AIS dynamic data works by broadcasting vessel movement details via separate position reports. Most fields update automatically from connected ship sensors, but navigational status is entered manually by the officer of the watch.
Dynamic information includes position with accuracy and integrity indications, UTC position timestamp, course over ground, speed over ground, heading, rate of turn where available, and navigational status. Dynamic position reports and static or voyage reports are separate AIS messages. The USCG identifies Messages 1, 2, and 3 as Class A position reports, Message 18 as a Class B position report, and Message 5 as Class A static and voyage-related data.
Dynamic reporting intervals vary with equipment class and the ship's movement or course-changing state. There is no single reporting interval for every AIS unit.
