No. 517 Squadron RAF was a meteorological squadron of the Royal Air Force during the Second World War.
No. 517 Squadron was formed on 11 August 1943 at RAF St Eval, Cornwall, when 1404 Meteorological Flight was re-numbered. It was equipped with Lockheed Hudsons and Handley Page Hampdens, which it flew daily out into the Atlantic to collect meteorological data. Between September and November 1943 four United States Army Air Forces Flying Fortresses were temporary attached to the squadron, awaiting the arrival of adapted Handley Page Halifaxes. By November 1943 the squadron had re-equipped with the Halifax and then moved to RAF St David's in Wales. Two further moves followed, one to RAF Brawdy in February 1944 and then after the war to RAF Chivenor where the squadron was disbanded on 21 June 1946.
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