Convair Kingfish The Convair Kingfish reconnaissance aircraft design was the ultimate result of a series of proposals designed at Convair as a replacement for the Lockheed U - 2 . " Kingfish " competed with the Lockheed A - 12 for the Project Oxcart mission , and lost out to that design in 1959 . Background . Problems with the U - 2 . Before the U - 2 became operational in June 1956 , CIA officials had estimated that its life expectancy for flying safely over the Soviet Union would be between 18 months and two years . After overflights began and the Soviets demonstrated the ability to track and attempt to intercept the U - 2 , this estimate was adjusted downward . In August 1956 , Richard Bissell reduced the number to six months . To extend the useful life of the U - 2 , the CIA started Project Rainbow , which added various countermeasures to confuse the Soviet radars and make planning an intercept more difficult . The anti - radar methods developed under Rainbow consisted of , first , a diffusing coating for the fuselage , and , second , a series of wires strung along the fuselage and the wing edges that were supposed to cancel out radar reflection from the airframe by " broadcasting " a similar return but out - of - phase . Several Rainbow - equipped flights were made , but the Soviets proved able to track the aircraft regardless . The weight of the equipment also had the side - effect of lowering the aircraft ' s maximum cruise altitude , making it more vulnerable to interception . Rainbow was canceled in 1958 . Replacing the U - 2 . As early as 1956 Bissell had already started looking for an entirely new aircraft to replace the U - 2 , with an emphasis on reducing the radar cross section as much as possible . High - altitude flight would still be useful to avoid interception by aircraft , but did little to help against missiles . By reducing the RCS , the radars guiding the missiles would have less time to track the aircraft , complicating the attack . In August 1957 these studies turned to examining supersonic designs , as it was realized that supersonic aircraft were very difficult to track on radars of that era . This was due to an effect known as the blip - to - scan ratio , which refers to the " blip " generated by an aircraft on the radar display . In order to filter out random noise from the display , radar operators would turn down the amplification of the radar signal so that fleeting returns would not be bright enough to see . Returns from real targets , like an aircraft , would become visible as multiple radar pulses all drawn onto the same location on the screen , and produced a single brighter spot . If the aircraft is moving at very high speeds , the returns would be spread out on the display . Like random noise , these returns would become invisible . Project Gusto . By 1957 so many ideas had been submitted that Bissell arranged for the formation of a new advisory committee to study the concepts , led by Edwin Land under the designation Project Gusto . The committee first met in November to arrange for submissions . At their next meeting , on 23 July 1958 , several submissions were studied . Kelly Johnson of Lockheed presented the Archangel I design , which could cruise at Mach 3 for extended periods in order to take advantage of blip / scan spoofing , although it was not designed for reduced RCS . Convair proposed a parasite aircraft that was launched in the air from a newer version of the B - 58 Hustler that was then being studied . The Navy introduced a submarine - launched inflatable rubber vehicle that would be lifted to altitude by a balloon , boosted to speed by rockets , and then cruise using ramjets . Johnson was asked to provide a second opinion on the Navy design , and the committee arranged to meet again shortly . At the next meeting , in September 1958 , the designs had been further refined . Johnson reported on the Navy concept and demonstrated that it would require a balloon a mile wide for launching ; the submission was then dropped . Boeing presented a new design for a long liquid hydrogen powered inflatable design . Lockheed presented several designs ; the Lockheed CL - 400 Suntan looked like a scaled - up F - 104 Starfighter powered by wingtip - mounted hydrogen - burning engines , the G2A was a subsonic design with a low radar cross - section , and the A - 2 was a delta wing design using zip fuel – powered ramjets . Convair entered their parasite design , slightly upgraded and intended to fly at Mach 4 . FISH . Convair ' s parasite design was derived from the Super Hustler concept which Convair had proposed to the Air Force . The original version had been a two - part design , the rear portion being an unmanned booster powered by a pair of ramjets , and the front portion a manned aircraft with a single ramjet . The Super Hustler could either be launched from under a B - 58 bomber or from a ground trailer using a booster rocket . For the air launch , the Super Hustler would be carried to a speed of Mach 2 at , and released . All three ramjets would fire for " boost " , after which the rear portion would fall away . The unmanned booster could also be used as a weapon , if armed . For Project Gusto , the concept had been simplified and reduced to a single aircraft . Code - named FISH or First Invisible Super Hustler , the aircraft was based on a lifting body design that bears some resemblance to the Asset of a few years later . It differed in having the nose taper down to a flat horizontal line instead of the rounded delta of the ASSET , and the fuselage was not as large at the rear . Two vertical control surfaces were placed on either side of the fuselage at the rear , and a small delta wing covered about the rear third of the aircraft . It was to be powered by two Marquardt RJ - 59 ramjets during the cruise phase , providing a cruise speed of Mach 4 at , climbing to as it burned off fuel . In order to handle the intense heat generated by skin friction at these speeds , the leading edges of the nose and wings were built of a new " pyroceram " ceramic material , while the rest of the fuselage was made of a honeycomb stainless steel similar to the material for the proposed XB - 70 Valkyrie . After completing its mission , the aircraft would return to friendly airspace , slow , and then open intakes for two small jet engines for the return flight at subsonic speeds . Lockheed ' s entry had also changed during the research phase . Their original submission was the Archangel II ( A - 2 ) , another ramjet - powered design , but one that was ground - launched using large jet engines . The committee didn ' t find either entry particularly interesting , and when the B - 58B was canceled by the Air Force in 1959 , the entire " Fish " concept was put in jeopardy . There was some design work on converting the existing A - model Hustlers as " Fish " carriers , but the aircraft appeared to have limited capabilities for launching the " Fish " , and the Air Force was unwilling to part with any of their bombers anyway . The committee asked both companies to return with another round of entries powered by the Pratt & Whitney J58 turboramjet . Kingfish . After cancellation of the B - 58B in mid - 1959 , Convair turned to a completely new design , similar to their earlier entry in name only . The new " Kingfish " design had much in common with the Convair F - 106 Delta Dart , using a classic delta wing layout like most of Convair ' s products . It differed in having two of the J58 engines buried in the rear fuselage , and twin vertical surfaces at the rear . The intakes and exhausts were arranged to reduce radar cross section , and the entire aircraft had the same sort of angular appearance as the later Lockheed F - 117 . The leading edges of the wings and intakes continued to use pyroceram , while other portions used a variety of materials selected for low radar reflection , including fiberglass . The new engines reduced the cruise speed to Mach 3 . 2 compared to the " Fish " ' s Mach 4 . 2 , but range was increased to about 3 , 400 nm ( 6 , 300 km ) . In July 1959 , Lockheed and Convair presented preliminary designs and RCS estimates to the review panel . Lockheed ' s was designated the A - 12 , and was a variation of their A - 11 design . President Eisenhower was briefed on 20 July and he approved moving ahead with a final decision . On 20 August , the companies presented their final designs for Kingfish and the A - 12 . Lockheed ' s design was estimated to have longer range , higher altitude and lower cost . Johnson expressed skepticism of Convair ' s claimed RCS , and complained that they had given up performance to achieve it : " Convair have promised reduced radar cross section on an airplane the size of A - 12 . They are doing this , in my view , with total disregard for aerodynamics , inlet and afterburner performance . " On 28 August 1959 , Johnson was notified that the A - 12 had been selected . The decision was based not only on aircraft performance but also on contractor performance . During the U - 2 project , Lockheed had proven its ability to design advanced aircraft in secret , on - time , and under - budget . In contrast , Convair had massive cost overruns with the B - 58 and no secure R & D facility similar to the Skunk Works . Lockheed promised to lower the RCS in a modified version of the A - 11 known as the A - 12 , and that sealed the deal . The A - 12 entered service with the CIA in the 1960s , and was slightly modified to become the Air Force ' s SR - 71 . Aftermath . Some small - scale work on the " Kingfish " continued even after the choice of the A - 12 , in case the A - 12 ran into problems . This did not occur , and the " Kingfish " funds soon disappeared . The CIA continued studies into even higher performance aircraft , and studied replacing the A - 12 under Project Isinglass . Isinglass focused on a new design blending features of the General Dynamics F - 111 and " Kingfish . " The new design aimed to produce a new reconnaissance aircraft capable of reaching up to Mach 5 at an altitude of . The CIA felt that the extra performance would not be enough to protect it from missile systems already capable of attacking the A - 12 , and nothing came of the project . The idea of spoofing radars through their blip / scan turned out to not work . Among other effects , it was discovered that the engine ejectors produced significant reflections . Lockheed proposed adding caesium to the jet fuel to create a cloud of ions that would help mask this effect . Additionally , since the entire idea relied on problems in the radar display systems , upgrades to these systems could render the entire concept moot . In the end , the A - 12 was considered too vulnerable and was only flown over secondary nations like Vietnam . The failure of the A - 12 ' s attempts to avoid radar was proven when the Vietnamese proved able to track the A - 12 with some ease , even firing on it on several occasions and causing minor damage on one occasion in 1967 .