Turbomeca / Bristol Siddeley Nimbus Engine

Country of origin: UK
Built: Leavesden, Herts, England, c. 1958
Manufacturer: Turbomeca / Bristol Siddeley Engines
Engine: 968 shp (722kW) two-stage axial gas generator, single-stage power

Type: Turboshaft engine

Note: Used in Saunders Roe / Westland Scout and Wasp helicopters..

Details: The Bristol Siddeley Nimbus, later known as the Rolls-Royce Nimbus, was a British turboshaft engine developed under license by Blackburn Aircraft Ltd. from the Turbomeca Turmo in the late 1950s. Development was continued by Bristol Siddeley.

The Nimbus is a turboshaft engine comprising a gas generator section, which consists of a three-stage compressor, two axial stages and one centrifugal stage, driven by a two-stage turbine in conjunction with an annular combustion chamber, and a power output section consisting of a single-stage free turbine driving an output shaft via a two-stage reduction gearbox.

It was used in the Saunders Roe / Westland Scout and Wasp helicopters. In the Scout and Wasp the main rotor drive is taken from the front of the gearbox and is transmitted beneath the gas generator via a flexible coupling, while the drive for the tail rotor is taken from the rear of the gearbox.

Examples of Saunders Roe / Wessex Scout and Wasp helicopters can been seen here at The Helicopter Museum,