Survival-craft device that broadcasts AIS Class A position reports when activated, with an MMSI beginning 970, enabling rescuers to plot its position on AIS displays.
Quick facts
Regulation
SOLAS Chapter III
Frequency
161.975 MHz
In practice
All AIS-SARTs are allocated MMSIs beginning with the prefix 970, as defined in ITU-R Recommendation M.1371, enabling AIS displays to flag the target as a distress beacon rather than a navigating vessel. The device transmits at a power level lower than a standard Class A transponder but sufficient for detection at several nautical miles in typical conditions.
Regulatory detail & full definition
An AIS Search and Rescue Transmitter (AIS-SART) is a self-contained, float-free survival device that, when activated, transmits AIS Class A compatible position reports on AIS channels 87B (161.975 MHz) and 88B (162.025 MHz). The device incorporates an internal GNSS receiver to determine its position and transmits this information at one-second intervals, allowing any vessel or SAR aircraft equipped with an AIS receiver to plot the survivor's location on an ECDIS, chart plotter, or AIS display.
All AIS-SARTs are allocated MMSIs beginning with the prefix 970, as defined in ITU-R Recommendation M.1371, enabling AIS displays to flag the target as a distress beacon rather than a navigating vessel. The device transmits at a power level lower than a standard Class A transponder but sufficient for detection at several nautical miles in typical conditions.
IMO Performance Standards for AIS-SARTs are set out in IMO Resolution MSC.246(83). Whilst AIS-SARTs may be accepted as an alternative to Radar SARTs under SOLAS Chapter III, their use depends on the receiving capability of vessels in the area; Radar SARTs remain valuable where AIS watch-keeping may be incomplete. Battery endurance requirements are not less than 96 hours standby followed by 8 hours continuous transmission.