Volvo RM8

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RM8
VolvoAero RM8.JPG
An RM8 on display at the Swedish Air Force Museum
Type Turbofan
Manufacturer Volvo Flygmotor/Pratt & Whitney
First run 1964
Major applications Saab 37 Viggen
Developed from Pratt & Whitney JT8D
An RM8 on display at the Swedish Air Force Museum

The Volvo RM8 is a low-bypass afterburning turbofan jet engine developed for the Saab 37 Viggen fighter. In 1962, the Pratt & Whitney JT8D-1 engine was chosen to power the Viggen in absence of a suitable and available engine designed for military use. Basically a licensed-built version of the JT8D, heavily modified for supersonic speeds, with a Swedish-designed afterburner, the RM8 was produced by Svenska Flygmotor (later known as Volvo Aero).[1]

Variants and applications[edit]

Since the original engine was constructed for subsonic speeds, most part of the engine had to be redimensioned for the higher Mach-speeds in a military aircraft. Fans and turbine were altered, a new burn-chamber designed and a totally new fuel-control system for both engine and afterburner.[2]

The flight envelope for the fighter-version demanded both more power and better compressor stall margins. This led to a new fan-stage (the so-called "0-stage") was introduced, making the engine longer. This led to a total redesign of the fans, the low-pressure compressor and the burn-chambers.[3]

Specifications (RM8B)[edit]

Data from Flight International.[4]

General characteristics

  • Type: Afterburning turbofan
  • Length: 6.23 m (20.44 ft)
  • Diameter: 1.03 m (40.55 in)
  • Dry weight: 2,350 kg (5,180 lb)

Components

  • Compressor: Axial flow, 3-stage fan, 3-stage LP, 7-stage HP
  • Combustors: 9 chambers in can-annular arrangement, four injectors per chamber

Performance

See also[edit]

Related development
Related lists

References[edit]

Notes
  1. ^ Gunston, p. 236
  2. ^ JAS 39 Gripen, p.32, Gunnar Lindqvist / Bo Widfeldt, Air Historic Research AB, 2003, ISBN 91-973892-5-0
  3. ^ JAS 39 Gripen, p.32&35, Gunnar Lindqvist / Bo Widfeldt, Air Historic Research AB, 2003, ISBN 91-973892-5-0
  4. ^ Flight International 14 Dec 1972
Bibliography
  • Gunston, Bill (1999). The Development of Piston Aero Engines, 2nd Edition. Sparkford, Somerset, England, UK: Patrick Stephens, Haynes Publishing. ISBN 0-7509-4478-1. 

External links[edit]