GAM - 87 Skybolt The Douglas GAM - 87 Skybolt ( AGM - 48 under the 1962 Tri - service system ) was an air - launched ballistic missile ( ALBM ) , equipped with a nuclear warhead , developed by the United States during the late 1950s . The UK joined the program in 1960 , intending to use it on their V bomber force . A series of test failures and the development of submarine - launched ballistic missiles ( SLBM s ) eventually led to its cancellation in December 1962 . The UK had decided to base its entire 1960s deterrent force on Skybolt , and its cancellation led to a major confrontation between the UK and US , known today as the " Skybolt Crisis " . This was solved during a series of meetings that led to the Royal Navy gaining the UGM - 27 Polaris missile and construction of the " Resolution " class submarine s to launch them . History . Background . Nuclear weapons theorists had speculated about how to integrate the flexibility of the manned bomber with the invulnerability ( in the attack ) of the ballistic missile . The introduction of useful surface - to - air missile s in the 1950s rendered flight over enemy territory much more dangerous and had greatly reduced the effective deterrent power of a bomber force . Yet the Air Force and military planners were , in the mid - 1950s , reluctant to simply hand over the nuclear strike capability to missiles . After launch , missiles were no longer under positive control , could not be recalled or redirected , and would reach their targets within a matter of minutes after the order to fire . Bombers , in comparison , could be re - directed in flight , and their longer flight times offered greater chance of a negotiated settlement during the attack . Furthermore the missiles of the day were all required to be loaded with their fuels immediately prior to launch , and they could only be launched from above ground after long pre - launch checkouts . This made them vulnerable to attack from the air while they prepared - the first ICBM s , Atlas 1 and Titan 1 were of this type . In contrast , a bomber could be ordered into the air long in advance of an attack , rendering them effectively invulnerable to attack while they " loitered " awaiting orders . With in - air refuelling , the loiter times were on the order of a day if need be . In addition , the inaccuracy of missiles in the 1950s made them useless as precision strike weapons . They could attack area targets like cities , but could not reliably and accurately attack precision strike targets like enemy bomber bases , hardened command and control centers , naval bases , or weapons storage areas . Initially , western ballistic missiles could not even reach such targets , which would be located deep within interior of the Sino - Soviet land mass in Asia . Therefore the potential integration of aircraft with the invulnerability of the ballistic missile was an intriguing prospect to 1950s military planners . ALBMs . Basing the strike package on aircraft offered a flexibility that missiles could not match . For instance , the bombers could stand off from the targets and wait for instructions from secure command centers to attack targets that were missed in an initial strike . Additionally , the bombers could use long - range weapons to strike known air defenses , and then overfly them to deliver precision strikes with freefall nuclear bombs . Secondly , and most importantly , this mode of deployment meant that the strike force was rendered almost invulnerable . The bombers could fly to staging areas well outside the range of even the longest - legged defenses , and strike with impunity . This allowed for gradual escalation and a possible backing down through diplomacy . A ground - based missile cannot be used in the same fashion ; it is either launched or not . If threatened with a nuclear strike , this presents their owners with the ' use them or lose them ' predicament . For the British , their dilemma was a matter of geography and financial resources . No fixed land - based missile system could be credibly installed in the British Isles ; they were well within the range of Soviet air strikes . The limited land mass available meant it would be relatively easy for missile sites to be spotted no matter what security measures were taken . Suitable locations for construction also carried a social and political cost . Fixed land based ballistic missile sites need many thousands of acres per squadron ( typically ten missiles ) ; and the squadrons need to be apportioned over many thousands of square miles , so that no single attack could conceivably destroy them all in one strike . Development . In 1958 several American contractors demonstrated that large ballistic missiles could be launched from strategic bombers at high altitude . The use of astronavigation systems for mid - flight corrections of an inertial guidance platform , similar to that of the US Navy ' s SLBM systems , led to an accuracy similar to that of their existing ground - based missiles . The US Air Force was interested and began accepting bids for development systems in early 1959 . Douglas Aircraft received the prime contract in May , and in turn subcontracted to Northrop for the guidance system , Aerojet for the propulsion system , and General Electric for the reentry vehicle . The system was initially known as WS - 138A and was given the official name GAM - 87 Skybolt in 1960 . At the same time the Royal Air Force was having problems with their IRBM missile project , the Blue Streak , which was long overdue . At the same time , they faced the same problems with the dwindling survivability of their existing nuclear deterrent , the V bomber fleet . The long - range Skybolt would eliminate the need for both the Blue Streak and the Blue Steel II standoff missile , then under development . The Blue Steel II was cancelled in December 1959 and the British cabinet had decided in February 1960 to cancel the Blue Streak . Prime Minister Macmillan met President Eisenhower in March 1960 and agreed to purchase 144 Skybolts for the RAF . By agreement , British funding for research and development was limited to that required to modify the V bombers to take the missile , but the British were allowed to fit their own warheads and the Americans were given nuclear submarine basing facilities in Scotland . Following the agreement the Blue Streak programme was formally cancelled in April 1960 and in May 1960 an agreement for an initial order of 100 Skybolts was concluded . Avro were made an associate contractor to manage the Skybolt programme for the United Kingdom and four different schemes were submitted to find a platform for the missile . A number of different aircraft platforms were considered including a variant of the Vickers VC10 airliner and two of the current V bombers , the Avro Vulcan and Handley Page Victor . It was decided to use the Vulcan to initially carry two missiles each on hardpoints outboard of the main landing gear . Tests . By 1961 , several test articles were ready for testing from USAF B - 52 bombers , with drop - tests starting in January . In January 1961 a Vulcan visited the Douglas plant at Santa Monica to make sure the modifications to the aircraft were electrically compatible with the missile . In Britain , compatibility trials with mockups started on the Vulcan . Powered tests started in April 1962 , but the test series went badly , with the first five trials ending in failure of one sort or another . The first fully successful flight occurred on December 19 , 1962 . Cancellation . By this point the value of the Skybolt system had been seriously eroded . The US Navy ' s Polaris submarine - launched ballistic missile had recently gone into service , with overall capabilities similar to Skybolt , but with " loiter " times on the order of months instead of hours . Additionally , the US Air Force itself was well into the process of developing the Minuteman missile , whose improved accuracy reduced the need for any bomber attacks . Robert McNamara was particularly opposed to the bomber force and repeatedly stated he felt that the combination of SLBMs and ICBMs would render them useless . He pressed for the cancellation of Skybolt as an unnecessary program . The British , on the other hand , had cancelled all other projects to concentrate fully on Skybolt . When McNamara informed them that they were considering cancelling the program in November 1962 , a firestorm of protest broke out in the House of Commons . Jo Grimond noted " Does not this mark the absolute failure of the policy of the independent deterrent ? Is it not the case that everybody else in the world knew this , except the Conservative Party in this country ? " President Kennedy officially cancelled the program on December 22 , 1962 . As the political row grew into a major crisis , an emergency meeting between parties from the US and UK was called , leading to the Nassau agreement . Over the next few days a new plan was hammered out that saw the UK purchase the Polaris SLBM , but equipped with British warheads that lacked the dual - key system . The UK would thus retain its independent deterrent force , although its control passed from the RAF largely to the Royal Navy . The Polaris , a much better weapon system for the UK , was a major " scoop " and has been referred to as “ almost the bargain of the century ” The RAF kept a tactical nuclear capability with the WE . 177 which armed V bombers and later the Panavia Tornado force . The " Skybolt Crisis " was a major event in the eventual downfall of the Macmillan government . A B - 52G launched last XGAM - 87A missile down the Atlantic Missile Range a day after the program was cancelled . In June 1963 , the XGAM - 87A was redesignated as XAGM - 48A . Description . The GAM - 87 was powered by a two - stage solid - fuel rocket motor . Each B - 52 was to carry four missiles , two under each wing on side - by - side pylons , while the Avro Vulcan carried one each on smaller pylons . The missile was fitted with a tailcone to reduce drag while on the pylon , which was ejected shortly after being dropped from the plane . After first stage burnout , the Skybolt coasted for a while before the second stage ignited . First stage control was by eight movable tail fins , while the second stage was equipped with a gimballed nozzle . Guidance was entirely by inertial platform . The current position was constantly updated from the host aircraft though accurate fixes , meaning that the accuracy of the platform inside the missile was not as critical .