One of several transitional engines designed during the 1950s, the J-34 was an axial flow turbojet engine used in a pair of military aircraft during the period. The J-34 has an all-stage compressor, a single stage combustion chamber, single stage gas turbine and fixed-area exhaust nozzles. It was built by the Aviation Gas Turbine Division of the Westinghouse Electric Corporation in Kansas City. The J-34 was a continuation of the work started with the J-30. Depending on the series, the J-34 produced twice the thrust of its predecessor and its power pushed airframe designers toward more aggressive ideas.
The J-34 was used to modify the Lockheed CP-122 Neptune into the first successful long-range anti-submarine aircraft of the post Second World War period. The original Neptune, the P2-V, used two Wright R3550-32W radial engines for power. The J-34 was mounted in an outbound nascille to extend the range of the Neptune. The redesigned aircraft was the SP-2H.
McDonald Aircraft used the J-34 to create the XF-85 Goblin, the first aircraft specifically designed to be a parasite. Concerns about fight escort for the mammoth, long-range B-36 led to the idea that the gigantic Peacemaker could carry its own fighters to deploy once over enemy territory. Problems in the capture of the Goblin in flight killed the program.
The Neptune and the Goblin showed the initial weakness of the J-34. The turbojets were not used for primary power but were there to boost the aircraft's speed in pursuit. The Neptune cruised on its Wright rotaries.
The U.S. Navy put the J-34 to work in the McDonald F2H Banshee, one of the last of the straight-wing jet fighters, and in the Douglas F3D Skynight. It was the J-34 that gave the F2H it's name thanks the high-pitched wailing sound of the two J-34s. The Skynight had many of the same characteristics of the Banshee, but was employed mostly by Marine squadrons in reconnaissance and night fighting roles. The J-34's major role was its exotic applications. The J-34 was used for low speed power in the Douglas D-558-2 Skyrocket, an experimental research aircraft that was made famous by Scott Crossfield as the first vehicle to fly twice the speed of sound. A pair of late model J-34s were used in Douglas' famous X-3 Stiletto. The J-34 became a replacement engine in the Navy's Convair F-7 SeaDart program, a supersonic interceptor seaplane. It also became the engine for McDonald's entry into the penetration fighter program envisioned by the USAF in the early 1950s, the XF-90.
As mounted, the J-34 has several sections cut away for instructional purposes. That's logical since it is on loan to the Arkansas Air Museum from the Mechanical Engineering Department at the University of Arkansas.