Something extra: The F-101B and atomic air-to-air armament

July 29 commemorates an event that never happened.  On that day in 1958, the United States had been scheduled to conduct an “all-up” test of its newest air defense weapons and systems against live targets, and using the new live nuclear warheads of this new generation of manned interceptors and guided surface-to-air missiles.   All of this was to be controlled from the ground by the amazing  computerized SAGE system, the first large-scale use of radically-new digital computers.

Forming the future close-in defense of major industrial areas would be the Nike Hercules missile, raised to launch position from underground silos and automatically directed by radar command-guidance to intercept a target with either a high explosive warhead or one of two different versions of the W-31 nuclear warhead. 

Defending the perimeter of North American airspace would be left to the new F-101B, still under development but due to enter service the following year.  Designed to a specification to be able to score a minimum of three bomber kills per interceptor, the F-101B carried a brace of nuclear-tipped MB-1 Genie rockets in addition to a pair of Falcon missiles with small high explosive warheads. 

Almost sixty years later, the notion of using nuclear weapons to defend the territory of the United States and Canada seems patently insane.  One live test of the Genie had been conducted a year previously over a small group of observers less than 20,000 feet below an explosion equivalent to 2,000 tons of TNT.   All six of the men involved developed cancer although it did not contribute to the deaths of those who have passed away since the Plumbbob John test in 1957.  The photographer in later years dismissed it as a propaganda stunt, meant to build acceptance by the American people of the notion of using nuclear weapons over their homes and cities by “demonstrating” their safety. 

The Genie rocket, in particular, is singled out as the result of the paranoid atmosphere of the 1950s along with the “Red Scare,” “Communist witch hunts,” and the like.  Playing upon a perception of defending virginal American airspace against the Red hordes crossing the North Pole in massive bomber formations, the Genie is portrayed as a defense against mass formations of Soviet bombers.  History, in its context, shows this perception to be inaccurate.  Facing an enemy force that would use defensive formation tactics during the initial penetration of North American airspace and anticipating the development of high speed, high altitude manned bombers and pilotless cruise missiles, the Genie was an expedient solution to both sets of problems that could be developed and fielded relatively quickly.  The F-101B Voodoo would provide an interceptor with the payload, range, speed, and climb performance to use these weapons effectively, even against targets that could fly higher and faster than the Voodoo.

When development was undertaken in 1954, the near-term threat consisted of jet or turboprop-powered long range bombers that combined high subsonic speed with good altitude capability, cruising at about 40,000 feet.  In Soviet design practice, these bombers retained defensive gun armament that would be used within a small formation of bombers to provide mutual defensive gunfire support against American and Canadian interceptors, which at the time did not have a significant performance edge over the new Tu-95 Bear and M-4 Bison bombers.  Special aircraft modified to “jam” defensive radars and ground-to-air communications would also be fielded alongside the bombers, and were also equipped with guns.  During the initial penetration of enemy airspace, the Soviet bombers would maintain close formation to maximize both defensive firepower and the effectiveness of their electronic “screen” against searching American and Canadian radars.  As they closed to within a couple of hundred miles of their targets, the bombers would split up and proceed individually, relying on speed and confusion for their survival.  By that time, the Soviets had dropped high-yield atomic and hydrogen weapons from their new bombers during tests.  Fearing the consequence of a weapon with 20 to 100 times the destructive power of the bombs that leveled the Japanese cities of Hiroshima and Nagasaki in 1945, American planners needed a defense that would stop them cold.

That weapon came in the form of the MB-1 Genie, armed with a W-25 warhead producing an explosive yield of 1.7 kilotons, about 1/10^th the yield of the “Little Boy” bomb dropped over Hiroshima.  Fielded in 1957 on the best long-range interceptor of the time, the Northrop F-89 Scorpion, the power and the tactical employment of the weapon was hampered by the limited performance capability of the Scorpion.  Woefully underpowered and limited in flight speed due to its straight-wing design, the F-89 would be barely adequate to face new jet bombers, and would be hopelessly outmatched facing bombers or other weapons with increased altitude capabilities or higher speeds.  The Genie did give the older interceptor some capability to make attacks from the front of the target and to “snap-up” and launch at a target at a higher altitude. 

Genie-equipped aircraft were based along the peripheries of the United States in the hope of catching Incoming Soviet bombers in their small defensive formations of three or four aircraft.  Producing a 1,000-foot diameter fireball, the W-25 warhead of the Genie was deemed potent enough to knock down a bomber aircraft within a half mile of the detonation point.  Armed with two Genies apiece, the F-89s stood a chance of knocking down several bombers apiece, if they were lucky to catch them in close formation.  Each bomber destroyed meant a city and its inhabitants saved.

Soviet planners realized the potential of American defensive improvements, and soon began work on measures to negate them.  One was to increase the ceiling to the basic Tu-95 Bear design from 40,000 feet to 55,000 feet, putting it above the combat ceiling of most American interceptors.  Strategic Air Command, the bomber force of the U.S. Air Force, had done the same with its obsolescent B-36 piston-engine bombers under the “Featherweight” program that proved an effective counter against Soviet interceptors.  America had also begun work on a supersonic bomber, the B-58, that could fly at twice the speed of sound and over 50,000 feet.  A pilotless, supersonic cruise missile was also under development, the SM-64 Navaho, which would fly at three times the speed of sound and 70,000 feet. 

Given the apparent recent progress in the Soviet nuclear weapons program, Western technological superiority could no longer be taken for granted.  Although there were glaring gaps in American intelligence efforts at that time in the mid-1950s, it was reasonable to assume that the Soviets were also pursuing parallel developments.  As the historical record now shows, they were, although with variable levels of success.  By the late 1950s, what would have to be in place to counter such developments?  In 1954, the U.S. Air Force had placed all of its eggs in one basket for an advanced new interceptor, the F-102.  Facing innumerable delays with its intricate fire control system, armament, and engines, the Air Force by then had settled on an interim version that was barely supersonic and lacked nuclear weapons capability: the F-102A.  The “ultimate” version, the F-106, would not be ready until the 1959-1960 time frame.  Capable of Mach 2 performance and outstanding climb capability, the F-106 would not have the range needed to adequately defend the perimeter of North American airspace and, limited to one MB-1 Genie rocket, would effectively have half the defensive capability against penetrating Soviet bomber formations.  Something with the range to meet that threat, the payload to carry two Genies, and high supersonic performance approaching that of the F-106 was needed quickly.  The one basic design available that could fulfill that role was for an aircraft under development whose “strategic fighter” mission was already becoming obsolescent, the McDonnell F-101A Voodoo.  With a radius of nearly 1,000 miles, ability to climb to 40,000 feet in two minutes, and a top speed of 1,000 miles-per-hour, the Voodoo could be adapted to meet future threats anticipated for the late 1950s.

Essentially borrowing the already-tested radar, fire control system, and engines from the ongoing F-102A project, the interceptor Voodoo, dubbed the F-101B, would have a top speed approaching Mach 2 and promised an ability to “snap-up” to altitudes of 60,000 feet and more.  Flight testing of the F-101A showed that even with the basic engines the latter capability was possible and that engaging targets at 60,000 feet and higher would be no problem with suitable armament and a fire control system to direct it.  The armament would be mounted on a novel rotary weapons bay door.  On the “outside” would be a pair of conventionally-armed Falcon guided missiles launched from retractable rails.  Rotating the door 180 degrees would expose a pair of large MB-1 Genie rockets, normally nestled inside of the fuselage to reduce drag.  The basic Hughes MG-3 fire control system of the F-102A was modified for a two-seat rather than single-seat presentation and with firing circuits for the Genie to yield the MG-13 fire control system.  Flight testing in the spring and early summer of 1958 demonstrated that the new Voodoo could intercept targets while flying at speeds in excess of Mach 1.4, or about 900 miles-per-hour.  The time came to put it to the test.

The detonation of relatively low-yield air-to-air or surface-to-air warheads high over American cities was a small price to pay in comparison to the utter devastation of even a single Soviet atomic bomb.  As it turns out, the most powerful bomb available to the Soviet Union at that time would have been the RDS-27 with a yield of 215 kilotons, less than the 400-kiloton RDS-6 device that it was derived from, or the 3-megaton RDS-37 device that was to be delayed until 1962 before entering service with Soviet Long-Range Aviation units.  The blast from the RDS-27 would be sufficient to knock down most structures over a radius of several miles from the blast point, and dropped over a large urban area would instantly kill hundreds of thousands, if not millions. 

The videos that we see of grown men seeming to play a child’s game with atomic weapons blasting overhead must be seen in the light of the absolutely obscene destructive power and massive loss of American lives that it was meant to stop.  But even in 1958, not everyone saw it that way.  During the course of July of that year, the governments of Mexico and pre-Castro Cuba  were not at all keen on the opening of a third nuclear weapons test range in the Gulf of Mexico.  Due to the diplomatic sensitivities involved with countries that were then mot on the best of terms with the United States, the live test was canceled just a few days before it was to occur.  The Nike missile was eventually tested with a live W-31 warhead in the Pacific during Operation Dominic, but the Voodoo was never to be tested with a live weapon.  Fortunately, it has also never had occasion to fire one in defense of the United States or Canada, which both went on to operate the Voodoo and its Genie armament into the early 1980s.