And Rescue Transponders
(SARTs) are mandatory carriage safety devices
that form part of the
Maritime Distress And Safety System
(GMDSS). SARTs are
transponders, and operate exclusively in the 'X-band' part of the radio
spectrum, receiving and transmitting at nominally 9,200 MHz to 9,500 MHz.
They are deployed during maritime emergencies as an aid to rapidly locating survivors who may be adrift in a life raft.
Many studies have shown that rescue time is absolutely critical in minimising
loss of life after abandoning ship. The conditions aboard a liferaft can be
unpleasant and disorienting!
Once activated, a SART
‘listens’ for an incoming radar signal from a passing vessel – note that
this can be from ANY vessel or aircraft equipped with a standard X-band radar set, and is
not restricted to specific Search & Rescue craft.
the SART receives a valid signal, it switches into Transmit mode, and responds
to each valid signal by transmitting
a series of twelve (12) sweeps through the band 9,200 to 9,500 MHz, each
transmission lasting just
over 100 microseconds in total. This signal is seen on the passing vessel’s or
aircraft's radar screen as a line of twelve dots, with the SART position being given by the
closest dot. This is a clear, unmistakable, Internationally
and shows the presence AND location of a vessel, survivor or life raft
with an active SART.