de Havilland Gipsy Minor

The de Havilland Gipsy Minor or Gipsy Junior was a British four-cylinder, air-cooled, inline engine used primarily in the de Havilland Moth Minor monoplane, both products being developed in the late 1930s.

The engine was a simplified and smaller version of the earlier de Havilland Gipsy. It featured only one magneto where dual ignition was normal for the Gipsy series of engines. A total of 171 engines were produced, including 100 built in Australia, production moving to that country due to the start of the Second World War.

General characteristics

  • Type: 4-cylinder air-cooled inverted inline piston aircraft engine
  • Bore: 4.016 in (102 mm)
  • Stroke: 4.528 in (115 mm)
  • Displacement: 229.29 in³ (3.759 L)
  • Dry weight: 216 lb (98 kg)


  • Power output: 90 hp at 2,600 rpm
  • Compression ratio: 6:1
  • Power-to-weight ratio: 0.41 hp/lb


  • Valvetrain: Overhead valve
  • Fuel type: Minimum 70 octane petrol
  • Oil system: Dry sump, gear-type pump
  • Cooling system: Air-cooled