Allison T56 engines with Aeroproducts propellers, Air Spray L-188 at Red Deer Regional Airport
As the turbo-prop era evolved in the late 1950s, the Aeroproducts hollow-bladed propellers featured self-feathering, reverse pitch, synchronizing/synchrophasing, and electric de-icing. These units were used on the Allison T-56 turboshaft powered Lockheed L-188 Electra, Convair 580, Grumman E2A Hawkeye, and Lockheed C-130A aircraft. The last Aeroproducts propeller unit was delivered in 1974, and the final blade was plated in the Indianapolis Plant 5 on January 12, 1977, marking the end of Aeroproducts propeller line.
The Allison Engine Company was a U.S. aircraft engine manufacturer. In 1929, shortly after the death of James Allison, the company was purchased by the Fisher brothers. Fisher sold the company to General Motors, who owned it for most of its history. The company was acquired by Rolls-Royce plc. in 1995.
The Allison T56 is a single shaft, modular design military turboprop with a 14 stage axial flow compressor driven by a four stage turbine. It was originally developed by the Allison Engine Company for the Lockheed C-130 transport entering production in 1954. It is now produced under Rolls-Royce which acquired Allison in 1995. The commercial version is designated 501-D. With an unusually long and numerous production run, over 18,000 engines have been produced since 1954. It has logged over 200 million flying hours.
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