Westinghouse J40

The Westinghouse J40 was to be a high performance afterburning turbojet engine. It was intended by the Bureau of Aeronautics in early 1946 to power several fighter aircraft, with a rating of 7,500 lbf (33 kN) of thrust at sea level static conditions, but a more powerful 11,000 lbf (49 kN) thrust version for McDonnell F3H Demon proved to be a failure. After a troublesome and delayed development program, failures in service led to the loss of aircraft and pilots and grounding of all J40 powered Demons.

After the program was called a "fiasco" and an "engine flop", the J40 program was terminated in 1955, by which time all the aircraft it was to power were either grounded, canceled or redesigned to use alternative engines. The J40's failure was among those that affected the most military programs and produced the most unflyable aircraft, and would lead to the downfall of the engine division of Westinghouse.^[2] In 1953 Westinghouse worked with Rolls-Royce to offer engines based on the Avon, but Westinghouse was out of the aircraft engine business when this engine also failed to find a United States market.^[3]

Development

J40 powered XF3H-1 prototype on the USS Coral Sea in 1953

Westinghouse Electric Corporation established the Westinghouse Aviation Gas Turbine Division (AGT) in 1945. The J30 was the first American-designed turbojet to run, and was used in the McDonnell FH Phantom. The enlarged J34 was obsolete when introduced, but moderately successful. A new design following the rapid industry progress was needed.

The J40 represented a big opportunity for Westinghouse to become a prominent player in the turbojet engine market. The U.S. Navy showed great confidence in the company when it bet the success or failure of a new generation of jets on Westinghouse over three other engine companies. It was in June 1947 that the Navy's Bureau of Aeronautics contracted for its development. The prototype engine first ran in November 1948. According to an article in the April 1949 edition of the Naval Aviation Confidential Bulletin by Lieutenant Commander Neil D. Harkleroad of the Bureau of Aeronautics Power Plant Division, "The engine has been operating successfully to date." As of that writing, the 50-hour flight substantiation test was to have been accomplished by June 1949 and the 150 hour qualification test by December 1949.

The J40 was designed to deliver twice the thrust of engines currently in service, allowing the J40-WE-8 with afterburner to power many of the new Navy carrier-based fighters with a single engine. These included the Grumman XF10F Jaguar variable sweep wing general purpose fighter, the McDonnell F3H Demon and Douglas F4D Skyray interceptors. Growth to over 15,000 lbf (67 kN) of thrust in afterburner was projected. A version without afterburner, the J40-WE-6, was to power the Douglas A-3D Skywarrior twin-engine carrier-based bomber.

The J40-8 was only a little over 40 inches (1,000 mm) in diameter but 25 feet (7.6 m) long, with accessories and including the afterburner. It weighed almost 3,500 pounds (1,600 kg), the -6 being almost seven feet shorter and about 600 pounds (270 kg) lighter, since it did not have an afterburner.

Decommission

Development of the big engine was protracted. The all-important 150-hour qualification test that was to have been accomplished in December 1949 was not completed until January 1951, a year behind schedule. The afterburner was particularly troublesome – the afterburner version of the engine, the J40-WE-8, did not pass its 150-hour qualification until August 1952. As a result, engines were delivered without afterburners, causing delays in the fighter flight test programs. The XF10F Jaguar had to be tested without an afterburner, and testing had to stop altogether when all J40 powered aircraft were later grounded.

Though the J40 engine had been promised to deliver 10,000 lbf (44 kN) thrust with 15,000 lbf (67 kN) in afterburner for the Demon, actual output was just 6,800 lbf (30,000 N) and the engine was considered unusable because of reliability problems. The A3D would prove successful with alternate engines, but the F3H-1 was relegated to subsonic performance due to the poor performance of this engine. Although considered failures, the F3H-1 could have been competitive with early supersonic Air Force's Century Series fighters had the original engines delivered on their design specifications.^[4]

The F3H Demon single-engine jet fighter was initially a severe disappointment due to the unreliability of the J40. The first production Demons were grounded for a redesign after the loss of six aircraft and four pilots.^[5] Time Magazine called the Navy's grounding of all Westinghouse-powered F3H-1 Demons a "fiasco", with 21 unflyable planes that could be used only for Navy ground training at a loss of $200 million.^[6] One high point of the J40 was the 1955 setting of an unofficial time-to-climb record, in a Demon, of 10,000 feet (3,000 m) in 71 seconds.^[5]

A replacement engine could not simply be fit into the old Demons, as both the wings and fuselage would have to be redesigned and enlarged. The F4D Skyray had been designed to accept larger engines in case the J40 did not work out, and was eventually powered by the Pratt & Whitney J57.

The J40 program was terminated sometime in 1955. All the aircraft it was to power were either canceled or redesigned to use other engines, notably the J57 and the J71.

Applications

• Douglas A-3 Skywarrior
• Douglas F4D Skyray
• Grumman XF10F Jaguar
• McDonnell F3H Demon
• North American X-10

Specifications (J40-WE-8)

Data from ^[7][8]

General characteristics

• Type: Afterburning Turbojet
• Length: 300 in (7.62 m)
• Diameter: 40 in (1.0 m)
• Dry weight: 3500 lb (1590 kg)

Components

• Compressor: Single-Spool, 10 stage Axial
• Combustors: Annular
• Turbine: Two stage

Performance

• Maximum thrust: 7,500 lbf (33.4 kN) dry, 10,500 lbf (46.7 kN) afterburning
• Overall pressure ratio: 5.2:1
• Specific fuel consumption: 0.94 lbf/(lb·h) dry, 2.2 lbf/(lb·h) afterburning
• Thrust-to-weight ratio: 2.14:1 dry, 3:1 afterburning

See also

Related lists

• List of aircraft engines

References

• Dorr, Robert (2006-01-23). "Engine faults 'dashed' Demon's Navy career". Army Times. Retrieved 2008-05-29. 
• Green, William (1967). The World Guide to Combat Planes. Doubleday. 
• Kay, Anthony L. (2007). Turbojet History and Development 1930-1960 Volume 2:USSR, USA, Japan, France, Canada, Sweden, Switzerland, Italy and Hungary (1st ed.). Ramsbury: The Crowood Press. ISBN 978-1861269393. 
• "B-66 Destroyer / A3D Skywarrior". Retrieved 2006-10-12.