SEARCH AND RESCUE RADAR TRANSPONDER (SART)
The SART transmits a signal over a swept band in the 9 GHz range (X Band) which appears as a straight line of 'blips' on the radar screen.
Operation SARTs may be packed in a life raft, incorporated in a float-free EPIRB or mounted in a float-free housing egoabove a ship's bridge. The SART may be switched on manually or automatically if immersed in water (eg. when incorporated in a VHF DSC EPIRB) . After switch-on the SART will remain in standby mode (for up to 96 hours) until a radar transmi ssion in the 9 GHz range, from ship or aircraft , triggers a respon se.When this occurs, transmission from the SART appears as a perfectly straight line of twelve 'blips ' (radiating outward from the SART position) on the radar screen. Distance between the 'blips' is 0.6 nm. As a searching vessel draws closer to the SART position the blips will increase in size to form arcs and then complete circles, when the vessel is close enough to trigger the SART transmission continually. The appearance of arcs or circles on the radar screen should serve as a warning to SLOW DOWN! This distinctive signal will be an obvious indication to Search And Rescue craft. When transmitting the SART also 'rings' thereby indicating to the survivors that searchers are close.