Hirth HM 504

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Hirth HM 504
Aircraft engine at Flugausstellung Hermeskeil, pic1.JPG
Hirth HM 504 on display at the Flugausstellung Hermeskeil
Type Inline piston engine
National origin Germany
Manufacturer Hirth-Motoren GmbH, Stuttgart-Zuffenhausen
Major applications Bücker Bü 131
Developed from Hirth HM 60
Developed into Hirth HM 500

The Hirth HM 504 is a four-cylinder air-cooled inverted inline engine. The 504 was a popular engine for light aircraft of the 1930s-1940s and it was used to power a number of Germany's trainer aircraft of World War II. The engine featured a cast magnesium alloy crankcase.[1] The Hitachi Hatsukaze Model 11 was a Japanese licensed version.


Specifications (HM 504 A-2)[edit]

Data from Katz.[2]

General characteristics

  • Type: 4-cylinder air-cooled inverted inline
  • Bore: 105 mm
  • Stroke: 115 mm
  • Displacement: 3,998 cm3
  • Length: 945 mm
  • Width: 520 mm
  • Height: 780 mm
  • Dry weight: 107 kg


  • Valvetrain: 1 inlet and 1 exhaust valve per cylinder
  • Cooling system: air


See also[edit]

Related development
Comparable engines
Related lists



  1. ^ Gunston 1989, p.77.
  2. ^ Dr Ing Hans Katz, Der Flugmotor, Bauteile und Baumuster, Matthiesen Berlin 1940


  • Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9

External links[edit]