103 squadron formed in September 1917 as a day bomber squadron and operated on the Western Front. It disbanded in 1919. Reformed in 1936, at the start of the Second World War was equipped with Fairey Battles. In October 1940 it re-equipped with Wellingtons. In July 1942 these were replaced by Halifaxs, and a few months later, these inturn were replaced by Lancasters. It disbanded in 1945. It was reformed in 1954 flying Canberras, but in 1959 became a helicopter squadron flying Sycamores first then Whirlwind and Wessex before disbanding in 1975.