The turbine engine is one of the two most pervasive types of engines used in helicopters—the other being the reciprocating piston engine. Since they are larger and more powerful, turbine engines are more readily utilized in a wider number of rotorcraft platforms than the simpler and smaller piston engine. Helicopters require a higher engine power density than a fixed-wing aircraft due to their hovering capabilities. Turbine engines, though more expensive than piston engines, are the ideal powerplant for modern helicopters.
The gas turbine engine consists of a combustion chamber, compressor, turbine, and gearbox assembly. To function, the compressor pushes the air, feeding it into the combustion chamber where atomized fuel is injected into it. To expand, the combination of fuel and air is ignited. The resulting combustion gas is then forced through a sequence of turbine wheels causing them to turn. The turning turbine wheels supply power to both the engine compressor and the primary rotor system via an output shaft.
A number of rotorcraft platforms utilize a turboshaft engine to power the main transmission and rotor systems of the helicopter. A turboshaft engine is a variant of a gas turbine engine that is engineered to produce shaft power rather than jet thrust. The majority of the energy produced by the mounting gases in a turboshaft engine backs a turbine’s performance instead of producing thrust via the discharge of exhaust gases.