A SART is a portable radar transponder carried in lifeboats and liferafts, activated during an actual emergency to help searching vessels and aircraft locate survivors using radar rather than visual sighting alone.
How It Works
When a nearby vessel’s radar signal reaches an activated SART, the SART responds with a signal that appears as a distinctive line of dots on the searching vessel’s radar screen, radiating outward from the SART’s exact position — clearly distinguishable from normal radar returns and immediately recognizable to a trained watchkeeper.
Why It Matters
Locating a small liferaft or lifeboat visually, especially at night or in rough seas, is extremely difficult even when searchers know the approximate area. SART dramatically increases detection range and precision, guiding rescue craft directly to survivors.
AIS-SART
A newer variant, AIS-SART, transmits its position via AIS rather than radar response, showing up directly on AIS-equipped vessels’ displays with a clear distress indication — increasingly common alongside or instead of traditional radar SART.
When to Activate
SART should only be activated during a genuine emergency requiring search and rescue — not tested indiscriminately, since activation triggers a real distress response from any vessel whose radar detects it.
Exam Relevance
SART operation and its role in search and rescue procedures are core GMDSS and safety equipment topics in deck officer competency exams.