Founding In February 1940 the Air Ministry constructed an aerodrome on the site of Chivenor farm near a civilian airfield. RAF Chivenor opened on 25 October 1940 within No. 17 Group, Coastal Command. There were two units based there initially, No. 3 (Coastal) Operational Training Unit RAF and No. 252 Squadron RAF, both operating Bristol Beaufighters, Bristol Blenheims and Bristol Beauforts. 1942—1945 From 1942 onward the role of Chivenor was changed from training to anti-submarine patrolling. From 1942 to 1943 the squadron flew the Armstrong Whitworth Whitley, then in 1943 the Chivenor squadron converted to the Vickers Wellington equipped with the ASV radar and Leigh lights. November 1941 to September 1943 No. 51 Squadron RAF: (51 Sqn) Whitleys No. 77 Squadron RAF: (77 Sqn) Whitleys / Wellingtons No. 502 (Ulster) Squadron RAF: (502 Sqn) Whitleys / Wellingtons No. 1417 (Leigh Light Trials) Flight: (1417 Flt) Wellington Leigh light training and development unit July 1942 to September 1943 No. 235 Squadron RAF: (235 Sqn) Beaufighters No. 236 Squadron RAF: (236 Sqn) Beaufighters No. 248 Squadron RAF: (248 Sqn) Beaufighters September 1943 to the end of the war No. 172 Squadron RAF: (172 Sqn) Wellingtons No. 407 (Demon) Squadron RCAF: (407 Sqn) Wellingtons No. 612 (County of Aberdeen) Squadron RAuxAF: (612 Sqn) Wellingtons No. 304 Polish Bomber Squadron: (304 Sqn) Wellingtons Plan for post war 1945 No. 14 Squadron RAF (14 Sqn) No. 36 Squadron RAF (36 Sqn) In November 1941 the structure of the base changed with three new squadrons 51, 77 and 502 flying a mixture of Whitleys and Wellingtons, and one new flight, 1417, that was used to training crews on the Leigh light and radar Wellingtons. In July 1942 three squadrons of Beaufighter were located at Chivenor to offer long range protection in the Bay of Biscay. By September 1943 all of the Whitleys had been taken out of active service at Chivenor, and four squadrons of Wellingtons, 172, 407, 612 and 304, were located at the base. No 172 was the Wellington Training Squadron, taking over from 1417 Flight. The base had personnel from Canada, Poland and the UK. The Plan for the post war, was for Chivenor to become a full-time anti-submarine wing with two squadron's 14 and 36 Squadron. 1946—1949 After the Second World War ended, the future of the station was not certain. In 1946 a group of miscellaneous meteorological and anti-aircraft units moved