In 1951 the U.S. Air Force announced a requirement for a medium-size logistic and tactical transport aircraft, which resulted in the workhorse Lockheed C-130 Hercules. With Air Force support, Allison designed the T56 turboprop for the C 130 and first flight tested the engine in 1954 in the nose of a Boeing B-17 test bed aircraft.

The first production installation was on the Lockheed YC 130, which first flew in August 1954. The commercial version of the T56, the 501, powered the Lockheed Electra L-188, which entered service with Eastern Airlines in 1959. With some models rated in excess of 5,000 horsepower, the T56 has powered several other large military and commercial aircraft, such as the Lockheed P-3, Convair 580, Grumman C-2 and E-2, and Aerospace Lines Super Guppy.

Allison T56-A-1

In 1951, the U.S. Air Force announced a requirement for a medium-size logistic and tactical transport aircraft, which resulted in the workhorse Lockheed C-130 Hercules. With support of the Air Force, Allison designed the T56 turboprop for the C-130, and first flight-tested the engine in 1954 in the nose of a Boeing B-17 testbed aircraft. The first production installation was on the Lockheed YC-130, which first flew on August 23, 1954.

The engine displayed here, a T56-A-1 first-generation (Series I) military model, powered the Lockheed C-130A and Convair YC-131C Samaritan. Its commercial equivalent, the 501-D13, powered airliners including the Lockheed Electra L-188, which entered commercial service with Eastern Airlines in January 1959. This highly successful turboprop has powered several other large military and commercial aircraft, such as the Lockheed P-3 Orion, Grumman C-2 Greyhound and E-2 Hawkeye, and Aerospace Lines Super Guppy aircraft.

Gift of Allison Division, General Motors Corporation

Type: Turboprop

Power/Speed: 2796 kW (3,750 eshp) at 13,820 rpm

Compressor: 14-stage axial-flow

Combustor: Cannular, 6 flame tubes

Turbine: 4-stage axial-flow

Manufacturer: Allison, Indianapolis, IN

A19620071000