Radar SART

A Radar Search and Rescue Transponder (Radar SART) is a portable survival-craft device that operates in the 9 GHz (X-band, 3 cm) radar frequency band. When interrogated by an approaching vessel's or aircraft's 9 GHz radar transmission, the SART responds by sweeping across the radar band and producing a distinctive pattern of twelve equally spaced dots extending from the transponder's position towards the edge of the radar plan position indicator (PPI). As the rescuing vessel closes to within approximately 1 nautical mile, the dots expand into arcs and eventually into concentric circles, indicating very close proximity. Radar SARTs are required by SOLAS Chapter III on survival craft and rescue boats. Under SOLAS III, Regulation 6, at least one SART must be carried on each survival craft on passenger ships and certain cargo ships, and at least two SARTs must be carried on vessels of 500 GT and above. IMO Performance Standards for Radar SARTs are contained in IMO Resolution A.802(19). The Radar SART operates passively in standby mode with a battery life of at least 96 hours and an active transmission life of at least 8 hours when interrogated. It is distinct from the AIS-SART, which broadcasts AIS position reports rather than responding to radar.