Based loosely on the Supermarine S.6 of the 1929 Schneider Trophy race,
      the prototype Spitfire Mk I first flew in 1936.  Mass
      production was slow to gain momentum and the first Spitfire didn't reach
      squadron service until 1938.
      Although the Spitfire served throughout World War II, its most famous
      contribution to the war was the defense of the UK during the Battle of
      Britain 1940 - 1941.  Vectored to incoming German bomber formations
      by radar, Spitfires and  Hawker Hurricanes kept the Luftwaffe from
      establishing air superiority over England and forced Germany to cancel its
      planned invasion of Great Britain.
      Over 20,000 Spitfires and 2,000 Seafire naval fighters were
      produced.