This International Standard specifies the structure, performance, inspection and testing of heading control systems to be installed on board ships. It applies to the heading control systems which enable a ship to keep a preset heading with minimum operation of the ship's steering gear, within limits related to the ship's manoeuvrability in conjunction with their sources of heading information. The heading control system may work together with a track control system adjusting its heading for drift. A turn rate control or a turning-radius control for performing turns may be provided. NOTE All the text in this International Standard identical to that in IMO Resolutions [Resolution A.342(IX) as amended by resolution MSC.64(67), Annex 3 and Resolution A.694(17)] is printed in italics.