ANALYSIS OF U.S. COAST GUARD HU-25A VISUAL AND RADAR DETECTION PERFORMANCE

During February 1983, the U.S. Coast Guard R&D Center conducted an experiment in Fort Pierce, FL, to evaluate the visual and Forward- Looking Airborne Radar (FLAR) detection performance of a new Coast Guard medium-range surveillance aircraft, the HU-25A. Visual searches were conducted for small (13- to 18-foot) boats, orange- canopied life rafts (4- to 6-man), and simulated Persons in the Water (PIWs). FLAR searches were conducted for small boats with and without radar reflectors and for the canopied life rafts. Target and aircraft positions were monitored with a computer-based microwave tracking system for detection/miss range reconstruction accurate to better than 0.1 nautical mile. The HU-25A was found to perform better as a visual search platform than other Coast Guard fixed-wing aircraft tested previously. Search speeds between 180 and 240 knots resulted in essentially uniform visual detection performance. The AN/APS-127 FLAR achieved cumulative detection probabilities between 11 and 50 percent in 1.5- to 4.5-foot seas and winds of 6 to 19 knots. Under these conditions, the FLAR system achieved initial detection ranges between 1.1 and 3.2 nautical miles.