Allison J-33

Whittle’s Brother

If the Allison J-33 looks vaguely familiar, it is a direct descendant from the famous jet engine design of Frank Whittle. Whittle’s first jet engine design, the WU, became the first production jet engine, the Whittle W-1. It’s characteristic cluster of combustion chambers gave the Whittle its distinctive shape.

The General Electric Company developed the design for the J-33 out of its work with the Whittle during the Second World War. The first J-33 was tested in January 1944 and became the engine for the Lockheed P-80 Shooting Star. The Allison Division of General Motors took over production of the engine in late 1945.

Deployed in the late 1940s, the J-33 powered the redesignated F-80, the Lockheed T-33 trainer for the USAF and the TV-2 trainer for the U.S. Navy. It also was used in the F-94 Starfire, essentially a two-seat version of the F-80, and very similar to the two-seat T-33. From 1949 to 1955, the Allison works built almost 7,000 of the most popular design, the J-33-A-35, for the USAF alone. The engine on display at the Arkansas Air Museum is a J-33-A-35.

The J-33 was also used in various models of ground-to-ground guided missles for the USAF including the Mace, Matador and Snark. The Allison jet powered the Convair XF-92, the first jet aircraft to use the radical delta-wing designs pioneered by Germany’s Dr. Alexander Lippisch during the 1930s.

The J-33 employed a single-stage, double-entry centrifugal-flow compressor for its fourteen straight through combustion chambers. The single-stage axial-flow turbine behind the combustion chamber assembly drives the compressor. In this design, almost three-fourths of the power generated is consumed by the compressor and only a fourth is translated into thrust. This is the great limiting factor of the design, only 3,900 pounds of thrust for its 1,795 pound weight.

About the Arkansas Air Museum’s J-33

The J-33 on display at the AAM is the A-35 variant, the most widely used of the six designs by Allison. It was donated to the A.A.M. by the Aerospace Engineering Department at Auburn University. It is more than the usual teaching cutaway. The Allison J-33 is a moving model powered by an electric motor. Patrons can press a button to see the stages of the Allison in motion.