Hirth HM 504

Hirth HM 504
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. The Hitachi Hatsukaze Model 11 was a Japanese licensed version.

Data from Katz.

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