengthened) Generally built according to but not classified. Several additional aspects included with respect to materials details and level of analyses (FNoN/FiReCo)

Full scale test on prototype.

PL PN Rules and requirements, partially PRS Rules Built according to but not classified Full scale exploiting-military test o

Navy supervision SWE RMS- Rules for Military Ship (Sweden)/DNV RMS-Required, DNV not required - UKRNavy Not applied - - TUR

Korvet -

TUR

Firkateyn -

OPVs CAN Lloyd´s Rules for the Classifiaction of Ships LRS +100 A1 Ice Class D, +LMC CCS - GER BWB rules for Navy Ship ITA NAV-23-A1; RINA Built according to but not classified - NDL Lloyd's Rules, Special Service Craft (SSC) "cross" 100 A1 SSC, Patrol Craft, SSC, G5, "cross" LMC,

UMS -

PL PRS Rules and add. req. PL CG Built according and classified UKRCoast Russian Register of Shipping Should comply, but not classified - UK DNV Rules for Classification of High Speed, Light Craft

and Naval Surface Craft - -

U.S. Coast

Guard None - -



242

-FMEA applied SLCs:

FIN IMO High Speed Craft Code - -

GRE IMO NOR IMO High Speed Craft Code - - PL IMO and PL gov. standards-additional informations and

req.

SWE IMO Required - UKRNavy Ukrainian government standards - Navy supervision TUR

Korvet -

TUR

Firkateyn -

OPVs CAN IMO - - GER - ITA IMO HSC - NDL IMO High Speed Craft For the navigation lighting - PL IMO UKRCoast Ukrainian government standards - CG supervision UK - - - U.S. Coast

Guard None - -



243

- Environmental regulations SLCs:

FIN MARPOL, FMA regulations - - GRE MARPOL GER MARPOL, BV 4500-1 required acceptance test NOR MARPOL, NMA regulations Partly - PL MARPOL, SOLAS Additional Navy requirements Navy supervision SWE MARPOL Required - UKRNavy MARPOL Should comply with established requirements Navy supervision TUR

Korvet IMO-SOLAS

TUR

Firkateyn Sewage IMO

OPVs CAN CSA, MARPOL, USCG CSA = Canada Shipping Act - ITA MARPOL - NDL MARPOL - - PL MARPOL PL Maritime Administration (UM) UKRCoast MARPOL Should comply with established requirements CG supervision UK MARPOL - - U.S. Coast

Guard MARPOL,AnnexI,II,IV,V and VI,33 CFR 51 and 21 CFR 1240.20

- -



244

- Personnel safety onboard SLCs:

FIN The Finnish Board of Labour Protection Regulations Non Combat areas - GRE GER SOLAS, UVV See, BV 1770-1, BV 1830-1 Required NOR RNoN customs, EU regulations Non Combat areas - (law on occupational safety, health & welfare of

personnel)

PL Navy standards and Navy Rules SWE RMS- Rules for Military Ship (Sweden)/DNV Required - UKRNavy Ukrainian government standards, Navy regulations Correspondence to medical-sanitary codes, ensuring of

safety of life at sea Navy supervision

TUR

Korvet NATO ANEP 24 (ANEP 25,26,27)

TUR

Firkateyn -

OPVs CAN CSA, MARPOL (SOLAS) - - ITA NAV 05-11-13; CEI Directive NAV by Italian Navy - NDL National Shipping Inspectorate (NSI) & EU/Dutch law PL PL gov. health and safety legislation MARPOL, SOLAS and maritime administration requirements UKRCoast Ukrainian government standards, Navy regulations Correspondence to medical-sanitary codes, CG supervision UK Relevant UK Health and Safety legislation - - U.S. Coast

Guard per General Specification for Ships of the United States Navy

- -



245

4.2. Hydrodynamics (Mobility) SLCs: 4.2.2. Seakeeping performance FIN - Required capability in different wave heights Model tests (H1/3 = 3-4m / 2-3m / 2m) GRE Required capability in different wave heights: H1/3 (3.5 m

and 6 m). Computer calculations

GER STANAG 4154, ANEP 15 Customer Requirements Model Test

NOR STANAG 4154, 4194, ANEP 11, 15 Required capability in different wave heights Model tests and full scale tests PL Navy Rules and regulations, additionally int. standards Required capability in different wave heights Model tests/computer simulations SWE Requirement from Swedish Navy in co-operation with

FMV Different demands on different size of ships. Simulations/ Model test/ Full Scale test

UKRNavy Ukrainian Navy regulations Safety navigation at any sea state with transit speed 12 kt.,

combat employment at sea state up to 4 Model tests

TUR

Korvet STANAG 4154, ANEP 15

TUR

Firkateyn STANAG 4154 Rolltests: BV 0631.3

OPVs CAN TSOR Specified in Technical Statement of Requirments (TSOR) Model Tested

ITA STANAG 4154 Ed.4 Required capability in different wave heights:

H1/3 (2.5-4 m/1,25-2,5 m). Model tests

NDL Operational requirement Max 26 knots, required seastate 5, 23 knots.

(seastate 4 for working with RIB) Global waves statistics (BMT) area 47 Downtime waves incomming ahead 0.35 g (on the bridge) Downtime waves incomming at side 0.2g (on the bridge)

In proposal: calculations program SEAWAY during detailed design: Modeltests at MARIN

PL Operational requirements Hydrometeorological conditions on the Baltic Sea Model tests UKRCoast Ukrainian Navy regulations Safety navigation at any sea state with transit speed 12 kt.,

combat employment at sea state up to 4 Model test

UK Customer requirements Computer prediction U.S. Coast

Guard Coast Guard Standard for Transit Motion Criteria Roll <8.0 SSA -

Pitch <3.0 SSA



246

Deck Wetness <30 per hour Slams @ Stat 2 <20 per hour Vert. Accel. <0.4g at manned watch stations Lat. Accel. <0.2g at manned watch stations Coast Guard Standard for Boat Launch and Recovery Roll <8.0 SSA Pitch <2.5 SSA Vert Accel <0.2g SSA on Boat Deck Lat Accel <0.2g SSA on Boat Deck



247

4.2.3. Speed/Power SLCs:

FIN - - Model tests GRE GER BV 2000-1 Customer Requirements Model Test, Full Scale Acceptance Test NOR - Design by RNoN Model tests and full scale tests PL Navy Requirements Design guidelines and req. Model tests and full scale tests SWE Requirement from Swedish Navy in co-operation with

FMV - Calculations/ Simulations/ Model tests

and full scale test UKRNavy Ukrainian Navy regulations Full speed 30+ kt.,cruising speed 14kt. (2500 N.M.) Model tests TUR

Korvet -

TUR

Firkateyn -

OPVs CAN TSOR Design Guidelines Model Tested ITA Requirements from I.N. in cooperation with F/C CFD/ Analysis Model tests NDL Oper.requirement (no rules/standards), max.cont.power

i.a.w. ISO 3046

PL PL CG Operational Requirements Design guidelines Model tests and full scale tests UKRCoast Ukrainian Navy regulations Full speed 18 kt.,cruising speed 12 kt. (3800 N.M.) Model tests UK Customer requirements Model test U.S. Coast

Guard Coast Guard Standard Speed Derfined in Operational Requirements Document.

Sustained Speed shall be achieved at 80 of Mean Continous Rtaing of the engines. Trial Speed shall be achieved at 100 percent of Mean Continous Rating of the engines.

-



248

4.2.4. Maneuverability SLCs: FIN - Design quidelines by Finnish Navy Model tests GRE Design guidelines by Hellenic Navy NOR - Design by RNoN Model tests and full scale tests PL Navy Requirements and standards Design guidelines by PN Calculations/Model test and full scale

tests SWE Requirement from Swedish Navy in co-operation with

FMV - Calculations/ Model test and full scale

tests UKRNavy Ukrainian Navy regulations Tactical turning diameter not greater than 7 ship lengths,

steady heel should not exceed 12 degrees Model tests

TUR

Korvet -

TUR

Firkateyn -

OPVs CAN TSOR Design Guidelines Model Tested GER VG81208, DIN81208, IMO Resolution A.601 (15) Customer Requirements Calculation, Simulation, Model Test,

Trials ITA IMO and requirement from I.N. in cooperation with F/C SIM SUP studies (by CETENA) Model tests NDL Operational requirement (no rules/standards used) PL Navy Operational requirement Design guidelines Calculations/Model test and full scale

tests UKRCoast Ukrainian Navy regulations Tactical turning diameter not greater than 5 ship lengths,

steady heel should not exceed 12 degrees Model tests

UK IMO Resolution A.751 ”Interim Standards for Ship

Manoeuvrability” and IMO Resolution A.601 (15) paragraphs 4.3.1. and 4.3.4.

Computer prediction

U.S. Coast

Guard Coast Guard Standard Tactical Turning Diameter not greater than 5 ship lengths at

max speed. Stopping Distance not greater than 3 ship lengths at max speed.

Model Tests, Trials



249

4.2.5. Accessibility SLCs: (Drafts, canal transit req., etc.) FIN - - - GRE - GER - NOR - Design by RNoN - PL Navy req. Hydrografic Office PN SWE Requirement from Swedish Navy in co-operation with

FMV - -

UKRNavy Ukrainian Navy operational requirements Navigational draft not greater than 3.2 meters Numerical computation TUR

Korvet -

TUR

Firkateyn -

OPVs CAN -

Poor Computer Accessibility (Due to Shape and Propulsion)

-

ITA None Design guidelines by Italian Navy NDL None PL Non, add. Navy req. and Maritime Administr. Design guidelines UKRCoast Ukrainian Navy operational requirements Navigational draft not greater than 4 meters Numerical computation UK - - - U.S. Coast

Guard Coast Guard Standard Navigational Draft not greater tha 4.5 meters. Analysis, Examination



250

4.4. Total ship survivability SLCs: 4.4.4. Vulnerability - Shock load requirements (equipment, machinery)

FIN Finnish Navy Standard: Environmental Requirements for Shipborne equipment

- Laboratory tests

GRE GER BV 0430, BV 0440, BV 0280, BV 0281 Customer Requirements Equipment Tests NOR PL Navy standard, PN Rules and add. Stanags Shock trial and design guidelines Laboratory tests SWE Requirement from Swedish Navy in co-operation with

FMV Laboratory tests

UKRNavy Ukrainian government standards Requirements vary in accordance with items' type and

location Factory tests for some items

TUR

Korvet Testing: STANAG 4141, STANAG 4142, Underwater schock testing: STANAG 4137, STANAG 1097

TUR

Firkateyn Switchboard, switching equipment. Shock and vibr. BS 04

OPVs CAN TSOR Design Guidelines Laboratory Tested ITA STANAG 4137 Shock trial NDL None CG requirement and guidelines PL Not required UKRCoast Ukrainian government standards Requirements vary in accordance with items' type and

location Factory tests for some items

UK - U.S. Coast

Guard Not required



251

Ballistic protection requirements SLCs: FIN - Protection of vital spaces against splinters and light arm fire,

design guidelines by Finnish Navy Laboratory tests

GRE H.N. requirements NOR PL According to PN standard and STANAGS Protection of vital spaces and design guidelines Laboratory tests SWE Requirement from Swedish Navy in co-operation with

FMV Protection of separate vital spaces. Laboratory test/ Calculations

UKRNavy Ukrainian Navy regulations Limited fragmentation protection of separate vital spaces Navy supervision TUR

Korvet -

TUR

Firkateyn -

OPVs CAN TSOR Design Guidelines,

Protection of Vital Areas against Small Arms Fire

ITA STANAG 4141-4150-4549 Shock test procedure and shock level Shock test STANAG 4142 Shock resistence and analysis for surface ship ANEP 43 Vulnerability and analysis: new issue under development NDL threat i.a.w. CEN Protection of the nav. bridge against light arm ammunition Laboratory tests PL Not required UKRCoast Ukrainian Navy regulations Limited fragmentation protection of separate vital spaces CG supervision UK Classified UK Naval Engineering Standard Magazine protection U.S. Coast

Guard Not required



252

-NBC requirements SLCs: FIN - Design guidelines by Finnish Navy - GRE H.N. requirements GER STANAG 4447, BV 4600-1 Customer Requirements Full Scale Acceptance Tests NOR RNoN Rules and Regulations - - PL PN Rules and requirements, add. STANAGS Design guidelines Navy supervision SWE Requirement from Swedish Navy in co-operation with

FMV

UKRNavy Ukrainian Navy regulations Functioning of main command posts after NBC weapon

employment, presence of decontamination facilities Navy supervision

TUR

Korvet -

TUR

Firkateyn -

OPVs CAN - None Required ITA NAV 06A061 STANAG 4447 UMM 1239 NDL none Gastight closure of the accommodation by GT doors PL none UKRCoast Ukrainian Navy regulations Functioning of main command posts after NBC weapon

employment, presence of decontamination facilities CG supervision

UK - U.S. Coast

Guard Provide personal protection suits (with stowage), decontamination showers, and CBR detection devices. Consistent with OPNAVIN



253

- Fire protection SLCs: FIN DNV High Speed Light Craft rules - - GRE H.N. requirements GER BV 4400-1, BV 4300-1 NOR RNoN Rules and Regulations, and IMO Res A653, 654,

754, ISO 9705, 5660

Partly fulfilled Full scale fire test (Room Control)

PL PN Rules and regulations, gov. standards, add. PRS rules Navy requirements Navy supervision SWE RMS-Rules for Military Ships /IMO Required Full Scale tests UKRNavy Ukrainian government standards, Navy regulations In time fire detection and suppression, proper design

solutions and layout Navy supervision

TUR

Korvet Detection: SOLAS and other class socities

TUR

Firkateyn Seawater Five Fight., Prewelling, sprigler BV44 Firefighting layout BV44 Halon system, GL, SOLAS Springler and Prewettings. Layout BV0443

OPVs CAN Lloyd´s Rules, CSA, USCG SMM 69 ITA RINAMIL NDL Lloyd's Rules, SSC (i.a.w. SOLAS/NSI-High Speed Craft) Ammunition stores l.a.w. IMDG approval by class/NSI PL PRS Rules and conventions Ammo acording to Navy Standard PL CG supervision UKRCoast Ukrainian government standards, Navy regulations In time fire detection and suppression, proper design

solutions and layout CG supervision

UK MCA, DNV and SOLAS U.S. Coast

Guard per General Specifications for Ships of the United States Navy

-



254

4.5. Signature Management SLCs: 4.5.1. Radar Cross-Section FIN - Design guidelines by Finnish Navy - GER BV 0403, BV 0460-1 Customer Requirements Simulation, Measurement GRE H.N. requirements NOR Concept developed by RNoN/FiReCo and DERA Design requirements by RNoN and Norwegian Defence

Research Establishment Numerical simulations and full scale tests

PL PN requirements/co-operation with Naval Shipyard and

B&V PN requirements

SWE Requirement from Swedish Navy in co-operation with

FMV Simulation programs/

full scale tests UKRNavy Ukrainian Navy regulations RCS should comply with established levels PC modelling TUR

Korvet -

TUR

Firkateyn -

OPVs CAN - None Required ITA None required Design guidelines by Italian Navy NDL n.a. PL n.a. n.a. UKRCoast Not applied None UK U.S. Coast

Guard No Requirements



255

4.5.2. Infrared signature SLCs: FIN - Design guidelines by Finnish Navy - GER BV 0403, BV 0470-1 Customer Requirements Simulation, Measurement GRE H.N. requirements NOR Design guidelines by RNoN and Norwegian Defence

Research Establishment Numerical simulations

PL PN Requirements Design guidelines Full scale tests SWE Requirement from Swedish Navy in co-operation with

FMV Calculations/ Full scale tests

UKRNavy Ukrainian Navy regulations IS should comply with established levels PC modelling TUR

Korvet -

TUR

Firkateyn -

OPVs CAN - None Required ITA None required Design guidelines by Italian Navy NDL n.a. PL Not required UKRCoast Not applied None UK U.S. Coast

Guard Not required



256

4.5.3. Acoustic signature SLCs: FIN - Damping elements etc,design guidelines by Finnish Navy - GER BV 0403, BV 0450 Customer Requirements Simulation, Measurement GRE STANAG 4293 H.N. requirements NOR RNoN Rules and Regulations PL PN Rules and requirement Design guidelines Laboratory tests and full scale tests SWE Requirement from Swedish Navy in co-operation with

FMV Damping elements according to Swedish Navy Standard Full scale test

UKRNavy Ukrainian Navy regulations AS should comply with established levels PC modelling TUR

Korvet (Airborne noise STANAG-4293)

TUR

Firkateyn -

OPVs CAN TSOR Design Guidelines Laboratory Tested ITA STANAG 1136 Standard for use when measuring reporting radiated nois e

(requirement not included in the standard) Acoustic range tests

Noise: Nav 05A143 Ed. 1985 – STANAG 4293 Usually applied for measuring procedure – limits to be defined with Italian Navy

Vibration: NT 60612 MMI Ed. 90 Usually applied for measuring procedure – limits to be defined with Italian Navy

NDL n.a. PL Not required Designing process tests UKRCoast Ukrainian Navy regulations AS should comply with established levels PC modelling UK U.S. Coast

Guard Not required



257

4.5.4. Magnetic signature SLCs: FIN - MS-system installed, design guidelines by Finnish Navy Laboratory measurement for

components GER BV 0403, BV 0420 Customer Requirements Simulation, Accepatance Tests,

Measurement GRE H.N. requirements NOR PL PN requirements and standards Design guidelines Modelling and full scale tests SWE Requirement from Swedish Navy in co-operation with

FMV Guidelines from FMV

UKRNavy Ukrainian Navy regulations MS should comply with established levels PC modelling TUR

Korvet NATO AMP-14

TUR

Firkateyn -

OPVs CAN TSOR Design Guidelines Laboratory Tested ITA AMP 14 (STANAG) NDL n.a. PL Not required UKRCoast Ukrainian Navy regulations MS should comply with established levels PC modelling UK U.S. Coast

Guard Not required



258

4.5.5. Optical signature SLCs: (Including painting) FIN - Design guidelines by Finnish Navy - GER Customer Requirements GRE NOR Design guidelines by RNoN and Norwegian Defence

Research Establishment Simulations

PL General design guidelines SWE Requirement from Swedish Navy in co-operation with

FMV Painting pattern / Color Scheme for the ship

UKRNavy Ukrainian Navy regulations VS should comply with established levels PC modelling TUR

Korvet -

TUR

Firkateyn -

OPVs CAN - None Required ITA Not required NDL Operational requirement Color scheme (dark grey) PL Not required UKRCoast Not applied None UK U.S. Coast

Guard Not required



259

4.5.6. Wake SLCs: FIN - - - GRE NOR PL Model test SWE CFD-tests UKRNavy Not applied None TUR

Korvet -

TUR

Firkateyn -

OPVs CAN - None Required ITA CFD analysis Model test/ ITTC 78 NDL n.a. PL Not required UKRCoast Not applied None UK U.S. Coast

Guard Not required



260

4.5.7. Electromagnetic emissions SLCs: FIN Finnish Navy Standard: Electrical installation on Military

Vessels EMC separated spaces Laboratory measurement for

components GER MIL-STD 462, VG 95371, 95372, 95373, 95374, BV 0120,

BV3000-1, GL EMV/GL 120 Customer Requirements Simulation, Measurement, Acceptence

Tests (equipment) GRE NOR VG 95373, 374, RNoN Rules and Regulations PL PN standard and requirements Design guidelines SWE Requirement from Swedish Navy in co-operation with

FMV Design guidelines

UKRNavy Ukrainian government standard, navy regulations Proper installation of emitting devices, EM decoupling of

vessel's spaces EMI PC modelling

TUR

Korvet MIL-STO 461, 4652, 1310

TUR

Firkateyn EMI/EMC Measurement BV 30

OPVs CAN - All Equipment to Commercial Standards for Emmisions ITA Italian Navy Standards NDL none, radar-suite Thales/SCOUT -radar specified PL Governement standard and PRS rules UKRCoast Ukrainian government standard, navy regulations Proper installation of emitting devices, EM decoupling of

vessel's spaces EMI PC modelling

UK U.S. Coast

Guard Per General Specifications for Ships of the United States Navy



261

4.6. Stability SLCs: 4.6.3. Intact stability FIN Finnish Maritime Administration req. –72, IMO res A469,

USCG Weather Criteria

GER BV 1033-1, BV 1030-1 GRE DDS 079 & IMO Requirements NOR RNoN Rules and regulations (with air cushion correction) Numerical simulations PL PN rules and regulations Design guidelines Numerical simulations SWE RMS-Rules for Military Ships/ IMO regulations Required Calculations with NAPA UKRNavy Ukrainian Navy regulations Should withstand the wind up to 32 m/s (in conditions

pointed in i.4.2.2 plus 25 degrees' roll) Numerical computation

TUR

Korvet BV 1033

TUR

Firkateyn BV 1033

OPVs CAN TSOR Stability & Bouyancy Requirements for Canadian Armed

Forces Surface Ship (C-03-001-024-MS002) (Exceeds Lloyds)

ITA NAV RINAMIL Calculation with Sap NDL Netherlands Shipping Inspectorate (l.a.w. SOLAS) l.a.w. SOLAS approval by NSI PL PRS Rules and conventions Numerical computation UKRCoast Ukrainian Navy regulations Should withstand the wind up to 32 m/s (in conditions

pointed in i.4.2.2 plus 25 degrees' roll) Numerical computation

UK IMO Code of Safety for Special Purpose Ships and NES

109 calculation

U.S. Coast

Guard In accordance with U.S. Navy DDS 079-1 100 knot beam winds



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4.6.4. Damage stability SLCs: FIN Special requirements on residual stability set by Finnish

Navy 1-compartment damage also 2-comp. damages calculated

GER BV 1033-1, BV 1030-1 GRE DDS 079 & IMO Requirements NOR RNoN Rules and Regulations 2-comp. Damage Numerical simulations PL PN Rules and standards PN requirements Numerical computation and simulations SWE RMS-Rules for Military Ships/ IMO requirements 2-compartments, for new design 3 compartments Calculations with NAPA UKRNavy Ukrainian Navy regulations To be afloat after flooding of 2 adjacent compartments Numerical computation TUR

Korvet BV 1033

TUR

Firkateyn BV 1033

OPVs CAN TSOR C-03-001-024-MS002 (Any 2 Adjacent Compartment

Damage)

ITA NAV 0,4-A013 Ed.81, RINAMIL 2 comp. damages calculated respetting the 15% of

longitudinal extention flooding Calculation with SAP

NDL Netherlands Shipping Inspectorate (l.a.w. SOLAS) 1-compartment damage, l.a.w. SOLAS approval by NSI PL PRS and conventions Numerical computation UKRCoast Ukrainian Navy regulations To be afloat after flooding of 2 adjacent compartments Numerical computation UK IMO Code of Safety for Special Purpose Ships and NES

109 calculation

U.S. Coast

Guard In accordance with U.S. Navy DDS 079-1 Withstand flooding of any two adjacent compartments



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5.1. Hull structure SLCs: - Sealoads FIN DNV High Speed Light Craft and Direct Calculations FEM analysis, fatique tests GER BV 1040-1, BV 1050-1, German Lloyd Claculations, FEM Analysis, Full Scale

Tests GRE DNV NOR DNV High Speed Light Craft (modified), Direct

calculations, model tests

Modified by RNoN/FiReCo FEM analysis, extensive measurementsby fiber-optic sensor cable system (CHESS)

PL PN rules and add. PRS rules PN requirements Numerical computation SWE RMS-Rules for Military Ships/ DNV High Speed and Light

Craft RMS Required FEM analysis, calculated, Full Scale

tests UKRNavy Ukrainian Navy regulations Should comply with established levels Numerical computation TUR

Korvet Ship structure Residual strength ANEP 43 Steel Structures NES 110, BV 1040 etc.

TUR

Firkateyn German Lloyd

OPVs CAN Lloyd´s Rules + Calculations Rule based and FEA ITA RINAMIL FEM analysis, fatique tests NDL Lloyd's Rules l.a.w. rules for Special Service Craft (SSC) approval by class/NSI PL PRS Rules Numerical computation UKRCoast Ukrainian Navy regulations Should comply with established levels Numerical computation UK DNV Rules for Classification of High Speed,

Light craft and Naval surface craft Calculation

U.S. Coast

Guard Per General Specifications for Ships of the United States Navy



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- Shockloads SLCs: FIN Finnish Navy Standard: Environmental Requirements

for Shipborne equipment

GRE NOR RNoN Rules and regulations, modified PL PN Rules and regulations Design guidelines SWE Requirement from Swedish Navy in co-operation with

FMV environmental requirements Design guidelines

UKRNavy Ukrainian Navy regulations Should comply with established levels Numerical computation TUR

Korvet -

TUR

Firkateyn -

OPVs CAN TSOR Design Guidelines ITA Whipping calculation in according with Italian Navy NDL n.a. PL Not applied UKRCoast Ukrainian Navy regulations Should comply with established levels Numerical computation UK U.S. Coast

Guard Not applied



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- Special loads (ice etc.) SLCs: FIN DNV Rules (modified) >10 cm level ice, >40 cm broken ice GER German Lloyd Rules Customer Requirements GRE NOR Detailed tailored specification Ice tests have been succesfully performed in 10 cm ice PL PN Rules and PRS Rules SWE RMS-Rules for Military Ship (Sweden)/

Requirement from Swedish Navy in co-operation with FMV

UKRNavy Ukrainian Navy regulations Navigation in broken ice Numerical computation TUR

Korvet -

TUR

Firkateyn -

OPVs CAN Lloyd´s Rules Ice Class D ITA RINAMIL NDL operational requirement additional steel/rubber fendering PL PRS Rules Ice Class 4 UKRCoast Ukrainian Navy regulations Navigation in broken ice Numerical computation UK U.S. Coast

Guard Not applied



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5.5. Electric Installations SLCs: FIN Finnish Navy Standard: Electrical installation on Military

Vessels, DNV rules Part 4 Ch 4-6

GER STANAG 1008, BV3000-1, VDE Rules, German Lloyd

Rules

GRE H.N. requirements NOR RNoN rules and regulations/DNV HSLC PL PN Rules and standards SWE RMS-Rules for Military Ships and national standards Where required for military communications equipment,

aqn enhanced quality supply will be provided to meet STANAG 1008.

UKRNavy Ukrainian government standards All modes of vessel's employment, including emergency

modes, should be ensured Numerical computation

TUR

Korvet El. power Generation and distrib. STANAG 1008 Design of El. equip. MIL-E917, MIL-STB-2036 Equipment encl. for IEEE Standard 45, BV30, MIL-E-2036 Power supply and charging units MIL-P-15376, MIL-C-24638

TUR

Firkateyn Main electric power system, STANAG 1008, BV 30, DOD-STD1399 Electrical plant, STANAG 1008, DOD-STD-1399

OPVs CAN Lloyd’s Rules, CSA Classed for Unmanned Machinery Spaces (Local and

Central) Control System (LRS + LMC CCS)

ITA Rina electrical installation-Merchant Vessels Sez.D Ed.

1998; CEI CEI rules when Rina is not applicable

NAV-13-A095 (CAP IX); NAV-13-A083;SMM/II-107 SMM/II-107 rules for prevention of boarding Propulsion: Rina Sec. C-D NDL Lloyd's Rules-SSC PL PRS Rules UKRCoast Ukrainian Government standards All modes of vessel's employment, including emergency

modes, should be ensured Numerical computation



267

UK 1990 Institution of electrical engineers regulations for the electrical and electronic equipment of ships with 1994 supplement

U.S. Coast

Guard 46 CFR, IEEE 45



268

APPENDIX 9.6

CHARACTERISTICS OF SHIPS CONSIDERED IN RULES AND STANDARDS COMPARISON



269

Finnish Navy

HAMINA-Class Missile Boat

HAMINA 1998 TORNIO 2003

MAIN DIMENSIONS: Length, max 50,8 m Length, wl 44,3 m Breadth, wl 8,3 m Displacement 240 t Draft 1,7 m Speed 30+ kn Crew 21 Endurance 500+ nautical miles Stores 5 days operations Built by Aker Finnyards, Rauma, Finland Main Engines 2 * MTU 16V 538 TB 93 diesels, 3300 kW each, in separate engine rooms Shafts from gear to waterjet, are made of carbon fiber Propulsion 2 * KaMeWa 90SII waterjet units with 7-bladed impellers Weapons SSM RB S15 SAM Kentron Umkhonto

GUN Bofors 57 mm L70 Mk3 Mines Torpedoes

Sensors etc. EADS TRS 3D ES-16, Surveillance and target acquisition radar system SAGEM EOMS, Combined IRST and EOD SAAB CEROS 200, Target acquis ition and tracking system THALES EW, Laser-ESM, Radar-ESM, CMDL Hull material is aluminium. Superstructure is made of composite sandwich panels. The EMC-shield is integrated to the primary structure. Radar absorbent material and ballistic protection is used in specific areas. Designed for surface patrol, combat and escort missions. Hamina -class vessels can also operate as squadron command vessels. At peace time, the mission is to: secure territorial integrity, repel territorial violations, lead underwater surveillance and participate in international co-operation. At wartime ships are capable of: surface combat and lead missions, escorting and protecting marine traffic and mine laying.



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Skjold class FPB Description and missions/tasks. The Skjold class FPB is a versatile high -speed SES vessel, with long range tactical anti-shipping missiles, a multipurpose (AAW,ASUW,NGS) gun, and short range SAM. The ship's displacement is 270 tonnes, 47m LOA and 13.5m BOA. It has a minimum speed of 48 knots in SS3, and a top speed of almost 60 knots in calm water. The main weapons systems of the FPB is 8 SSMs (Norwegian, under development, concealed under the aft deck), OTO Breda 76 mm gun and Mistral SAM (on the top of the superstructure, aft of the bridge). The engi ne layout consists of (for the prototype) 2 Allison KF571 turbines, 2 alternative slow speed engines and 2 fan engines. The vessel is characterized as a 4th generation SES design.

The main missions of the FPB has traditionally been littoral warfare – protecting Norwegian waters from an amphibious invasion force. This has traditionally been performed by fast and flexible platforms that are able to exploit their size and manoeuvrability in the skerries. The Skjold improves this tradition by having a very low visual, IR and radar signature, and by having a very high speed and manoeuvre capability. The Skjold has enhanced this by adding increased seakeeping performance, and sustained speed in heavy sea state. This enables the Skjold to operate additionally as a corvette with regard to certain missions/tasks. These capabilities allows the Skjold to operate for sustained periods in more open waters from the coastline - broadening the spectre of operations from war to peacekeeping and crisis. The onboard capacities with regard to both technology and crew fatigue represents less dependence of logistics and bases, utilizing an increased capability to operate for sustained periods in out of area operations. The main potential missions/tasks for the Skjold class FPB when operating nationally or as part of an international force may be: Off coast and littoral sea control/denial operations: § Support to protection of SLOC § Support to protection of offshore installations § Territorial anti-invasion

Surveillance and territorial jurisdiction: § Surveillance § Territorial sovereignty § Anti immigration/smuggling/illegal cargo

Military Interdiction Operations: § Surveillance § Embargo/blockade § Anti immigration/smuggling/illegal cargo

Power projection: § Advanced force sea control ops in the littorals from the sea



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§ Sea control support to amphibious forces in the littorals § Naval gunfire support

SOF: § Covert exfil/infil

Army support: § Support to protection of tactical/operational army transfer by sea § Naval gunfire Support

The Skjold would, if designed today, probably have been built and classed according to DNV Naval Class.



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Visby Corvette: The Visby Class Corvette is a multipurpose combat ship with 600 tonnes displacement. The hull is a sandwich construction of a PVC core with carbon fiber/vinyl laminate. The propulsion system consists of two identical CODOG machinery systems, each driving a KaMeWa 125 size WaterJet Unit. The ship has reduced signatures, i.e. Radar -, Hydro acoustics-, IR- and Magnetic. The High Speed Machinery is twin Honeywell TF50A Gas Turbines, cantilever mounted side by side on the Main Reduction Gearbox housing. The Main Reduction Gearbox is a dual input high performance marine Gearbox designated MA -107 SBS, designed and manufactured by Cincinnati Gear Co. The Low Speed Machinery is a MTU 16 V 2000 TE90 Diesel Engine connected to the MRG by a power take off shaft. Combustion Air for the Gas Turbines is ducted from the shipside Air Inlet Screen (radar screen) via 3-stage separating filters. The Exhausts from the twin Gas Turbines are combined into one Exhaust Pipe and ducted to the ship transom above the WaterJet stream. Very little can be changed in the Gas Turbine, but high quality such as well balanced rotating part contributes to reduce the signatures. However, the main work has to be accomplished by the building shipyard in cooperation with the Gas Turbine manufacturer. The Main Reduction Gearbox is more available for changes to reduce signatures, but even for the Gearbox the building shipyard has to take design and ins tallation measures. The HSM installation consist mainly of the Gas Turbine Engine, the Main Reduction Gear, WaterJets Unit and surrounding equipment such as main shaft, bearings and so on. The multi-role Visby class corvette ships can carry out a range of missions:

- Mine Counter Measures - Anti Submarine Warfare - Mine Laying - Surface Combat - Underwater Defense - Air Defense - Patrol service and escort duties

The Visby class corvette main data are as follows: Length over all: Approx. 72 m Length between perpendiculars: 61,5 m Width: Max. 10,4 m Displacement, fully equipped: Approx. 600 tonnes Draft: Approx. 2,5 m Crew: 43 Hull: CFRP-sandwich High speed machinery: 4 Gas Turbines, total approx. 16 000 kW Low speed machinery: 2 Diesel Engines, total approx. 2 600 kW Propulsion: 2 WaterJet Propulsion units Generators: Generators, total approx. 810 kW



273



274

Description of the Canadian MCDVs for the NATO NG/6 Specialist Team - Small Ship Design

Project: Standards Used in Small Ship Design Canada MCDV

HMCS Kingston (MCDV 700) Brief Description of the Role of the Canadian MCDVs The MCDV is a Multipurpose offshore patrol and route surveillance mine countermeasures ship, intended to combine the roles of offshore patrol vessel, training ship, coastal defense, and route surveillance and mine clearance into one platform. The MCDVs were designed and built to commercial standards, although some key areas such as stability, flood control, maneuverability and ammunition storage are built to military specifications. The ships are very flexible -- inter-changeable modular payloads can be fitted for route survey, bottom object inspection and minesweeping. (If required additional accommodations can also be fitted). KINGSTON Class ships are crewed primarily by Naval Reservists. MCDVs offer an economical alternative to major surface units for routine but nevertheless important patrolling duties, as these are vital in maintaining Canadian sovereignty and protecting Canada's shores. The ships' design accommodates four primary modular payloads: an additional accommodation module for increased training capacity, a mechanical minesweeping system (MMS), a route survey system, and a bottom object inspection vehicle. These can be on- or off-loaded within 12 hours. During Route Survey tasks, the ships deploy a partially controllable "fish" fitted with a side scan sonar. This towed system creates imagery and a database of the condition and objects on the seabed for subsequent investigation. The database can later be used during mine hunting tasks for example, to



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avoid investigating previously located and known objects. A remote operating vehicle (bottom object inspection) can also be deployed to closely investigate objects that have been observed. If the ship were to be constructed today a combination of Classification Society and Government Specifications similar to the original build would be used.

Ship Characteristics Length Between Perpendiculars (LBP) Length Overall (LOA) Molded Beam at Waterline (BWL) Maximum Beam (Bmax)

49,00 m 55,31 m 10,76 m 11,30 m

Draft (Payload Dependant)

Molded Deep Draft at Location

Payload

Coastal Surveillance Mine Sweeping Route Survey Mine Inspection

Amidships

3,03 m 3,08 m 3,04 m 3,05 m

Navigational - Aft 3,24 m 3,42 m 3,33 m 3,27 m

Molded Depth to Weatherdeck (Amidships) 7,5 m Height Above Operating Light Ship Waterline

Load Condition

Operational Light Ship Deep Departure

Height 23,6 m 23,6 m

Displacement (Payload Dependant) Payload

Coastal Surveillance Mine Sweeping Route Survey Mine Inspection

Operational Light Ship

834,09 tonne 868,05 tonne 847,82 tonne 841,62 tonne

Deep Departure 941,27 tonne 975,23 tonne 955,00 tonne 948,80 tonne

Propulsion 2 Azimuthing Thrusters with Fixed Pitch Propellers Driven by 2 Electric Motors 4 - 2450 hp (1827 kW) drive 2 – 3000 hp (2237 kW) Electric Generators to power the ship and propulsion Self Defense 1 – Bofors 40mm Anti-Aircraft Gun 2 – 50 calibre machine guns Small Arms Crew Officers 8 Senior NCM 11 Junior NCM 18 Total 37



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ITALIAN NAVY

NEW PATROL SHIP “SIRIO CLASS” (NUPA)

MAIN CHARACTERISTICS

§ FULL-LOAD DISPLACEMENT 1540 tonne

§ LENGTH O.A. 88.6 mt

§ LENGTH B.P. 80 mt

§ BEAM MOLDED 12.2 mt

§ DEPTH (MAIN DECK) 8.2 mt

§ MAXIMUM SPEED (FULL -LOAD CONDITION) 22 knots

§ ACCOMMODATION 70

§ RANGE AT 17 KNOTS 3300 n.m.

§ MISSION ENDURANCE 10 days

PROPULSION PLANT

§ 2 DIESEL ENGINES GMT WARTSILA W12V26XN MAXIMUM CONTINUOUS RATINGS 2x

4320 Kw

§ 2 REDUCTION GEARS

§ 2 INDEPENDENT SHAFTS

§ 2 FEATHERING C.P.P.

ELECTRIC PLANT

§ 2 DIESEL GENERATORS ISOTTA FRASCHINI 1708 T2ME

§ POWER 3x600 kW (at 1500 r.p.m.)

§ PRIMARY POWER 380 V – 50 Hz



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MAIN OPERATIONAL TASK

§ PATROLLING & SURVEILLANCE

§ ANTI SMUGGLING AND ANTI IMMIGRATION

§ INTERDICTION

§ POLLUTION CONTROL

§ POLLUTION OIL RECOVERY

§ DISPERSION BY CHEMICAL SPRAYING

§ FIRE FIGHTING

§ S.A.R. MISSIONS

§ DIVING SUPPORT

The ships will be commissioned during the 2003. If the project were started now, the Italian Navy would follow the new Rules for Naval Ves sel

(RINAMIL) that have been developed by the Italian Navy and the Italian Register R.I.Na. We have also a new publication “Habitability Onboard the Ships of the Italian Navy” (SMM100 ed.

2003). Many of the new habitability rules have been used in the design phase of the Sirio class.



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ROYAL NETHERLANDS ANTILIES COAST GUARD CUTTER



279

General Yard no. : 5103, 5104 en 5105 Basic functions : Coast Guard Patrol and S.A.R.

operations in the E.E.Z. of the Netherlands Antilles and Aruba

Hull material : steel, Lloyd's grade A Superstructure : aluminium - AA 5083 and 6082 Classification : Netherlands Shipping Inspection

and Lloyd's -I< 100 Al, SSC, Patrol, Mono, HSC, G5, LMC, UMS

Nautical, surveillance and communication equipment (optional) Radar : Signaal Scout - surveillance

Kelvin Hughes - navigation Optical equipment: low level light binoculars Gyro / auto-pilot : C. Plath Speedlog : C. Plath GMDSS : Radio Holland Armament Armament : 12 .7 LMG and hand weapon

Dimensions Length o .a. : 42.80 mtr Beam o .a. : 6.71 mtr Draft (propeller) : 2.52 mtr Capacities Crew : 11 + 6 + 2 persons Fuel : 27,153 Itr Water : 6,380 Itr with freshwater maker Range : 2,000 n .m . at 12 kn . standard

600 n .m . at 23 kn . in sea state 4 3,000 n .m . at 12 kn . with optional spare capacity

Endurance : 7 days at sea Performance Speed : 23 kn . i n sea state 4 with Bf 5

26 .5 kn . (trial conditions) Operations : 3,000 - 4,000 hours per year Electrical equipm ent Networks: 440V - 60Hz / 115V - 60Hz / 24V d .c . Generator sets: 2x Cel 3304B DI-T / 2x 131 kVA 1800rpm Propulsion system Main engines : 2x Caterpillar 3516B DI-TA elec Propellers : 2x Lips controllable pitch props Gearboxes : 2x Reintjes, reduction 3.5:1 Deck lay-out Anchor equipment : 1x 196kg H .H .P. 16mm U2 chain 140mtr Fendering : rubber/ PE, 150x150 mm Slipway in aft ship : hydraulically operated transom door Tenders : 7mtr R.I .B. with in-board

diesel /water jet, speed 30 kn. with a crew of 6 3 .80mtr MOB with out-board motor 25Hp

Crane : electric crane for tender and stores Auxiliary systems Bow thruster : Promac Fresh water maker: Promac Sewage system : Quavac Fuel separator : Facet FiFi system : Ajax, with water/foam monitors Miscellaneous : Gas detection and gas tight accommodation



280

POLISH NAVY

MINEHUNTER 257 CLASS „KORMORAN”

1. MAIN CHARACTERISTICS

• FULL-LOAD DISPLACEMENT 600 – 700 t • LENGTH O..A. 55,0 m • BEAM 10,0 m • DEPTH (MAIN DECK) 5,0 m • SPEED MAX/ECONOM. 15,0 / 12,0 knots • ACCOMMODATION 45 • RANGE AT 12 KNOTS 2500 n.m. • MISSION ENDURANCE 14 days

2. PROPULSION PLANT

• 2 DIESEL ENGINES MTU 2 x 1000 kW • 2 REDUCTION GEARS • 2 INDEPENDENT SHAFTS • 2 PROPELLERS VOITH – SCHNEIDER

3. ELECTRICAL PLANT

• 3 DIESEL GENERATORS MTU • POWER 3 x 300 kW • PRIMARY POWER 450 V – 60 Hz

4. MAIN OPERATIONALS TASKS

• MCM ON FAIRWAYS AND ASSIGNED AREAS OF THE SEA • DETERMINE THE BOUNDARIES OF THE MINED AREA • CLEARING OF THE ROUTS THROUGH THE MINED AREA • SEEKING AND IDENTIFICATION OF THE SEA MINES • MINEHUNTING OF BOTTOMED AND MOORED MINES • CO-OPERATION WITH OTHER OWN AND NATO FORCES



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• MCM PROTECTION OF THE COMBAT AND TRANSPORT SHIPS AT SEA • CLOSE COMBAT PATROL • SEARCHING AND FIGHTING UNDERWATER DEMOLITION FORCES AND

MINES • PARTICIPATION IN SEARCH AND RESCUE MISSIONS

Designing process of minehunter 257 class has been started in 1999 by Naval Shipyard Gdynia with closed international co-operation with German Shipyards Lürssen , Abeking & Rasmussen and Spanish Shipyard BAZAN according to the Modernization Program of Polish Navy Forces up to 2012. The prototype should be built in 2008. Ship is designing on base of Rules of Germanischer Lloyd, German Navy Standards, Polish Register of Shipping, Polish Navy Standards and NATO Standards – STANAGs. Hull will be displacement type with non -magnetizable steel kind 1.3964.9.



UK River Class OPV FOPV - PRINCIPAL PARTICULARS KEY DIMENSIONS

Length OA 79.5m Length BP 73.6m Beam molded 13.6m Depth molded to no.2 deck 7.0m Depth molded to no.1 deck 9.6m Maximum draft 4.15m Maximum displacement 2065t

CLASSIFICATION / CERTIFICATION

Classification DNV Rules for Classification of High Speed Light Craft and Naval Surface Craft

Class notation + 1A1 LC Patrol EO NAUT-C 7TEU CLEAN ERS Flag Authority reqt’s

‘Capable’ of being registered in the UK by the MCA as a Class VII Cargo Vessel, as modified by the IMO Code of Safety for Special Purpose Ships with less then 50 Special Personnel

PERFORMANCE

Max speed 20.5 kts Range at 12 knots 5500nm Endurance 21 days

ACCOMMODATION Normal crew complement - 28 (1xCO, 5xOfficers, 5xSR’s, 17xJR’s) plus 8 trainees as required.

Cabins Berths Single berth Officers suites including dayroom 2 2 Single berth Officers cabins 2 2 Twin berth Officers cabins 4 8 Twin berth SR’s cabins 7 14 Twin berth JR’s cabins 11 22

Total cabins 26 48 PROPULSION SYSTEM

2 x 12V RK270 Rushton Marine Diesel Engine 2 x 5 bladed high skew inward rotating CP props Bow thruster tunnel and drive - 280MW thruster motor with fixed pitch propellers, 30kWe controller/shore supply converter.

ELECTRICAL SYSTEM

3 x 250kW Caterpillar diesel generators providing main electrical supply, 450 volts 3 phase 60hz. 1 x 170kW Caterpillar emergency diesel generator

ARMAMENT

1 x 20mm Gun 2 x GPMG 7.62mm



283

U.S. Coast Guard Famous Class Cutter

Displacement: 1,820 long tons, Full Load Dimensions: Length – 270 ft LOA Beam – 38 ft Draft – 14 ft Complement: 100 (14 Officers) Speed: Maximum - 19.5 knots Most Economic – 12 knots Range: 3800 nautical miles at max speed Main Machinery: 2 Alco 18V-25-1 diesels: 7,290 hp, 2 shafts; Controllable Pitch Propellers Helicopter: HH-65A or HH-60J Guns: 1- OTO Melara 76 mm/62 Mk 75; 2 – 12.7 mm machine Guns or 2 – 40 mm Mk19 grenade launchers Radars: Surface Search - SPS-73; Fire Control – Sperry Mk 92 Mod 1; Tacan – URN 25



Ukrainian Navy Corvette of "Grisha-V" Class

Main particulars Weapons Length overall 71,1 m Beam, overall 10,3 m Draught on design WL 3,54 m Displacement, standard/full 876/1030 t

1x2 SAM "OSA-MA" 1 – 76 mm AK-176 Gun mounting 1-6x30mm AK-630M Gun mounting 2x2, 533mm Torpedo launchers 1x12 ASW system RBU-6000 4, PK-10 Decoy/Chaff launchers 18 mines or 12 depth-bombs

Propulsion /maximum speed Complement CODAG 32 kts Range 2500 NM at 14 kts Endurance : 9 days

89 (9 officers)

Radio-electronic equipment & Communications

3D Air/surface search radar

Navigational radar SAM FCS Gun FCS

Sonar ESM IFF

C2 system External and internal communication system



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Offshore Patrol Vessel (Dst=890 t) proposed for the Ukrainian Coast Guard

Main particulars Length overall 73,70 m Length on design WL 67,00 m Beam overall 10,95 m Draught on design WL 2,70 m Depth on upper deck 7,70 m

Displacement, standard/full 890/960 t Material of hull and superstructure high-grade shipbuilding steel

Propulsion / maximum speed

Weapons

2, MTU diesels 21+ kts Range 3800 nm at 12 kts Endurance 15 days

1x76-mm Ak-176 Gun mounting 1-6x30-mm AK-630M Gun mounting

Complement/Accommodation

Special equipment

56 (9 officers) – in double- and quadruple-berthed cabins with all conveniences

Six-seater fast examination craft

Communication

Sensors

Integrated external and internal communication system

Fire Control radar / EO tracker IFF 2, Surface search and navigation radars



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APPENDIX 9.7

SPECIFICATION TEMPLATE



287

PART I PERFORMANCE SPECIFICATION

1.0. Program Requirements 1.1 Scope -

a. Describes the total ship, its systems, and equipment in terms of required/desired performance

b. Provides requirements for verification of performance c. Provides all ship interface requirements d. Describes the environment in which the ship must operate e. Provides electronic “links” to design guidance documents f. Provides lessons learned, background and guidance for a better understanding of

selected performance requirements.

1.2 System Description – All the equipment, crew, computer systems, shore infrastructure etc. support the ship, in port and at sea, and all the Navy, joint service, national and NATO system interfaces for execution of its operational mission.

1.3 Schedule –

Outlines schedule for design and construction completion. 1.4 Budget / Cost

Outlines budget and cost goals and milestones. 1.5 Supporting Analyses Required

Describes any other supporting analyses not covered elsewhere. 1.6 Procurement Strategy

Describes process by which vessel(s) will be acquired.

2.0. Applicable Documents 2.1 General –

Lists all applicable documents not listed in other subsections 2.2 Government Documents

2.2.1 Specifications Standards and Handbooks – List of applicable Standards and Handbooks 2.2.2 Other Government Documents, Drawings, and Publications – List of other Government documents

2.3 Non-Government Documents – Provides the List of document(s)of the exact revision to form a part of this specification to the extent specified herein.

2.4 Order of Precedence – Defines in the event of a conflict between the text of this specification and the references cited which document takes precedence. Nothing in this specification, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

2.5 International Conventions and Regulations / Laws and Treaties

Describes vessel compliance with International conventions, regulations, laws, and treaties.

3.0 General Mission Requirements 3.1 Primary Mission(s)

Outlines Primary mission requirements 3.2 Secondary Mission(s)

Outlines Secondary mission requirements 3.3 Emergency Support Requirements

Outlines Emergency Support requirements 3.4 Area of Operations



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Defines Area of Operations 3.5 Philosophy of Operations 3.5.1 Plan for use Defines the intended use of the vessel depicted in the profiles listed below 3.5.2 Operational Profile

Defines the ship’s overall operational profile, including ship schedule sufficient to fully describe the operations of the ship, availability periods for maintenance, training, etc.

3.5.3 Wartime Profile Defines the ship’s wartime mission scenarios and description of wartime operating

conditions and missions, readiness, utilization and speed-time distribution 3.5.4 Peacetime Profile

Defines the ship’s peacetime mission scenarios and description of peacetime operating conditions and missions, readiness, utilization and speed-time distribution

4.0. General Operational Requirements

4.1 Environmental Conditions Defines Environmental requirements and limits

4.1.1. Atmospheric Environment Defines Temperature, humidity, solar radiation, moisture, and pressure limits under which

the vessel must operate. 4.1.2. Sea Conditions

Defines limits due to Sea State, etc. 4.1.3. Sea Water Temperature –

The ship shall be capable of performing its missions in seawater temperatures of _____degrees C minimum to _____ degrees C maximum.

4.1.4 Ice and Snow Ship structure and exposed systems shall be capable of operating in ice-covered

waters as follows ________. Exposed systems and equipment shall be design to start and operate properly when covered with an ice load of ______. 4.1.5 Impact, vibration, noise 4.1.6 Electrical environment and lightning protection

4.1.7 Electromagnetic environment

4.2 Hydrodynamics (Mobility) 4.2.1 General Generic Mobility requirements, not listed in other subsections 4.2.2 Seakeeping Performance –

Maximum pitch angle, pitch amplitude, roll angle, and roll amplitude. Absolute vertical acceleration at the bow and the bridge, relative vertical motion at the bow and vertical velocity at the helicopter platform.

4.2.3 Speed / Power Describes minimum speed and powering requirements, including endurance.

4.2.4 Maneuverability Defines maneuverability requirements, including turning diameter, turning rate,

directional stability and controllability, stopping, low speed heading and lateral control, station keeping and track keeping.

4.2.5 Accessibility Defines drafts, canal transit requirements, dry dock capability, and height constraints.

4.3 War-fighting Capability

4.3.1 General Defines general war-fighting requirements not listed in other subsections.

4.3.2 Power Projection Capabilities Describes requirements for Power Projection systems.

4.3.3 Defensive Capabilities



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Describes requirements for Defensive systems. 4.3.4 Reconnaissance / Surveillance Capabilities

Describes Reconnaissance / Surveillance requirements. 4.3.5 Support Capabilities

Describes requirements for war-fighting support. 4.3.6 Anti-terrorism Capabilities

Describes the requirements for countering a terrorist threat.

4.4 Total Ship Survivability – Defines the hostile environments, protection requirements from attack by threat weapons, and acceptable capability degradation. 4.4.1 Survivability Approach – Addresses total ship approach to survivability, which addresses susceptibility, vulnerability, and recoverability. 4.4.2 Survivability Requirements – Address the survivability requirements in accordance with ______ 4.4.3 Threat – Addresses the capability of countering threats within the context of defined mission scenarios and engagements. 4.4.4 Vulnerability – Addresses the built-in capability to withstand threat weapons damage, peacetime accidents and flight operations-related accidents. 4.4.5 Recoverability – Defines the capability to control the spread of damage, minimize crew casualties and restore the ship to mission capable status following damage.

4.5 Signature Management Describes requirements for the following:

4.5.1 Radar Cross-Section 4.5.2 Infrared Signature 4.5.3 Acoustic Signature 4.5.4 Magnetic Signature 4.5.5 Optical Signature 4.5.6 Wake 4.5.7 Electromagnetic Emissions 4.5.8 Pressure Signature 4.5.9 Other Signatures

4.6 Stability 4.6.1 General 4.6.2 Reserve Buoyancy

The ship shall have reserve buoyancy in accordance with ____. 4.6.3 Intact Stability –

The ship shall have intact static stability performance in accordance with ____.

4.6.4 Damage Stability The ship shall have damage stability performance in accordance with

____. 4.6.5 Weight Control –

The ship shall have a minimum future growth margin of ___ % of Condition ____ weight. The longitudinal center of gravity of future growth margin shall be estimated.



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4.7 Human System Integration 4.7.1 Human Engineering

Human Engineering Principles and Standards shall be applied throughout the ship design, system and equipment selection, hardware and software design, and human machine interfaces.

4.7.2 Manning Defines maximum crew size and use of automation.

4.7.3 System Safety 4.7.4 Habitability

Defines habitability requirements. 4.7.5 Human Safety

4.8 Reliability, Availability, Maintainability (RAM) 4.8.1 Reliability

Defines Reliability requirements to prevent mission degrading failure 4.8.2 Availability

Defines Availability requirements to prevent mission degrading failure 4.8.3 Maintainability

Defines Maintainability requirements to prevent mission degrading failure

4.9 Logistics and Readiness 4.9.1 Sustainability

Defines design requirements for sustainability of the ship. 4.9.2 Supportability

Defines Supportability design requirements 4.9.3 Supply Support

Describes Supply support equipment and design requirements. 4.9.4 Environmental Planning, Compliance

Requirements for environmental design issues and compliance 4.9.5 Battle / Peacekeeping Support Force Interoperability

Communications, Command, and Control centers shall be fully compatible with other naval, expeditionary, joint, combined, and interagency forces

4.9.6 Shipboard Integration and Interoperability Requirements for monitoring and automated control systems

4.9.7 Logistics 4.9.8 Personnel and Training 4.9.9 Functional Area Characteristics 4.9.10 Precedence 4.9.11 Integrated Quality Assurance Provisions



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Part II General Technical Specification 000 GENERAL GUIDANCE AND ADMINISTRATION This section outlines general requirements for ship system performance and includes

related general requirements for planning, development, design, construction and documentation associated with acquisition and maintenance.

042 GENERAL ADMINISTRATIVE REQUIREMENTS This section describes the general administrative and technical requirements and

information defining the work and responsibilities required for the design and construction of the ship.

045 CARE OF SHIP DURING CONSTRUCTION This section describes the requirements for maintaining and protecting the ship and

its structure, equipment, outfit. etc., during construction. This includes requirements for protecting the ship from fire and flooding.

050 SHIP SYSTEM PERFORMANCE This section addresses desired performance capabilities of the ship including: ship

readiness, endurance, maneuverability, noise characteristics, operational replenishment, speed and reaction time.

070 GENERAL REQUIREMENTS FOR DESIGN AND CONSTRUCTION

This section sets forth requirements for the design and construction of the ship including: principle characteristics (e.g. length, draft, displacement) size of crew, number of accommodations, regulatory body certificates, classification society notation, ballistic protection, biological and chemical protection, equipment requirements, fire protection requirements, mass properties and stability limits, mass properties margins, deck area margins, principal watertight features and vital spaces. In addition this section identifies the standards governing the design, construction, workmanship and installation of components for the ship. Where specific requirements are stated elsewhere in the specification, they shall take precedence over requirements stated in this section.

071 ACCESS This section describes the requirements for passageways and openings required for

normal and emergency access and egress throughout the interior and exterior of the ship.

072 SURVIVABILITY This section provides ship system level survivability requirements. This includes

requirements for vulnerability (i.e. blast, fragmentation, shock, electromagnetic pulse, and chemical, biological and radiological) and susceptibility and observability (radiated noise, infrared, electromagnetic radiation, magnetic signature, radar cross-section, wake and visual).

073 NOISE AND VIBRATION This section discusses ship specific methods for meeting the noise and vibration

criteria defined in the performance specification. Included in this section are requirements for resilient mountings, distributed isolation material and flexible steel supports.

074 CASTING, WELDING, RIVETING, ALLIED PROCESSES This section includes requirements for castings, welding, forging, structural

mechanical fastening, brazing and allied processes for associated inspection to ensure quality and reliability of ship structure and machinery fabrication.

075 THREADED FASTENERS STANDARDS This section defines threaded fastener requirements applicable to assembled joints

and attachment machinery and components to their foundation or to hull structure. 076 RELIABILITY AND MAINTAINABILITY This section defines the reliability and maintainability (R&M) program requirements

including; Tasks, Program Plan, Risk Assessment, Design Requirements, Design



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Criteria, Analysis, Testing, Data Collection, Failure Analysis and Corrective Action. 077 SAFETY This section identifies safety design requirements, system safety program

requirements, safety design precedence and required technical documentation. 078 MATERIALS This section identifies the criteria for material selection, use and corrosion prevention

and control, and covers the required standards of design, materials corrosion, workmanship, installation and inspection.

079 SEAWORTHINESS This section addresses damage control, watertight integrity, and stability. 080 INTEGRATED LOGISTIC SUPPORT REQUIREMENTS This section sets forth the general requirements for Integrated Logistics Support

(ILS), including the requirements for an ILS program, the establishment of configuration baselines, logistic support analysis requirements, and training.

081 MAINTENANCE This section sets forth the maintenance philosophy for the ship and maintenance

requirements the ship, systems, components and equipment shall be designed to. 082 SUPPORT AND TEST EQUIPMENT 083 SUPPLY SUPPORT This section sets forth the requirements for performing work and providing data and

material for the development of supply support system. This includes Provisioning Technical Documentation development, provisioning monitoring, allowance development and outfitting the ship.

084 PACKAGING, HANDLING, STORAGE AND TRANSPORTATION This section sets forth the requirements for preservation-packaging, packaging and

marking for stowage both hazardous and non-hazardous materials; requirements for on-site stowage (shipyard) and warehousing of material and shipping and transportation requirements.

085 ENGINEERING DRAWINGS This section identifies the drawings to be prepared in support of the ship’s

construction and sets forth general drawing requirements including format and size, symbology and drawing scale. Supplementary unique requirements are contained in other sections of this specification.

086 TECHNICAL MANUALS This section identifies the technical publications and related management data items

to be prepared as part of the ship construction contract. This section also presents the requirements for the preparation of these publications and data items.

088 MANPOWER AND PERSONNEL This section addresses manning requirements including ranks, rates and skill levels. 089 TRAINING AND TRAINING SUPPORT This section addresses training equipment and facilities including instrument aids,

learners’ aids, models and mockups, textbooks, computers and visual aids. 090 QUALITY ASSURANCE This section addresses requirements for the shipbuilders quality assurance program. 091 SHIP INSPECTIONS This section sets forth requirements for the development of test documentation and

the management and implementation of the ship inspection program. 092 SHIP TESTS This section sets forth requirements for the development of test documentation and

the management and implementation of the ship test program. The requirements of this section are supplemented by specific test requirements in Section 095.

093 COMBAT SYSTEMS CHECKOUT This section sets forth the requirements for command and control testing,

consolidated operability tests, qualification firings alignment and weapons system acceptance tests.

094 REGULAR SHIP TRIALS



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This section sets forth general requirements for trials that are the responsibility of the shipbuilder and those trials that will be accomplished by the government.

095 WHOLE SHIP TESTING This section contains specific testing and test procedure requirements for the

shipboard test program. Test requirements are specified for equipment and systems. 096 MASS PROPERTIES CONTROL This section defines requirements for determining and reporting the weight of the

ship and identifies requirements for controlling weight growth during the design and construction process.

097 INCLINING EXPERIMENT This section defines requirements for determining and documenting the centers of

gravity and displacement of the vessel once construction is complete. 098 MODELS AND MOCKUPS This section sets for the requirements for constructing models and mockups used to

study space, shape, arrangement, installation sequence, interference, lines of sight, arcs of fire, human factors, hydrodynamic performance, functional operability and for instruction.

099 PHOTOGRAPHS This section sets for the requirements for photographs to be taken during

construction of the ship.



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100 HULL STRUCTURE, GENERAL This section sets forth the general requirements for the design and construction of

the cutter’s structure, including the hull and all structural components. The requirements that are particular to each structural component are provided in applicable sections.

101 GENERAL ARRANGEMENT-STRUCTURAL DRAWINGS 110 SHELL AND SUPPORTING STRUCTURE 111 SHELL PLATING This section sets for the requirements for the design and construction of the shell

plating of the ship. 113 INNER BOTTOM This section sets forth the requirements for the design and construction of the inner

bottom of the ship. 114 SHELL APPENDAGES This section sets forth the requirements for the design and construction of the bilge

keels, shaft fairwaters, skegs and other appendages of the ship. 115 STANCHIONS This section sets forth the requirements for the design and construction of the

stanchions. 116 LONGITUDINAL FRAMING This section sets forth the requirements for the design and construction of the

longitudinal framing of the ship. 117 TRANSVERSE FRAMING This section sets forth the requirements for the design and construction of the

transverse framing of the ship. 119 LIFT SYSTEM FLEXIBLE SKIRTS AND SEALS This section sets forth the requirements for the design and construction of the flexible

seals, longitudinal seals, semi-flexible seals, stability seals, transverse seals, flexible skirts and air bag valves.

120 HULL STRUCTURAL BULKHEADS This section sets forth the requirements for the design and construction of the

structural bulkheads below the superstructure. 121 LONGITUDINAL STRUCTURAL BULKHEADS This section sets forth the requirements for the design and construction of the

longitudinal structural bulkheads. 122 TRANSVERSE STRUCTURAL BULKHEADS This section sets forth the requirements for the design and construction of the

transverse structural bulkheads. 123 TRUNKS AND ENCLOSURES This section sets forth the requirements for the design and construction of access

trunks (e.g. ammunition, cargo, escape, fan room) and built in tanks. 130 HULL DECKS This section sets forth the requirements for the design and construction of decks

below the superstructure. 140 HULL PLATFORMS AND FLATS This section sets forth the requirements for the design and construction of platforms

and flats below the superstructure. 150 DECK HOUSE STRUCTURE This section sets forth the requirements for the design and construction of the deck

house and superstructure bulkheads, decks, expansion joints, structural stanchions and bulwarks.

160 SPECIAL STRUCTURES 161 STRUCTURAL CASTINGS, FORGINGS, AND EQUIV. WELDMENTS This section includes the requirements for the design and construction of anchor

stowage flanges, bellmouths, borings, castings, chain pipe and stiffeners, forgings,



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hawse pipes, lifts pads, rudder bearing trunk, shaft struts, shell bolster 162 STACKS AND MACKS (COMBINED STACK AND MAST) This section sets forth the requirements for the design and construction of stacks and

macks including; coverings, forgings, gratings, louvers, ladders, plating, rails and shaping.

163 SEA CHESTS This section sets forth the requirements for the design and construction of sea

chests. 164 BALLISTIC PLATING This section sets forth the requirements for the design and construction of ballistic

plating including; side belt plating, splinter plating and armor grating. 165 SONAR DOMES This section sets forth the requirements for the design and construction of sonar

domes. 166 SPONSONS This section sets forth the requirements for the design and construction of sponsons,

including; mooring sponsons, gun and missile sponsons, and fueling and replenishment at sea sponsons.

167 HULL STRUCTURAL CLOSURES This section sets forth the requirements for the design and construction of hull

structural closures including; doors, airport cover plates, closing devices, hatches, locking rings and manholes.

168 DECKHOUSE STRUCTURAL CLOSURES This section sets forth the requirements for the design and construction of deckhouse

structural closures including; doors, airport cover plates, closing devices, hatches, locking rings and manholes.

169 SPECIAL PURPOSE CLOSURES AND STRUCTURES This section sets for the requirements for the design and construction of special

purpose closures and structures; including bow doors, cargo hatch covers, gates, hangar doors, hangar hatch covers, metal curtains, ramps, tracks and weapon strike down hatch covers.

170 MASTS, KINGPOSTS, AND SERVICE PLATFORMS This section sets forth the requirements for the design and construction of masts,

kingposts and service platforms. 180 FOUNDATIONS This section sets forth the general requirements for the design and construction of

foundations. If specific guidance is needed this section may be supplemented with additional requirements in groups 181-187.

181 HULL STRUCTURE FOUNDATIONS This section sets forth requirements for hull structure foundations. 182 PROPULSION PLANT FOUNDATIONS This section sets forth requirements for propulsion system foundations. 183 ELECTRIC PLANT FOUNDATIONS This section sets forth requirements for electric plant foundations. 184 COMMAND AND SURVEILLANCE FOUNDATIONS This section sets forth requirements for command and surveillance system

foundations. 185 AUXILIARY SYSTEMS FOUNDATIONS This section sets forth requirements for auxiliary system foundations. 186 OUTFIT AND FURNISHINGS FOUNDATIONS This section sets forth requirements for outfit and furnishing foundations. 187 ARMAMENT FOUNDATIONS This section sets forth requirements for armament foundations. 190 SPECIAL PURPOSE SYSTEMS This section sets forth requirements for the design and construction of special

purpose systems.



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191 BALLAST, FIXED OR FLUID, AND BUOYANCY UNITS This section sets forth requirements for the design and installation of solid ballast and

locked-in liquid ballast. 192 COMPARTMENT TESTING This section sets forth requirements for the testing and inspection of structural

compartments and tanks. 198 FREE FLOODING LIQUIDS This section is used for weight estimating only. 199 HULL REPAIR PARTS AND SPECIAL TOOLS This section sets forth requirements for special tools and handling gear used to

service and repair the hull and its components.



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200 PROPULSION PLANT, GENERAL This section addresses general requirements for the propulsion plant including

propulsion units, propulsion auxiliaries, associated equipment, control systems, piping systems, and electrical systems that are required to drive the propellers.

201 GENERAL ARRANGEMENT - PROPULSION DRAWINGS 202 MACHINERY PLANT CENTRAL CONTROL SYSTEMS This section addresses functional requirements for the central control systems,

control consoles and control and monitoring systems. 220 ENERGY GENERATING SYSTEM This section addresses requirements for components installed as primary propulsive

power but which in themselves do not impart the propelling motion to the ship. When the source of power imparts the propelling force, such as a diesel engine, it belongs in section 230.

223 MAIN PROPULSION BATTERIES This section sets forth requirements for main propulsion batteries. 224 MAIN PROPULSION FUEL CELLS This section sets forth requirements for main propulsion fuel cells. 230 PROPULSION UNITS This section addresses requirements for the prime movers including self-contained

subsystems for air cushion vehicles and surface effect ships. 233 PROPULSION INTERNAL COMBUSTION ENGINES This section addresses requirements for diesel engines, gasoline engines, internal

combustion engines and support equipment integral to these engines. 234 PROPULSION GAS TURBINES This section sets forth the requirements for propulsion gas turbines and internal

parts, and addresses requirements for inspection, removal, repair and installation. 235 ELECTRIC PROPULSION This section sets for the requirements for propulsion generators and all internal parts,

remote control, and indicator and exciter equipments with interconnecting cables and addresses requirements for inspection, removal, repair and installation.

236 SELF-CONTAINED PROPULSION SYSTEMS This section sets forth the requirements for air motors, hydraulic motors, outboard

motors and self contained propulsion systems. 237 AUXILIARY PROPULSION DEVICES This section sets forth the requirements for propulsion motors and associated

equipment including all internal parts, remote control, local and remote indicators and interconnecting cables.

239 EMERGENCY PROPULSION This section sets forth the requirements for emergency propulsion motors, 240 TRANSMISSION AND PROPULSOR SYSTEMS This section addresses requirements for transmission of power from the prime

movers to the propellers. This includes requirements for reduction gears, clutches and couplings, shafting, bearings, propulsors, and lifting system fans and ducts.

241 PROPULSION REDUCTION GEARS This section sets forth the requirements for the main propulsion reduction gears

including integral main thrust bearings and bearing lubrication systems. 242 PROPULSION CLUTCHES AND COUPLINGS This section sets forth the requirements for clutches and couplings for the prime

movers including inlet/outlet air connection of the pneumatic clutch and brake. 243 PROPULSION SHAFTING This section sets forth the requirements for the design and construction of prolusion

shafts including associated equipment, installation, testing and alignment requirements.

244 PROPULSION SHAFT BEARINGS This section sets for the requirements for propulsion shaft supports between



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reduction gear shaft couplings and the propeller. 245 PROPULSORS This section sets forth the requirements for the design and construction of water

propellers, air propellers, cycloidal propellers, controllable pitch hub/blade assembly and control systems, detachable blade propellers and solid cast propellers.

246 PROPULSOR SHROUDS AND DUCTS This section sets forth the requirements for the design and construction of the

propulsors when a shrouded pump jet rotor is utilized. 247 WATERJET PROPULS ORS This section sets forth the requirements for the design and construction of waterjet

propulsors including inlet and outlet ducting, nozzles and waterjet pumps. 248 LIFT SYSTEM FANS AND DUCTING This section sets forth the requirements for the design and construction of lift system

fans including distribution, inlet and outlet ducting. 250 PROPULSION SUPPORT SYS. (EXCEPT FUEL AND LUBE OIL) This section sets forth the general requirements for propulsion support systems

excluding fuel and lube oil. Included is the combustion air system, propulsion control system and uptakes.

251 COMBUSTION AIR SYSTEM This section sets forth requirements for combustion air systems including air filters,

air shutters, expansion joints, forced air induced blowers, intake and discharge duct assemblies, louvers, plenums, screens, silencers, superchargers, trunk and air ducts and water separators.

252 PROPULSION CONTROL SYSTEM This section sets forth requirements for control consoles and equipment required for

machinery control stations. 259 UPTAKES (INNER CASING) This section sets forth requirements for uptakes. 260 PROPULSION SUPPORT SYSTEMS (FUEL AND LUBE OIL) This section sets forth general requirements for propulsion support systems including

fuel service systems and lube oil systems. 261 FUEL SERVICE SYSTEM This section sets forth requirements for components of the fuel service system

including coolers, heaters, pressure regulators, purifiers, strainers and fuel tanks when not built into the hull structure.

262 MAIN PROPULSION LUBE OIL SYSTEM This section sets forth requirements for main propulsion lube oil piping to turbines,

reduction gears, flexible couplings and line shaft bearings. 264 LUBE OIL FILL, TRANSFER, AND PURIFICATION This section sets forth requirements for lube oil fill, transfer and purification piping to

and from purifier supply tanks, discharge sump tanks, sludge tanks, stowage tanks and settling tanks and requirements for purifiers, strainers and transfer pump.

290 SPECIAL PURPOSE SYSTEMS This section sets forth requirements for special purpose propulsion systems. 298 PROPULSION PLANT OPERATING FLUIDS This section sets forth requirements for fluids needed to operate the propulsion plant. 299 PROPULSION PLANT REPAIR PARTS AND SPECIAL TOOLS This section sets forth requirements for all repair parts, replacement items, special

tools and handling gear carried onboard and used to service and repair the propulsion plant.



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300 ELECTRIC PLANT, GENERAL This section addresses general requirements for the electric plant including power

generation, distribution and consuming equipment such as lighting, power, interior communication, weapons, control, electric propulsion, and degaussing installations, the details of which are covered in the following sections of the specification.

301 GENERAL ARRANGEMENT-ELECTRICAL DRAWINGS 302 MOTORS AND ASSOCIATED EQUIPMENT This section sets forth the requirements for electric motors, controllers, brakes and

switches. 303 PROTECTIVE DEVICES This section sets forth the requirements for maximum available short circuit currents,

protection of alternating current power distribution systems, protection of lighting systems, interior communication systems and weapon control systems.

304 ELECTRIC CABLES This section sets forth the requirements for the application, selection, and installation

of electrical cables required for power, lighting, interior communication, weapons control, electronic systems, degaussing systems and electric propulsion systems.

305 ELECTRICAL DESIGNATING AND MARKING This section sets forth the requirements for identifying power, lighting, electronic,

interior communication, fire control, degaussing and other electric equipment circuits and cables.

310 ELECTRIC POWER GENERATION This section sets forth performance requirements, equipment selection, and

installation requirements for ship service and emergency generator sets, batteries and power conversion equipment the details of which are covered in the following sections of the specification.

311 SHIP SERVICE POWER GENERATION This section sets forth requirements for equipment selection, installation, inspection

and testing of ship service generators. This includes the diesel engine, the generator, remote control, indicator and exciter equipments with all interconnecting cables and cables to the power distribution system.

312 EMERGENCY GENERATORS This section sets forth requirements for equipment selection, installation, inspection

and testing of emergency generators. This includes the diesel engine, the generator, remote control, indicator and exciter equipments with all interconnecting cables and cables to the power distribution system.

313 BATTERIES AND SERVICE FACILITIES This section sets forth requirements for batteries and service facilities for non-main

propulsion systems, battery charging equipment, battery trays and hold down devices, portable storage batteries, and spare batteries for mobile equipment.

314 POWER CONVERSION EQUIPMENT This section sets forth requirements for power conversion equipment,

instrumentation and mounting boards, inverters and converters, line voltage regulators, motor generators, rectifiers, and transformers.

320 POWER DISTRIBUTION SYSTEMS This section sets forth the requirements of the ship service power distribution system,

emergency power distribution system, casualty power distribution system, and lighting distribution system.

321 SHIP SERVICE POWER CABLE This section sets forth requirements for bus tie feeders, cables from distribution

switchboards to power panels, cables from load centers to power panels, generator leads, main wireways, power cables, power feeders, ship service power cable and cable reels.

322 EMERGENCY POWER CABLE SYSTEM This section sets forth requirements for emergency power cables from switchboards



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and load centers to casualty power risers. 323 CASUALTY POWER CABLE SYSTEM This section sets forth requirements for casualty power cables from switchboards

and load centers to casualty power risers. 324 SWITCHGEAR AND PANELS This section sets forth requirements for selection and installation of ship service

switchboards, emergency switchboards, degaussing switchboards, load centers, control centers, distribution panels and test panels.

330 LIGHTING SYSTEM This section sets forth general requirements for selection and installation of ship

service and emergency lighting systems, including distribution and control, and application, selection and installation of equipment the details of which are covered in the following sections of the specification.

331 LIGHTING DISTRIBUTION This section sets forth requirements for ship service and emergency lighting

distribution systems including distribution boxes, lighting panels, lighting transformers, ship service lighting distribution cabling and emergency, low voltage and special application lighting distribution cable.

332 LIGHTING FIXTURES This section sets forth requirements for lighting fixtures including fixtures for general

and special illumination and illumination requirements. 340 POWER GENERATION SUPPORT SYSTEMS This section sets forth requirements for power generation support systems. 341 SSDG LUBE OIL This section sets forth requirements for lubrication systems for ship service diesel

generators. 342 DIESEL SUPPORT SYSTEMS This section sets forth requirements for fuel, lube oil, seawater and air piping and

combustion air ducting to diesel engines. 343 TURBINE SUPPORT SYSTEMS This section sets forth requirements for fuel, lube oil, seawater and air piping and

combustion air ducting to gas turbines. 390 SPECIAL PURPOSE SYSTEMS This section sets forth requirements for special purpose power generation systems. 398 ELECTRIC PLANT OPERATING FLUIDS This section sets forth requirements for fluids needed to make electrical systems

operable. 399 ELECTRIC PLANT REPAIR PARTS AND SPECIAL TOOLS This section sets forth requirements for all repair parts, replacement items, special

tools and handling gear carried onboard and used to service and repair the electrical plant.



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400 COMMAND AND SURVEILLANCE, GENERAL 401 GENERAL ARRANGEMENT - COMMAND AND SURVEILLANCE 402 SECURITY REQUIREMENTS This section sets forth security requirements for command and surveillance systems. 403 PERSONNEL SAFETY This section sets forth personnel safety requirements for command and surveillance

systems. 404 RADIO FREQUENCY TRANSMISSION LINES This section sets forth general requirements for radio frequency transmission lines. 405 ANTENNA REQUIREMENTS This section addresses requirements for installation of antennas of communication,

navigation, radar, weapons and special purpose systems. 406 GROUNDING AND BONDING This section sets forth requirements for grounding and bonding of cables used in the

command and surveillance systems. 407 ELECTROMAGNETIC INTERFERENCE REDUCTION (EMI) This section addresses requirements for the routing and shielding of cables and

acceptable limits for EMI. 408 SYSTEM TEST REQUIREMENTS This section sets forth test requirements for command and surveillance systems. 409 COMBAT SYSTEM GENERAL REQUIREMENTS This section sets forth general requirements for the combat system. 410 COMMAND AND CONTROL SYSTEMS This section sets forth general requirements for command and control systems. 411 DATA DISPLAY GROUP This section sets forth requirements for data display equipment including display

consoles, digital data readouts, radar distribution switchboards, azimuth converters and video signal simulators.

412 DATA PROCESSING GROUP This section sets forth requirements for data processing equipment and systems. 413 DIGITAL DATA SWITCHBOARDS This section sets forth requirements for digital data switchboards. 414 INTERFACE EQUIPMENT This section sets forth requirements for interface equipment including analog to

digital converters, central signal data converters, digital to analog converters, integrated key sets and key set central multiplexers.

415 DIGITAL DATA COMMUNICATIONS This section sets forth requirements for digital data communications systems. 417 COMMAND AND CONTROL ANALOG SWITCHBOARDS This section sets forth requirements for command and control analog switchboards. 420 NAVIGATION SYSTEMS This section sets forth general requirements for navigation systems. 421 NON-ELECTRICAL/NON-ELECTRONIC NAVIGATION AIDS This section sets forth requirements for application, selection and installation of non-

electrical/non-electronic navigation aids including compasses, clinometers, chronometers, pelorus, and sextants.

422 ELECTRICAL NAVIGATION AIDS (INCL NAVIG. LIGHTS) This section sets forth requirements for control, application, selection and installation

of navigation lights, searchlights, signal lights and lights for night flight operations. 423 ELECTRONIC NAVIGATION SYSTEMS, RADIO This section sets forth requirements for radio navigation systems including LORAN,

OMEGA, SATNAV and TACAN. 424 ELECTRONIC NAVIGATION SYSTEMS, ACOUSTICAL This section sets forth requirements for depth indicators and acoustical navigation

systems.



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426 ELECTRICAL NAVIGATION SYSTEMS This section sets forth requirements for electrical navigation systems including dead

reckoning and gyrocompass systems. 427 INERTIAL NAVIGATION SYSTEMS This section sets forth requirements for inertial navigation systems including

alignment distribution systems and inertial system. 428 NAVIGATION CONTROL MONITORING This section sets forth requirements for navigation control monitoring and support

systems including chronometer transfer switches and central navigation computer. 430 INTERIOR COMMUNICATIONS This section sets forth general requirements for interior communication systems, the

detailed requirements of which are contained in other sections of the specification. 431 SWITCHBOARDS FOR INTERIOR COMMUNICATION SYSTEMS This section sets forth requirements for the selection and installation of switchboards

for energizing and controlling interior communication systems. The requirements of this section supplement those of section 430.

432 TELEPHONE SYSTEMS This section sets forth the requirements for the selection and installation of dial

phones and switchboards, sound powered phones, telephone amplifiers and telephone systems.

433 ANNOUNCING SYSTEMS This section sets for the requirements for announcing systems, intercom systems

and public address systems. 434 ENTERTAINMENT AND TRAINING SYSTEMS This section sets forth the requirements for motion picture equipment, radio and

television receivers, audio equipment, signal distribution equipment, tape recorders and television equipment.

435 VOICE TUBES AND MESSAGE PASSING SYSTEMS This section sets forth the requirements for voice tubes, passing tubes, pneumatic

tubes and couplings. 436 ALARM, SAFETY, AND WARNING SYSTEMS This section sets forth requirements for alarm panels, alarm switchboards, alarm

system, sensors and systems that give notice of equipment derangement or hazardous conditions.

437 INDICATING, ORDER, AND METERING SYSTEMS This section sets forth the requirements for indicating systems (including cavitation

and level indicating), order systems and metering systems including temperature indicating circuits, transmitters, valve control circuits, ship control circuits, and counters.

438 CONSOLIDATED CONTROL AND DISPLAY SYSTEMS This section sets forth requirements for integrated control systems including

combined instrument panels and portable ship controls. 439 RECORDING AND TELEVISION SYSTEMS This section sets forth requirements for closed circuit television systems, recording

systems, and remote recording and playback devices. 440 EXTERIOR COMMUNICATIONS This section sets forth requirements for exterior communication equipment including

audio frequency amplifiers, jack boxes, multicouplers, receivers, speakers, switchboards, telephones, transceivers, transmitters and tuners.

441 RADIO SYSTEMS This section sets forth requirements for radio systems including time and frequency

standards, radio set controls, central time and frequency, message processing systems, quality processing systems and satellite communication systems.

442 UNDERWATER SYSTEMS This section sets forth requirements for underwater communication equipment and

beacon equipment.



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443 VISUAL AND AUDIBLE COMMUNICATION SYSTEMS This section sets forth the requirements for visual infrared and audible systems used

for general communications and tactical signaling. 444 TELEMETRY SYSTEMS This section sets forth requirements for electronic systems for performing non-

combatant telemetry tasks. 445 TELETYPE AND FACSIMILE SYSTEMS This section sets forth requirements for teletype transmitting and receiving equipment

and facsimile systems. 446 SECURITY EQUIPMENT SYSTEMS This section sets forth requirements for equipment used for telecommunication

security. 450 SURVEILLANCE SYSTEMS, SURFACE AND AIR This section sets forth general requirements for surface and air radar. Sections 451

thru 459 address requirements for radar by specific function. 451 SURFACE SURVEILLANCE RADAR SYSTEMS This section sets forth requirements for surface search radar systems. 452 AIR SEARCH RADAR (2D) This section sets forth requirements for air search (2D) radar systems. 453 AIR SEARCH RADAR (3D) This section sets forth requirements for air search (3D) radar systems. 454 AIRCRAFT CONTROL APPROACH RADAR This section sets forth requirements for aircraft control approach radar. 455 IDENTIFICATION SYSTEMS (IFF) This section sets forth requirements for identification systems. 456 MULTIPLE MODE/FUNCTION RADAR This section sets forth requirements for multiple mode/function radar. 460 SURVEILLANCE SYSTEMS (UNDERWATER) This section sets forth general requirements for underwater surveillance systems.

Sections 461 thru 469 address requirements for underwater surveillance systems by specific function.

461 ACTIVE SONAR This section sets forth requirements for active sonar systems. 462 PASSIVE SONAR This section sets forth requirements for passive sonar systems. 465 BATHYTHERMOGRAPH The section sets forth requirements for temperature recording systems. 466 MULTI-PURPOSE SHIP EQUIPMENT SYSTEMS This section sets forth requirements for all systems and equipment relating to the

shipboard utilization of multi-purpose surveillance systems. 470 COUNTERMEASURE SYSTEMS This section sets forth general requirements for countermeasure systems. 471 ACTIVE ECM (INCL COMBINATION ACTIVE/PASSIVE) This section sets forth requirements for active ECM including complete radio, radar

and sonar ECM systems, including combination active/passive systems. 472 PASSIVE ECM This section sets forth requirements for passive ECM including passive radios, radar

and sonar ECM systems. 473 UNDERWATER COUNTERMEASURES This section sets forth requirements for underwater countermeasures including

torpedo decoys. 474 DECOY SYSTEMS This section sets forth requirements for decoy systems other than torpedo decoys. 475 DEGAUSSING SYSTEMS This section sets forth requirements for degaussing systems. 476 MINE COUNTERMEASURE SYSTEMS



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This section sets forth requirements for mine countermeasure systems including, acoustic minesweeping systems, magnetic minesweeping systems, mechanical minesweeping systems, mine countermeasures gear handling equipment, minefield navigation systems and minehunting systems.

480 FIRE CONTROL SYSTEMS This section sets forth requirements for performance, equipment and installation

requirements for electrical fire control systems and related signal and indicating systems.

481 GUN FIRE CONTROL SYSTEMS This section sets forth requirements for gun fire control systems not integral or

attached to the weapons. 482 MISSILE FIRE CONTROL SYSTEMS This section sets forth requirements for missile fire control systems not integral or

attached to the launchers. 483 UNDERWATER FIRE CONTROL SYSTEMS This section sets forth requirements for underwater fire control systems not integral

or attached to the launchers. 484 INTEGRATED FIRE CONTROL SYSTEMS This section sets forth requirements for integrated gun, missile and underwater fire

control systems not integral or attached to the weapons. 489 WEAPON SYSTEMS SWITCHBOARDS This section sets forth requirements for all fire control switchboards. 490 SPECIAL PURPOSE SYSTEMS This section sets forth general requirements for all command and surveillance

special purpose systems. 491 ELECTRONIC TEST, CHECKOUT, AND MONITORING EQUIPMENT This section sets forth requirements for all onboard non-dedicated electronic test,

checkout and monitoring equipment for servicing and repairing command and surveillance systems.

492 FLIGHT CONTROL AND INSTRUMENT LANDING SYSTEMS This section sets forth requirements for flight control and instrument landing systems. 493 AUTOMATED DATA PROCESSING SYSTEMS (NON-COMBAT) This section sets forth requirements for non-combat automated data processing

systems. 494 METEOROLOGICAL SYSTEMS This section sets forth requirements for meteorological systems. 495 SPECIAL PURPOSE INTELLIGENCE SYSTEMS This section sets forth requirements for special purpose intelligence systems. 499 COMMAND AND SURV. REPAIR PARTS AND SPECIAL TOOLS This section sets forth requirements for all repair parts, replacement items, special

tools and handling gear carried onboard and used to service and repair the command and surveillance system.



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500 AUXILIARY SYSTEMS, GENERAL 501 GENERAL ARRANGEMENT-AUXILIARY SYSTEMS DRAWINGS 502 AUXILIARY MACHINERY This section sets forth requirements for auxiliary gas turbines and auxiliary diesel

engines. 503 PUMPS This section sets forth requirements for the selection, application and installation of

pumps. 504 INSTRUMENTS AND INSTRUMENT BOARDS This section sets forth the requirements for instrumentation and instrument boards

including mechanical, electrical and other means of sensing, transmitting and indication.

505 GENERAL PIPING REQUIREMENTS This section sets forth general requirements for the design, construction, fabrication,

arrangement, installation, testing and cleaning of shipboard piping systems and piping components.

506 OVERFLOWS, AIR ESCAPES, AND SOUNDING TUBES This section sets forth the requirements for overflows, air escapes and sounding

tubes. 507 MACHINERY AND PIPING DESIGNATION AND MARKING This section sets forth requirements for machinery and piping designating and

marking. 508 THERMAL INSULATION FOR PIPING AND MACHINERY This section sets forth requirements for thermal insulation of machinery, equipment

and piping. 509 INSULATION FOR VENT AND A/C DUCTS This section sets forth requirements for thermal and acoustic insulation of vent and

air conditioning ducts. 510 CLIMATE CONTROL This section sets forth general requirements for the climate control systems. The

details for specific systems are covered in the following sections of the specification. 511 COMPARTMENT HEATING SYSTEM This section sets forth requirements for compartment heating systems, including

convection heaters, duct heaters, regulators, radiant heaters, unit heaters and thermostats.

512 VENTILATION SYSTEM This section sets forth requirements for design, selection, arrangement and

installation of supply fans, exhaust fans and duct work not including the machinery spaces.

513 MACHINERY SPACE VENTILATION SYSTEM This section sets forth requirements for design, selection, arrangement and

installation of supply fans, exhaust fans and duct work for the machinery spaces. 514 AIR CONDITIONING SYSTEM This section sets forth the requirements for design, selection, arrangement,

installation and cleaning of equipment and refrigerant piping for the air conditioning plant.

516 REFRIGERATION SYSTEM This section sets forth requirements for the design, selection, arrangement,

installation and cleaning of equipment and refrigerant piping for refrigerating plants. 517 AUXILIARY BOILERS AND OTHER HEAT SOURCES This section sets forth requirements for the design, selection, arrangement and

installation of auxiliary boilers and other heat sources. 520 SEA WATER SYSTEMS



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This section sets forth requirements for firemain systems, firefighting systems employing seawater only, washdown counter-measure systems and flushing systems.

521 FIREMAIN AND FLUSHING (SEA WATER) SYSTEM This section contains general requirements for firemain systems, firefighting systems,

employing seawater only, washdown counter-measure systems and flushing systems.

522 SPRINKLER SYSTEM This section sets forth requirements for fire extinguishing sea water sprinkling

systems throughout the ship, including wet or dry type; automatic or manual controlled including vital space perimeter and living space sprinkler systems and incinerator sprinkling systems.

523 WASHDOWN SYSTEM This section sets forth requirements for countermeasure wash down systems. 524 AUXILIARY SEA WATER SYSTEM This section sets forth requirements for seawater cooling of auxiliary machinery

systems including condensers, heat exchangers, coolers, thrust and line shaft stern tube bearings and the cooling of air ejectors and gland exhausts.

526 SCUPPERS AND DECK DRAINS This section sets forth the general requirements for gravity drainage systems serving

interior space deck drains and weather deck drains. 527 FIREMAIN ACTUATED SERVICES - OTHER This section sets forth requirements for countermeasure piping systems, firemain

actuated services, fog systems and spray nozzles. 528 PLUMBING DRAINAGE This section sets forth the general requirements for gravity drainage systems serving

plumbing fixtures and air conditioning condensate drains. 529 DRAINAGE AND BALLASTING SYSTEM This section sets forth the requirements for design, arrangement and installation of

drainage and ballasting systems. Gravity drainage in covered in section 528. 530 FRESH WATER SYSTEMS This section sets forth general requirements for all freshwater service systems

including tank filling, stowage, transfer and service arrangements. Requirements for specific freshwater systems are covered in the following sections.

531 DISTILLING PLANT This section sets forth general requirements for the design, construction, fabrication,

arrangement, installation, testing and cleaning of distilling systems. 532 COOLING WATER This section sets forth requirements for freshwater cooling systems that do not utilize

a seawater/freshwater heat exchanger. 533 POTABLE WATER This section sets forth requirements for the design, construction, fabrication and

arrangement of hot and cold potable water systems, helicopter washdown systems, and the disinfection system.

534 MACHINERY AND PIPING SYSTEMS DRAINAGE This section sets forth the requirements for drainage systems for equipment and

piping stems where water or oil and water/oil mixtures can accumulate. 536 AUXILIARY FRESH WATER COOLING

This section sets forth requirements for the design, installation, inspection, repair, removal, installation and testing of cooling equipment utilizing sea water/fresh water heat exchanger.

540 FUELS AND LUBRICANTS, HANDLING AND STORAGE This section sets forth general requirements for the design, arrangement and

construction of systems that store and transfer petroleum products onboard the ship. Requirements for systems handling specific petroleum products are covered in the



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following sections. 541 SHIP FUEL AND FUEL COMPENSATING SYSTEM This section sets forth requirements for the design, construction, arrangement and

cleaning of tanks, filling and transfer piping, pumps and equipment for the propulsion fuel system.

542 AVIATION AND GENERAL PURPOSE FUELS This section sets forth requirements for the design, construction, arrangement and

cleaning of tanks, filling and transfer piping, pumps and equipment for the aviation and general-purpose fuel system.

543 AVIATION AND GENERAL PURPOSE LUBRICATING OIL This section sets forth requirements for the design, construction, arrangement and

cleaning of tanks, filling and transfer piping, pumps and equipment for the aviation and general purpose lubricating oil system.

544 LIQUID CARGO This section sets forth requirements for the design, construction, arrangement and

cleaning of tanks, filling and transfer piping, pumps and equipment for the liquid cargo system.

545 TANK HEATING This section sets forth requirements for the design, construction, and arrangement of

the tank heating system. 546 AUXILIARY LUBRICATION SYSTEMS This section sets forth requirements for the design, construction, arrangement and

cleaning of tanks, filling and transfer piping, pumps and equipment for the auxiliary lubrication system.

549 SPECIAL FUEL AND LUBRICANTS, HANDLING AND STOWAGE This section sets forth requirements for the design, construction and arrangement of

special fuel and lubricant handling and stowage systems. 550 AIR, GAS, AND MISCELLANEOUS FLUID SYSTEMS This section sets forth the general requirements for the design, construction,

arrangement of air gas and miscellaneous systems. Requirements for specific systems are addressed in the following section of the specification.

551 COMPRESSED AIR SYSTEMS This section sets forth the requirements for the design, arrangement and construction

of the compressed air systems. 552 COMPRESSED GASES This section sets forth the requirements for the design, arrangement, installation and

testing of oxygen systems, hydrogen systems and inert gas systems. 555 FIRE EXTINGUISHING SYSTEMS This section sets forth the requirements for portable, hose reel and dry chemical fire

extinguishers and fixed flooding systems. Fire extinguishing systems employing seawater are covered in section 521.

556 HYDRAULIC FLUID SYSTEM This section sets forth requirements for the design, arrangement, construction and

cleaning of the hydraulic fluid systems. 558 SPECIAL PIPING SYSTEMS This section sets forth requirements for the design, arrangement and construction of

the special piping systems. 560 SHIP CONTROL SYSTEMS This section sets forth requirements for the systems that control the direction and

attitude of the ship. 562 RUDDER This section sets forth requirements for the design and construction of the rudder(s). 565 TRIM AND HEEL SYSTEMS (SURFACE SHIPS) This section sets forth requirements for active fin systems, active tank roll

stabilization systems, heel systems, passive stabilization systems, stabilizing fins and trim systems.



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567 STRUT AND FOIL SYSTEMS This section sets forth requirements for the design and construction of hydrofoil

systems including foils, struts, retraction members, foundation attachment fittings, flaps and bearings.

568 MANEUVERING SYSTEMS This section sets forth requirements for the design and construction of maneuvering

systems including steering control thrusters, air cushion vehicle maneuvering systems, thruster prime movers and thruster system associated components.

570 REPLENISHMENT SYSTEMS This section sets forth general requirements for the design and construction of

replenishment-at-sea systems, stores handling systems, cargo handling systems and vertical replenishment systems.

571 REPLENISHMENT-AT-SEA SYSTEMS This section sets forth requirements for replenishment-at-sea systems and

equipment used for the transfer of fuel, water, weapons, cargo, stores, provisions, mail and personnel between ships underway.

572 SHIP STORES AND EQUIPMENT HANDLING SYSTEMS This section sets forth requirements for handling systems and equipment used for

the movement of stores and provisions carried onboard for the ship’s own use. These systems and equipment are used for strike down of stores and provisions from receiving areas to stowage in the storerooms and for strike up from the storerooms to locations convenient for their use.

573 CARGO HANDLING SYSTEMS This section sets forth requirements for handling systems and equipment used for

movement of commodities carried onboard as cargo, other than weapons and bulk liquids. These systems are used between the ship and pier, barges, and lighters; between loading and unloading areas and stowage spaces; between replenishment stations and stowage spaces and within stowage spaces.

574 VERTICAL REPLENISHMENT SYSTEMS This section sets forth requirements for vertical replenishment systems and

equipment used for the transfer of stores, provisions, mail and personnel between ships underway and aircraft.

580 MECHANICAL HANDLING SYSTEMS This section sets forth general requirements for the design and construction of

mechanical handling systems. Requirements for specific mechanical handling system are addressed in the following sections.

581 ANCHOR HANDLING AND STOWAGE SYSTEMS This section sets forth the requirements for the design and construction the anchor,

and the anchor handling and stowage system; this includes the anchor, the anchor chain, hawspipe, anchor windlass, chain locker and chain stoppers.

582 MOORING AND TOWING SYSTEMS This section sets forth the requirements for the mooring and towing systems. The

mooring system includes mooring winches, mooring capstans, mooring lines, bitts, cleats and chocks. Towing systems include towing bits, capstans and towing lines.

583 BOATS, BOAT HANDLING AND STOWAGE SYSTEMS This section sets forth the requirements for the boats and life rafts, requirements for

the design and arrangement of boat handling systems and stowage of boats and life rafts.

584 DOORS, HATCHES, GATES AND RAMPS, MECHANICALLY OPERATED This section sets froth the requirements for the design and construction of

mechanically operated doors and hatches. 586 AIRCRAFT RECOVERY SUPPORT SYSTEMS This section sets forth the requirements for the design and construction of aircraft

recovery support systems including the flight deck, haul down and capture systems, 588 AIRCRAFT HA NDLING, SERVICING AND STOWAGE This section sets forth the requirements for the design and construction of the aircraft



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handling, servicing and stowage systems. This includes requirements for the aircraft hangar, hangar door, tie down fittings, traversing systems, and stowage equipment.

590 SPECIAL PURPOSE SYSTEMS This section sets forth the general requirements for the design and construction of

special purpose systems. Requirements for specific systems are included in the following specification sections.

591 SCIENTIFIC AND OCEAN ENGINEERING SYSTEMS This section sets forth requirements for scientific and ocean engineering systems

including ocean work systems, jettisoning systems, manipulators and submersible vehicle mechanical systems.

592 SWIMMER AND DIVER SUPPORT AND PROTECTION SYSTEMS This section sets forth the requirements for diver and swimmer cages, diver

equipment stowage, diver tools, diver support and protection systems and swimmer support and protection systems.

593 ENVIRONMENTAL POLLUTION CONTROL SYSTEMS This section sets forth the requirements for air pollution abatement systems, oil

pollution abatement systems, sewage treatment and disposal systems, industrial and chemical waste disposal systems, waste disposal systems, and waste water treatment and disposal systems.

595 TOWING, LAUNCHING AND HANDLING FOR UNDERWATER SYS. This section sets forth requirements for the design and construction of launching

systems for bathythemographs, communication buoys, signals and counter measures.

598 AUXILIARY SYSTEMS OPERATING FLUIDS This section sets forth the requirements for fluids contained in closed, open and free

flooding auxiliary systems. 599 AUXILIARY SYSTEMS REPAIR PARTS AND TOOLS This section sets forth requirements for all repair parts, replacement items, special

tools and handling gear carried onboard and used to service and repair auxiliary systems.



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600 OUTFIT AND FURNISHINGS, GENERAL 601 GENERAL ARRANGEMENT - OUTFIT AND FURN. DRAWINGS 602 HULL DESIGNATING AND MARKING This section sets forth requirements for the marking and designating of the hull;

including builders name plate, interior markings, label plates and ships name board. 603 DRAFT MARKS This section sets forth the requirements for navigational and calculative draft marks. 604 LOCKS, KEYS, AND TAGS This section sets forth the requirements for locks keys and tags. 605 RODENT AND VERMIN PROOFING This section sets forth requirements for rat proofing the ship. 610 SHIP FITTINGS This section sets forth general requirements for ship fittings including hull fittings,

rails, stanchions, lifelines, rigging and canvas. 611 HULL FITTINGS This section sets forth requirements for hull fittings including davits, deck chafing

plates, deck fittings, fenders, guards, jackstaffs, padeyes for lifting and lashing, safety tracks, shell brackets and spars.

612 RAILS, STANCHIONS, AND LIFELINES This section sets for the requirements for rails, stanchions, and lifelines including

awning braces, hand rails, pipe railings, fittings and safety nets. 613 RIGGING AND CANVAS This section sets forth requirements for rigging and canvas including awnings,

canopies, covers, curtains, flag hoists, halyards, hoods, running and standing rigging, shrouds and stays, tarpaulins and weather cloths.

620 HULL COMPARTMENTATION This section sets forth general requirements for all non-structural compartmentation

in the hull, including non-structural bulkheads, floor plates and gratings, ladders, non-structural closures, airports, fixed portlights and windows.

621 NON-STRUCTURAL BULKHEADS This section sets forth requirements for non-structural bulkheads including joiner

bulkheads, coamings, expanded metal bulkheads, fastenings, frames, sanitary partitions, shower partitions and sills.

622 FLOOR PLATES AND GRATINGS This section sets forth requirements for floor plates and gratings including coverings,

false floors, fastenings, fittings, frames, handrails and supports. 623 LADDERS This section sets forth requirements for ladders including abandon ship ladders,

accommodation ladders, Jacobs ladders, inclined and vertical ladders and pilot ladders.

624 NON-STRUCTURAL CLOSURES This section sets forth requirements for non-structural closures including coamings,

joiner doors, non-structural doors, expanded metal doors, and service windows. 625 AIRPORTS, FIXED PORTLIGHTS, AND WINDOWS This section sets forth requirements for airports, fixed lights and windows including

covers, peepholes, screens, windshields and wipers. 630 PRESERVATIVES AND COVERINGS This section sets forth general requirements for preservatives and coverings

including painting, zinc and metallic coatings, cathodic protection, deck coverings, hull insulation, hull damping, sheathing and refrigerated spaces.

631 PAINTING This section sets forth requirements for cleaning, preparation and painting of interior

and exterior areas of the hull and superstructure.



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632 ZINC AND METALLIC COATINGS This section sets forth requirements for zinc coatings, galvanizing, flame sprayed

aluminum, metallic cladding and metallic special purpose coatings. 633 CATHODIC PROTECTION This section sets forth requirements for cathodic protection including controllers,

anodes and gland assemblies. 634 DECK COVERING This section sets forth requirements for deck coverings including concrete, ceramic

and non-skid tile, composition and metal deck coverings, deck treads and mats, carpeting, electric grade mats and rubber mats.

635 HULL INSULATION This section sets forth requirements for acoustical and thermal hull insulation and

soundproofing. 636 HULL DAMPING This section sets forth requirements for hull damping and vibration damping tile and

sandwich treatments. 637 SHEATHING This section sets forth requirements for sheathing including acoustical sheathing,

coverings of built in furnishings, decorative sheathing, medical and dental sheathing, protective sheathing and sanitary sheathing.

638 REFRIGERATED SPACES This section sets forth requirements for refrigerated spaces including battens, doors

gratings, insulation and sheathing. 640 LIVING SPACES This section sets forth requirements for berthing spaces, leisure and community

spaces and sanitary spaces for officers, non-commissioned officers, and enlisted personnel. This section also sets forth requirements for furnishing including: beds, bedding, berth lights, berths, bookcases, fans, buffets, bureaus, cabinets, chains, chaplains equipment, chiffoniers, chronometers, clocks, clothes lockers, curtain rods, curtains, desks, furnishings and outfitting, linen lockers, linens, lockers, mess gear dispensers, mess tables, mirrors, portable lamps, racks, servers, serving tables, shelves, tableware, toilet cases, transoms, and wardrobes.

641 OFFICER BERTHING AND MESSING SPACES This section sets forth requirements for all officer and passenger berthing and

messing spaces. 642 NONCOMMISSIONED OFFICER BERTHING AND MESSING SPACES This section sets forth requirements for all noncommissioned officer berthing and

messing spaces. 643 ENLISTED PERSONNEL BERTHING AND MESSING SPACES This section sets forth requirements for all enlisted personnel berthing and messing

spaces. 644 SANITARY SPACES AND FIXTURES This section sets forth requirements for arrangement of sanitary spaces for ships

force and sets forth requirements for furnishings and fixtures. 645 LEISURE AND COMMUNITY SPACES This section sets forth requirements for religious, library, physical fitness, lounge and

special activity spaces. 650 SERVICE SPACES This section sets forth general requirements for food service spaces, medical and

dental spaces, utility spaces, laundry spaces, and trash disposal spaces. 651 COMMISSARY SPACES This section sets forth requirements for the arrangement, functionality and furnishing

of food service spaces. 652 MEDICAL SPACES This section sets forth requirements for the arrangement, functionality and furnishing

of medical spaces.



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653 DENTAL SPACES This section sets forth requirements for the arrangement, functionality and furnishing

of dental spaces. 654 UTILITY SPACES This section sets forth requirements for the arrangement, functionality and furnishing

of utility spaces. 655 LAUNDRY SPACES This section sets forth requirements for the arrangement, functionality and furnishing

of laundry spaces. 656 TRASH DISPOSAL SPACES This section sets forth requirements for the arrangement, functionality and furnishing

of trash disposal spaces. 660 WORKING SPACES This section sets forth general requirements for outfitting working spaces, including:

offices, machinery control centers, electronics control centers, damage control centers, workshops, labs and test areas.

661 OFFICES This section sets forth requirements for furnishing offices. 662 MACHINERY CONTROL CENTERS FURNISHINGS This section sets forth requirements for furnishing machinery control centers. 663 ELECTRONICS CONTROL CENTERS FURNISHINGS This section sets forth requirements for furnishing electronics control centers. 664 DAMAGE CONTROL STATIONS This section sets forth requirements for outfitting and equipping damage control

stations. 665 WORKSHOPS, LABS, TEST AREAS (INCL PORTABLE TOOLS, EQUIP) This section sets forth requirements for the arrangement, outfitting and equipping of

workshops, labs and test areas. 670 STOWAGE SPACES This section sets forth general requirements for all onboard stowage except

weapons, ammunition and liquids in tanks. 671 LOCKERS AND SPECIAL STOWAGE This section sets forth requirements for abandon ship lockers, chemical defense

lockers, cleaning gear lockers, deck gear lockers, foul weather gear lockers and fire fighting clothing lockers.

672 STOREROOMS AND ISSUE ROOMS This section sets forth requirements for the arrangement and furnishing of

storerooms and issue rooms including stowage aids and stowage fittings and securing fittings.

673 CARGO STOWAGE This section sets forth requirements for the arrangement and furnishing of cargo

storerooms including stowage aids and stowage fittings and securing fittings. 690 SPECIAL PURPOSE SYSTEMS This section sets forth requirements for special purpose systems. 698 OUTFIT AND FURNISHINGS OPERATING FLUIDS This section sets forth requirements for fluids contained in components, units and

systems of outfit and furnishing to make them operable. 699 OUTFIT AND FURNISH. REPAIR PARTS AND SPECIAL TOOLS This section sets forth requirements for all repair parts, replacement items and

special tools carried onboard and used to service and repair furnishing and outfit items.



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700 ARMAMENT, GENERAL 701 GENERAL ARRANGEMENT - WEAPONRY SYSTEMS 702 ARMAMENT INSTALLATIONS This section sets forth requirements for installation of armament and associated

equipment. 703 WEAPONS HANDLING AND STOWAGE, GENERAL This section sets forth general requirements for the design and installation of

weapons handling and stowage systems and equipment. 710 GUNS AND AMMUNITION This section sets forth general requirements for guns and ammunition. 711 GUNS This section sets forth the requirements for the design and installation of the ship’s

guns. 712 AMMUNITION HANDLING This section sets forth requirements for the handling of ship’s gun ammunition. 713 AMMUNITION STOWAGE This section sets forth requirements for the stowage of ship’s gun ammunition. 720 MISSILES AND ROCKETS This section sets forth general requirements for missiles and rockets. 721 LAUNCHING DEVICES (MISSILES AND ROCKETS) This section sets forth requirements for devices used for launching missiles and

rockets. 722 MISSILE, ROCKET, AND GUIDANCE CAPSULE HANDLING SYS. This section sets for requirements for handling missiles, rockets, boosters, decoys

and their components between the receiving stations, the launching systems, magazines and within the magazines as applicable.

723 MISSILE AND ROCKET STOWAGE This section sets forth requirements for missile, rocket and decoy stowage. 730 MINES This section sets forth the general requirements for the design and installation of the

ship’s mine handling, launching and stowage systems. 731 MINE LAUNCHING DEVICES This section sets forth requirements for mine launching devices. 732 MINE HANDLING This section sets forth requirements for mine handling devices. 733 MINE STOWAGE This section sets forth requirements for mine stowage. 740 DEPTH CHARGES This section sets forth the general requirements for the design and installation of the

ship’s depth charge handling, launching and stowage systems. 741 DEPTH CHARGE LAUNCHING DEVICES

This section sets forth requirements for depth charge launching devices.

742 DEPTH CHARGE HANDLING This section sets forth requirements for depth charge handling devices. 743 DEPTH CHARGE STOWAGE This section sets forth requirements for depth charge stowage. 760 SMALL ARMS AND PYROTECHNICS This section sets forth general requirements for small arms and pyrotechnics. 761 SMALL ARMS AND PYROTECHNIC LAUNCHING DEVICES This section sets forth requirements for handguns, rifles, saluting guns, signal and

beacon projections and pyrotechnic launching devices. 762 SMALL ARMS AND PYROTECHNIC HANDLING



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This section sets forth requirements for handling of small arms ammunition, miscellaneous ordnance and pyrotechnics.

763 SMALL ARMS AND PYROTECHNIC STOWAGE This section sets forth requirements for stowage of small arms ammunition,

miscellaneous ordnance and pyrotechnics. 799 ARMAMENT REPAIR PARTS AND SPECIAL TOOLS This section sets forth requirements for all repair parts, replacement items and

special tools carried onboard and used to service and repair armament.



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The following sections of the work breakdown structure are provided primarily for

cost estimating and progress reporting. However these sections also provide an outline for developing contract requirements for engineering, analyses, drawings, and reports that may be required.

800 INTEGRATION/ENGINEERING (SHIPBUILDER RESPONSE) 801 SHIPBUILDERS INFORMATION DRAWINGS 802 CONTRACT DRAWINGS 803 STANDARD DRAWINGS 804 TYPE DRAWINGS 806 STUDY DRAWINGS 807 INSTALLATION CONTROL DRAWINGS 808 INTERFACE CONTROL DRAWINGS 810 PRODUCTION ENGINEERING 811 CONFIGURATION MANAGEMENT 812 CHANGE PROPOSALS, SCOPING AND SHIP CHECKING 813 PLANNING AND PRODUCTION CONTROL 830 DESIGN SUPPORT 831 CONSTRUCTION DRAWINGS 832 SPECIFICATIONS 833 MASS PROPERTIES ENGINEERING 834 COMPUTER PROGRAMS 835 ENGINEERING CALCULATIONS 836 MODELS AND MOCKUPS 837 PHOTOGRAPHS 838 DESIGN/ENGINEERING LIAISON 839 LOFTING 840 QUALITY ASSURANCE 841 TESTS AND INSPECTION, CRITERIA, AND PROCEDURES 842 TRIALS AGENDA PREPARATION, DATA COLLECTION AND ANAL. 843 INCLINING EXPERIMENT AND TRIM DIVE 844 COMBAT SYSTEMS CHECKOUT CRITERIA AND PROCEDURES 845 CERTIFICATION STANDARDS 850 INTEGRATED LOGISTIC SUPPORT ENGINEERING 851 MAINTENANCE 852 SUPPORT AND TEST EQUIPMENT 853 SUPPLY SUPPORT 854 TRANSPORTATION 855 ENGINEERING DRAWINGS AND SPECIFICATIONS 856 TECHNICAL MANUALS AND OTHER DATA 857 FACILITIES 858 PERSONNEL AND TRAINING 859 TRAINING EQUIPMENT 880 AUTHORIZED REPAIR PLANNING 881 FUNDS 890 SPECIAL PURPOSE ITEMS 891 SAFETY 892 HUMAN FACTORS 893 STANDARDIZATION 894 VALUE ENGINEERING 895 RELIABILITY AND MAINTAINABILITY 896 DATA MANAGEMENT 897 PROJECT MANAGEMENT



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900 SHIP ASSEMBLY AND SUPPORT SERVICES 901 901 THRU 979 RESERVED FOR IDENT. OF ASSEMBLIES 980 CONTRACTUAL AND PRODUCTION SUPPORT SERVICE 981 INSURANCE 982 TRIALS 983 DELIVERY 985 FIRE AND FLOODING PROTECTION 986 TESTS AND INSPECTION 987 WEIGHING AND RECORDING 988 CONTRACT DATA REQUIREMENTS (ADMINISTRATION) 989 FITTING-OUT 990 CONSTRUCTION SUPPORT 991 STAGING, SCAFFOLDING, AND CRIBBING 992 TEMPORARY UTILITIES AND SERVICES 993 MATERIAL HANDLING AND REMOVAL 994 CLEANING SERVICES 995 MOLDS AND TEMPLATES, JIGS, FIXTURES, AND SPEC. TOOLS 996 LAUNCHING 997 DRY DOCKING



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The following sections of the work breakdown structure are provided primarily for

weight estimating purposes. F00 LOADS (FULL-LOAD CONDITION) F10 SHIPS FORCE, AMPHIB. FORCE, TROOPS AND PASSENGERS F11 SHIPS OFFICERS F12 SHIPS NONCOMMISSIONED OFFICERS F13 SHIPS ENLISTED MEN F14 MARINES F15 TROOPS F16 AIR WING PERSONNEL F19 OTHER PERSONNEL F20 MISSION-RELATED EXPENDABLES AND SYSTEMS F21 SHIP AMMUNITION (FOR USE BY SHIP ON WHICH STOWED) F22 ORDNANCE DELIVERY SYSTEMS AMMUNITION F23 ORDNANCE DELIVERY SYSTEMS F24 ORDNANCE REPAIR PARTS (SHIP AMMO) F25 ORDNANCE REPAIR PARTS (ORDNANCE DELIVERY SYS. AMMO)

F26 ORDNANCE DELIVERY SYSTEMS SUPPORT EQUIPMENT F29 SPECIAL MISSION-RELATED SYSTEMS AND EXPENDABLES F30 STORES F31 PROVISIONS AND PERSONNEL STORES F32 GENERAL STORES F33 MARINES STORES (FOR SHIP'S COMPLEMENT) F39 SPECIAL STORES F40 FUELS AND LUBRICANTS F41 DIESEL FUEL F42 JP-5 F43 GASOLINE F44 DISTILLATE FUEL F45 NAVY STANDARD FUEL OIL (NSFO) F46 LUBRICATING OIL F49 SPECIAL FUELS AND LUBRICANTS F50 LIQUIDS AND GASES (NON FUEL TYPE) F51 SEA WATER F52 FRESH WATER F53 RESERVE FEED WATER F54 HYDRAULIC FLUID F55 SANITARY TANK LIQUID F56 GAS (NON FUEL TYPE) F59 MISCELLANEOUS LIQUIDS (NON FUEL TYPE) F60 CARGO F61 CARGO, ORDNANCE AND ORDNANCE DELIVERY SYSTEMS F62 CARGO, STORES F63 CARGO, FUELS AND LUBRICANTS F64 CARGO, LIQUIDS (NON FUEL TYPE) F65 CARGO, CRYOGENIC AND LIQUEFIED GAS F66 CARGO, AMPHIBIOUS ASSAULT SYSTEMS F67 CARGO, GASES F69 CARGO, MISCELLANEOUS



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M00 MARGINS M10 CONTRACTOR CONTROLLED MARGINS M11 DESIGN AND BUILDING MARGIN M12 BUILDING MARGIN M20 GOVERNMENT CONTROLLED MARGIN M21 PRELIMINARY DESIGN MARGIN M22 CONTRACT DESIGN MARGIN M23 CONTRACT MODIFICATION MARGIN

M24 GEM MARGIN M25 FUTURE GROWTH MARGIN M26 SERVICE LIFE MARGIN



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APPENDIX 9.8

HULL FORM



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ADVANCED MONOHULLS by

Gregory Grigoropoulos, Assoc. Professor NTUA 1. Introduction

Increased speed was a common feature of many passenger ships and ferries built in the last decade. This is a market where fast monohulls dominate, although fast catamarans possess a remarkable portion, especially at the higher speed range. However, as it is shown in Fig. 1, from Levander, (2001), enriched by Grigoropoulos and Loukakis (2002), speed is relative, and this means that a vessel becomes faster not only by increasing the speed, but also by reducing its length.

This is a most interesting case for naval ships, where modern efficient weapons can be accommodated in smaller platforms. According to this Figure and other pertinent information one can define (today!) a “fast monohull” ship in the pre-planing regime as one with LWL between 40m and 150m, running at speeds between 25 and 45 knots.

Figure 1: Speed is relative. Fast designs of the 90s

The case for advanced monohulls will be discussed in this chapter. Some novel systematic series of hull forms for this type of ships have been recently (since 1995) presented in parallel with the development of alternative advanced hull forms. The series, which have advantageous resistance performance in the semi-displacement or pre-planing regime (Froude Number range = 0.40 – 0.90), are: • VWS D-Serie, Berlin (Kracht, 1996) • SKLAD series, Zagreb (Gamulin, 1996) • AMECRC systematic series (Bojovic, 1997) • NTUA series of double-chine, wide-transom hulls (Grigoropoulos & Loukakis, 1999)

The latter two of the series have also improved seakeeping characteristics. Anyway, the above series extend the scope of the older systematic series of fast monohulls, which are: • KTH/NSMB Series of round-bilge and hard-chine hulls, developed in SSPA Towing Tank

(Nodrstrom 1955, Clement 1964). • Series 62 single chine (Clement and Blount, 1963) • Series 63 (Beys, 1963)

0 50 100 150 200 250 3000

10

20

30

40

50

Length WL [m]

Spe

ed [

knot

s]

Fn=1.00Fast Cat

Fn=0.60

Fast MonoFn=0.35

Fn=0.25DisplacementType Ferries



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• Series 64 (Yeh, 1965) • Series 65 (Holling and Hubble, 1974) • NPL Series of round-bilge hulls (Bailey, 1976) • NRC Series of naval ships (Schmitke et al, 1979 and Murdey and Simoes Re, 1985). • Deep-V single chine based on Series 62 (Keuning and Gerritsma, 1982) • HSVA C' Series (Kracht and Grim, 1960) • NSMB Series of round-bilge,semi-displacement hullforms (Oossanen & Pieffers,1984) • VTT Series (Lahtiharju et al, 1991).

Furthermore, six methods are available to the designer of a fast monohull to estimate its resistance during the preliminary design phase. These readily applicable, semi-empirical methods, which are based on one or more sets of model tests, are: • Savitsky method for prismatic hulls, including Blount and Fox correction factor for pre-planing

regime (Savitsky, 1964, Blount and Fox, 1976) • Van Oortmerssen method (Van Oortmerssen, 1971) • Mercier and Savitsky method (Savitsky ?a? Brown, 1976) • Tang method (Ping-zhong et al, 1980) • Holtrop method (Holtrop, 1984) • Compton method (Compton, 1986)

It should be noted here that, the availability of modern and efficient hullforms is of vital importance for the designer who has to concentrate his effort to a specific hull form type to be improved during the final design spiral. On the other hand, only a few of the aforementioned methods are based on systematic experimental results.

Furthermore, some local modifications of the hull form, including the fitting of appendages, are applied on fast monohulls to improve the efficiency of their operation at high speed in calm water. These modifications and their effect on the behaviour of the vessel are presented and discussed in Section 3.

Finally, a major hull form modification in the conceptual design phase, aiming at improving both the calm and rough water performance of a vessel is described in Section 4. The Enlarged Ship Concept (ESC) introduced by Keuning and Pinkster (1995) is discussed from the resistance, seakeeping and manoeuvring (including broaching) point of view. 2. High-Speed Light-Displacement Monohulls

VWS D-Series

The series originates from a twin-screw round bilge hull form, and refers to relatively broad and short ships. Kracht (1992, 1996) reported on the resistance, wake and propulsion tests carried out with the 13 models of the series.

All models had a common length between perpendiculars LBP = 6.00 m. The body plan of the

parent model is shown in Fig. 2. Its form parameters are given in Table 1. To generate the series, CP coefficient, B/T ratio and C∇ were varied as it is shown in Table 2.



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Figure 2: Body plan of the parent model of D-Series

Table 1: Form Parameters of parent hull form of D-Series

Parameter Value Prismatic Coefficient CP = ∇/(AM LBP) 0.600 B/T ratio (amidships) 3.75 Slenderness coefficient 103C∇ = 103∇/LBP

3 3.00 Sectional Coefficient CX at maximum Section (Section 9) 0.8065 Longitudinal Centre of Buoyancy LCB/LBP (fwd of transom) 0.475

Note: AM represents the sectional area of the maximum section and ∇ the volume of displacement.

Table 2: Form Parameters varied to generate D-Series

CP 0.600 0.620 0.646 B/T 3.500 3.750 4.000 103C∇ 3.000 3.500 4.000

Tests have been carried out at three displacements and for speeds corresponding to Froude

Numbers Fn = 0.15 – 0.80. The effect of appendages (bossing, V-bracket and rudder) was investigated at the intermediate displacement. At the same displacement, wake and self-propulsion tests have been carried out. Finally, the effect of trim by bow and by stern has been investigated for the intermediate displacement of the last three models of the series.

The results presented are: model test raw data for the naked hull and the hull with appendage resistance, open water propeller characteristics, self propulsion and wake tests as well as residual resistance coefficients CR, running trim and dynamic CG rise, velocity field in the propeller disk, propulsive performance coefficients, wake fraction w, thrust deduction factor t and relative rotative efficiency ?R.



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SKLAD series

SCLAD series were a designer oriented series developed at the Bodarski Institute (Zagreb, Croatia) during the 70s and first published in 1996 (Gamulin). The body plan of the parent model of the series is shown in Fig. 3 and its characteristics are presented in Table 3. The series consists of 27 models with form parameters as shown in Table 4, which were tested for speeds corresponding to volumetric Froude Numbers Fn∇ = 1.0 – 3.0 and displacements in the range of the non-dimensional coefficient M = LWL/∇

1/3 = 4.50 to 8.50.

Figure 3: Body plan and bow and stern profiles of the parent model of SCLAD series

Table 3: Form Parameters of the parent hull form of SCLAN series

Parameter Value Length between perpendiculars LBP = 1.0129 LWL (m) 4.250 Prismatic Coefficient CP = ∇/(AM LBP) 0.715 Sectional Coefficient CX at maximum Section 0.621 LCB/LBP (positive forward of midship section) -0.09186 Half-angle of entrance iE 12.0o

The series is split in three groups depending on the CB values provided in Table 4. Each group of

the series has constant CP, CX, CWP (waterplane area coefficient) and position of LCB (-0.087 LBP, -0.09186 LBP and -0.091 LBP for CB = 0.35, 045 and 0.55, respectively). The models were derived form the parent and the basic forms for CB = 0.35 and 0.55, so that the model displacement was always constant (∇M = 0.230 m3), while LWL/BWL, BWL/T and CB were constant in each group. Furthermore, all models were tested at level keel.

Table 4: Form Parameters varied to generate SCLAD series

LWL/BWL 4.00 6.00 8.00 BWL/T 3.00 4.00 5.00 CB 0.350 0.450 0.550

The results are presented in the form of a grid of constant value curves for residual resistance

coefficients CR, running trim, dynamic rise of the centre of gravity (CG) and running wetted surface, on CB, LWL/BWL axes. Graphs are provided for each BWL/T and testing speed, corresponding to Fn∇ = 1.00-2.50 (step 0.25) and 3.00 The last two results were non-dimensionalized by ∇1/3 and ∇2/3, respectively, while CR was derived on the basis of the running wetted surface. Since 22 ships have been constructed using the hull form of the series, a reliable relation for the ship to model correlation allowance DCF, as a function of ship Reynolds number ReS is provided:

DCF = (14.77 – 0.7438 ln ReS) .10-3



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An allowance of 3.5% per screw (including shaft and bracket and rudder) is superimposed on the naked hull total resistance. The effect of LCB shift has been investigated only for the members of the parent model group (2nd group). Finally, values for the propulsive coefficients w, t and ?R are provided. AMECRC systematic series

These series were developed at the Australian Maritime Cooperative Research Centre (AMECRC). The series consists of 14 semi-displacement round-bilge, transom-stern models with straight entrance waterlines and buttock lines, based on the MARIN systematic series of High-Speed Displacement Hull Forms (HSDHF), with which they share the parent hull. The hull forms of the series can be used as workboats, launches or corvettes.

Following the policy of HSDHF series, AMRCRC does not publish the resistance results but only the description of the series and some regression formulae correlating geometrical characteristics with the varied hull form parameters (Bojovic, 1997). Only for the parent model, which was selected on the basis of its superior seakeeping qualities, MARIN published the hull geometry (Fig. 4) and the test results.

All members of the series share the form parameters of Table 5. Their common waterline length LWL =1.60 m was quite small, due to the size of AMECRC towing tank. On the other hand, the parameters of the parent model of both AMECRC and HSDHF series along with the range of their variation are given in Table 6. It is obvious that the parent model of the series doesn’t possess intermediate form parameters. Further to calm water resistance tests performed for speeds 0.4 to 4.0 m/sec (respective Fn = 0.10 to 1.00), seakeeping tests in regular head waves for speeds corresponding to Fn = 0.285, 0.570 and 0.856 have been carried out.

Figure 4: Body plan of the parent model of HSDHF and AMECRC series



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Table 5: Form Parameters common to all models of AMECRC series

Form Parameter Value Prismatic Coefficient CP = ∇/(AM LBP) 0.626 Waterplane area coefficient CWP 0.796 Transom Area / Maximum Sectional Area AT/AX 0.296 Transom Beam / Maximum Beam BT/BX 0.964 LCB/LBP (forward of transom) 0.446

Table 6: The parent model and the range of parameters in AMECRC & HSDHF series

Parameter Parent Model AMECRC Series

HSDHF series

LWL/BWL 8.00 4.00 – 8.00 4.00 – 12.00 BWL/T 4.00 2.50 – 4.00 2.50 – 5.50 CB 0.396 0.396 – 0.500 0.350 – 0.550

Bojovic (1997) describes the way the results are presented. AMECRC produced multi-parametric

plots of the non-dimensional parameters CR and RR/W (W = weight) using iso-LWL/BWL, BWL/T and CB curves per speed, expressed in terms of Fn and Fn∇, respectively. Furthermore, a multiple regression analysis and two non-linear estimation techniques have been applied on the results. The NTUA Series of double-chine hull forms

Many years ago, Savitsky et al (1972) proposed a novel “High-Speed Planing Hull for Rough Water” with wide transom, warped planing surface, double chine and very fine bow lines. Some years later two high-speed craft were tested in rough seas, one with the novel hull form and the other with a traditional hard chine. The findings of Blount and Hankley (1976), who presented the results of the full-scale trials, were very favorable for the novel hull form, although this was not stated explicitly! Actually, the CG acceleration data of that craft could be compared favorably with traditional hard-chine craft at twice the sea intensity.

During the early 90s, various versions of this aforementioned hull form have been extensively constructed especially for European short-sea shipping. The advance of structural technology enabled the construction of large ships, with length in the 100 m range, with quite lighter (non-dimensional) displacements than the original rather small craft tested in the States, operating in the “pre-planing” region, i.e. at speeds corresponding to Fn greater than 0.40 and mostly in the region of 0.60.

On the basis of that hull form a systematic Series of double–chine, wide transom hull form with warped planing surface has been developed at the Laboratory for Ship & Marine Hydrodynamics (LSMH) of the National Technical University of Athens (NTUA). The Series are appropriate for the preliminary design of fast monohull ships in the sense defined in the introduction, operating at high but pre-planing speeds (respective Fn =0.55 to 0.85-0.90) These limits correspond to 33 and 40 kn for a 40-m and a 140-m vessel, respectively, while a 20-m vessel does 25 kn when running at Fn = 0.90. Thus, the usefulness of the series for vessels of any substantial size is obvious. However, the parent model which has been tested at DERA (now QINETIQ) premises up to a speed corresponding to Fn = 1.80, demonstrated a very satisfactory performance at these very high speeds.



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Figure 5: Lines plan of the parent hull form of the NTUA systematic series (the body plan has been scaled up by a factor of three).

The NTUA double-chine series ended up consisting of five (small) models with LOA/BM = 4.00, 4.75, 5.50, 6.25 & 7.00 and five larger versions of the previous models to accommodate the very light displacements. Each small model (and/or its larger version) was tested at six displacements

corresponding to a volume of displacement coefficient CDL= ∇/(0.1.LWL)3 = 1.00, 1.61, 22.3, 3.00, 3.61 and

4.23, to cover the needs of both large and small fast ships. The lines plan of parent form of the Series with L/B = 5.50 is shown in Fig. 5. Its longitudinal distribution of deadrise angle is shown in Fig. 6.

Grigoropoulos and Loukakis (1999, 2002) presented the resistance characteristics for the series (residuary resistance coefficient CR, running trim and dynamic CG rise). CR values were estimated on the basis of static LWL and wetted surface, following a demonstration that this is sufficient for these series. In addition, existing full-scale data and Laboratory seakeeping experiments, currently underway, in regular and random head waves indicate excellent rough water performance characteristics for the Series. Their results will be published in the near future. To enhance the usefulness of the series, it was decided to slowly construct an extensive series both for resistance and seakeeping, bearing in mind that no other experimental resistance series contains systematic tests in waves and no other systematic resistance series for fast ships contains information about operation at very light displacements. It should be mentioned here that the ships this series refers to, exist gratis to recent advances in Marine Engines (Diesels with very high power density and Marine Gas Turbines) and Propulsion Devices (extensive use of water jets).



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10

20

40

30

50

60

DE

AD

RIS

E A

NG

LE (D

EG

.)

0 10.25

X/L OA

0.5 0.75

STERN

Figure 6: Deadrise angle vs x/LOA

As it is obvious in Fig. 7, the series have very good resistance trend as speed increases, together with negligible squat and very small dynamic trim angle in the region of Fn = 0.60 - 0.90. One 38-m long, 30 kn passenger vessel based on the series operates in South Italy.

Although NTUA is a University and the project was mostly un-sponsored, the experiments were conducted very carefully. Cross-comparison of many results from the small models, the large models and the large (parent) model in a different Towing Tank support this claim.

The basic advantage of the NTUA double chine Series is that they are based on a parent hull form of known seaworthiness and good maneuvering characteristics. This fact has been verified by sea trials as well as in the Ship and Marine Hydrodynamics Laboratory of NTUA (see e.g. Grigoropoulos and Loukakis, 1995).

Figure 7: Resistance, C.G. rise and dynamic trim of the parent hull form in the pre-planing region.

0.00 0.20 0.40 0.60 0.80 1.00Fn

0.00

0.04

0.08

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R /

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n )

, DY

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TR

IM [d

eg],

C

.G.-R

ISE

/Lw

l [%

]L/B = 5.5, C = 1.0

R /?

DYNAMIC TRIM

C.G.-RISE/Lwl

R /(?*Fn )

DL

2

2

2

T

T

T



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Another advantage of the NTUA Series is that its results form an extensive grid, which contains

very light loading conditions, i.e. values of CDL = 1.00, 1.61 & 2.23, which are absent in other systematic resistance series appropriate for monohull ships in the aforementioned Fn range. This feature makes the Series useful for the preliminary design of modern fast ships, with lengths of the order of 100m and displacements of the order of 1000 mt.

The resistance characteristics of the Series compare favorably with other hull forms appropriate for the pre-planing Fn range, while the proposed hull form possess also a wide transom, present in all modern designs of fast monohull ships.

Limited experiments in the planing Fn range, show that the parent hull form behaves very well and in that region, as its inventors intended. 3. Modifications to improve Calm Water Performance of Fast Monohulls

High-speed monohulls discussed hereafter are those operating in a Fn range of 0.4 to 1.1, which can be of semi-displacement or planing hull type. The fast planing runabouts are outside the scope of this discussion, which focuses on the larger vessels, up to a length of 150 m.

The semi-displacement hull experiences a degree of dynamic lift, and its underwater shape is

rounded with straight entrance waterlines and buttock lines and a transom stern. The planing hull possesses, in addition, one or more hard chines and straight sections to take advantage of the extra dynamic lift available at higher speeds. Finally, some methods of improving the performance of a given hull, as the fitting of stern wedges or flaps and of spray rails are reviewed and discussed.

High-speed monohulls are extensively used for short sea passenger/car transportation, near shore patrol missions, as workboats and as private yachts. Firstly, the effects of various stern wedge configurations on the calm water performance of the above model are experiment ally investigated in a systematic way for volumetric Froude numbers up to 3.0. On the basis of the tests, the necessity of using stern wedges in planing hulls is discussed.

As Savitsky (1964) has demonstrated, the performance of prismatic planing hulls in calm water is dominated by the displacement and its longitudinal distribution expressed by LCG, the breadth over chine and the deadrise angle. In the case of non-prismatic hulls with varying deadrise, the respective longitudinal distribution of breadths over chines and deadrise angles should be taken into account. For any given combination of these design parameters the hull is planing at any speed with a specific dynamic trim. Thus, the problem of optimizing the design of a planing hull form is reduced to finding out the optimum combination of these parameters, resulting in reduced horsepower requirements. The achieved dynamic trimming angles in that case, are closely associated with the specific hull form, so that it could be said that, instead of seeking for reduced resistance, the designer aims at the determination of the associated dynamic trim over speed curve.

Since the displacement and the LCG are usually pre-set by the user’s requirements, the main task of the designer is to determine an optimized combination of longitudinal distributions of breadths and deadrise angles, resulting in reduced calm water resistance. When this objective cannot be achieved, stern wedges or adjustable trimming tabs should be used to reduce the running trim by stern of a planing hull. The stern wedges are simple constructions and they can produce high lift forces, resulting in an improved hydrodynamic performance of the vessel in a limited speed range. On the contrary, the trimming tabs permit the fine tuning of the dynamic trim to its optimum value, corresponding to the minimum resistance for a given speed. However, their constructional details do not allow for very heavy loading.

Grigoropoulos and Loukakis (1995, 1996) fitted spray rails and stern wedges, respectively, on the

parent model of the NTUA series without clear (positive or negative) effect. They tested the model at

speeds corresponding to Fn up to 1.10 using stern wedges with lengths 2, 5, 7.5 and 10% of LWL. The



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optimum wedge length was found to fall in the range of 2% to 5% of LWL. At each wedge length, the

model was fitted with different span-beam ratio wedges, concluding that the full span wedges are the

most efficient. One year later (1997), the former of the authors combined the effect of stern wedges with

spray rails on the same hull form and with similar (disappointing) results. It seems that the model without

the wedges runs at a nearly optimum trim. Grigoropoulos and Loukakis (2001) drew similar results when

they investigated the effect of static trim on the performance of the parent model of NTUA series.

On the contrary, the investigations of Grigoropoulos and Damala (1999) were more successful. They investigated experimentally the combined effects of spray rails and stern wedges on the calm water performance of three high-speed round-bottom hull forms. The calm water performance of the three models of offshore patrol vessels (OPV), depicted in Fig. 9, has been optimized via stern wedges and one or two spray rail series in the bow region (Müller-Graf, 1991). The three models have been tested up to speeds corresponding to Fn = 1.00, 0.75 and 0.60. The extensive investigation aimed at determining the particular effects of the aforementioned appendages on the resistance of these models in conjunction with the modification of their displacement, trimming angle and vertical location of the centre of gravity. The experimental results were thoroughly analysed in order to discuss the necessity of fitting one or two series of spray rails in combination with stern wedges, and to specify the most efficient design parameters, such as the form and location of these appendages (Lindrgren and Williams, 1968)

Usually the designer of a fast monohull has to achieve a relatively high speed for a displacement and LCG of the vessel determined by the owner’s requirements. In this task, his work is supported by two kinds of appendages, the spray rails and the stern wedges. Both of them produce lift and at the same time they affect the dynamic trim of the vessel in a contradicting way. Furthermore, the extensive testing of the three models with different hullform, led to the following major conclusions:

Figure 8: Body plans of the tested models.

OPV-2

Knuckle - Spray rail 1

Knuckle

∇

Spray rail 1 Spray rail 2

Knuckle OPV-1

∇

Spray rail 1

Spray rail 2

OPV-3

∇



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• The efficiency of spray rails, when fitted according to the guidelines provided in the literature is

restricted at Fn > 0.85. • Stern wedges reduce the resistance of semi-displacement practically in the whole range of operation

(Fn > 0.40) • The lift generation seems to dominate the influence of the wedges on the resistance of high-speed

vessels. On the other hand, wedges reduce the trim by stern at speed, thus partly counteracting the effect of lift.

• Finally, stern wedges improve the propulsive performance of fast monohulls, leading to even higher attainable maximum speeds.

Finally, Karafiath and Fisher (1987) investigated the effect of stern wedges on the propulsive

efficiency of large naval ships. Since analytical results of the hydrodynamics of the wedge effect on semi-displacement hull form were not available, they combined experimental data with analytical results derived using a potential flow code (Dawson, 1979) to conclude that a properly designed stern wedge may lead to a 6% reduction in the delivered power. However, they claimed that the modification of the flow field around the after body of the ship by the wedge, and not the trim change, causes the principal changes in powering performance. More recently, Cusanelli and Karafiath (2001) reviewed the efforts in David Taylor Model Basin, since 1989 to design stern wedges (ending at the transom) and flaps (extending aft of the transom) for improving the performance of destroyers and frigates as well as 52-m long patrol coastal boats. In the later case, reduced span flaps were fitted. 4. Improvement of both Calm and Rough Water Qualities of Fast Monohulls

In the previous section some local modifications and add-ons have been presented to improve the performance of a fast monohull in calm water. Local modifications, however, cannot affect the seakeeping characteristics of ships. Only a variation of the main (global) hull form parameters during the conceptual design phase can significantly affect the seakeeping performance of a ship.

Along these guidelines Keuning and Pinkster (1995) proposed the Enlarged Ship Concept (ESC). The authors presented the ESC using as “base” design an existing and quite successful design of patrol boat (Stan Patrol 2600), which they lengthened by 25% and 50%, whilst keeping all other design parameters, such as beam, speed, payload, functions, etc. constant. Although the calculated building cost is increased by 6% in the latter case, the advantages of the enlarged ship compared to the base boat are: § The Fn is reduced for the same speed (this is advantageous for vessels sailing at speeds lower than

those corresponding to the hump of CR coefficient curve). § The L/B and L/∇1/3 ratio are increased, which is beneficial both for calm water resistance and

seakeeping. § The pitch radius of gyration is decreased. § The position of the prime working areas on board is optimized with respect to vertical motions.

Keuning and Pinkster (1997) and Keuning et al (2001) further refined the concept by proposing two modifications of the bow shape, over some 25% of the length, both below and above the still waterline, the TUD 4100 and the Axe bow, in order to improve the seakeeping behaviour. The aim of this bow modification was to reduce the non-linear hydrodynamic forces in particular at the fore ship (Fig. 9).



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Figure 9:

Bow refinement of ESC for improving seakeeping performance. Both bows (TUD 4100 to a lesser extent) result in: § Reduction of the flare of the bow sections § Narrowing and increase of length of waterlines § Deepening of the fore foot § Increase of freeboard.

Keuning et al (2001) studied the behaviour (i.e. heave and pitch motions) in both head- and following irregular waves of the three systematic bow shape variations. They also investigated the manoeuvring characteristics for these variations. Because one of the serious concerns about these proposed bow modifications lies with a possible increased sensitivity of the ships with the sharper and deeper bows to broaching in following waves, they also studied this aspect of the behaviour in waves.

The results of the comparison between these three designs (with this increasing change in bow shape) lead to the conclusion that the seakeeping performance of AXE 4100 hull form is superior to that of TUD 4100, which in turn is better than the ESC 4100. The comparison was made in terms of significant or extreme vertical acceleration in the bow region and slamming. The authors consider extreme values as more critical for limiting the operation of the vessel. On the contrary manoeuvring characteristics and broaching tendency of the modified hull forms are inferior.



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5. New trends in the design of fast monohulls

Paragon Mann designed a hybrid slender, wave piercing hull form, denoted as VSV, which is appropriate for patrol missions. This hull form possesses a very high L/B ratio (L/B > 5.50), a sharp bow profile with a very low entrance angle and wedge-shaped waterlines. The hull form was tested in the 380-ft towing tank of U.S. Naval Academy Hydromechanics Laboratory (Schleicher et al, 1997) against a conventional planing hull form. The two models had the same waterline length and payload, while the displacement of the wave piercing hull form was 20% lower. The hybrid model exhibited lower resistance that the conventional hard-chine one, especially in the pre-hump region and no porpoising tendency. The LCG position was critical for both the improved calm water resistance and dynamic stability characteristics. Furthermore, this hull form has reduced seakeeping responses at high speeds, low radar signature and very good manoeuvring characteristics. Two sizes of this hull form are currently produced by Halmatic, with LOA = 16 and 22.86 m (Fig. 10) operating at speed in the 50 kn range.

Figure 10: Artistic view of Halmatic VSV-22m patrol boat

On the other hand, in the case of large monohulls (frigates, littoral combat ships, cruisers and passenger ferries), impact loads (bow slamming) result in severe distress of the structure in the bow region. Thus, the designers proposed to reverse the inclination of the bow stem profile resulting in a wave-piercing configuration, which reduces significantly bow fatigue due to wave loads. Furthermore, this tumblehome hull form design offers significant power savings due to reduced calm water resistance, while it is also critical to meeting low Radar Cross Section (RCS) signature objectives. The concept has already been incorporated in the new four-year US Navy Project awarded in 2001 to Northrop Grumman led Gold Team, denoted as DD(X). The initial orientation of the project, which is the successor of US Nave Project DD21 Zumwalt, is the design of a high-performance, low operational frigate (Figure 11).



333

Figure 11: Artistic view of US Navy DD(X) design of multi-mission surface combatant. 6. Discussion - Conclusions

In this report the outline of three new round-bottom and one double-chine hull form Series is presented. All series are wide-transom and appropriate for naval ship applications ranging from relatively small fast patrol boats to large ships like corvettes and destroyers. The former operate at speeds corresponding to Fn in excess of 0.50, while the latter operate at speeds before and in the vicinity of the hump (Fn = 0.40 to 0.50).

Since, the performance of these vessels in the above speed range is very sensitive to local modifications and appendages fitted, the application of stern wedges, flaps and adjustable trimming tabs, as well as spray rails was presented. The combination of these appendages adjusts the trim of the vessel to the optimum one (the one with the minimum resistance), while they reduce the running displacement by offering lift, especially at the higher speed range.

High-speed bow bulbs also have been recently fitted to large naval ships including combatants. Their applicability highly depends on the replacement of the conventional sonar devices accommodated in bow domes by more compact instrumentation fitted at openings in the bow region of the keel. Cusanelli (1994) developed a bow for a naval surface combatant by integrating a hydrodynamic bulb into an existing bow which houses a sonar dome. He evaluated many alternative bow design concepts, and conducted preliminary model tests to assist with the sizing and placement of the selected bulb concept. The initial bulb design developed and tested, reduces ship resistance by 3-7% at the maximum and the cruise speed, respectively, increasing, thus, the range. Furthermore, provides housing for auxiliary sonar systems. Finally, two novel monohull designs are presented, one appropriate for small patrol boats and the other for large surface combatants. The former combines a very slender bow with a wide transom, while the latter possesses a tumblehome bow form reduces the Radar signature.



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Nomenclature

CDL = ( )3WLL1.0∇ , the volume of displacement coefficient

CR = )V WS (R 22

1R ⋅ρ , residuary resistance coefficient

CFS frictional resistance coefficient for the ship CTS total resistance coefficient for the ship DCF ship to model correlation allowance CTS = CR + CFS +DCF ∇ Volume of displacement ? Displacement EHP Effective Horsepower

Fn = WLgLV , Froude number

LOA overall length LWL waterline length at rest M = LWL/∇

1/3 RR residuary resistance RT total resistance ? water density T mean draught t dynamic trim, (positive by stern) V speed WS wetted surface at rest 7. References 1. Bailey, D. (1976). The NPL High Speed Round Bilge Displacement Hull Series: Resistance,

Propulsion, Maneuvering and Seakeeping Data, National Maritime Institute. 2. Beys, P.M. (1963) Series 63 Round Bottom Boats, Stevens Inst. Of Technology, Davidson

Laboratory, Rep. 949, April. 3. Blount, D.L. and Hankley, D.W. (1976). Full-Scale Trials and Analysis of High-Performance Planing

Craft Data, SNAME, Vol. 84, pp. 251-277. 4. Blount, D.L. and Fox, D.L. (1976). Small-Craft Power Prediction, Marine Technology Journal, Vol. 13,

No. 1, pp. 14-45, January. 5. Bojovic, P. (1997). Resistance of AMECRC Systematic Series of High-Speed Displacement

Hullforms, IV Symp. On High-Speed Marine Vehicles HSMV, pp. 4.19-4.35, Napoli, Italy, 18-21 March.

6. Clement, E.P. and Blount, D.L. (1963). Resistance Tests of a Systematic Series of Planing Hull Forms, Transactions SNAME, Vol. 71, pp. 491-579.

7. Cusanelli, D.S. and Karafiath,G. (2001). Advances in stern flap design and Applications, 6th Intl. Conf. on FAST Sea Transportation FAST ‘01, Southampton, U.K., 4-6 September.

8. Cusanelli D.S. (1994). Development of a Bow for a Naval Surface Combatant which Combines a Hydrodynamic Bulb and a Sonar Dome, DTMB, American Society of Naval Engineers, Technical Innovation Symposium, September.

9. Dawson, C.W. (1979). Calculations with the XYZ free surface program for five ship models, Proc. of the Workshop on Ship Wave Resistance Computations , DTNSRDC, Bethesda, MD 20084, November.

10. Gamulin, A. (1996). A Semi-displacement Series of Ships, International Shipbuilding Progress, Vol. 43, No. 434, pp. 93-107.

11. Grigoropoulos, G.J. and Loukakis, T.A. (2002). Resistance and Seakeeping characteristics of a Systematic Series in the Pre-planing Condition (Part I), Trans. SNAME, Vol. 110, September.

12. Grigoropoulos, G.J. and Damala, D. (2001). The effect of trim on the resistance of high-speed craft, 2nd Intl. EuroConf. On High-Performance Marine Vehicles HIPER’01, Hamburg, 2-5 May.



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13. Grigoropoulos, G.J. and Damala, D. (1999). Effect of spray rails and wedges on the performance of semi-displacement hull forms, V Intl. Conf. On High Speed Marine Vehicle, HSMV ‘99, Capri, Italy, March.

14. Grigoropoulos, G.J. and Loukakis, T.A. (1999). Resistance of double-chine, large, high-speed craft. Bulletin de L’ Association Technique Maritime et Aeronautique ATMA , Vol. 99, Paris, June.

15. Grigoropoulos, G.J. and Loukakis, T.A. (1996). Effect of wedges on the calm water resistance of planing hulls, 1st Intl. Conf. on Marine Industry MARIND’96, Varna, Bulgaria, June.

16. Grigoropoulos, G.J. (1997). The use of spray rails and wedges in fast monohulls, IV High Speed Marine Vehicle Intl. Conf. HSMV’97, Naples, March.

17. Grigoropoulos, G.J. and Loukakis, T.A. (1995). Effect of Spray Rails on the Resistance of Planing Hulls, 3rd Intl. Conf. on FAST Sea Transportation FAST’95, Travemuende, Germany, September.

18. Holling, H.D. and Hubble, E.N. (1974), Model resistance data of Series 65 hull forms applicable to hydrofoils and planing craft, DTNSRDC, Report 4121, May.

19. Kanerva, M. (2001). From Handy Size up to Large Cruise Ferries, Elements Required to Design and Build Successful Configurations, Euroconference, Passenger Ship Design and Operation, Crete, October 2001, pp. 83-111.

20. Karafiath, G. and Fisher, S.C. (1987). The effect of stern wedges on ship power performance, Naval Engineers Journal, Vol. 99, No. 4, pp. 27-38, May.

21. Keuning, J.A., Toxopeus, S. and Pinkster, J. (2001). The effect of Bow Shape on the Seakeeping Performance of a Fast Monohull, 6th Intl. Conf. on FAST Sea Transportation FAST ‘01, Southampton, U.K., 4-6 September.

22. Keuning, J.A. and Pinkster, J. (1995). Optimization of the Seakeeping Behaviour of a Fast Monohull, 3rd Intl. Conf. on FAST Sea Transportation FAST ’95, Travemuende, Germany, September.

23. Keuning, J.A. and Gerritsma, J. (1982). Resistance Tests of a Series of Planing Hull Forms with 25 Degrees Deadrise Angle, International Shipbuilding Progress, Vol. 29, No. 337, September 1982, pp. 222-249.

24. Kracht, A. and Grim, O. (1960), Widerstand, Propulsion, Bewegung und Be-anspruchung schneller Verdrangunsfahrzeuge in glattem Wasser und in regel-maessigem Seegang, IFS-Bericht No. 167, Juli.

25. Kracht, A. (1996). Erweiterung der D-Serie: Breite, Schnelle Zweischrauben-schiffe, Versuchsanstallt fuer Wasserbau und Schiffbau, Technische Universitaet Berlin, Bericht Nr. 1267/96, January, Berlin, Deutschland.

26. Kracht, A. (1992). D-Serie, systematische Widerstands- und Lastvariations-versuche”, Versuchsanstallt fuer Wasserbau und Schiffbau, Technische Universitaet Berlin, Bericht Nr. 1202/92, Berlin, Deutschland.

27. Levander, K. (2001). Improving the ROPAX Concept with High-Tech Solutions, Euroconference, Passenger Ship Design and Operation, Crete, October 2001, pp. 45-62.

28. Lindrgren, H. and Williams, A. (1968). Systematic tests with small fast displacement vessels, including a study of the influence of spray rails, SNAME Diamond Jubilee Intl. Meeting, June.

29. Müller-Graf, B. (1991). The effect of an advanced spray rail system on resistance and development of spray of semi-displacement round bilge hulls, 1st Intl. Conf. on Fast Sea Transport. FAST 91, Trondheim, Norway, June

30. Murdey, D.C. and Simoes Re, A.J. (1985), The NRC hull form series - an update, MARIN Symp., October.

31. Oossanen, Van P. and Pieffers, Jan B.M. (1985), NSMB-Systematic series of high-speed displacement ship hull forms, MARIN Workshop on developments in Hull Form Design, Wageningen, October.

32. Radojcic, D., Grigoropoulos, G.J., Rodic, T., Kuvelic, T. and Damala, D. (2001). The Resistance and Trim of Semi-Displacement, Double-Chine, Transom-Stern Hull Series, FAST ’01, Southampton.

33. Savitsky, D., Roper, J. and Benen, L. (1972). Hydrodynamic Development of a High Speed Planing Hull for Rough Water, 9th O.N.R. Symposium, Paris, August.

34. Savitsky, D. (1964). Hydrodynamic Design of Planing Hulls, Marine Technology, SNAME, Vol. 1, No. 1, October 1964, pp. 71-95.

35. Schleicher, C., Schleicher, D. and Zseleczky, J. (1997). Investigation of a hybrid wave piercing planing hull form, 4th Intl. Conf. on Fast Sea Transport. FAST 97, Sydney, Australia, July 21-23.



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36. Schmitke, R.T., Glen, I.F. and Murdey, D.C. (1979), Development of a frigate hull form for superior seakeeping, Eastern Canadian Section, SNAME, April.

37. Yeh, H.Y.H. (1965), Series 64 resistance experiments on high-speed displacement forms, Marine Technology, Vol.2, No.3, July.



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APPENDIX 9.9

WASTE STREAM CATEGORIES



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In order to establish a common reference for defining waste management policies, and using the MARPOL 73/78 Convention as a reference, SWG/12 categorized waste stream as follows.

Table 9.9-I: Waste stream MARPOL 73/78 discharge criteria (AMEPP-4, tables 3A, 3B, 3C):

Liquid waste Area

Oily water and ballast < 15 ppm oil, discharge is allowed; in ports and inland waters no discharge except if ballast with less than 15 ppm oil.

Sewage < 4 nm discharge prohibited; 4-12 nm or certain areas discharge is allowed after comminute and disinfect; > 12 nm, discharge allowed.

Grey water Discharge is allowed except in specific areas.

Solid waste Outside MARPOL Special Areas In MARPOL Special Areas

Food > 12 nm discharge is allowed ( > 3 nm if comminuted or ground)

> 12 nm discharge is allowed

Plastic Discharge prohibited Discharge prohibited

Floating dunnage, lining, packing materials

> 25 nm offshore Discharge prohibited

Paper/cardboard > 12 nm discharge is allowed ( > 3 nm if comminuted or ground)

Discharge prohibited

Metal > 12 nm discharge is allowed ( > 3 nm if comminuted or ground)


Glass > 12 nm discharge is allowed ( > 3 nm if comminuted or ground)


Medical waste Discharge prohibited Discharge prohibited

Hazardous substances Discharge prohibited Discharge prohibited

Air emissions

ODS Discharge prohibited

NOx Associated with engine and fuel oil requirements

SOx Associated with engine and fuel oil requirements

VOC Regulations applying specifically to tankers

In can be noted, from the summary in Table 9.9-I, that liquid waste discharge is generally allowed after some form of treatment in order to reduce the concentration of contaminants.

On the other hand, and with the exception of food, solid waste discharge is prohibited in the special areas. Outside the special areas, and after separate processing of medical and hazardous waste and plastics, solid waste must be comminuted or ground, so that discharge may be allowed.



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The legal frame which sets the requirements for maritime environmental protection rules and regulations applicable to ships is the International Convention for the Prevention of Pollution from Ships of modified by the Protocol of 1978 (and generally known as the MARPOL 73/78 convention) and amended by the Protocol of 1997. This convention consists of:

a) Protocol I – Provisions concerning reports on incidents involving harmful substances. Adopted in 1973, amended in 1985 and 1996, fully into force by 1 January 1998.

b) Annex I – Regulations for the prevention of pollution by oil. Adopted in 1983, amended in 1986/87/90/91/92/94/97/99 and 2001, fully into force by 1 September 2002.

c) Annex II – Regulations for the control of pollution by noxious liquid substances in bulk. Adopted in 1978, amended in 1985/87/89/90/92/99, fully into force by 1 January 2001.

d) Annex III – Regulations for the prevention of pollution by harmful substances carried by sea in packaged form. Adopted in 1992, amended in 1992/94 and 2000, fully into force by 1 January 2002.

e) Annex IV – Regulations for the prevention of pollution by sewage from ships. Not yet into force, but adopted by 81 states.

f) Annex V – Regulations for the prevention of pollution by garbage from ships. Adopted in 1988, amended in 1989/90/91/94/95 and 2000, fully into force by 1 March 2002.

g) Annex VI – Regulations for the prevention of air pollution by ships. Adopted with the Protocol of 1997, but not yet into force.

The rules and regulations of MARPOL convention, together with national legislation of NATO countries, were incorporated into operational procedures and design guidance by NATO under the work of AC/141 SWG/12 “on Maritime Environmental Protection”, which is considered NATO/PfP unclassified. Specialist Working Group 12 team focused on the issues of annexes I, III, IV, V and VI, because the subject of annex II (noxious liquid substances in bulk) is generally not applicable to naval operations. Nevertheless, most NATO countries do not consider the issues addressed in annex VI to be important in naval vessels operation as they relate mostly to poor quality fuel and propulsion equipment. The following Allied Maritime Environmental Protection Publications (AMEPPs), presently into force, constitute the main frame for naval architects and marine engineers working in behalf of NATO navies:

a) AMEPP-1 Edition 4 – NATO naval forces policy for pollution reduction. Adopted by NATO countries in August 2002.

b) AMEPP-2 Edition 2 – National navy regulations for the disposal of waste. Adopted by NATO countries in October 1994.

c) AMEPP-3 Edition 3 – Shipboard pollution abatement equipment catalogue. Adopted by NATO countries in February 2001.

d) AMEPP-4 Edition 2 (ANEP-59) – Guidance for the integration of maritime environmental protection (MEP) functional requirements into a ship design. Adopted by NATO countries in January 1999.

e) AMEPP-5 Edition 1 – Alternative non-ozone depleting solvents/cleaning agents. Adopted by NATO countries in August 1995.

f) AMEPP-6 Edition 2 – Hazardous material offload guide. Adopted by NATO countries in April 2002.

g) AMEPP-7 Edition 2 – Glossary of terms and definitions used in the AMEPP series. Adopted by NATO countries in December 1999.

All of the AMMEP series may be considered to be fully or partially applicable to small ship design, as they relate to the compared practices and regulations in NATO countries regarding the issues of ship-generated pollution addressed in MARPOL 73/78. SWG/12 is a very active working group, and they



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have been revising the AMMEP series, which as a consequence may be considered to be quite reasonably up-to-date.

Both AMMEPs 1 (NATO naval forces policy for pollution reduction) and 2 (National navy regulations for the disposal of waste) are fully applicable to small ship design, and of mandatory compliance to small ship designers as they define both the national legislation in force and the procedures adopted by each one of the national navies. It may be noted that the basis of national legislation is always MARPOL 73/78 for all NATO countries, with some specific regulations added.

On the other hand, the scope of applicability of AMMEP-3 (Shipboard pollution abatement equipment catalogue) is directed mainly towards blue waters navies (and therefore to frigate-type vessels), and the equipments described tend to have significant weight, space and services requirements. It could be a point of interest, in the ST-SSD recommendations to NG/6, the enlargement of the scope of AMMEP-3 to incorporate technical descript ions and data of smaller equipment, designed to small crew requirements.

AMMEP-4/ANEP-59 “Guidance for the integration of maritime environmental protection (MEP) functional requirements into a ship design” is a very good reference for small ship designers. It includes a summary of environmental regulations for waste streams, which it separates primarily into solid waste, liquid waste and air emissions; it presents data for waste generation rates, for selection and sizing of waste processing equipment; it refers the most typical waste management strategies and scenarios currently applicable to NATO navies; it sets functional requirements for waste management systems; it analyses design constraints and shipboard integration aspects; and it provides recommendations for waste management practices, but these clearly conceived for the main purpose of assisting frigate type ship design AMMEP-4/ANEP-59 is, undoubtedly, an extremely important tool, in what MEP aspects are concerned, both for new ship design and retrofit design.

AMEPP-5 (Alternative non-ozone depleting solvents/cleaning agents) is of universal use within NATO: Therefore, it does not apply specifically to small ship design. On the other hand, AMEPP-6 (Hazardous material offload guide) is basically a procedures’ manual, and AMEPP-7 (Glossary of terms and definitions used in the AMEPP series) is a support document.

As a conclusion, it was noted that SWG/12 has produced very high quality work, with a wide scope of applicability for the ship designer. The structure and organization of the series of AMEPPs currently in force seems to be easily adaptable to incorporate more small ship design issues, which would be much simpler and easier than producing separate documents.

In a technological area that has been evolving rapidly, it is also relevant to note that all documents of the AMMEP series are recent or have been recently revised, and therefore they may be considered to be up-to-date.



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The problem of small ship environmentally sound operation is currently being addressed in a significant number of countries. SWG/12 work also addressed the specific issues of MEP compliance for small ships; a very interesting paper was presented to SWG/12 in the April 2003 meeting by the Royal Australian Navy (RAN) delegation with the MEP equipment fit of five different type of small naval ships from 245 to 2550 tonnes (in the full-load condition), providing a reasonably wide scoped sample. All ships in the example list were originally fitted with MEP equipment or retrofitted, so that they all are said to comply with RAN MEP criteria. The data provided are summarized in the following table:

Table 9.9-2: Waste management strategies in force onboard RANs small ships:

Type of ship Landing craft heavy

Mine Hunter Coastal

Hydrographic survey ship

Patrol Boat Patrol Boat (in design stage)

Full-load disp.

530 tonnes 720 tonnes 2550 tonnes 245 tonnes Approx 350 tonnes

Crew 13 36 46 24 21+20

Commissioning

1971 to 1974 1999 to 2002 2000 1980 to 1984 -

Oily water and ballast

Wet bilges with pump collection to 0,46 m3 settling tank; 0,380 m3 /hour OWS with dirty oil storage tank; oil content meter checks discharge overboard

Dry bilge; leaks and used oil to sludge tanks, OWS, 0,41 m3

waste oil tank and 1,14 m3 oily water holding tank; oil content meter checks discharge overboard

Dry bilge; leaks and used oil to oily water holding tank, OWS, sludge tank; oil content meter checks discharge overboard

Wet bilges with pump collection to oily water settling tank, OWS, oil content meter checks discharge overboard

Dry bilge and bilge collection pump, OWS, sludge tank for oily waste; oil content meter checks discharge overboard;

Sewage Seawater, gravity collection; 0,85 m3 surge tank; STP by maceration and disinfection until treated effluent may be discharged overboard

Fresh water, vacuum collection (2 pumps); STP by maceration and disinfection with sludge tank for ashore discharge

Fresh water, 2,5 m3 vacuum collection tanks 1,5 m3 surge tanks, 2 STP by maceration and disinfection

4 chemical recirculating and sewage holding tank

Gravity and/or vacuum collection; STP

Grey water To STP; may be diverted overboard

7 small collection tanks connected to STP

7 small collection tanks connected to STP

Direct discharge overboard or collection tank

collection to STP

Food Storage bins Pulpers in galley and scullery to STP

Pulpers in galley to discharge overboard or refrigerated store

Discharge overboard where acceptable

Storage for 7 days

Paper, plastic, metal,

Storage bins Storage bins and compactor

Bins and compactor, dry

Storage bins Segregation and dry



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glass garbage store garbage store

Floating packs and lining


Bins and compactor, dry garbage store

Storage bins Segregation and dry garbage store

Medical and hazardous


Bins and compactor, dry garbage store

Storage bins Segregation and dry garbage store

Air emissions No data No data No data No data No data

The tendency in the RAN, in accordance with the results in Table 9.10-2, is to move towards the inclusion of a waste management plan in the ship design stage. Waste management strategies are addressed very early in the design, as well as the issues of minimizing waste generation at source and optimizing collection, separation, processing and storage.

References:

a. Lawry, Steven: “Marine Environmental Protection for Small RAN (Royal Australian Navy) Ships”. Presentation to SWG/12 in the April 2003 Meeting.



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APPENDIX 9.10

WORKED EXAMPLE OF OPV & FPB WASTE STREAMS



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For the analysis of the waste management problem, SWG/12 categorized waste stream as follows.

Table 9.10-I: Waste stream categories (AMEPP-4, tables 3A, 3B and 3C):

Liquid waste Oily water Bilge waters contaminated with oil leaks Sewage Toilet-originated stream Grey water Washing-originated stream (showers, floor washing, laundry, etc.) Solid waste Food Biologically degradable stream, particularly from meals and food preparation Plastic Plastic containers; a little percentage of organic matter is acceptable, but no

hazardous substances are allowed, even in very small quantities Paper/cardboard Paper and cardboard packages of all types; a little percentage of organic matter is

acceptable, but no hazardous substances are allowed, even in very small quantities Metal All types of metal waste; a little percentage of organic matter is acceptable, but no

hazardous substances are allowed, even in very small quantities Glass Glass debris; a little percentage of organic matter is acceptable, but no hazardous

substances are allowed, even in very small quantities Medical waste All waste from medical activities, susceptible to be associated with disease or

chemical contamination Hazardous substances

All types of hazardous substances except radioactive material (not considered in the waste stream handling process) and all packages, containers, fabrics, contaminated with them, even in very small quantities

Air emissions ODS (ozone depleting substances) Leaks from refrigeration plants NOx (nitrogen oxides) Combustion engine emissions SOx (Sulphur oxides) Combustion engine emissions VOC (volatile organic compounds) Leaks from fuel tanks, gas, crude or fuel oil holds

In practice, and by applying Table I to the waste stream of large and small naval ships, it may be noted that the most significant difference between frigate size and small naval ships, in what waste generation is concerned, is quantity. Even in small quantities, all types of waste are produced onboard small ships, and therefore the same principles studied by SWG/12 and made available to the NATO ship designers’ community by AMEPP series, apply.

Referring to waste stream volume, SWG/12 collected and analyzed data obtained from NATO ships. With this method, the average values of Table II were obtained for waste stream data. In is very important to note, however, that the sample used for obtaining this data is based in a majority of frigate-size vessels, and that separate data collection procedures would be necessary to tune these results to other ship sizes and types.



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Table 9.10-II: NATO ships average waste generation rates (AMEPP-4, table 4A):

WASTE STREAM RATE/PERSON (NATO AVERAGE) Liquid waste Kg/day Liter/day Oily water 4000 (frigate size, independent of crew) Sewage 40 (gravity) or 10-15 (vacuum) Grey water 120 Solid waste Kg/day Liter/day Food 0,665 1,6 Plastic 0,1 2,9 Paper/cardboard 0,45 2,1 Metal 0,127 1,1 Glass 0,15 1,3 Medical waste 0,009 0,2 Hazardous substances 0,024 0,9

Taking these values for a 1500 tonne OPV with 47 crew (35 plus 12 inspectors, government officials, cameramen or scientists) with a mission profile requiring 30 days of waste storage (the future Portuguese OPV, currently in the detailed design stage); and for a 100 tonnes fast patrol boat with 7 crew and a requirement for a mission time at sea of 8 days (the existing Portuguese coastal patrol boats of “Centauro” class), the following results were obtained:

Table 9.10-III: Waste stream for OPV and FPB examples

WASTE STREAM OPV, weight and volume FPB, weight and volume Liquid waste Kgs Liters Kgs Liters Oily water (see note 1) 30 000 30 000 1 600 1 600 Sewage (see note 2) 21 700 21 150 2 300 2 240 Grey water 169 200 169 200 6 720 6 720 Sub-total liquid waste 220 900 220 350 10 620 10 560 Solid waste Kgs Liters Kgs Liters Food 937,7 2 256 37,2 89,6 Plastic 141 4 089 5,6 162,4 Paper/cardboard 634,5 2 961 25,2 117,6 Metal 179,1 1 551 7,1 61,6 Glass 211,5 1 833 8,4 72,8 Medical waste 12,7 282 0,5 11,2 Hazardous substances 33,8 1 269 1,3 50,4 Subtotal solid waste 2 150,3 14 241 85,3 565,6 Total waste App 223 000 App 235 000 App 10 700 App 11 100 % of Full-Load Displacement 14,8% 10,7%

Note 1: using the operational experience of the Portuguese Navy, it was assumed that oily water stream should not exceed 1000 lts/day for the OPV and 200 lts/day for the FPB.

Note 2: calculations for OPV using vacuum system, and for FPB using gravity system.



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APPENDIX 9.11

WORKED EXAMPLE OF OPV & FPB RAS REQUIREMENTS



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For the analysis of the problem of shipboard habitability requirements, ANEP-24 includes an analysis of the storage spaces volume and weight requirements. The most important stores consumption rates applicable to RAS requirements are as follows.

Table 9.11-I: Typical Fresh Water and Stores Consumption Rates onboard NATO Surface Ships

Volume/(man*day) (m3) Weight/(man*day) (Kg)

Dry stores 0,003 1,4

Frozen stores 0,001 0,5

Vegetables 0,002 0,6

Fresh water (*) 0,2 200

Medical supplies 0,001 1

Note (*): Volume/man, for ship fitted with Reverse Osmosis plants (emergency potable water reserve).

In addition to these requirements, fuel consumption is generally the main concern of RAS. It is highly dependent, however, on the ship’s propulsion machinery fit and operational profile.

Using these data and fuel consumption estimates for a 1500 tonnes OPV with a crew of 47 and a mission profile of 30 days at sea and a 100 tonnes fast patrol boat with 7 crew/8 days at sea, the following results were obtained:

Table 9.11-2: Solid stores and fuel requirements for OPV and FPB total mission duration

OPV, weight and volume FPB, weight and volume

Liquid stores Kgs Liters Kgs Liters

Fuel consumption (*) 174 200 204 900 23 500 27 600

Potable water reserve 9 400 9 400 1 400 1 400

Solid stores Kgs Liters Kgs Liters

Dry stores 1 974 4 230 78 168

Frozen stores 705 1 410 28 56

Vegetables 846 2 820 34 112

Medical supplies 1 410 1 410 56 56

Subtotal solid stores 4 935 9 870 196 392

Total fuel and solid stores App 190 000 App 235 000 App 25 100 App 29 300

% of Full-Load Displacement 12,7% 25,1%

Note (*): Assuming that, for average mission, fuel consumption is 20% of maximum consumption (top speed and maximum hotel load).



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APPENDIX 9.12

EXAMPLE OF THE ROYAL AUSTRALIAN NAVY’S RAS ARRANGEMENTS ONBOARD SMALL SHIPS



349

The main reference for RAS arrangements onboard NATO ships, together RAS organization and procedures, and therefore setting a general legal frame for RAS altogether, is ATP 16, a allied tactical publication. This publication has evolved quite significantly since the days of cold war, becoming a multinational tactical publication open to non-NATO countries, and it is now ATP 16(D)/MTP 16(D).

Since RAS is a item essential to interoperability, the enforcement of national regulations has been generally limited to safety procedures – for example, in some navies it is prohibited to replenish simultaneously fuel and ammunition. ATP 16(D)/MTP 16(D) includes general descriptions of the RAS arrangements of the participating nation’s surface combatants and replenishment ships, and it provides guidance to both tactical and technical procedures.

Within the NATO organization, the following standardization agreements (STANAGs) currently apply to RAS:

a) STANAG 1010 – Specifications of water to be transferred to ships of NATO navies intended for use in boiler feedwater systems – NU (NATO Unclassified).

b) STANAG 1084 – Replenishment of fuel and water in harbor – NR (NATO Reserved).

c) STANAG 1199 – Reelable astern refueling rig for the conversion of merchant tankers -NU. d) STANAG 1217 – Standard requirements for the night transfer station marker box - NU. e) STANAG 1218 – Standard reception station arrangements designated to support up to 250 Kg

(550 pounds) transfer load - NU. f) STANAG 1222 – Single probe coupling - NU. g) STANAG 1232(ATP-43) – Ship towing - NU.

h) STANAG 1234 - Standardization of thread design for 65mm bore replenishment fitting -NU. i) STANAG 1235 – Standard requirements for the day transfer station marker - NU. j) STANAG 1310 – Design criteria for replenishment aspects of new construction naval vessels -

NU. k) STANAG 1328 – Standard distance line lighting - NU. l) STANAG 1357 – NATO standard F-44 hose coupling - NU.

m) STANAG 1384 – NATO standard replenishment at sea telephone connectors - NU.

Generally STANAGs are NATO Unclassified, and therefore fully open to PfP nations. They provide a number of significant contributions to ship designers; it may be noted that STANAG 1310 was produced for the dedicated purpose of assist ship designers in the integration of RAS-related issues into the design. STANAG 1310 is applicable to naval vessels with a length overall of 107 meters or more, but the concepts of the document may be reduced to a particular small ship design taking the particular requirements into consideration.

The applicability of a given set of the STANAGs above mentioned and the technical data contained in ATP16(D)/MTP16(D) depends heavily in the designer options of operational requirements and interoperability, since ATP16(D)/MTP16(D) describes in detail the RAS equipment fits and arrangements in NATO replenishment vessels.



Again, the Royal Australian Navy (RAN) was selected as an example:

Table 9.12-1: Summary of RAN small ships RAS capabilities, from ATP16(D)/AMP16(D) table AU2-1/1: Fuel rigs


Mine Hunter Coastal


Patrol Boat Patrol Boat (in design

stage)

Full-load disp. 530 tonnes 720 tonnes 2550 tonnes 245 tonnes Approx 350 tonnes

Crew 13 36 46 24 21+20

Commissioning 1971 to 1974 1999 to 2002 2000 1980 to 1984 -

Crane or derrick No No No data No No

STREAM (standard tension replenishment alongside method)

No Receiving ship arrangements

No data No No

Close in No No No data No No

Astern No No No data No No

Non-tensioned span wire

No No No data No No

VERTREP (vertical replenishment)

Receiving ship arrangements


No data Receiving ship

arrangements

No

Table 9.12.-2: Summary of RAN small ships RAS capabilities, from ATP16(D)/AMP16(D) table AU2-1/2: Transfer of solids and personnel


Mine Hunter Coastal


Patrol Boat Patrol Boat (in design

stage)

Full-load disp. 530 tonnes 720 tonnes 2550 tonnes 245 tonnes Approx 350 tonnes

Crew 13 36 46 24 21+20

Commissioning 1971 to 1974 1999 to 2002 2000 1980 to 1984 -

Crane or derrick No No No No No

Heavy jackstay No No No data No No

Light jackstay Receiving and delivering ship arrangements


No data Receiving and delivering ship arrangements

Receiving and delivering ship arrangements

Manila highline No No No data No No

STREAM (standard tension replenishment alongside method)

No No No data No No

In accordance with the previous tables, RAN small ships arrangements are very limited in what RAS is concerned.



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It can be noted that fuel replenishment arrangements are almost non-existing, which highlights a strategy for clearly separate roles between blue waters and coastal vessels; however, an emergency arrangement by vertical replenishment was considered.

The replenishment of solids is generally available with the light jackstay method.



APPENDIX 9.13

SIGNATURE MANAGEMENT



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1. ABSTRACT Over the years, the word stealth has been used more and more when discussing design and operational characteristics in military applications. New and more challenging techniques are constantly being applied to minimize signatures and thus hinder or delay detection and identification. Six Visby class corvettes have been ordered by FMV for the Royal Swedish Navy from Kockum Naval Systems, KNS. The first of its class, HMS Visby was launched in June 2000 and the commissioning trials starts spring 2001 The Visby Class Corvette is a multipurpose combat ship with 600 tonnes displacement. The hull is a sandwich construction of a PVC core with carbon fiber/vinyl laminate. The propulsion system consists of two identical CODOG machinery systems, each driving a KaMeWa 125 size WaterJet Unit. The Ship has special requirements for all signatures, i.e. Radar-, Hydro acoustics-, IR- and Magnetic Signature. The High Speed Machinery is twin Honeywell TF50A Gas Turbines, cantilever mounted side by side on the Main Reduction Gearbox housing. The Main Reduction Gearbox is a dual input high performance marine Gearbox designated MA -107 SBS, designed and manufactured by Cincinnati Gear Co. The Low Speed Machinery is a MTU 16 V 2000 TE90 Diesel Engine connected to the MRG by a power take in shaft. Combustion Air for the Gas Turbines is ducted from the shipside Air Inlet Screen (radar screen) via 3-stage separating filters. The Exhausts from the twin Gas Turbines are combined into one Exhaust Pipe and ducted to the ship transom above the WaterJet stream. Very little can be changed in the Gas Turbine, but high quality such as well balanced rotating part contributes to reduce the signatures. However, the main work has to be accomplished by the building shipyard in cooperation with the Gas Turbine manufacturer. The Main Reduction Gearbox is more available for changes to reduce signatures, but even for the Gearbox the building shipyard has to take design and installation measures. The HSM installation consist mainly of the Gas Turbine Engine, the Main Reduction Gear, WaterJets Unit and surrounding equipment such as main shaft, bearings and so on. The emphasis in this paper is on the GT, MRG and their effect on some of the more well known signatures i.e. RCS, IR, Hydro acoustics and Magnetic. Also some design measures are discussed.

.



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Figure 9.13-1. Visby Class Corvette

2. Main Data

The Visby class corvette main data are as follows: Length over all: Approx. 72 m Length between perpendiculars: 61,5 m Width: Max. 10,4 m Displacement, fully equipped: Approx. 600 tonnes Draft: Approx. 2,5 m Crew: 43 Hull: CFRP-sandwich High speed machinery: 4 Gas Turbines, total approx. 16 000 kW Low speed machinery: 2 Diesel Engines, total approx. 2 600 kW Propulsion: 2 WaterJet Propulsion units Generators: 3 Generators, total approx. 810 kW Acknowledgments



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3. Ship Missions The multi-role Visby class corvette ships can carry out a range of missions:

- Mine Counter Measures (MCM) - Anti Submarine Warfare (ASW) - Mine Laying - Surface Combat - Underwater Defense - Air Defense - Patrol service and escort duties

4. Propulsion Machinery 4.1 Overview The Propulsion Machinery for the Visby Class is of Combined Diesel or Gas Turbine (CODOG) type and consists of the following main components: - 2 x Diesel Engines MTU 16 V 2000 TN90 (Low Speed Machinery, LSM) - 4 x Gas Turbines Honeywell TF50A (High Speed Machinery, HSM) - 2 x Main Reduction Gears (MRG) Cincinnati Gear MA-107 SBS - 2 x WaterJet Units (WJU) KaMeWa 125S-2 The CODOG Machinery allows speed up to 15 knots for long periods with the Low Speed Machinery and a top speed of more than 35 knots with the High Speed Machinery. The HSM installation consist mainly of the Gas Turbine Engine, the Main Reduction Gear, WaterJet Unit and surrounding equipment such as main shaft, bearings and so on. The emphasis in this paper is put on the gas turbine, MRG and their effect on some of the better known signatures i.e. RCS, IR, Hydro acoustics and Magnetic. Also some design measures are discussed.

4.2 Gas Turbine Tf50a The Gas Turbine Engine, Honeywell TF50A is a two-shaft engine rated at 4000 kW maximum continuous power (MCP) and 4200 kW maximum intermittent power (MIP). The Engine modules are: Inlet Housing, Oil Sump, Accessory Gearbox, Gas Producer Module and Combustor Module. The Gas Turbine is digital controlled by a Full Authority Digital Engine Control (FADEC) and the Gas Turbine Propulsion Module System (GTPMS) is controlled/monitored by the Local Operating Panel (LOP).



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Figure 9.13-2. GT TF50A

4.3 Main Reduction Gear Ma-107 Sbs. The Visby Class Corvette utilizes two independent propulsion systems. At the heart of each propulsion system is the Cincinnati Gear MA-107 SBS MRG. The MA-107 SBS is a high-speed marine CODOG reduction gear unit. The MRG has three power inputs: two Honeywell TF50A gas turbine engines and one MTU Series 2000 diesel engine. All of the inputs are combined into one output shaft that drives a KaMeWa size 125 waterjet. The reduction gear is rated for 8,000 kW MCP during turbine mode and 1,300 kW MCP during diesel mode. The MRG is designed to accommodate two separate power paths consistent with the CODOG design. Both the turbine gearbox portion (HSM) and diesel gearbox portion (LSM) utilize a two-stage reduction and share the same second stage. The turbine gearbox portion is a parallel shaft, two stage, C-drive configuration (turbines and waterjet both located on the aft side of the MRG). The diesel gearbox portion is a parallel shaft, Z-drive configuration (diesel located forward and waterjet located aft of MRG). Synchronous Self Shifting (SSS) clutches are utilized throughout the MRG to ensure automatic transition between all operating modes (two turbine, single turbine, or diesel engine) and to prevent back-driving un-loaded components as much as possible. During the design phase, special consideration was given to housing design, gear configuration layout, balancing requirements, gear quality, and selection of tooth proportions to ensure a low noise design that would meet or exceed the specification. All gears in the propulsion torque path are single helical, case hardened and ground resulting in reduced weight, size and noise. Helical, high contact ratio, high accuracy (DIN 3961 Quality 4) gearing, employing profile and lead modifications, was selected in order to optimize mesh conditions and minimize transmission errors. The amount of transmission error is proportional to vibration and hence structure-borne and air-borne noise.



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The gear case is of cast aluminum construction. This design provides the rigid, low vibration structure required to support the rotating elements and externally applied loads without excessive weight. The gear case has been specially designed to ensure precise alignment of the gear elements and to allow cantilever mounting of the gas turbines. The gas turbines are completely supported by the gear case with no direct mounting to the vessel structure. This simplifies installation, ensures automatic alignment between the gearbox / turbine and minimizes the number of possible vibration transmission paths to ship mounting structure. In addition to minimizing the structure-borne and air-borne noise aspects of the MRG in the design and manufacturing stages, a resilient mount system is utilized to attenuate any vibration that could be transmitted to the ship structure. KNS utilized predicted vibration levels of the MRG and gas turbine in designing the resilient mounting system to meet hydro-acoustic signature requirements.

Figure 9.13-3. MRG MA-107 SBS

5. Signature Management FMV received the ship signature requirements from the Armed Forces Headquarter by the ”Tactical - Technical - Economical - Target Schedule”. FMV transformed the signatures levels to goals or requirements together with design-recommendations into the Design - Specification for the Ship Contract with the appointed shipyard, KNS. KNS thereafter incorporate the signature requirements in the Technical Specifications for the contracts with the various sub-contractors.



358

Early in the project, working-groups for different signatures and systems onboard were established. Participants in the groups are personnel from FMV, KNS, FOA, RSwN and special consultants. Signatures that are affected due to the HSM installation are as mentioned above. Many of the design solutions studied affects more than one signature. The FMV Program Manager has a Signature Coordinator assigned. The Signature Coordinators main responsibility is to have system and system integration knowledge regarding the impact on different signatures.

Optical sign.

IR- sign.

Emitted signals

Acoustic sign.

Magnetic signature

Pressure sign.

Electric sign.

Other sign.

Wake

Radar- signature Air

Underwater

Other sign.

Figure 9.13-4 Ship Signatures

6. The Hsm Installation Impact On Signatures

All of the missions mentioned above have their specific signature requirements. This, in combination with the actual signatures affected by the HSM, gives input to the design. The missions, where HSM are involved will of course have the largest impact on the signature requirements for those particular missions. 6.1 Radar Cross-Section (RCS) The RCS contribution of the HSM installation can mainly be connected to the design of the air inlets and outlets as well as the exhaust outlets. Also the WJU affect the RCS but the effect of this will not be further discussed in this paper. All outlets and inlets are covered with radar screens. The radar screens will be perceived as a flat surface as long as the circumference and depth of the holes in the radar screen are well designed. If no radar screen or a badly designed radar screen were to be used, the radar wave would see a cavity. There is



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always the possibility to use radar-absorbing materials (RAM) but this would create new problems and is therefore excluded in this application. Also the perimeter of the intakes and outlets should be carefully designed to minimize the edge effects.

Air intake Air intake HSM

Figure 9.13-5.

6.2 Infrared Signature (IR)

The contribution of the HSM installation to the IR signature emanates mainly from the air intakes and outlets ducts, exhaust gas ducts and exhaust gas plume. The objects inside the hull, such as the Gas Turbine, will be thermally insulated from any IR sensor due to the hull configuration. It is well known that especially intakes and outlets very quickly adopts to the flowing medias temperature. This means that for air intakes the apparent temperature will be that of the surrounding air thus creating a negative contrast when compared to the hull if the hull’s temperature is higher than the air temperature. To reduce this effect the geometric design and placing of the air intake is very important. The same considerations are made in the case of air outlets. The IR radiation from a heated object such as a conventional funnel can be seen with IR sensors/detectors in almost any viewing aspects. The ”funnel” of the Visby class corvette can with great difficulty be detected due to the placing of the exhaust gas discharge. The discharge of the exhaust gas close to the water surface in combination with the fact that it is almost impossible to see any warm surfaces will give very low IR radiation from this installation. The HSM exhaust gas ducts will be equipped with injection nozzles injecting seawater into the exhaust gas flow. By doing so, the temperature of the exhaust gas will drop dramatically and thus reducing the IR signature. See the exhaust gas duct in the figure below.

A ”wash out” of the exhaust gas will occur due to the injection of seawater, this will reduce the number of particles emitted to the surroundings. The particles generate IR radiation and by reducing both the temperature and number of the particles the IR signature of the exhaust gas plume will be greatly reduced.



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Low Speed Diesel Engine

Main Reduction Gearbox

High Speed Gas Turbine

Exhaust Gas Duct

Figure 9.13-6. Exhaust Gas Duct and Machinery

6. Hydro Acoustic Signature

Vibrations generated by engines, gearboxes etc. are transmitted to the ships-structure and further to the surrounding water and will together with the propulsion unit, generate a hydro acoustical signature. This signature could be measured or observed at different distances by a simple hydrophone or by more complex sonar arrays.

The hydro acoustical signature for Corvette type Visby is divided into both requirements and goals. The goals are more difficult to achieve. The hydro acoustical signature is specified in the Technical Specification as amplitude versus frequency and presented in a diagram, where each curve represents different missions.



361

dB rel 1µPa 1m

1/3 octave band Hz

Goal

Requirement

Figure 9.13-7

Structure borne noise dominates the transmission to the water, but a high level in airborne noise can contribute to the total hydro acoustical level, therefore these two sources are of greatest interest when conducting SEA-calculations. The SEA-calculations giving predicted signature levels were carried out after the different contractors were chosen.

During 1996 MTU performed measurements on airborne- and structure borne noise on a representative engine MTU 2000. These measurement data was provided to KNS and the data was used for SEA-predictions. The hydro acoustic predictions cannot be performed without accurate and relevant data from the sub-contractors. With reference to the hydro acoustical level, which the LSM generates on its double resilient mounts together with an enclosure, maximum vibration levels could be introduced into the Technical Specification for MRG and GT for different conditions. Factory acceptance test (FAT) has today been performed on the first two LSM (MTU 2000) and the measured vibration levels have been compared with the requirements in the Technical Specification and the results are encouraging both in vertical and in transverse direction. Less vibration gives less transmitted vibration to the ships structure and this is very important when vibration (v) in the formula for transmitted energy to the ship’s structure is a function of v². FAT has also been performed on the two first MRG. Unfortunately the manufacturer only could run the gearboxes during factory acceptance as no load test (spin-test). During these circumstances the vibration levels at different speeds are quite below the requirement and at the most relevant frequencies the margins are reassuring. 6.4 Magnetic Signature Scope. To make sure that Visby will have a low magnetic signature (sea mines are often triggered by magnetic sensors!), every piece of equipment onboard is investigated from magnetic point of view. The amount of magnetic material is reduced as far as possible, but for technical or economical reasons equipment can not always be made of non-magnetic material.



362

For the MRG, the ferromagnetic gearwheels are the main magnetic sources. Furthermore, since the wheels are turning in several different speeds, they may all become transducers of magnetic ”radiation” if they are magnetized. The gas turbines are from magnetic point of view rather ”harmless” to the overall signature of the vessel and no changes have been made to alter their design due to magnetic requirements. Ferromagnetic fields. The magnetic field from an object is consisting of two parts, induced and permanent. The induced part is always proportional to, and aligned with, the field surrounding the object. The permanent part is a residual magnetism that acts as a ”magnetic memory”. This part may be several times higher than the induced part and it may have any direction in the object. A process called Deperming where the small magnetic ”cells” in the iron are forced to counteract each other may reduce the permanent magnetization. For the MRG, Cincinnati Gear Company had to build a new Deperming plant since their standard Deperming equipment was not sufficient for fulfilling the FMV requirements. The requirement in this case was a certain maximum ratio between permanent and induced magnetization. As mentioned above, the induced magnetization is dependant of the surrounding earth’s magnetic field. By changing the field around the object with ”electromagnets” it is possible to find a setting where the magnetic field from the object and the field from the coils around will be in balance. Since a ship can move to different locations, in different headings and with different pitch and roll the earth’s magnetic field may ”hit” the object in any angle. For that reason it is necessary to have a three-dimensional coil system on every major object onboard. The current in the coils must furthermore be updated several times per second to keep the best compensation due to ship movements. One MRG, two gas turbines and the auxiliary equipment attached to them are from magnetic point of view seen as one unit. The coil design for each such unit is rather complex due to a lot of practical circumstances. The coil cables must not interfere with hull structure, moving parts, hot parts or service points. On top of that they must be in the best possible ”magnetic” position. Degaussing System. When the MRGs arrive to Sweden they will be brought to a magnetic land range Component Magnetic Measurement (CMG) where the coil system will be tested and tuned. The figure below shows the preliminary design of the degaussing coils for the MRG and the gas turbines. The red, blue and green colored cables can, with the right setting and current, compensate for magnetization in any direction.



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Figure 9.13-8 Preliminary Degaussing System GTPMS



A number of turns in each coil can be set during magnetic ranging. The experiences from the Landsort-class Mine Counter Measurement Vessel (MCMV) shows that a degaussing system, with coils on all major parts, can reduce the magnetic signature considerably, giving the vessel a much better chance to cheat the magnetic sensors in a sea mine.

6.5 Summary The signature management work to reduce the signatures from the HSM is carried out by all contractors in all phases as:

- Project work - Design work - Manufacturing - Installation of components in the ship - Sea Acceptance Test (SAT)

Different ship signature requirements have been transformed to measurable limits for the HSM components. At SAT and forthcoming ship system tests all signatures will be measured to verify and secure the ship requirements. After delivery of the ships to the Navy, the crew carries out signature management and signature work. During the ship life-time (25 years) the signature work is involved in all maintenance- and repair work. All efforts described in this paper, reveal that the Visby class ships HSM will have lower signature levels, than earlier ships in the RSwN. All parties involved have increased their knowledge and in some cases improved equipment and products. Other bonuses are lower exhaust emissions, lower noise levels, etc. and some of the signature work can be a benefit for other military or civilian HSM applications. REFERENCES

1. ASME PAPER No 98-GT-437, “A 21st CENTURY WARSHIP WITH A 21st CENTURY PROPULSION SYSTEM”

2. IMEC 94, Paper 7, “Signature management as an integral part of new warship design”

3. IR signature suppression of Modern Naval Ships, J. Thompsson, D. Vaitekunas



APPENDIX 9.14

PROTECTION AGAINST A NUCLEAR ELECTRO MAGNETIC FIELD (NEMP)



1. General A nuclear explosion at high altitude will cause an electromagnetic field with very high field strength. High altitude here means about 30 km or more above earth surface. This field will furthermore cover very large areas. For instance if a high altitude explosion occurs over central Europe the electromagnetic field will also cover the whole of Sweden. The incident field may have field strength of up to 50 kV/m. The duration is however, short and since the rise time of the pulse is also very short (about 3 nanoseconds) the pulse will have its spectral energy concentrated to frequencies up to about 100 MHz. Equipment that will be subjected to the field will thus be exposed to a high field strength that will induce voltages and current that can cause severe damages unless the equipment is properly protected. The following sections will describe and discuss methods to obtain protection in order to sustain the incoming NEMP. 1.1 Protection Philosophy One protection method hereto is to define different zones and to maintain these as barriers in order to reduce the incoming voltage to levels that can be controlled by normal EMC requirements and methods. An example of this is shown in Figure 9.14-1.

Exterior the ship, with full impact of the NEMP field, is called zone 0. This zone may also include compartments that for different reasons, like open hatches or slots, cannot be considered shielded enough. Examples of such compartments are hatched in Figure 9.14-1. This means that the protection border must be maintained between the hatched areas and the interior. If necessary by attenuation reasons, more zones may be necessary to introduce in order to protect sensitive areas like CIC (=Combat Information Center), radio and apparatus rooms etc. An attenuation of about 40 dB can normally by maintained by a zone border and an aim must be to have an attenuation of at least 50 dB from outside to inside which can mean that at least three zones, including zone 0, are needed. The remaining transient field from an incident field of 50 kV/m can then be handled by normal EMC methods and requirements. This is of course depending upon selected material, openings, slots etc. Methods for maintaining the obtained zones invoke grounding cable shielding and filtering. An exposed cable, which thus can carry a high, induced voltage, must be treated so that the voltage cannot penetrate into the interior of the ship. Using a filter mounted and connected directly to the zone barrier can perform this. The cable shields must furthermore be properly connected to ground at zone barriers. This is especially important at cable ends. The ships grounding systems and the interaction between them and the overall grounding philosophy will not be described in this paper since it has already been handled.1 Not only cables but also metallic pipes, ventilation ducts and similar must be treated in a way that induced voltages are not allowed to penetrate into next zone. These precautions must be made in every zone barrier. 2. Methods and Philosophies

Figure 9.14 -1 Example of EMP zones



2.1 Example 1 The first example shows two units that are mounted in the exterior zone, i.e. they will, together with their cabling, be exposed to the full field strength. The cables from unit 1 are connected to electronically equipment inside the ship, i.e. in zone 1 or higher. The exposed units are supposed to be provided with sufficient shielding, i.e. about 80 dB, marked by the hatched borderline. They are also correctly grounded to the ships grounding system by copper braids with a length to width ratio not more than 5:1. The copper braids must also be connected by at least M8 bolts with spring washer and nut. The field that is induced in the units, to their cabinets, can thus be de -coupled via the ground strap to the ships grounding system. The connected cables must furthermore be shielded. The shield must be connected to the unit 1 and unit 2 grounds by using connector with such back shells that permit a 360o shield connection through the connector and

to the cabinet. Connecting the shield via a connector pin is not permitted. If the cable is taken into to the unit through a cable gland instead of by a connector, as is the case with the cable between unit 1 and unit 2, above, the cable must also be grounded to the cabinet by using grounding insert in the gland that also permits 360o ground connection. Grounding the shield by forming it to a pigtail that is brought into the cabinet and there fastened to an inner grounding screw is not permitted since this method invokes an inductance and an internal antenna that can radiate inside the cabinet. The cable gland may be connected to the cabinet by its threads if the material is thick enough, if not an internal locking nut may be used. Applying these measures means that a protection zone can be maintained from the possible victim unit, Unit X, ins ide the ship, through the cabling and further in to and including the exposed units, 1 and 2, as shown in Figure 9.14-3. The ship bulkhead will form the zone barrier between zone 0 and zone 1. If further attenuation is needed on the way from zone 1 in to the victim unit additional shielding, this can be created by for instance racks, additional cabinets or additional shielded bulkheads. The same principles for cable shield connection must, however, be applied to each zone barrier.

Figure 9.14 -2 Example 1. EMP-protection by zone topology



Then, suppose that one of the units in the exposed zone, 0, is not provided with sufficient shielding effectiveness an other quite common situation will now appear. This will be discussed in the following Section, Example 2. 2.2 Example 2 Example 2 will discuss a quite common situation when one of the outboard, exposed units, here Unit 2, is not provided with sufficient shielding to withstand the incoming field strength, i.e. less than 50 dB. The protection philosophy can now not longer be maintained since the incoming field strength may be induced to unit 2 and then transferred to unit 1 and further via the cables to the possible victim unit, X, inside the ship. This situation is shown in Figure 9.14-4. This situation may however, still be controlled. Under condition that the remaining protected units and zone barriers are treated as described in Example 1, the now dangerous link, formed by Unit 2 and the inter connecting cable to unit 1 can be solved. Implementing a new zone barrier used to isolate the exposed unit 2, from the rest of the system can now do this. A filter inserted in the zone barrier, as shown in Figure 9.14-4, can now be the necessary isolator. This filter must have sufficient attenuation for frequencies up to about 100 MHz to suppress the induced voltages into Unit 2 to values that can be managed by normal EMC means in the system. In addition, the filter capacitance to ground must be kept as small as possible in order minimize the total leakage current that can cause electrolytic galvanic corrosion to metallic parts. It is furthermore important that the filter is correctly mounted and grounded to the zone barrier, i.e. the cabinet of Unit 2, in order to take the de-coupled voltage through the ground strap and to the ships grounding system.

Figure 9.14 -3 Example 1 as topological view



The discussed example can also be seen as a topological view, see Figure 9.14-5.

2.3 Example 3 The used example can be changed further by assuming that both units in zone 0, i.e. unit 1 and unit 2, are not provided with sufficient shielding and thus exposed to the full incoming field strength. This situation is shown in Figure 9.14-6. The previous discussion in example 1 and example 2 can however, still be applied as will be shown in the following.

Figure 9.14-4 Example 2. One unshielded unit in exposed zone

Figure 9.14 -5 Example 2 as topological view



The difference now is that all outboard units, i.e. unit 1 and 2 in the example, are now exposed to the field strength. It must thus be assumed that their internal electronic devices can withstand this treat since this mounting location has been selected. The problem is thus concentrated upon to prevent the induced voltage to affect other, inboard, parts of the system or, for worse, to prevent the induced voltage to be brought into the ship and also affect other systems. This aim can now be achieved by applying the same principles as in example 2, above, meaning that the outboard units, 1 and 2, must be seen as affected. The solution must then be to implement a protection where the effects can enter into the next higher zone. In this example this means that the cables leading from the outboard units into the interior of the ship must be provided with barriers that can prevent the induced voltage from entering the interior. The tool to do this is implementing NEMP-filters to those cables. These filters that must have main characteristics as mentioned in example 2, above, must be mounted close to the zone barrier, preferably to the same inlet panel to which the incoming cables are mounted and grounded. The filters must furthermore be securely grounded to the same panel in order to permit that the de-coupled voltage can be transferred to the ships grounding system. The situation discussed above can also be seen as a topological view in Figure 9.14 -7.

Figure 9.14-6 Example 3. All units in exposed zone are unshielded.

Figure 9.14 -7 Example 3 shown as topological view



3. Conclusion and Guidelines From the discussed examples can be seen that implementing full NEMP protection does not always need filtering of all connection cables. Neither is full shielding of exposed units always needed although such shielding can improve and simplify the overall solution. By analyzing the system and its installation methods and steps that will give sufficient protection can rather easily be determined. Such an analysis can normally be made as follows:

1. Start the analysis by using an installation drawing to determine where the different units and equipment’s are located. A useful tool is to redraw this into a topological view as those used in the earlier used examples.

2. Determine which units and cables that are located in the exposed zone. 3. Determine how many protection zones that can be obtained from the exposed units and cables in

to the units located inside the ship. Estimate the shielding effect of each zone and secure that a total shielding effectiveness of at least 50 dB can be obtained. If the shielding factor is less, additional shielding measures may be necessary.

4. From Item 2, analyse all exposed units to secure that their shielding is sufficient, i.e. they must have a shielding characteristic corresponding to about 50 dB for frequencies up to about 100 MHz. If not they must be regarded as unprotected and thus be subject to additional protection.

5. From Item 2, analyse all exposed cables. If they are fiber optic cables without any internal metallic lead or metallic shield, they can be regarded as protected and no further action is needed. However, if a fiber optical cable also comprise any metallic part or lead it must be regarded as a conventional cable and treated like such. For conventional cables applies that if the exposed length is longer than, say about 0,4 meter the shielding effectiveness may not be sufficient to withs tand the induced voltage. This means that long exposed cables must be provided with additional protection by being routed within metallic conduits.

6. Ensure that all units and cables have sufficient grounding connections. 7. Locate all cables coming from exposed units going inboards and determine if and where filters

are needed. Each zone penetration must be protected. 8. Select filters to be used. This must normally be done together with the manufacturer of the

involved units in order not to degrade the intentional signals as well as together with the shipyard in order to harmonize with other protectional measures.

9. Use filter with as low capacitance to ground as possible. This is essential since the capacitive leakage current from every filter will contribute to create severe currents that can cause problem like electro galvanic corrosion to outboard metal details.

10. Ensure that the selected filters will be correctly mounted with respect to grounding and cable shield connection.



APPENDIX 9.15

DAMMAGE RADII AND FRAGMENT DENSITY REDUCTION



Annex 2 Damage radii and fragment density reduction

Formula for blast damage radius R = c ⋅ 3 He

R has the dimension “meter“. HE is the content of effective high explosive in kg. As a first assumption you may take the real content of HE if there is only a light casing. For a typical casing for a missile you may take 0,75 HE as effective for the blast production (The rest of HE energy is necessary for the fragmentation of the casing). The formula is based of the detonation energy of TNT. For more energetic new sorts of HE you should multiply the HE mass with a factor between 1.1 and 1.2. With the constant “C” you can estimate the damage radius of the blast of a detonation with respect to various types of structures and equipments.

You should interprete R as follows:

a 5 mm bulkhead will be destroyed/severely damaged in a distance from the detonation point of R = 1,9 ⋅ 3 He

light machinery under direct effects of blast will be destroyed in a distance of R = 2.2 ⋅ 3 He

light machinery behind a bulkhead or deck will be destroyed in a structure of R = 1.1 ⋅ 3 He The table “Reduction of Fragment Densities“ is based on calculations for frigate structures, but may be used for smaller ships as well because the plate thicknesses are rather similar. You should read the table as follows: Given 100 % effective fragments (e.g. heavier than 1 g) on the first bulkhead 40% of them will reach the next bulkhead. The other part of them will either be stopped by the first bulkhead or by equipment in the next room or will leave this room by penetrating the adjacent decks or the shell. For the effective fragment density on the first bulkhead or deck of artillery shells or smaller anti ship missiles there are no valid figures available, however it seems reasonable to take as a first assumption 8 fragments per square meter for a bulkhead and 15 fragments per square meter for a deck due to the different distances to the probable detonation point.

Constants „C“ for Blast

C 5 mm bulkhead 1,9 2 x 5 mm double bulkhead 1,2 Light machinery 2,2 Light machinery behind bulkhead/deck

1,1

Electrical/electronic components

2,8

Electrical/electric components behind bulkhead/deck

1,4

4 mm deck 2,5 2decks 4 mm each 1,25 doublebottom 1,5

Reduction of Fragment Densities

WW

eeqquuiippmmeenntt

RR



Onfirst bulkhead

5 mm 100 %

Onsecond bulkhead 5 mm

40 %

On third bulkhead 5 mm

10 %

On first 2 x 5 mm double bulkhead

100 %

Onsecond bulkhead 5 mm

25 %

On first deck 4 mm 100 % On second deck 4 mm 40 % On third deck 4 mm 15 %



APPENDIX 9.16

PROPOSAL FOR THE SRENGTHENING OF DECK STRINGERS



Proposal for the strengthening of deck stringers

Possible executions

• Increased plate – thickness e.g. 10 –12 mm at deckside and hullside and either:

a) box profile, intercostal inner web between web frames b) triangle profile, intercostal inner web between web frames

• One approach of dimensioning the strengthened stringers:

WSD K= 1.3 to 1.5 W SD , depending on the minimum requirement of global structure strength after a hit e.g. to operate the ship in moderate sea states. WSD K= resisting moment, related to the site of the deck with strengthened deck stringer WSD = resisting moment, related to the site of the deck without strengthened deck stringer

a) b)

Approx. 700mm

Approx. 700mm

800mm

800mm