Turbomeca Palouste

The Turbomeca Palouste is a French gas turbine engine, first run in 1952.^[1] Designed purely as a compressed air generator, the Palouste was mainly used as a ground-based aircraft engine starter unit. Other uses included rotor tip propulsion for helicopters.

Palouste
Rolls-Royce license-built Palouste
Type	Gas turbine
National origin	France
Manufacturer	Turbomeca
Major applications	Sud-Ouest Djinn

Design and development

Designed and built by Turbomeca, the Palouste was also built under license in Britain by Blackburn and Rolls-Royce. Originally conceived as an aircraft ground support equipment starter gas generator, it was used also as propulsion for the Sud-Ouest Djinn and other tip-jet powered helicopters.

The Palouste was a very simple unit, its primary purpose being to supply a high flow rate of compressed air to start larger jet engines such as the Rolls-Royce Spey as installed in the Blackburn Buccaneer (this aircraft having no onboard starting system).^[2] Air from the centrifugal compressor was divided between external supply (known as bleed air) and its own combustion chamber.

Sea Vixen on the USS Forrestal in 1962. A Palouste air starter pod is in front.

Several British naval aircraft were adapted to carry a Palouste in a wing-mounted air starter pod installation to facilitate engine starting when away from base.^[3]

A novel use of a surplus Palouste engine was its installation in a custom-built motorcycle known as the Boost Palouste. In 1986 this motorcycle broke an official ACU 1/4 mile speed record at 296 km/h (184 mph). The builder modified the engine to include a primitive afterburner device and noted that pitch changes which occurred during braking and acceleration caused gyroscopic precession handling effects due to the rotating mass of the engine.^[4]

Variants

Palouste IV

The gas generator used to power the Sud-Ouest S.O.1221 Djinn and other tip-jet helicopters.

Palouste IVB

^[5]

Palouste IVC

^[5]

Palouste IVD

^[5]

Palouste IVE

^[5]

Palouste IVF

^[5]

Palouste 502

(P.102 and P.104) Blackburn / Bristol Siddeley / Rolls-Royce production for air-starter units.

Autan

A development of the Palouste delivering a higher mass flow of compressed air.^[6]

Autan 2

1 x axial + 1 x centrifugal compressor stages

Applications

• Bell Model 65
• Fairey Ultra-light Helicopter
• Sud-Ouest Djinn

Specifications (Palouste 4)

Palouste engine fitted to a Sud-Ouest Djinn helicopter

Data from Flight :BRITISH POWER UNITS 1953,^[7][8]

General characteristics

• Type: Gas generator
• Length: 1,233 mm (48.5 in)
• Diameter: 478 mm (18.8 in)
• Dry weight: 90 kg (200 lb)

Components

• Compressor: Single-stage centrifugal flow
• Combustors: Annular combustion chamber
• Turbine: Two-stage axial flow
• Fuel type: Kerosene
• Oil system: Dry sump, pressure spray at 300 kPa (43 psi)

Performance

• Maximum power output: 190 hp (140 kW) equivalent air horsepower at 33,000 rpm at sea level
• Overall pressure ratio: 3.8:1
• Air mass flow: 3.5 kg/s (7.7 lb/s) at 34,000 rpm
• Turbine inlet temperature: TIT 1,070 K (800 °C) ; JPT 793 K (520 °C) at 34,000 rpm
• Fuel consumption: 110 kg/h (240 lb/h)
  
• Oil consumption: 0.2 kg/h (0.44 lb/h)
• Thrust-to-weight ratio:
  
• Air output: 1.1 kg/s (2.4 lb/s) at 350 kPa (51 psi) at 33,000 rpm
• Power-to-weight ratio: 0.61 kg/kW (1 lb/hp)

See also

Related development

• Turbomeca Artouste

Comparable engines

• Napier Oryx

Related lists

• List of aircraft engines