Evaluation of Tug Escort Schemes Using Simulation of Drifting Tankers

Abstract

The ability of tug escort vessels to save oil-laden tankers that become disabled in Prince William Sound, Alaska, is tested using a simulation of the drift path of the tankers. Tug escort schemes are intended to save tankers that have lost steering or propulsion by attaching a line and either holding the tanker from running aground until a repair can be made or towing the tanker to port. The ability of an escort tug to save disabled tankers depends on its position at the time of the accident; the location, speed, and direction of the tanker at the time of the failure; and the wind and current conditions that changed dynamically during a save attempt. To accurately test the save capability of a proposed escort scheme, a simulation of Prince William Sound is created that models dynamic changes in environmental conditions and thus the movement of the tanker.