TheHirth HM 506 was a six-cylinder air-cooled inverted inline engine that was developed from the earlier four-cylinder HM 504.[1] The HM 506 was a popular engine for light aircraft of the 1930s to 1940s and powered theBücker Bü 133A model trainer. The engine featured a cast magnesium alloy crankcase.
^Gunston, Bill (1989).World Encyclopaedia of Aero Engines (2nd ed.). Cambridge, England: Patrick Stephens Limited. p. 77.ISBN978-1-85260-163-8.
^Grey, C.G. (1972).Jane's All the World's Aircraft 1938. London: David & Charles. pp. 60d–61d.ISBN0-7153-5734-4.
^Schneider, Helmut (Dipl.Ing.) (1944).Flugzeug-Typenbuch. Handbuch der deutschen Luftfahrt- und Zubehör-Industrie 1944 (in German) (Facsimile reprint 1986 ed.). Leipzig: Herm. Beyer Verlag. p. 396.ISBN381120484X.{{cite book}}:ISBN / Date incompatibility (help)
