Shaping a new generation of helicopters, the PT6T Twin-Pac® has been the workhorse of 1,800 to 2,000 shaft horsepower, medium-class helicopters for four decades and is still going. The standard in its class for rugged dependability and excellent operating economics.


The PT6T Twin-Pac® created the foundation for Pratt & Whitney's success in the global helicopter market, with a heritage that is second to none.

Lasting Dependability


Our customers associate the Twin-Pac® with lasting dependability since its service entry in the 1970s. PT6T engines continue to strong sales today based on the excellent reputation and performance of the Agusta and Bell 212 and 412 helicopters they power and the engine’s unparalleled record of dependability, together with a steady influx of advanced, value-based technologies.

Versatility on a Wide Variety of Applications


The 1,800 to 2,000 shaft horsepower class, twin-power section PT6T has been produced in 11 models and its versatility has been demonstrated on a wide variety of applications around the world. The PT6T power helicopter missions including offshore, emergency medical, search & rescue and utility operations. 

Features of the PT6T Engine Family Continue to Expand

PT6T models are available ranging in shaft horsepower power from 1,800 to over 2,200 shaft horsepower. The latest aerodynamic and material technologies have enabled the PT6T engine to gain more power without significantly increasing in size. Other innovations have further enhanced ease of operation with the introduction of Electronic Engine Control (EEC) on some models. The PT6T basic configuration consists of two PT6A power sections coupled to a combining gearbox with a novel clutch system enabling both twin and single engine operation. The power section configurations are exactly the same as that of the PT6A turboprop, i.e. a two-shaft configuration consisting of a multi-stage compressor driven by a single-stage compressor turbine and an independent shaft coupling the power turbine to the output shaft through the combining reduction gearbox. In fact, the first PT6T-3 power section was the same as that of the PT6A-34 airline turboprop, laying the foundation for airline-type reliability in Pratt & Whitney's first helicopter engine.


The 1,800 to 2,000 shaft horsepower class, twin-power section PT6T has been produced in 11 models.

Engine Thermodynamic Power Class* (SHP) Mechanical Power Class* (SHP) Output Shaft Speed (RPM) Height**(inches) Width**(inches) Length**(inches)
PT6T-9 Series 2,243 1,855 6,000 32.5 43.5 66
PT6T-6 Series 1,970 1,875 6,600 32.5 43.5 66
PT6T-3 Series 1800 to 1,920 1,800 to 1,875 6,000 32.5 43.5 66

* Powers are approximate values at take-off. Available at sea level, standard day, static conditions, uninstalled.

** Dimensions are approximate values.

*** Equivalent Shaft Horsepower: includes estimated equivalent contribution of exhaust thrust.

Applications (10)

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