AIS Class A

The full-feature AIS transponder mandated for SOLAS vessels, broadcasting on a 12.5 W SOTDMA scheme. SOLAS Chapter V Regulation 19.2.4 requires Class A AIS on all ships of 300 GT and above on international voyages, cargo ships of 500 GT and above not on international voyages, and all passenger ships. It transmits MMSI, position, course over ground, speed, heading, and rate of turn at intervals from 2 to 10 seconds when underway, plus static and voyage data every 6 minutes.