Volvo RM8

RM8
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. Basically a licensed-built version of the Pratt & Whitney JT8D with a Swedish-designed afterburner, the RM8 was produced by Svenska Flygmotor (now Volvo Aero).^[1] In 1962, the basic JT8D-22 engine was chosen to power the Viggen in absence of a suitable and available engine designed for military use.

Variants and applications

• RM8A - AJ 37 Viggen
• RM8B - JA 37 Viggen

Specifications (RM8B)

Data from Flight International.^[2]

General characteristics

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

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

• Maximum thrust: 72,2kN (16,200 lbf) dry, 125kN (28,100 lbf) wet
• Overall pressure ratio: 16.5:1
• Bypass ratio: 0.97:1
• Turbine inlet temperature: 1,120°C (RM8A)
• Specific fuel consumption: 65 kg/(kN*hr) (0,64lb/(lbf*hr)) dry, 257 kg(kN*hr) (2,52lb/(lbf*hr)) wet
• Thrust-to-weight ratio: 5.4:1

See also

Related development

• Pratt & Whitney J52
• Pratt & Whitney JT8D

Related lists

• List of aircraft engines

References

Notes

1. Gunston, p. 236
2. 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

• Saab Viggen engine trivia
• RM8 history in Swedish