ARCO TANKER SLAMMING STUDY

ARCO Marine currently operates ten tankers which move crude oil from V aldez, Alaska to West Coast ports of the United States. These tankers range in size from 70 000 to 265 000 dwt and operate throughout the ye ar in the harsh environment of the North Pacific Ocean. Some of these ships have experienced bow structural damage, presumably due to slammi ng in heavy weather conditions. In late 1990 ARCO initiated a program with Arctec Offshore Inc. and Ocean Systems Inc. to investigate slammi ng of ARCO tankers. This ongoing effort focuses on three issues: the f requency of occurrence and intensity of impacts; the relationship betw een the impact characteristics, sea conditions, and ship motions; and the development of an onboard slam monitoring and warning system. Duri ng the winter of 1991 data were collected aboard two ARCO 190 000 dwt San Diego Class tankers. This paper describes the data acquisition pro gram, including the problems encountered, the preliminary interpretati on of the collected data, and plans for continuation of the program.