Sunday, October 17, 2010

Rolls Royce/Snecma Olympus 593

The Rolls-Royce/Snecma Olympus 593 was an axial-flow turbojet engine which was developed by the Birtish firm Rolls Royce and the French Snecma to power the Concorde aircraft. The Olympus 593 consisted of a seven-stage low pressure compressor, a seven-stage high pressure compressor, a single-stage high pressure turbine, and a single-stage low pressure turbine. It had an annular chamber with sixteen vaporizing burners, each with twin outlets.

The jet engine draws air in at the front and compresses it. The air then combines with fuel and the engine burns the resulting mixture. The combustion greatly increases the volume of the gases which are then exhausted out of the rear of the engine. The Olympus 593 engine took this gas jet and passed it through straightening vanes - to remove swirl. This gas jet then entered the afterburning jet pipe where a ring of fuel injectors sprayed fuel onto the hot exhaust gases. The resulting combustion greatly improved thrust, although it also led to high fuel consumption. The afterburner was thus only used at takeoff and from just below Mach 1 up to Mach 1.7, the engine supercruised above that speed.

Using the BAC TSR-2's Olympus 320 as a basis for development, the Olympus 593 project began in 1964. Bristol Siddeley of the UK and Snecma Moteurs of France were to share the project. In 1966, Rolls Royce acquired Bristol Siddeley and continued with the project. Development of the original Olympus and engine accessories was under Bristol Siddeley, while Snecma was responsible for the variable engine inlet system, the exhaust nozzle/thrust reverser, the afterburner and the noise attenuation system. Britain was to have a larger share in production of the Olympus 593 as France had a larger share in fuselage production.


Type: axial-flow jet engine
Length: 4039 mm (159 in)
Diameter: 1212 mm (47.75 in)
Dry weight: 3175 kg (7,000 lb)
Compressor: Axial flow, 7-stage low pressure, 7-stage high pressure
Turbine: High pressure single stage, low pressure single stage
Combustors: Nickel alloy construction annular chamber, 16 vaporizing burners, each with twin outlets
Maximum thrust: wet: 169.2 kN (38,050 lbf) dry: 139.4 kN (31,350 lbf)
Overall pressure ratio: 15.5:1
Specific fuel consumption: 1.195 (cruise), 1.39 (SL) lb/(h·lbf)
Thrust-to-weight ratio: 5.4:1