The 3ft x (61 x 1.26m) flag is of the usual form with the Union Jack to the corner and the RAF roundel to centre. The seam is stamped with Air Ministry markings, dated 1940 and noted as being from RAF Tangmere – an airfield famous for its role in the Battle of Britain.
The base, severely damaged by the Luftwaffe on August 16, was heavily involved in the 1940 battle. Aces Wing Commander Douglas Bader and an inexperienced Johnnie Johnson were stationed there in 1941.
Andy Stowe of East Bristol said: “This came from a private collector who had sourced a number of RAF-related items in the 1970s from a gentleman connected with the airbase, although this was the only item actually labelled with its location.”
Estimated at £300-500 at the auction on May 22, it sold at £1700.
Another notable Second World War flag offered in this sale sold for £4000, eight times the top estimate. The US Navy flag came from USS LCI (L) 94 – a Beach Landing Craft used during the 1944 Normandy landings.