Main Components of the System

The pick-up gear should be of a suitable type of buoyant line for the task. It should be connected to a marker buoy for ease of identification by the rescuing vessel. Some manufacturers use only one buoy on the pick-up rope, while others use two, claiming that it is much easier to get a rope between two buoys than the buoy itself. The buoys should be fitted with light to facilitate detection at night.

The towing pennant should have a length of at least twice the lightest seagoing freeboard plus 50m from the point it enters the fairlead from the water. This ensures sufficient line to effect the tow and maintain a safe separation from the stricken tanker for fire and pollution safety. The pennant should be fitted with a suitable towing connection at the end to be secured to the towing vessel. This must be a hard-eye splice allowing for connection to a bow shackle.

Many types of chafing gear can be used. Fairleads and ropes can have chafing pieces attached to stop contact rubbing, which will be in place on the vessel. Chafing chains may also be used and will be integrated into the system. If a chain is used, it should be a stud link chain and placed so that the towing pennant remains a minimum of 3 metres outside the fairlead at all times. The fairlead used for the emergency towing system should be sufficient to allow the largest lines to pass through unobstructed. It should give adequate support for the towing pennant during towing operation, which means bending 90° to port and starboard and 30° vertically downwards. The bending ratio (towing pennant bearing surface diameter to towing pennant diameter) should be not less than 7 to 1. The fairlead should be located as close as possible to the deck and, in any case, in such a position that if a chafing chain is used, it is approximately parallel to the deck when it is under strain between the strongpoint and the fairlead.

The inboard end fastening should be a stopper or bracket or another fitting of equivalent strength. The strong point can be designed to be integral to the fair lead. Where a windlass is used as the strong point, it should be constructed to give warning of undue strains by stalling well below the designed maximum safe working load of the weakest element in the system. It should also be correctly sighted to minimize the need for complex line placement and utilize a dedicated fair lead for the emergency towing lines.