The gas turbine has three main sections:

The Compressor
The compressor draws air into the engine, pressurises it, and delivers it to the combustion chamber. It is driven from the turbine by a shaft. There are two types of compressor: the centrifugal flow impeller type, as used in Whittle’s designs, and the axial flow type which has several stages of alternate rotating and stationary aerofoil blades. The rotor blades are mounted on a drum and the stator vanes in the compressor casing. Axial compressors can achieve compression ratios in excess of 40:1. At full power the blades of the Trent 892 compressors rotate at 1000mph (1,600kph) and take in 2,600lb (1,200kg) of air per second.

The Combustion System
The combustion chamber receives air from the compressor which mixes with fuel sprayed from nozzles in the front of the chamber. The mixture is burned at temperatures up to 2,000ºC to generate the maximum possible heat energy. The burning process is initiated by igniter plugs, isolated after start-up, and remains continuous until the fuel supply is shut off. At cruise the Trent 892 uses about 1,000 gallons (4,500 litres) of fuel per hour.

The Turbine
Each turbine consists of one or more stages of alternate stationary and rotating aerofoil-section blades. The rotating turbine blades are carried on discs, which are connected by a shaft to the compressor. The stationary blades - nozzle guide vanes - are housed in the turbine casing. The turbine extracts energy from the hot exhaust gases to drive the compressor. In the Trent 892, the first turbine has to be air-cooled as it operates in a gas stream temperature of around 1,500ºC - hotter than the melting point of the blade material. The total power generated by the engine is 250,000hp (200,000kW) and the exhaust gases exit at 1,000mph (1,600kph).