427 Squadron started as a bomber squadron formed at Croft, England on 7 November 1942 and spent its wartime entirely in England as a part of No. 6 Group RCAF, RAF Bomber Command. RCAF’s 25th – eighth Bomber – squadron formed overseas.
427 flew Vickers Wellington Mk IIIs and Mk Xs from its first operational mission on 14 December 1942, a minelaying sortie to the Frisian Islands, until May 1943 when it was relocated to Leeming, North Yorkshire. Re-equipped with Handley Page Halifax Mk V aircraft, the squadron flew intensely until early 1944 when it replaced its inventory with Halifax Mk III aircraft. This fleet saw the greatest number of missions and in slightly more than a year's time they were then replaced by Avro Lancaster bombers prior to the end of World War II. The Lancasters were used for Prisoner of War repatriation until the end of May 1946. 427 was stood down on 1 June 1946.
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