Hirth HM 504

Summary

The Hirth HM 504 is a four-cylinder air-cooled inverted inline engine. The HM 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.

Hirth HM 504
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 into Hitachi Hatsukaze

ApplicationsEdit

Specifications (HM 504 A-2)Edit

Data from Flugzeug-Typenbuch. Handbuch der deutschen Luftfahrt- und Zubehör-Industrie 1944,[2] Der Flugmotor. Bauteile und Baumuster[3]

General characteristics

  • Type: 4-cylinder air-cooled inverted inline
  • Bore: 105 mm (4.13 in)
  • Stroke: 115 mm (4.53 in)
  • Displacement: 3.980 l (242.87 cu in)
  • Length: 945 mm (37.2 in)
  • Width: 520 mm (20.5 in)
  • Height: 780 mm (30.7 in)
  • Dry weight: 107 kg (236 lb) dry, unequipped
124 kg (273 lb) wet, equipped

Components

  • Valvetrain: 1 inlet and 1 exhaust under-valve per cylinder driven by pushrods and rockers
  • Fuel type: 80 Octane
  • Oil system: dry sump, pressure feed with scavenge
  • Cooling system: air-cooled

Performance

  • Power output:
  • 105 PS (104 hp; 77 kW) at 2,530 rpm (5 minutes) at sea level
  • 95 PS (94 hp; 70 kW) at 2,450 rpm (30 minutes) at sea level
  • 85 PS (84 hp; 63 kW) at 2,360 rpm (max. continuous / cruise) at sea level
  • Specific power: 26.35 PS/l (0.43 hp/cu in; 19.38 kW/l)
  • Compression ratio: 6.2:1
  • Specific fuel consumption: 0.228 kg/PSh (0.510 lb/(hp⋅h); 0.310 kg/kWh) at max continuous
  • Oil consumption: 0.002–0.003 kg/PSh (0.004–0.007 lb/(hp⋅h); 0.003–0.004 kg/kWh) at max continuous
  • Power-to-weight ratio: 0.98 PS/kg (0.44 hp/lb; 0.72 kW/kg)
  • B.M.E.P.: 9.37 atm (9.49 bar; 137.7 psi)

See alsoEdit

Related development

Comparable engines

Related lists

ReferencesEdit

  1. ^ Gunston, Bill (1989). World Encyclopaedia of Aero Engines (2nd ed.). Cambridge, England: Patrick Stephens Limited. p. 77. ISBN 978-1-85260-163-8.
  2. ^ 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. ISBN 381120484X.
  3. ^ Katz, Hans (Dr.Ing) (1940). Der Flugmotor. Bauteile und Baumuster. Luftfahrt Lehrbücherei Band 7. Berlin: de Gruyter.

External linksEdit

  • Göbler-Hirthmotoren Company website (nothing in there about pre-war engines)