1954 interceptor The 1954 interceptor , formally WS - 201A , was a US Air Force project to develop a dedicated interceptor aircraft that would enter service in 1954 . Several aircraft were developed as part of the project , leading to the F - 102 Delta Dagger , F - 106 Delta Dart , XF - 103 Thunderwarrior and , indirectly , the F - 101B Voodoo and F - 104 Starfighter . The electronics and weapons were also destined to become common , including the AIM - 4 Falcon missile and a variety of Hughes Aircraft supplied radar and fire control systems . The project also led , eventually , to the upgrading of the SAGE battle control computers to directly control the interceptors for much of their flight . Although greatly delayed , the resulting systems operated for about 20 years , into the 1980s . Background . The " 1954 interceptor " concept first appeared shortly after the creation of the Air Force from the former US Army Air Force in the post - World War II era . With the re - arrangement of command , several new organizations within the Air Force were created , including Tactical Air Command ( TAC ) and Air Defense Command ( ADC ) , who shared an interest in fighter aircraft . TAC was primarily tasked with offensive duties , but required capable fighters in order to protect their offensive capability . ADC was tasked solely with the defense of the US from enemy attack , in particular long - distance bomber s . Soon after their formation , TAC and ADC started moving away from each other in terms of requirements . In early 1949 ADC started a Request for Proposals ( RFP ) for an advanced interceptor capable of attacking Soviet bombers that were expected to enter service in the early 1950s . Several jet - powered interceptors were already under development at that point , typically adaptations of existing fighters like the F - 86 Sabre ( the D model ) , the F - 94 Starfire ( adapted from the P - 80 Shooting Star ) , with the exception being the all - new F - 89 Scorpion . However these were all subsonic aircraft , and it was felt they would have insufficient performance to effectively intercept high - speed jet bombers known to be under development in the Soviet Union . To counter these threats , ADC prepared a request for an entirely new aircraft expected to perform " hot war " interceptions at supersonic speeds . For reasons that are not clear , they also demanded that the entire system be flown and operated by a single pilot . Given the complexity of the radar systems and the aircraft themselves , this would require an advanced autopilot system that was integrated with the fire control system to lower pilot workload . Given the perceived threat , the new designs were expected to enter service in 1954 . WS - 201A . The Air Force had already realized that the complexity of these newer systems would make integration difficult . In the past , aircraft airframes , engines and weapons were fairly common in size and general layout , allowing existing designs to be modified to change any one component with relative ease . For the 1954 interceptor , new equipment such as missiles and radar systems would be radically different between designs . There was little expectation that one missile could be swapped for another , for instance , due both to different electronic requirements as well as different mechanical layout . To deal with this problem the Air Force introduced the " Weapons Systems " concept , where an entire aircraft ( or other system ) would be ordered as a complete working assembly . Although the parts going into it would be ordered under separate contracts , the requirements of the system as a whole would be known to all of the participants in advance , and one of the companies would be considered " prime " on ensuring all the parts would fit when they were delivered . The 1954 interceptor was the first fighter aircraft ordered under the Weapon System concept , and became " WS - 201A " . Contracts for the various parts making up 201A were sent out as soon as they completed writing them up , starting with the electronics suite , then the missile , and finally airframe and engine . Studies of the electronics suite had started in February 1949 , prior to the 201A specification , and were folded into the project . In January 1950 they sent out the MX - 1179 contract tender to eighteen electronics contractors , but only Bendix , General Electric , Hughes Aircraft , North American Aviation , Sperry , and Westinghouse responded . Hughes was announced as the winner in July 1950 , with what would become the MA - 1 . The original contract specified that MX - 1179 would " direct some type of air - to - air guided missile . " Hughes had already won the MX - 904 contract for a missile known as the GAR - 1 Falcon , and this was selected for 201A mainly because it seemed to be the only one that could be ready in time to meet the 1954 operational date . The airframe and engine contract was issued as MX - 1554 on 18 June 1950 , with a January 1951 deadline for submissions . MX - 1554 also stated that the winner of the airframe contract would also be named the lead " integrator " of the overall Weapon System . When the deadline was reached , nine different proposals were submitted ; Republic Aircraft entered three designs , North American two , and Chance - Vought , Convair , Douglas , and Lockheed each submitted a single design . On 2 July 1951 the Air Force announced that Convair , Lockheed , and Republic had been selected to continue development through the mockup stage , and a winner would be selected at that point . A short while later , the Air Force decided that it also needed a day fighter to combat the new MiG - 15 ' s that were being encountered over Korea . Existing designs like the P - 80 Shooting Star and F - 84 Thunderjet were completely outperformed by the MiG , and while the newer F - 86 Sabre was more than capable of holding its own , it was not clear that would be the case in a war situation in Europe against " front line " Soviet pilots . A plane of considerably higher performance would be needed to guarantee leadership in this role , so the Lockheed entry was redirected toward a day fighter role , evolving into the F - 104 " Starfighter " . Convair and Republic continued on with the original MX - 1554 . It quickly became clear that the Republic design was far too advanced for the 1954 operational entry deadline , and on 11 September 1951 the Convair design was selected as the MX - 1554 airframe and was designated F - 102 . Republic was to continue development of their much more powerful design at a lower priority , becoming the F - 103 . With the introduction of these programs , work on the Republic XF - 91 A , originally slated as an interim interceptor , ended in October 1951 in favor of the new designs . Although the F - 102 had been selected as the " low tech " solution in order to meet the 1954 deadline , practically every part of the 201A system ran into delays . To start with , it was clear that the engine , a Wright - modified version of the Bristol Olympus known as the J67 , would almost certainly not be ready in time for a 1954 service entry . Additionally , the MX - 1179 fire - control system seemed to be a risky proposition , and was another source of potential delay . In December the Air Force decided to reduce the risk by splitting the program in two , producing a reduced - performance version with interim engines and fire control as an " Interim Interceptor " , and continuing with the original design over a longer period of time as the " Ultimate Interceptor " . The Interim design would use the Westinghouse J40 engine , already available although of low power , and the Hughes E - 9 fire - control system , a slightly updated version of the system being used in the F - 86D . Meanwhile , practically every part of the F - 103 program was going wrong . Construction of the airframe required extensive use of titanium in order to handle the high heat loads of extended Mach 3 + flight speeds , and this proved much more difficult to work with than originally expected . The engine , a combination of a Wright - modified version of the Bristol Olympus and a " combined cycle " ramjet from Marquardt , also ran into extensive problems and the J67 eventually ended in failure . Nevertheless , the expected performance was so high the program was allowed to soldier on . Interim measures . The delays seriously upset the original timetable , and it was clear by 1952 that even the " low tech " F - 102 would not be able to meet the 1954 deadline . Although it was expected that the F - 102B would be an excellent long - term solution , something was needed quickly to fill the performance gap between the existing subsonic designs and the continuing delays in the existing F - 102 design . ADC argued that having a second design would also guarantee that problems in either program would be less likely to effect the defense as a whole . The only design with the needed performance at that point in time was the McDonnell F - 88 . This design had originally been ordered by Strategic Air Command ( SAC ) as a long - range " penetration fighter " to escort their heavy bombers . When newer bomber designs offered performance so great that the F - 88 could not hope to keep up with them , TAC then took over the work and started modifying it as a low - level nuclear - armed fighter - bomber , renaming it as the F - 101 Voodoo in 26 November 1951 . ADC also became interested in the Voodoo in October 1952 , but funding from higher headquarters was difficult to find . They rejected modifying the F - 101 , mainly due to its high cost , and suggested attempting solving the problem by increasing the numbers of F - 86Ds and speeding up work on the F - 102 . In April ADC once again asked for the F - 101 , this time justifying it as a longer - range counterpart for use in areas not widely covered by radar . It appears this suggestion was also rejected . However , in August 1953 the Soviets detonated their first hydrogen bomb , and ADC ' s concerns became considerably more urgent . The Air Force Council issued proposals to industry for a new design to work alongside the F - 102 that would help fill the gap between the F - 89 and F - 106 . After short consideration of alternatives — an updated F - 89 and an interceptor version of F - 100 — the two - seat modification of F - 101 was finally selected for development . Known as F - 101B , it would be equipped with the MG - 3 / Falcon suite from the F - 102 , but operated by a weapons officer instead of the pilot . It would greatly simplify the complexity of the system as a whole . Continued problems . Work on the airframes continued through 1952 and into 1953 . NACA wind tunnel tests in early 1953 showed that the maximum altitude of 57 , 000 feet and combat radius of 350 miles predicted by Convair were too optimistic . Drag turned out to be higher than expected , but NACA was able to suggest the application of the recently developed area rule to combat this problem . Convair did not immediately put these recommendations into effect , and the initial two flying prototypes , of an order of 42 aircraft , continued with the original design . When these flew starting in October 1953 , NACA ' s estimates were proven correct , and the F - 102 had only a marginal performance improvement over the F - 86D it was supposed to replace .