ALLISON J33 TURBOJET ENGINE

photo 1The J33 engine is a direct descendant of the first production jet engine; the British Whittle engine of the early 1940s. Drawing on lessons learned by its work with Whittle during the Second World War, General Electric Company’s first J33 underwent static testing in January, 1944. Only five months later, a J33 engine flew in the Lockheed XP-80A, having been selected as a replacement the Halford H-1 engine. However, much to the dismay of its GE developers, by November, 1945, the Allison Division of General Motors was given complete responsibility for the development and production of J33 series engines.

Allison went on to produce over 6,600 of the J33s engines which were used in various models of US Air Force aircraft including the F-80, T-33, F-94 and XF-92 as well as the US Navy’s T2V trainer. The J33 was also used in the USAF’s MGM-13 Mace, MGM-1Matador and SM-62 Snark surface-to-surface guided missiles. An understandably disgruntled GE vowed that never again would their development work be turned over for outside production.

The J33 employs a single-stage, double entry, centrifugal-flow compressor for its 14 straight-through combustion chambers. The single-stage axial-flow turbine behind the combustion chamber assembly drives the compressor. The great limiting factor of the design is that almost three-fourths of the power generated is consumed by the compressor and only a fourth is translated into thrust.

The engine on display was originally fitted to the museum’s T-33A Shooting Star.