The Naval Oceanographic Office's first operational use of trawl-resistant packages housing acoustic Doppler current profilers

Two trawl-resistant packages were procured to make current measurements in heavily fished areas less than 200 meters deep. The packages were designed to house RD Instruments' 150-kHz self-contained narrow-band acoustic Doppler current profilers (ADCPs), utilizing 90 degree adapters. With minor modifications, higher frequency ADCPs were mounted in the packages to acquire measurements in the Yellow Sea during the November 1993 to February 1994 timeframe. Pre-deployment and post-deployment modifications, tests, deployment and retrieval problems, and recommendations are discussed.