PREPARED BY:

BUOYANT AIRCRAFT SYSTEMS INTERNATIONAL

DATED: SEPTEMBER, 2015

© BUOYANT AIRCRAFT SYSTEMS INTERNATIONAL – ENGINEERING RESEARCH AND DEVELOPMENT DEPARTMENT

A GROUND HANDLING SYSTEM DESIGN THAT FACILITATES

DOCKING OPERATION OF A RIGID TRANSPORT AIRSHIP

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EXECUTIVE SUMMARY

Buoyant Aircraft Systems International (BASI) was founded in 2011, by Dr. Barry E. Prentice,

with Dale George, an award-winning Industrial Designer, to develop a transportation solution to

the high cost of shipping groceries and supplies to Canada‟s remote northern communities and

resource developments. The food insecurity and health problems experienced in the North can

only be solved by reducing transportation costs. BASI‟s goal is to develop a freight

transportation system based on 4th generation airships that can serve remote communities and

resource developments year-round and cut their freight shipping costs in half.

The transport airship system must operate during the cold winter weather of northern

Canada, while handling the logistics cargo transshipment quickly and safely. The MB310

SkyWhale is BASI‟s answer. This airship is rigid, all-metal, water ballast equipped, and hybrid-

electric/hydrogen powered. The conceptual design of the SkyWhale is available in a separate

document. This report considers the ground interface.

The requirements of the ground handling system are to accommodate the air movement

around the airship with enough stability and control to quickly and safely transship cargo

between forklift trucks and the airship cargo bay. Rigid airships are very large structures. When

the wind changes or gusts, the ground handling system must react to counter the instability and

maintain the relative position of the material handling equipment. This report sets out the BASI

AirDock design for safely docking, mooring and transshipping freight to the SkyWhale airship.

This report consists of three major parts. The first part provides an introduction and

background on the state-of-the-art Ground Handling Systems (GHSs) in airship operations. The

second part explores the problems encountered in these systems and establishes requirements and

constraints based on historical GHS designs and the lessons learned from them. A Pin-gear

Driven Heavy-duty Turntable (PDHT) GHS design, called the BASI Airdock, is presented in the

last section. This system complies with all the requirements and constraints discussed in this

report. The Airdock consists of built-in mooring and docking capabilities. It provides a highly

efficient, reliable, flexible, cost effective and safe solution for the transshipment of freight to a

rigid transport airship.

The BASI Airdock is not site specific and can be used at aerodromes all over the world.

This innovation forms a crucial link in the airship transport network. The Airdock GHS can be

customized to meet a plurality of meteorological and infrastructure conditions. The Airdock

prototype will be engineered and developed by BASI in collaboration with Carousel USA. The

estimated cost of engineering and developing this design in ROM is $1-$2 million.

This report does not include any specific technical details pertaining to the engineering

analysis of this system because it is still in its preliminary design phase and awaits further

investment for a successful execution. The economic importance of this innovation is not

discussed in this report but is obvious. The GHS is the missing link of the transport airship

supply chain. The BASI Airdock completes the transportation logistics interface that makes

transshipment possible between trucks and transport airships. Lowering the cost of the GHS

reduces freight costs for shippers and increases profits for airship operators.

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TABLE OF CONTENTS

Executive Summary ............................................................................................................. i

Table of Contents ................................................................................................................ ii

List of Figures .................................................................................................................... iii

1. Introduction and Background ......................................................................................1

1.1. Ground Handling Systems Terminology ............................................................ 2

1.2. Review of Ground Handling Systems................................................................. 2

1.3. State-of-Art Ground Handling Systems .............................................................. 3

1.4. Economic Viability ............................................................................................. 6

2. Design Problem Analysis .............................................................................................6

2.1. Design Motivation .............................................................................................. 6

2.2. Ground handling system requirements ............................................................... 7

2.2.1. Generic Ground Handling Problems .............................................................. 7

2.2.2. Forces on an Airship while Moored ............................................................... 7

2.2.3. Design Requirements Summarized ................................................................ 8

2.3. Design Constraints .............................................................................................. 9

2.4. Design Criteria .................................................................................................... 9

3. Design Solution Analysis ...........................................................................................10

3.1. Turntable Design and Architecture ................................................................... 10

3.2. Turntable Design Features ................................................................................ 13

3.2.1. Built-in Mooring Winch System .................................................................. 13

3.2.2. Pin-Gear Drive System................................................................................. 14

3.2.3. Wheel Assemblies ........................................................................................ 16

3.2.4. Mission Control System ............................................................................... 16

3.2.5. Turntable Assembly Structure ...................................................................... 17

3.3. Turntable Design Capabilities ........................................................................... 18

4. Conclusion .................................................................................................................20

Works Cited ......................................................................................................................... I

Appendix – A1 ...................................................................................................................III

Appendix - A2................................................................................................................... IV

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Appendix – A3 .................................................................................................................... V

Appendix – A4 ................................................................................................................. VII

Appendix – A5 ................................................................................................................ VIII

Appendix – A6 .................................................................................................................. XI

LIST OF FIGURES

Figure 1: Designs of rigid, semi-rigid and non-rigid transport airships [1] ........................ 1

Figure 2: A Good Year blimp attached to a mobile low mast [12]..................................... 4

Figure 3: A schematic of the landing and unloading system employed by Aeros [15] ...... 5

Figure 4: Three dimensional schematic of the landing operation and cargo exchange

using PDHT system .......................................................................................................... 12

Figure 5: A Pin-gear Driven Heavy-duty Turntable (PDHT) design with built-in mooring

system ................................................................................................................................ 13

Figure 6: A Sample mooring winch with wireless remote controls. [10] ......................... 14

Figure 7: Pin-Gear Drive System [9] ................................................................................ 15

Figure 8: Pin-Gear Drive system employed in the GHS [9] ............................................. 15

Figure 9: Wheel assembly used to facilitate smooth rotation of the turntable [9] ............ 16

Figure 10: Mission control system with various operational modes to control the PDHT

[9] ...................................................................................................................................... 17

Figure 11: Two-Dimensional drawing of V-section for the turntable‟s deck as proposed

by Carousel USA [9] ......................................................................................................... 17

Figure 12: Three-Dimensional line drawing of V-segment of the support structure as

proposed by Carousel USA [9] ......................................................................................... 18

Figure 13: Two-Dimensional drawings of the Center bearing assembly as proposed by

carousel USA [9] ............................................................................................................... 18

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1. INTRODUCTION AND BACKGROUND

A fourth generation of airships is being propelled by advances in the fields of materials,

communications, propulsion and computerized control systems. A diverse range of rigid, semi-

rigid and non-rigid transport airships are being proposed and tested all over the world [1]. A

collage of these transport airships is shown in Figure 1.

Figure 1: Designs of rigid, semi-rigid and non-rigid transport airships [1]

Despite these design innovations that seek to create a practicable transport airship, the

biggest impediment yet to overcome is the successful development of Ground Handling

Infrastructure (GHI).

Airship technology has been continuously operated for over 115 years, but not as freight

transportation vehicles. Airship developers continued to invest in technology for advertising

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blimps and small portable mooring masts. However, these masts are not suitable for the transfer

of freight because an airship floating at a mast is too unstable.

This report presents research on Ground Handling Systems (GHSs) that have been used,

issues with current proposals, and the BASI AirDock docking and mooring structure for rigid

airship freight transshipment operations.

1.1. GROUND HANDLING SYSTEMS TERMINOLOGY

A Ground Handling System (GHS) can be defined as “all the actions and procedures

necessary to preserve and maintain an airship while it is in a „moored‟ state and which facilitate

the transitional phases that allow an airship to safely arrive at and depart from this state.” [5].

According to Gabriel Khoury [5], an airship GHS requires about 40 tasks to be completed to

ensure operational safety. Some of these tasks are accomplished by a ground crew and are not

discussed further in this report. Most of these tasks are completed by the GHS in place. This

report focuses on the most important GHS requirements of transport in airship operations:

mooring and docking.

There is a subtle difference between mooring and docking an airship. Mooring consists of

being anchored so as to weather vane rather than staying in a fixed position. This is essential

because of the large profile of the airship, it is necessary to keep it pointed into the wind.

Docking is the landing and being secured in one spot regardless of the wind direction [3]. This

distinction is important and a key to simplifying GHS operations.

1.2. REVIEW OF GROUND HANDLING SYSTEMS

Various techniques and operational procedures have been devised, tried and tested in the

field for large and small passenger airships, but no transport airship GHS has ever been

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developed. The GHS for the US Navy Blimps and the giant Zeppelins employed between 20 and

100 men to hold on to the docking ropes. Such labor intensive landing systems are no longer

considered. Also, cargo operations were but a small byproduct of their passenger or military

service. What has not changed is the physics behind the buoyant technology.

This experience showed that an airship must be docked and moored into the wind, and

the nose must always point in the direction of the wind. It also revealed that airships are very

light and can be subject to pitch and yaw movements when moored on the ground.

A sample comparison between two sequences of procedures that were employed in

improving the GH of the CargoLifter Airship is provided in Appendix-A1. Another comparison

between the GH systems for rigid airships used by different countries is also provided in

Appendix-A2. These are only two of the numerous examples that have been proposed. Several

patented concepts that have been proposed for docking and mooring airships were also studied.

Some of these concepts are explained and presented in Appendix-A3 and can be read for general

interest.

1.3. STATE-OF-ART GROUND HANDLING SYSTEMS

The only airships in service today are small advertising blimps and the semi-rigid

Zeppelin airships. Their GHS usually consists of a mobile mooring mast, or a mooring tower

designed for airship docking operation. The mast or tower contains a fitting on its top that allows

for the bow of the airship to attach its mooring line to the structure [14].

Most non-rigid (blimp) and semi-rigid airships use fixed or mobile masts. These

advertising blimps are relatively small in size and experience low wind and inertial loads. Figure

2 shows a semi-rigid Good Year blimp attached to a mobile low mooring mast.

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Figure 2: A Good Year blimp attached to a mobile low mast [12]

The standard approach to mooring small blimps and semi-rigid advertising airships is not

necessarily safe or practical for transport airships. Simply as a function of displacement, rigid

airships are extremely large, heavy and experience high wind and inertial loads while docking.

Several mast heights were tried by the British and German airships. Generally, the lower

mast was considered superior, but these airships were always operated as if flying at the mast.

Sudden winds could move them around, and in one famous case the US Navy airship „Los

Angeles‟ was pointed vertical at the mast.

Since the beginning of the 21st Century, interest in using large airships for freight

transportation has been increasing. The need for an efficient and reliable GHS has also come to

light. Several ideas have been put forward but none of them have been tested beyond a small

scale. The most popular current approach is to employ modified hovercraft pads. Some of the

companies that are using this technology include Lockheed Martin, HAV, Aeros, and Aerocat. A

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schematic of the Aeros airship‟s unloading system is shown in Figure 3. Designed with a military

application in mind, these transport airships require minimal GHS and operate heavier than air

without ballasting.

Figure 3: A schematic of the landing and unloading system employed by Aeros [15]

An air cushion system is used for take-off and landing purposes. The air cushions are

basically hovercraft-like landing pads that are designed to operate with reverse fans to create a

suction adhesion while cargo rolls on and off a ramp. The transition from flying to landing and

anchoring is unproven. Similarly, how this system releases its grip and turns the airship when the

wind changes is not described.

Notwithstanding these technical issues, the hovercraft system has a number of economic

drawbacks for lighter-than-air transport. First, the air cushion pad, power systems and fuel add

to the weight of the airship which displaces cargo lift. Second, the complexity of this landing

gear adds to the cost of fabrication and maintenance of moving parts. The hovercraft pads are

also subject to wear and replacement. Finally, the system must consume fuel to hold the airship

on the ground, instead of being passively locked down.

The other leading transport airship designs are more or less silent on how they deal with

the ground handling. Ros Aeroships, Airship do Brazil, and DynaLifter offer no explanations on

their GHI. Varialifter envisions a fixed docking system that the airship is winched down to and

anchored.

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1.4. ECONOMIC VIABILITY

The overall cost of an airship development project must consider operating costs as well

as design and fabrication. All the aspects of the project need to be figured in detail at the

beginning, rather than at the end of the project. It is essential that the GHS is designed in

conjunction with the airship [3].

An economic GHS should be designed to yield high operational efficiency and long-term

reliability in plurality of meteorological and infrastructure conditions. It must be capable of

mooring and docking a transport airship quickly and safely. Ideally, it should be able to provide

similar service for variety of airship designs. The ability to serve different types and sizes of

airships would help reduce the average costs and minimize space. However, the latter requires a

careful examination of the constraints and requirements associated with the design of a GHS for

efficient docking operation. These requirements and constraints are explained in detail in the

Design Problem Analysis section.

2. DESIGN PROBLEM ANALYSIS

This section presents the design requirements and constraints for an efficient and

economically viable solution for GHSs to suit BASI‟s MB 310 rigid airship SkyWhale.

2.1. DESIGN MOTIVATION

The proposed GHS design is structurally resilient, flexible, all-weather resistant, and

most importantly cost effective. This design must withstand different types of forces and

moments experienced by the airship during mooring and docking operations. This design is

technologically transferrable/customizable to meet a plurality of meteorological and

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infrastructure conditions. In remote areas of the North, the GHS will need to operate with

permafrost soils.

2.2. GROUND HANDLING SYSTEM REQUIREMENTS

2.2.1. GENERIC GROUND HANDLING PROBLEMS

The most common physical generic GH problems encountered in airship operations are

threefold; (1) Fragile shell (2) Variable buoyancy (3) Wind and Weather [5].

The first challenge is maneuvering the airship to a docking position without damaging the

hull. A second problem is the control of an airship‟s changing buoyancy. A reliable and accurate

means for monitoring of the lift status and physical adjustment of the ballast weight is required.

The third issue is protecting the airship‟s structure from wind and variable weather conditions.

The first two problems are related to the airship‟s structural design and communication

systems and therefore are omitted in this report. The third problem however relates to the GHS

design and is further studied.

2.2.2. FORCES ON AN AIRSHIP WHILE MOORED

During the docking operation, the forces and moments experienced by an airship are

usually caused by the following effects.

(1) Inertial Effects

(2) Steady Wind Effects

(3) Atmospheric Turbulence

The first effect is a consequence of the airship‟s mass undergoing accelerations. Steady

wind conditions can be accounted for in the design of the GHS. Turbulence, however, is random

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and includes discrete wind gusts, and is unpredictable both in frequency and magnitude [5]. All

these effects strongly influence the design of a GHS.

The inertial effects can be controlled by selecting appropriate mooring points on the

airship and the GH mooring system so as to restrict any translation or angular rotation of the

airship. Steady wind effects can be controlled because they can be predicted and accounted for in

designing the GHS. Turbulence effects may require advanced transient Computational Fluid

Dynamic testing on the airship and use of advanced materials with high strength to weight ratios

for the GHS‟s structure.

2.2.3. DESIGN REQUIREMENTS SUMMARIZED

A GHS must be designed to accommodate following aspects encountered in an airship

operation [5].

(1) The turbulence and sheared flow of the natural wind close to the ground in both

intensity and scale.

(2) The aerodynamic forces of drag, lift, moments and so on.

(3) Inertial forces due to acceleration and mass, including the „added‟ mass of the

displaced air.

(4) The elastic forces in mooring ropes and cables, combined with the flexibility and

strength of the airship structure and the mooring system.

(5) The dynamics, stiffness and damping of the impacting bodies (A rigid airship landing

on a GH structure could produce high static and dynamic impact forces)

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2.3. DESIGN CONSTRAINTS

Before getting into the design phase of this report, it is crucial to fully comprehend the

design constraints and assumptions associated with a GHS in an airship operation. These

limitations and assumptions include:

1. A simple GHS design that accommodates easy, quick, gentle and safe docking of a

rigid airship.

2. High factors of safety to avoid any catastrophe due to ground turbulence.

3. Mechanisms to drive this system that are easy to maintain (high wear and tear

resistance).

4. Overall dimensions that minimize the footprint of the airship.

5. Materials that possess high strength-to-weight ratio i.e. lighter materials are more

economic.

6. Ability to operate in all-weather conditions and wind effects.

7. Technologically flexible, user friendly, and mobile.

8. High operational efficiency and reliability with low maintenance costs.

9. Ability of ground handling equipment, e.g. forklift trucks, to access the cargo bay

of the airship with potential for pitch or yaw movements of the airship.

2.4. DESIGN CRITERIA

A successful GHS design must comply with all the above mentioned requirements and

constraints while still being cost effective.

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3. DESIGN SOLUTION ANALYSIS

This section of the report presents the BASI Airdock solution to the GHS design

problem. The Airdock consists of a Pin-gear Driven Heavy-duty Turntable (PDHT) design with

built-in mooring system. This design offers a viable solution to the GHS problems and fulfills all

the GHS requirements and constraints.

3.1. TURNTABLE DESIGN AND ARCHITECTURE

The Airdock is based on an existing turntable that is engineered to rotate tractor-trailers

with GVW of 80 tons. No engineering analysis has been performed and/or presented for the

integration of this system and the transport airship. The BASI Airdock is still in its preliminary

design stage and will be engineered and developed by BASI and Carousel USA to meet the GHS

requirements and constraints.

The rationale for using a turntable for docking and mooring a rigid airship can be

described as follows. A heavy-duty turntable is assembled and fitted within an excavated area

such that the deck of the turntable is only slightly above the ground level (Further information on

site preparation for installation of the turntable, as recommended by Carousel USA, is presented

in Appendix-A4). The turntable is rotated such that it is oriented into the wind with the docking

site positioned directly under the airship. As the airship approaches the ground, the pilot

dispenses a mooring line using the pneumatic controls inside the cockpit. A ground crew

member connects this line (or lines) to a winch that is systematically located close to the landing

platform on the turntable. Meanwhile, the pilot uses aerostatic lift and vectoring thrust to keep

the position the airship nose into the wind, relative to the turntable landing spot. As soon as the

cargo bay is brought to the desired position, and the line(s) secured to the turntable, the airship is

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winched down to the locking position. Hydraulic locks, built within the turntable secure the

frame of the airship firmly to the deck of the turntable. The first step after secure locking is to

load on ballast to ensure that the airship is ready to unload cargo.

In order to ensure safety of the ground crew, the turntable is able to momentarily lock the

deck in position so forklift trucks can drive on and off. Once the forklift is on the deck, any

movement of the airship is always in the same relative position to the forklift. A wireless remote

control and Pin-gear drive interface system is used to rotate the turntable such that the nose of

the airship always points in the direction of the wind so as to avoid wind effects. A rough

conceptual 3-D schematic of the landing operation and cargo exchange using this system is

shown in Figure 4.

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Figure 4: Three dimensional schematic of the landing operation and cargo exchange using PDHT system

Although not discussed at this time, the turntable is designed to transfer ballast, lifting

gas and fuel from the ground to the airship through a central shaft. The turntable also has an

external power supply that can be connected to the airship while on the ground. A CAD model of

this PDHT system was developed using SolidWorks software. A labeled rendering of this CAD

model can be seen in Figure 5. An album comprising of some CAD renderings of this GHS and

the Airship MB 310 concept can also be found at the end of this report.

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Figure 5: A Pin-gear Driven Heavy-duty Turntable (PDHT) design with built-in mooring system

3.2. TURNTABLE DESIGN FEATURES

This section describes some major mechanical and structural features of the GHS design.

These features will be engineered and developed later on by BASI and Carousel USA to meet the

GHS design requirements.

3.2.1. BUILT-IN MOORING WINCH SYSTEM

The mooring winch system shown in Figure 5 consists of a gearmatic winch with a spool

of wire cable and a pneumatic remote control to facilitate mooring operation. A sample12 volt

winch with wireless remote control device is shown in Figure 6.

Ramp Winches for Mooring

Heavy Duty Turntable

Pin-gear Drive Box

Green Xenon lights = Night Visibility Red points = Built-in Hydraulic Locks Centre Bearing Assembly

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Figure 6: A Sample mooring winch with wireless remote controls. [10]

The type of winch and the cable material and dimensions will be chosen such that they

are capable of withstanding the loads from the airship docking operation later on in this project.

3.2.2. PIN-GEAR DRIVE SYSTEM

A Pin-Gear Drive is a special form of fixed axle gear transmission. The large wheel with

cylindrical pin teeth is called pin wheel. It can be divided into outer gearing pin gear

transmission (shown in Figure 7 (1)), inner gearing pin gear transmission (shown in Figure 7

(2)), and the rack gearing pin gear transmission (shown in Figure 7 (3)) [9].

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Figure 7: Pin-Gear Drive System [9]

As the pin wheel is round pin shaped, it has simple structure, easy processing, low cost,

and easy overhaul compared to the general gear. This type of drive system should be sufficient

for our GHS design needs. A picture of a pin-gear drive is shown in Figure 8.

Figure 8: Pin-Gear Drive system employed in the GHS [9]

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3.2.3. WHEEL ASSEMBLIES

The rotational motion of the turntable is facilitated by numerous supporting wheel

assemblies along the circumference that utilize high quality dual bearing assemblies to allow for

frictionless rotation. The bearing assemblies are sometimes also fitted with high strength

polyurethane covering on the turntables as a noise reduction feature. A picture of the wheel

assembly used to support this turntable is shown in Figure 9.

Figure 9: Wheel assembly used to facilitate smooth rotation of the turntable [9]

3.2.4. MISSION CONTROL SYSTEM

The motion of PDHT design shown in Figure 4 can be controlled by a tablet control

system with manual and automatic modes of operation. Other operations such as surveillance and

programing the turntable movements can also be controlled through this system. Carousel USA

has proposed a control system that is capable of all the operational modes mentioned above. A

picture of this system is shown in Figure 10. Further information on this system is provided in

Appendix-A5.

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Figure 10: Mission control system with various operational modes to control the PDHT [9]

3.2.5. TURNTABLE ASSEMBLY STRUCTURE

The top surface of the turntable consists of 8 V-sections that will be fastened together to

form the deck. A two dimensional line drawing of this section from a top view is shown in

Figure 11.

Figure 11: Two-Dimensional drawing of V-section for the turntable’s deck as proposed by Carousel USA [9]

The main support structure comprises 25 – 30 V-segments. Each V-segment is made up

of an assembly of I-beam connections to give high strength-to-weight ratio. Figure 12 shows a

line drawing of this segment.

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Figure 12: Three-Dimensional line drawing of V-segment of the support structure as proposed by Carousel

USA [9]

These V-segments are then attached together to form the skeleton of the turntable. The

turntable and the supporting structure are then fastened together. This turntable assembly is

rotated about a center bearing assembly that consists of a shaft and a thrust bearing assembly for

ease in rotation. Figure 13 shows a general arrangement of the center bearing assembly.

Figure 13: Two-Dimensional drawings of the Center bearing assembly as proposed by carousel USA [9]

3.3. TURNTABLE DESIGN CAPABILITIES

The proposed PDHT design provides easy, quick and safe mooring and docking

capabilities for a rigid airship without any mechanical or structural complexity. A simple pinion-

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gear system with high wear resistance is used to drive this turntable. The turntable in this design

is 80 ft. in diameter because the length of the cargo bay of the rigid airship is assumed to be 60

ft. thus satisfying the size constraint established in the Design Problem Analysis section.

The materials used for the construction of this GHS possess high strength to weight ratios

to account for dynamic and static loads and moments from wind effects and ground turbulence

on the airship. This system is mobile, can easily be transported and assembled on site, and has

easy maintenance owing to its simplicity. Appendix-A6 provides some technical drawings of a

sample turntable assembly, obtained from Carousel USA, for reference purposes. The estimated

cost of developing the turntable in ROM is $450k-$700k. This is a reasonable price compared to

the overall cost of a rigid airship‟s development project.

Based on the above mentioned points, it can be concluded that this design sufficiently

complies with all the GHS requirements and constraints established in the Design Problem

Analysis section and therefore can prove to be an economically viable solution to the GHS

problems.

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4. CONCLUSION

This report provides a description of the Airdock design for GHS. BASI has sought to

find a solution to this problem at an early stage in the development of the rigid airship

„SkyWhale‟. Through an in-depth research, the requirements and constraints for designing an

efficient GHS were established. A PDHT design solution was then presented that meets these

requirements thus proving to be an economically viable solution. As soon as further investment

is procured, a more detailed design will be developed, optimized and analyzed based on

engineering design analysis and will be prototyped and tested for quality and reliability

assurance purposes. The total expected costs for the Airdock assembly, engineering and testing is

$1-$2 million.

I

WORKS CITED

[1] Prentice, Barry E. "Transport Airships for Northern Logistics: Technology for the

21st Century." 1-15, 2015.

[2] Hayward, K. "The Military Utility of Airships", RUSI Whitehall Papers 42, Royal

United Services Institute for Defence Studies, London, 1998.

[3] Gibbens, R. "Airship Support Systems." Lighter Than Air Technology Conference,

1975.

[4] Camplin, G. "Rediscovering the Arcane Science of Ground Handling Large Airships:

An Investigation into Ways of Reducing the Risks Inherent in the Development of a

New Generation of Very Large Airships and of Establishing Guidelines for Their

Ground Handling Procedure." - City Research Online. [Cited August 5, 2015].

[5] I. Khoury, G. A. "Mooring" In Airship Technology, 258-322. Second ed. Vol. 1.

Cambridge: Cambridge University Press, 2004.

[6] Wood, W. (2015). "Mooring tower assembly for a lighter than air vehicle".

5,497,962.

[7] G. Milne, W. (2015). "Docking device for a dirigible". 3,972,493.

[8] Rosendahl, C. (2015). "Method and apparatus for mooring airships". 2,386,814.

[9] Thomson, John. "Lifetime Features.", URL: http://www.carousel-

usa.com/features.php [Cited 02 August 2015].

[10] Northern Tool and Equipment, "Ramsey Patriot Profile 12 Volt Truck Winch with

Wireless Remote 12,000-Lb. Capacity, Model# 109196.", URL:

http://www.northerntool.com/ [Cited 06 August 2015].

[11] Prentice, Barry E. "Airship logistics centres: the 6th mode of transport." Canadian

Transportation Research Forum, URL:

http://aerospacereview.ca/eic/site/060.nsf/vwapj/BarryEPrenticeAirshipLogisticsCentres.

pdf/$FILE/BarryEPrenticeAirshipLogisticsCentres.pdf [Cited 03 August 2015]

[12] "All That's Trucking. Goodyear Picks New Truck Mooring System for Its Blimp.",

URL: http://www.truckinginfo.com/blog/all-thats-trucking/story/2014/09/goodyear-

picks-new-truck-mooring-system-for-its-blimp.aspx [Cited 04 August 2015]

II

[13] Jr., Jim. "Airship U.S.S. Shenandoah, (ZR-1): A Brief History and Scale

Model.",URL: http://jayveejayaresjunk.blogspot.ca/2012/05/airship-uss-shenandoah-zr-

1-brief.html [Cited 04 August 2015]

[14] Wikipedia. "Mooring Mast.", URL: https://en.wikipedia.org/wiki/Mooring_mast

[15] Aeros, "Fuel-Efficient Aeroscraft Airship Prototype Nearing Completion." URL:

http://inhabitat.com/fuel-efficient-aeroscraft-airship-prototype-nearing-

completion/aeros-craft-prototype-complete-12/. [Cited 17 August 2015]

III

APPENDIX – A1

IV

APPENDIX - A2

V

APPENDIX – A3

DESIGN PROPOSALS AND PATENTS FOR DOCKING SYSTEMS

Several patented concepts have been proposed for docking and mooring airships.

Many GHSs have been rejected because they were considered completely impractical and

not worthy of further consideration. The most promising designs were, basically, just

effective developments of techniques used in the past. Most of these designs constituted

some sort of mooring, associated with a high level of automation to facilitate the docking

operation. Essentially, they are labor-saving devices for docking the airship at a mooring

mast. Some of these designs are illustrated in Figure 1a.

Figure 1a: Some of the design proposals and patents for docking systems [6, 7 and 8]

Most of these designs consist of a mobile system based on some form of ground

vehicle or a fairly elaborate fixed mooring installation. The mobile docking systems are

equipped with devices for automatically catching the airship as it flies over them. The

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proposed devices include long prehensile arms, winch-operated cables, and direct-contact

latch arrangement. In order for these systems to work, the airship is required to fly

precisely over the mooring vehicle at a very low relative forward speed hence demanding

superior controllability of the airship. However, these GHSs do not provide pitch control

for the moored airship.

An alternative design that is proposed by R.P. Gibbins is illustrated in Figure 2a.

The idea is to recover the airship as it flies onto a turntable or a mooring ring [5]. The

airship is then lined up by the engagement of a docking probe and secured by a mooring

latch. The docking assembly can then freely rotate with wind conditions. Although this

design was never tested to prove its utility, it did recognize and controls the pitch

movement of a moored airship.

Figure 2a: Automatic Docking System [5]

Although the above mentioned designs could have merits for passenger boarding,

none of them can be adapted to accommodate the docking needs of a rigid transport

airship. They lack structural stiffness, flexibility, controllability, wind load resistance,

and quick and safe freight transferring capabilities.

VII

APPENDIX – A4

VIII

APPENDIX – A5

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X

XI

APPENDIX – A6

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