The de Havilland Gipsy Major or Gipsy IIIA is a four-cylinder, air-cooled, inverted inline engine used in a variety of light aircraft produced in the 1930s, including the famous Tiger Moth biplane. Many Gipsy Major engines still power vintage aircraft types.

The de Havilland DH.82 Tiger Moth is a 1930s British biplane designed by Geoffrey de Havilland and built by the de Havilland Aircraft Company. It was operated by the Royal Air Force (RAF) and other operators as a primary trainer aircraft. In addition to the type's principal use for ab initio training, the Second World War had RAF Tiger Moths operating in other capacities, including maritime surveillance and defensive anti-invasion preparations; some aircraft were even outfitted to function as armed light bombers.