empa harbour towage and pilotage

EUROPEAN TUGOWNERS ASSOCIATION

&

EUROPEAN MARITIME PILOTS’ ASSOCIATION

EUROPEAN TUGOWNERS ASSOCIATION E M P A v z w Boulevard de la Woluwelaan 60 Italiëlei 74

B-1200 Brussels B-2000 Antwerp Belgium Belgium

www.eurotugowners.com www.empa-pilots.org

BEST PRACTICE / SAFETY in Harbour Towage and Pilota ge

Recently a working group consisting of EMPA (European Maritime Pilots Association) and ETA (European Tugowners Association) representatives was established. The target of this working group is to define “Best Practice” for both pilotage and harbour towage services and operations in view of the ever growing ships’ and tugboat-sizes. The working group‘s intention is to distribute this position paper to the Associations (and Members) of ship-owners, shipyards, naval architects, engine manufacturers, classification societies, marine surveyors and others to raise awareness of safety issues which were identified as follows:

1. high bollard pull of tugboats vs. strengths of s hips' bollards and fairleads

2. position of ships’ bollards, fairleads and winch es

3. possible strength-problems of ships’ “Push Point s”

4. high minimum speeds of ships

On the following pages EMPA / ETA are describing their concerns and are making suggestions of remedy.


&





1. High Bollard Pull of tugboats vs. strengths of s hips’ Bollards and Fairleads The Problem: With the enormous growth of ships’ sizes over the last years, the towage industry was forced to deploy different tugboats with strongly increased bollard pulls. EMPA- and ETA-members have frequently experienced that often designs of bollards and fairleads on all kinds of vessels are not in step with safety requirements. There have been cases were bollards and fairleads have been torn away, especially when tugboats have to work in the ‘indirect towing mode’. In the "Requirements concerning MOORING, ANCHORING and TOW ING" (1) of classification societies organized in IACS (International Association of Classification Societies), hereafter the “Requirements” , no particular reference is made to the towage sector itself - towage requirements are included in the mooring requirements. The “ Requirements” are focussing on wind forces and currents as well as on drag forces. If bollards, fairleads and winches of ships can withstand these calculated forces then these are considered suitable for 'normal' towing, i.e. harbour towage. The rules differentiate though between “normal towing” and “escort towing”. EMPA / ETA wish to point out that the difference between these two “towing modes” is enormous. When a tug operates at the stern of a ship in ‘indirect mode’, towing forces can be up to 5 times higher than the static bollard pull of the tug. This has to be taken into account when designing ships’ equipment. The “Requirements” have provisions for emergency towing procedures on the bow only (except for tankers). EMPA / ETA are aware that IMO’s Maritime Safety Committee published “Guidelines for Owners/Operators on preparing Emergency Towing Proc edures” (SOLAS II-1/3-4 / Circular 1255 dated 27th May 2008), but these “Guidelines” do only refer to emergencies. However, with this position paper EMPA / ETA are focussing on the daily harbour towage operations for which certain elements of these “Guidelines” such as the “Towing and Mooring Arrangement Plan” for fore- and aft-decks, identifying fairleads, bollards and capacities of the “Strong Points” would be very useful for harbour operations.

Our suggestions: • ships’ crews, pilots and tug-masters must repeatedly be made aware of such possible

forces and the inherent dangers • ships’ operators, naval architects, shipyards, classification societies, marine surveyors

as well as equipment providers must be made aware of these forces and include these considerations in their planning

• the “Requirements” are to be more specific on such towing aspects and here in

particular in respect to container ships • ships’ crews and pilots should be facilitated to have the “Towing and Mooring

Arrangement Plan” at hand, summarizing on-board equipment and SWL’s also for daily harbour towage operations

(1) On the web: http://www.iacs.org.uk/document/public/Publications/Unified_requirements/PDF/UR_A_pdf148.PDF


&





2. Position of ships’ bollards, fairleads and winch es

The Problem: Bollards, fairleads and winches on board vessels are often not optimally placed for connecting tugboats and for different tugboat manoeuvres. The positions of winches sometimes make it difficult for the ships’ crews to safely handle heavy towing gear. Bollards and fairleads are often too far apart with the consequence that the towing gear might be damaged. Towing and Mooring Arrangement Plans are issued by Classification Societies helping Masters and Pilots to be aware of the acceptable loads of these relevant parts for towing and mooring on board the ship. Since about 10 years the rules require marking of bollards, fairleads and winches with the SWL (Safe Working Load) limits. Amongst IACS members different opinions prevail whether the safety margins should be 1.25 or 1.5 times the actual towing forces. A very practical problem is that SWL’s mentioned in ships’ plans are expressed technically correct in Kilo Newton (kN) whereas ships’ equipment is commonly marked in Metric Tons (MT), which, however, is only 10 % of the kN figure (e.g. 230 kN = 23 mt). These differences can easily lead to serious misunderstandings as to equipments’ capacity. As far as we understood, classification societies do not check the “Towing and Mooring Arrangement Plans” upon practicability, for example whether ships have Centreline Fairleads, distances between fairleads and bollards, whether sufficient winch capacity is available to heave up the heaving towing gear etc. Our suggestions: • “Towing and Mooring Arrangement Plans” are to be designed for good and safe seamanship • Ships’ crews and pilots should be facilitated to have the “Towing and Mooring

Arrangement Plans” at hand, summarizing on-board equipment and SWL’s also for daily harbour towage operations. Limitations need to be communicated to the tug-masters.

• Specific needs for harbour-towage (not only emergency-towing) to be recognized and considered for ships’ designs


&





3. Push Points

The Problem Push points on ships' hulls are located on transverse bulkheads or web frames to avoid damages to the shell plating. None of these Push Points is marked with any max SWLs. Are the acceptable pressures of these Push Points known? Will they stand the force of a 70 tbp tug pushing with full power on less than 1 m² plate/hull area? As far as we understood, such calculations are only available for the impact on shore fenders. Often no information is available whether it is acceptable to let tugs push on the transom stern of the ship. Our suggestions: • Push Points to be clearly marked with SWL’s • On-board information to be readily available whether tugs pushing at the transom stern is

acceptable • Already in the design phase, these criteria should be considered

4. High minimum speeds

The Problem The latest generation of large container vessels have an enormous main engine output. Engine manufacturers and ship operators as well as many other actors in the maritime chain have focussed on economic fuel consumption, taking advantage of the ever increasing economies of scale and on the ever increasing sizes of ships. However, the downside is that ‘Dead Slow’ of these large vessels is usually in excess of 6-11 knots through the water. Making fast a tug for a harbour towage at this speed - especially on the ship’s bow - is simply dangerous. The maximum speed of a tug is approximately 11 to 12 knots. Once safely connected, high passage speeds are reducing tugs’ abilities. Beyond 8 kn, tug’s capabilities are very limited and on top it is getting very dangerous for tug and crew.

Our suggestion: • Engines to be designed for 3-6 knots at ‘Dead Slow’ for safe harbour work of tugs and

tugs’ crews.


&





OCIMF Mooring Equipment Guidelines The 3rd edition of the "Oil Company International Marine Forum" (OCIMF) guideline, published in 2008, contains very useful remarks in respect of our above concerns such as: • Limitations on the use of tugs • Requirements for Emergency Towing and Escorting • Requirements on fairleads’ bending diameters, abrasion of tow lines • and many more Unfortunately these guidelines are explicitly issued for tankers only and not for container ships, car carriers or any other ships’ types. Summary: � The European Tugowners Association (ETA) jointly with the European Maritime Pilots

Association (EMPA) wish to raise awareness of the actors in the shipping industry in respect to the aforementioned technical and regulatory concerns in order to improve safety and “Best Practice” for the towage industry when assisting ships in ports.

� In our view the major parties in this maritime environment are

o Shipowners and Operators o Shipyards o Classification Societies o Flagstate Administrations o Naval Architects o Engine Manufacturers o Maritime Surveyors

Comments are welcome to the joint E-Mail-Address [email protected]

empa harbour towage and pilotage

Documents