PT6A

The Pratt & Whitney Canada PT6A is a turboprop engine widely used in general aviation and regional airliners. Introduced in 1963, it quickly became a popular choice due to its reliability, fuel efficiency, and compact design. The engine is a free-turbine design, meaning the output shaft is mechanically independent of the turbine that drives the compressor. This feature allows the engine to operate at varying propeller speeds, improving efficiency and reducing noise.

The PT6A is known for its distinctive "whine" during operation and its ability to start quickly in cold weather. It has been produced in numerous variants with power outputs ranging from around 500 to over 2000 shaft horsepower. These engines power a vast array of aircraft, including the Beechcraft King Air, Pilatus PC-12, De Havilland Canada DHC-6 Twin Otter, and many others. Its modular construction also facilitates easier maintenance and repair. The PT6A's continuous development and widespread adoption have cemented its status as one of the most successful and enduring turboprop engines ever produced.