The McDonnell Model 96 store was a disposable weapons/fuel pod developed for the

F-101A Voodoo The McDonnell F-101 Voodoo is a supersonic jet fighter which served the United States Air Force (USAF) and the Royal Canadian Air Force (RCAF). Initially designed by McDonnell Aircraft Corporation as a long-range bomber escort (known as a ''p ...

under development by the

Strategic Air Command Strategic Air Command (SAC) was both a United States Department of Defense Specified Command and a United States Air Force (USAF) Major Command responsible for command and control of the strategic bomber and intercontinental ballistic missile c ...

in the early 1950s.

Development

Originally developed as an

escort fighter The escort fighter was a concept for a fighter aircraft designed to escort bombers to and from their targets. An escort fighter needed range long enough to reach the target, loiter over it for the duration of the raid to defend the bombers, an ...

for early Strategic Air Command bombers such as the B-36, the B-47, and the B-50, the mission of the F-101 was changed to that of a "strategic fighter" with equal emphasis on bomber escort and

nuclear weapons delivery Nuclear weapons delivery is the technology and systems used to place a nuclear weapon at the position of detonation, on or near its target. Several methods have been developed to carry out this task. ''Strategic'' nuclear weapons are used primari ...

. This change took place in late 1952, while the F-101A was still under development. At that time, small

nuclear weapon A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions ( thermonuclear bomb), producing a nuclear explosion. Both bom ...

s suitable for high-speed external carriage did not exist. The MK 5 and MK 7 weapons were initially considered for use with the new F-101. However, the existing MK 5 bomb would have produced excessive drag and the MK 7, already deployed by F-84 units, was restricted to a maximum carriage speed of Mach 0.82, prohibiting full use of the high-speed performance of the ''Voodoo''. Since use of the MK 7 did not represent a significant improvement over existing capabilities, a commission of representatives from the Air Force, the

Armed Forces A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...

Special Weapons Project (AFSWP), Sandia Corporation, and the Atomic Energy Commission (AEC) was formed in August 1953 to consider a derivative of the MK 5 as the XW-5/F-101 Joint Project Group. Originally envisioned as a new streamlined casing for the W-5 payload, the new store allowed for the carriage of extra fuel, increasing the combat range of the F-101. The Air Force and the AEC allocated 8 million dollars toward the development of a combination weapons/fuel pod designed, developed, and produced by

McDonnell Aircraft The McDonnell Aircraft Corporation was an American aerospace manufacturer based in St. Louis, Missouri. The company was founded on July 6, 1939, by James Smith McDonnell, and was best known for its military fighters, including the F-4 Phantom ...

Company as the Model 96 store. Initially, the Model 96 store was to weigh between four and five tons and carry a W-5 fission warhead with a yield of about 80 kilotons. Ballistic testing of the pod began with the first drop of a Model 96 "shape" from a B-47 on March 6, 1954. However, the rapid development of compact thermonuclear weapons led to the W-5 being superseded by the W-15 warhead, based on a Los Alamos device nicknamed ''Zombie''. Although somewhat larger and heavier than the W-5, the W-15 boasted a much greater yield of between 1 and 3 megatons. The resulting pod was 32 feet long, 42 inches in diameter, and had capacity for 703 gallons of fuel in addition to the 6,000-pound class W-15 warhead. The Model 96 store attached directly to the belly of the F-101A. A retractable ventral fin allowed the aircraft to rotate during takeoff. The gross takeoff weight of the F-101/Model 96 combination was just less than 50,000 pounds. Over 19,000 pounds of fuel would have been available in this configuration, giving a high-altitude combat radius of 1,287

nautical mile A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters. Historically, it was defined as the meridian arc length corresponding to one minute ( of a degree) of latitude. Today t ...

s and a mission endurance of about five hours. To help contend with the extra weight, the F-101 had provision for dual droppable mainwheels that could be attached to the main

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for takeoff or landing. For aircraft it is generally needed for both. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Marti ...

Flight test Flight testing is a branch of aeronautical engineering that develops specialist equipment required for testing aircraft behaviour and systems. Instrumentation systems are developed using proprietary transducers and data acquisition systems. D ...

ing of the Model 96 store mounted on the F-101A began in July 1955, using the tenth preproduction aircraft, 53-2427, to conduct the tests. However, stability problems due to interference effects between the aircraft and the large pod quickly became apparent. Besides experiencing heavy

buffeting Aeroelasticity is the branch of physics and engineering studying the interactions between the inertial, elastic, and aerodynamic forces occurring while an elastic body is exposed to a fluid flow. The study of aeroelasticity may be broadly clas ...

, the ''Voodoo'' also exhibited instability along the roll and yaw axes when carrying the Model 96 store. Considering to ''Voodoo's'' propensity for

inertia coupling In aeronautics, inertia coupling, also referred to as inertial coupling and inertial roll coupling, is a potentially catastrophic phenomenon of high-speed flight which caused the loss of aircraft and pilots before the design features to counter it ...

and for sensitivity to "pitch-up" at its cruising altitude, this represented a serious problem. Despite the sustained efforts of the McDonnell engineers, these problems were never entirely overcome. In May 1955, late in the development of the Model 96 store, the AEC approved a modified version of the Model 96 carrying the new, lighter W-27 thermonuclear warhead with a yield of 2 megatons. This configuration allowed for a 2,700 pound warhead along with 849 gallons of transferable fuel, and weighed just less than 10,000 pounds. However, the continuing problems with the Model 96/F-101 combination coupled with the rapid development of the MK 28 EX weapon resulted in the demise of the Model 96 program in March 1956.

References

* "Kirtland Gives USAF Nuclear Delivery"; ''Aviation Week'', August 6, 1956, p. 151. * Hansen, Chuck. ''U.S. Nuclear Weapons.'' Arlington, Texas: Aerofax Inc. 1988. . * Kinzey, Bert. ''F-101 Voodoo (Detail and Scale vol. 21)''. Blue Ridge Summit, Pennsylvania 1986. . {{DEFAULTSORT:Model 96 Store Equipment of the United States Air Force