Model 96 store
Encyclopedia
The McDonnell Model 96 store was a disposable weapons/fuel pod developed for the F-101A Voodoo
under development by the Strategic Air Command
in the early 1950s.
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
. This change took place in late 1952, while the F-101A was still under development.
At that time, small nuclear weapon
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
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
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 However, the rapid development of compact thermonuclear weapons led to the W-5 being superseded by the W-15 warhead, based on a Los Alamos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
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
.
Flight test
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, 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
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.
F-101 Voodoo
The McDonnell F-101 Voodoo was a supersonic military jet fighter which served the United States Air Force and the Royal Canadian Air Force...
under development by the Strategic Air Command
Strategic Air Command
The Strategic Air Command was both a Major Command of the United States Air Force and a "specified command" of the United States Department of Defense. SAC was the operational establishment in charge of America's land-based strategic bomber aircraft and land-based intercontinental ballistic...
in the early 1950s.
Development
Originally developed as an escort fighterEscort fighter
The escort fighter was a World War II concept for a fighter aircraft designed to escort bombers to and from their targets.The perfect escort fighter had long range, a lengthy combat loiter time to protect the bombers, and enough internal fuel to return home...
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
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....
. This change took place in late 1952, while the F-101A was still under development.
At that time, small nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
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
Armed forces
The armed forces of a country are its government-sponsored defense, fighting forces, and organizations. They exist to further the foreign and domestic policies of their governing body, and to defend that body and the nation it represents from external aggressors. In some countries paramilitary...
Special Weapons Project (AFSWP), Sandia Corporation, and the Atomic Energy Commission
United States Atomic Energy Commission
The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...
(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
McDonnell Aircraft
The McDonnell Aircraft Corporation was an American aerospace manufacturer based in St. Louis, Missouri. The company was founded on July 16, 1939 by James Smith McDonnell, and was best known for its military fighters, including the F-4 Phantom II, and manned spacecraft including the Mercury capsule...
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
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
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
Nautical mile
The nautical mile is a unit of length that is about one minute of arc of latitude along any meridian, but is approximately one minute of arc of longitude only at the equator...
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
Undercarriage
The undercarriage or landing gear in aviation, is the structure that supports an aircraft on the ground and allows it to taxi, takeoff and land...
.
Flight test
Flight test
Flight test is a branch of aeronautical engineering that develops and gathers data during flight of an aircraft and then analyzes the data to evaluate the flight characteristics of the aircraft and validate its design, including safety aspects...
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, 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
Inertia coupling
Inertia coupling is a potentially lethal phenomenon of high-speed flight in which the inertia of the heavier fuselage overpowers the aerodynamic stabilizing forces of the wing and empennage...
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.