Allison T56

Maintenance work on a C-130-Allison T56A-16

T56 on a KC-130 of the USMC

The Allison T56 (civil version Model 501 ) is a shaft turbine from the American manufacturer Allison Engine Company , which has been used primarily in the Lockheed C-130 Hercules transport aircraft since the mid-1950s . With production started in 1954, the T56 is the longest prototype of all large turboprop engines in series production. In 2009 it surpassed the Kuznetsov NK-12 in this regard, with a continuous production period of 55 years . Four main series have been developed that deliver between 3250 and 5250 WPS . After Allison was taken over by Rolls-Royce , the engine was marketed under the name "Rolls-Royce Allison T56".

history

The T56, the first test runs of which took place in the Indianapolis plant in 1949, was a further development of the Allison T38 turboprop engine. A pre-production model was installed in 1954 for test purposes in the nose of a Boeing B-17 (USAF serial no. 44-85747), followed by the test installation of two YT56 each in two Convair CV-340s (serial numbers 91 and 131), which after the conversion as YC -131C. The flight test, which lasted over 3000 hours, was funded by the USAF . The engines delivered an output of 3250 hp each. When they were later sold, the aircraft were given the unofficial designation Convair 770.

A total of 11,000 copies were made by February 1976 and 13,000 by January 1, 1983.

Military variants

T56-A-1A

Propulsion of the C-130A

T56-A-7

Drive of the C-130B with 4050 WPS

T56-A-8

Propulsion of the Grumman E-2 Hawkeye with 4050 WPS

T56-A-9

Successor to the A-1A as a drive for the C-130A, 3750 WPS

T56-A-10W

Drive the ASW version of the Lockheed Electra ( Lockheed P-3 ) with 4500 WPS

T56-A-14

Drive of the P-3A, B, C Orion, 4910 WPS

T56-A-15

Introduction of hollow, air-cooled turbine blades, powering the C-130H, K and HC-130H, N, P and some AC-130 4910 WPS

T56-A-422

Propulsion of the E-2C and C-2A Greyhound, 4910 WPS

T56-A-427

Increased performance and 13% less fuel consumption, propulsion of the E-2C, 5250 WPS

Civil variant

The Model 501 is the civilian version of the T56 and has about 75% of the same components as the military version. The main changes concern the compressor housing, which consists of forged parts, and the relocation of the reduction gear. The 501 can also use JP-1 fuel. With the type certification on May 20, 1955, the 501 became the first turboprop engine from a US manufacturer to be approved for civil use.

commitment

• Convair CV-580
• Grumman C-2 Greyhound
• Grumman E-2 Hawkeye
• Lockheed C-130 Hercules
• Lockheed P-3 Orion
• Lockheed L-188 Electra

Technical specifications

Parameter	Data
Type	Turboprop shaft turbine
compressor	14-stage axial compressor in a two-part welded steel housing. Compression ratio 9.25: 1, mass flow: 14.75 kg / s.
Combustion chamber	Tubular ring combustion chamber
fuel	MIL-J-5624B JP-4 , AvGas 100/130
Fuel consumption	0.245 kg / PS h
turbine	four-stage axial turbine, gas temperature in front of the turbine: 971 ° C (1780 F)
Max. Diameter	0.699 m
length	3.69 m
Weight (dry)	746.8 kg
Nominal shaft power	A-1: 2757 kW (3750 WPS) starting power, 2482 kW (3375 PS) continuous power

literature

• Leonard Bridgman (Ed.): Jane's All The World's Aircraft - 1959-60 , Sampson Low, Marston & Company Ltd., London, 1959
• John WR Taylor (Ed.): Jane's All The World's Aircraft - 1965-66 , Sampson Low, Marston & Company Ltd., London, 1965
• John WR Taylor (Ed.): Jane's All The World's Aircraft - 1978-79 , McDonald and Jane's Publishers, London, 1978
• Mark Lambert (Ed.): Jane's All The World's Aircraft - 1993-94 , Jane's Information Group Ltd., Coulsdon, 1993

Individual evidence

1. ↑ Mention of the flying 5-motor test rig at www.aviationhistorians.net ( memento of the original from July 31, 2013 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.  
2. ↑ YC-131C on www.airliners.net
3. ↑ Jane's 1959-60, p. 680

Web links

Commons : Allison T56  - Collection of Images, Videos and Audio Files

• Story on articles.janes.com (accessed December 25, 2012)