The Pratt & Whitney XT57 (company designation: PT5) was an axial-flow turboprop engine developed by Pratt & Whitney in the mid-1950s. The XT57 was developed from the Pratt & Whitney J57 turbojet.

Design and development

One XT57 (PT5), a turboprop development of the J57, was installed in the nose of a JC-124C (BuNo 52-1069), and tested in 1956.

Rated at , the XT57 was the most powerful turboprop engine in existence at the time, and it remains the most powerful turboprop ever built in the United States. The engine had a split-compressor (also known as "two-spool") design.

Intended for use on the Douglas C-132 aircraft, the XT57 turboprop used a Hamilton Standard Model B48P6A propeller with a diameter of , which was the largest diameter propeller to be used in flight at the time. The single-rotation propeller had four hollow steel blades, a maximum blade chord of , a length of , and a weight of .

In the late 1950s, the XT57 was studied for use in a United States Navy-proposed, nuclear-powered conversion of a Saunders-Roe Princess flying boat. Despite not having entered service, the engine was selected because it had passed a Pratt & Whitney 150-hour testing program, which involved running the engine for 5,000–7,000 hours.ANP Program, April 15, 1958: Another engine which we are looking at is the T-57. This is a Pratt and Whitney turboprop engine which was developed for the C-132 airplane. It has passed its 50 hour official qualification. It has passed a 150 hour company test which takes 5 to 7 thousand hour running in total. It has no bugs as far as we can determine. It is now sitting on the shelf and not being used because the C-132 has been cancelled. This as far as we can see is an excellent engine. (Captain Richardson, p. 71)

Variants

T57/PT5 A turboprop engine driving a Hamilton Standard Turbo-Hydromatic propeller, turboprop to be used on the Douglas C-132, a Mach 0.8 speed military transport aircraft.

Applications Douglas JC-124C Globemaster II testbed Douglas C-132 (not built)

Engines on display The XT57 engine is on display at the Pratt & Whitney museum in East Hartford, Connecticut.

Specifications (XT57-P-1)

See also

References Notes

Bibliography

External links