Anchor watch

An anchor watch is the watch kept on a vessel lying at anchor to confirm it is not dragging and to keep the bridge ready to act. The officer of the watch fixes the position on first bringing up, notes the bearing and distance to fixed objects, and sets a swinging circle equal to the ship’s length plus the deployed scope. Position is then checked at set intervals by visual bearings, radar range, and GPS anchor-watch alarm. STCW Code A-VIII/2 part 5 lists the master’s standing duties at anchor: ensure an effective watch, check position and weather, ready the main engine, and stand by to weigh if the holding fails. Dragging shows as the fix walking outside the swinging circle.