Mark XI 6B/346

Navigator’s watch issued from November 1949 to the RAF and Fleet Air Arm, later to the Australian, New Zealand and South African air forces and to BOAC. Black dial, centre hacking secondsStop-secondsA time-setting function that stops the running seconds when the crown is pulled, commonly by arresting the balance in a mechanical watch. It allows synchronisation with a reference time signal. Also called hacking seconds; stopping does not itself return the hand to zero., soft-iron inner case and dial against magnetism, screwed crystal ring against decompression. Each watch carries the broad arrow and an issue number with the order year after a slash, e.g. 1064/51; these were stamped by the maker. The RAF ordered from IWC until 1953 and decommissioned the watch in 1981; civilian batches followed in 1973 and the early 1980s.