Heading and Track Control Systems (Autopilot)
Heading and track control systems steer a ship automatically to a set heading or along a planned track, under SOLAS V/19 and IMO performance standards.
A heading control system (HCS) steers a ship automatically to a set heading; a track control system (TCS) steers it along a planned track from the electronic chart or integrated navigation system. SOLAS regulation V/19 requires heading or track control on larger ships, and IMO performance standards govern how each holds course, alarms off-heading or off-track, and hands control back to manual steering.
The two systems matter beyond steering. The bridge navigational watch alarm system performance standard MSC.128(75) ties its Automatic mode to the heading or track control system being engaged, a link that MSC.1/Circ.1474 of 23 May 2014 says should not be used on SOLAS ships. The full article will cover the carriage thresholds, the performance standards, the change-over to hand steering, and the alarms these systems raise.