Pratt & Whitney T73

T73/JFTD12
JFTD12-4A mounted on an Erickson S-64E Aircrane
Type	Turboshaft
National origin	United States
Manufacturer	Pratt & Whitney
Major applications	Sikorsky CH-54 Tarhe Sikorsky S-64 Skycrane
Number built	352[1]
Developed from	Pratt & Whitney JT12

The Pratt & Whitney T73 (company designation JFTD12) is a turboshaft engine.^[2] Based on the JT12A, the T73 powered the Sikorsky CH-54 Tarhe and its civil counterpart Sikorsky S-64 Skycrane flying crane heavy-lift helicopters.^[3] Turboshaft versions for naval use are known as the FT12.

Variants

T73-P-1

Basic military model, rated at 4,500 horsepower (3,355 kW) takeoff power and 4,000 horsepower (2,982 kW) maximum continuous power^[4]

T73-P-700

Higher-power military model with improved internal components; rated at 4,800 horsepower (3,579 kW) takeoff power and 4,430 horsepower (3,303 kW) maximum continuous power^[4]

JFTD12A-3

JFTD12A-4A

Civilian equivalent of T73-P-1^[4]

JFTD12A-5A

Civilian equivalent of T73-P-700^[4]

FT12

Marine powerplant

Applications

• Sikorsky CH-54 Tarhe (T73)
• Sikorsky S-64 Skycrane/Erickson Air-Crane S-64 Skycrane (JTFD12)

Specifications (T73-P-1)

T73s on a Sikorsky CH-54 Tarhe

Data from FAA Type Certificate E15EA

General characteristics

• Type: Turboshaft
• Length: 107.0 in (2,718 mm)
• Diameter: 30.0 in (762 mm) maximum
• Dry weight: 966 lbs (438 kg)

Components

• Compressor: nine stage axial compressor
• Combustors: eight cans in annular configuration
• Turbine: axial two stage gas generator turbine and axial two stage free turbine
• Fuel type: aviation kerosene conforming to MIL-I-5161 E Grade I or II

Performance

• Maximum power output: 4,500 horsepower (3,355 kW) takeoff, 4,000 horsepower (2,982 kW) maximum continuous; at sea level at or below -8°C (17°F)
• Turbine inlet temperature: 688°C (1270°F)
• Power-to-weight ratio: 4.66 hp/lb (7.66 kW/kg)

See also

Related development

• Pratt & Whitney JT12

Comparable engines

• Soloviev D-25
• General Electric T64

Related lists

• List of aircraft engines

References

1. Connors, p.285
2. Greg Goebel's Vectorsite
3. Pratt & Whitney JT12 (United States), Aero-engines - Turbojet, Jane's Information Group, 2011.05.09
4. Type Certificate Data Sheet E15EA, US DoT - FAA, 2011.09.12

• Connors, Jack (2010). The Engines of Pratt & Whitney: A Technical History. Reston. Virginia: American Institute of Aeronautics and Astronautics. ISBN 978-1-60086-711-8.
• Federal Aviation Administration Type Certificate Number E15EA, Revision 8 retrieved 14 February 2014

External links

• Atlantic Canadian Aviation: JT12 for Canadair aircraft^{[permanent dead link‍]}