What best describes a turbine engine?

• A. A turbine engine is an electric motor-driven propulsion unit.
• B. An aircraft engine which consists of an air compressor, a combustion section, and a turbine. Thrust is produced by increasing the velocity of the air flowing through the engine.
• C. A piston engine with mechanical linkage to a propeller.
• D. A ramjet engine that uses no turbine.

Answer: (B)

A turbine engine is a gas turbine propulsion system where air is compressed, fuel is burned in a combustion section, and a turbine extracts energy to drive the compressor, with the remaining energy being turned into thrust as the high-velocity exhaust leaves the engine. This setup—compressor, combustion, turbine—produces thrust by accelerating the air flowing through the engine, which is why it’s described as increasing the air’s velocity through the system. The other options don’t fit: an electric motor-driven propulsion unit describes a non-turbine electric drive; a piston engine with mechanical linkage to a propeller uses reciprocating motion, not a turbine; and a ramjet has no turbine or compressor driven parts.