Armstrong Siddeley Viper

The Viper is a British turbojet engine developed and produced by Armstrong Siddeley and then by its successor companies Bristol Siddeley and Rolls-Royce Limited. It entered service in 1953 and remained in use with the Royal Air Force, powering its Dominie T1 navigation training aircraft until January 2011.

The example here was taken from our Avro Shackleton MR3 Phase 3, where it was used in the two outer nacelles to provide additional thrust where needed.

General characteristics

  • Type: Turbojet
  • Length: 64.0 in (1,625 mm)
  • Diameter: 24.55 in (624 mm)
  • Dry weight: 549 lb (249 kg)


  • Maximum thrust: 2,700 lb (12 kN) at 13,800 rpm
  • Overall pressure ratio: 4.3:1
  • Specific fuel consumption: 1.09 lb/hr/lb oil consumption=1.25 pints/hr (0.7l/h)
  • Thrust-to-weight ratio: 4.9:1


  • Compressor: Seven stage axial
  • Combustors: Annular, 24 burners
  • Turbine: Single stage
  • Fuel type: AVTUR, AVTAG
  • Oil system: scavenge, metered