Which are the major sections of a typical gas turbine engine?

• A. Inlet/air intake, compressor, combustor (burner), turbine, exhaust, and the accessory systems (fuel, lubrication, starting, ignition).
• B. Inlet, rotor, stator, housing, exhaust, and cooling system.
• C. Intake, compressor, gearbox, cooler, exhaust, and control system.
• D. Inlet, compressor, combustor, turbine, exhaust, with no accessory systems.

Answer: (A)

Gas turbine engines are built around a continuous flow of air through a sequence of major sections: inlet or air intake to bring in air, a compressor to raise its pressure, a combustor (burner) where fuel is added and burned, a turbine where the hot gases expand to produce work, and the exhaust to release the spent gases. The engine also relies on accessory systems that supply fuel, lubrication, starting, and ignition to enable operation from cold start onward. This combination—inlet, compressor, combustor, turbine, exhaust, plus the accessory systems—captures the essential structure and function of a typical gas turbine.

Other descriptions mix in components that aren’t considered the primary sections of the engine (such as rotor/stator/housing or cooling systems) or add items like a gearbox or a separate control system, which aren’t part of the basic major sections. They also omit the vital accessory systems, which are necessary for starting and running the engine.