MANEUVERING OF LARGE TANKERS

This paper presents the results of a series of tests investigating the maneuverability of large tankers which were conducted for Esso International on the steering and maneuvering simulator at the Swedish State Shipbuilding Experimental Tank (SSPA). The simulations were based upon the results of large captive-model tests which were compared with available full-scale trial results to insure the validity of this approach. These tests indicated that the major considerations involved in the maneuvering of large tankers are in many ways different from those affecting smaller ships. As a result, it appears that the applicability of some of the standard maneuvering trials commonly used for smaller ships are of limited value for large tankers. Some revised maneuvering tests for large tankers are suggested. The investigation also indicated the importance of the ship's control system (whether autopilot or helmsman and master) to the maneuverability of large tankers. It was found that the control system has a more significant effect on maneuverability than large changes in dynamic stability or a wide range of ship proportions.