Lockheed D - 21 The Lockheed D - 21 was an American Mach 3 + reconnaissance drone . The D - 21 was initially designed to be launched from the back of its M - 21 carrier aircraft , a variant of the Lockheed A - 12 aircraft . Development began in October 1962 . Originally known by the Lockheed designation Q - 12 , the drone was intended for reconnaissance missions deep in enemy airspace . The D - 21 was designed to carry a single high - resolution photographic camera over a preprogrammed path , then release the camera module into the air for retrieval , after which the drone would self - destruct . Following a fatal accident when launched from an M - 21 , the D - 21 was modified to be launched from a Boeing B - 52 Stratofortress . Only four operational D - 21 flights were made over the People ' s Republic of China before the program was canceled in 1971 . Design and development . In the 1960s , Lockheed ' s secret Skunk Works developed the Mach 3 A - 12 reconnaissance aircraft for the Central Intelligence Agency ( CIA ) . After the downing of Gary Powers ' s U - 2 in 1960 , a number of different concepts were proposed as alternatives . Kelly Johnson , the leader of Skunk Works , developed the concept of a long - range drone that used much of the A - 12 ' s technology . In October 1962 , the CIA and the US Air Force instructed Lockheed to study a high - speed , high - altitude drone concept . Johnson specified speeds of Mach 3 . 3 – 3 . 5 , an operational altitude of , and a range of . It was intended to make a one - way trip , eject its camera payload at the end of the mission for recovery , then self - destruct . It had a double - delta wing similar to the A - 12 ' s wing design . The Q - 12 was to be air - launched from the back of an A - 12 , and used key technology from the A - 12 project , including titanium construction and radar cross - section reduction design features . Johnson wanted to power the Q - 12 with a ramjet engine built by Marquardt for the Boeing CIM - 10 Bomarc long - range surface - to - air missile . Marquardt and Lockheed had already collaborated on several programs and had a close working relationship . The engine , the RJ43 - MA - 11 , required modification , since it was only designed to burn as long as the missile needed to hit a target . In contrast , the Q - 12 ' s engine needed to operate at high temperatures for at least an hour and a half at high altitudes . The modified engine was designated as the RJ43 - MA20S - 4 . A full - scale mockup of the Q - 12 was ready by 7 December 1962 , and had already undergone preliminary tests to measure its radar cross - section . Marquardt had also successfully tested the modified RJ - 43 in its wind tunnel in the meantime . However , the CIA was not enthusiastic about the Q - 12 , mostly because the agency was overextended at the time with U - 2 missions , getting the A - 12 up to speed , and covert operations in Southeast Asia . In contrast , the Air Force was interested in the Q - 12 as both a reconnaissance platform and a cruise missile , and the CIA finally decided to work with the USAF to develop the new drone . Lockheed was awarded a contract in March 1963 for full - scale development of the Q - 12 . The camera and its film magazines with an inertial navigation system were carried in a cramped " Q - bay " below the drone ' s air intake . These components were built into a module that fit into the bay and was known as a " hatch " . The hatch would be ejected at the end of the mission and then snagged out of the air by a JC - 130 Hercules , a technique that had been developed by the Air Force to recover film canisters from satellites . If the C - 130 missed , the hatch was equipped with flotation devices so it could be recovered by ship . Honeywell built the avionics systems ; new construction techniques and materials had to be developed for the systems to withstand the high temperatures , extreme vibrations , and lack of space in the D - 21 . In late 1963 , the project was named " Tagboard " ; the Q - 12 was re - designated D - 21 while the A - 12 version became M - 21 ( D - for " daughter " and M - for " mother " ) . Two of the original 18 A - 12 aircraft were designated as M - 21s with serial numbers 60 - 6940 and 60 - 6941 . The M - 21 was a two - seat version of the A - 12 , with a pylon on the fuselage centerline between the vertical stabilizers to carry the drone in a nose - up attitude . Testing and carrier change . A D - 21 mounted on an M - 21 began captive flight - testing on 22 December 1964 . Aerodynamic covers were initially placed over the D - 21 ' s intake and exhaust to reduce drag , but had to be removed after the first few tests , as a method of discarding them at Mach 3 without damaging the drone or carrier plane could not be devised . The D - 21 was first launched from an M - 21 on 5 March 1966 . The drone was released but stayed close to the M - 21 ' s back for a few seconds , which seemed like " two hours " to the M - 21 crew . A second launch took place on 27 April 1966 , with the D - 21 reaching its operational altitude of 90 , 000 feet ( 27 , 400 m ) and speed of over Mach 3 . 3 , though it was lost due to a hydraulic pump failure after a flight of over . The Air Force ' s interest in the program continued and more D - 21s were ordered after the second launch . A third flight took place on 16 June with the D - 21 flying through its complete flight profile , though its camera hatch was not released due to an electronics failure . The fourth and final launch from an M - 21 on 30 July ended in disaster . Unlike the three previous launches this one was performed straight and level , not in an outside loop to assist in the separation of the drone from the aircraft . The D - 21 suffered engine problems and struck the M - 21 ' s tail after separation , leading to the destruction of both aircraft . The two crew ejected and landed at sea . The pilot , Bill Park , survived , but the Launch Control Officer , Ray Torick , drowned . Following the accident , Johnson suggested launching the D - 21 from a larger aircraft , the Boeing B - 52 Stratofortress , and adding a solid rocket booster to get it up to speed . The drone was modified by adding attachment points on its spine to mate with the carrying pylon on the B - 52 and its belly attachment points were adapted to accommodate the rocket booster necessary to increase its speed and allow its ramjet to operate . Its vertical stabilizer was increased in size by approximately 20 % . The modified drone version was designated " D - 21B " , although there was no " - 21A " version . Two B - 52Hs were modified to carry a pair of drones each by means of two large underwing pylons that replaced the smaller pylons used for the AGM - 28 Hound Dog cruise missiles . The tail gunner ' s and electronic warfare officer ' s stations were replaced with two launch control stations . Command and telemetry systems were added , and high - speed cameras were installed to track the drones as they separated from the pylons . The B - 52Hs could communicate with the D - 21Bs , which had remote control links so that the launch control officer could order it to self - destruct . The solid - fuel booster was both larger and heavier than the drone ; it was long and weighed . It had a folding tail fin on the bottom to stabilize it while the rocket was firing . The booster had a burn time of 87 seconds and a thrust of . During ground handling everyone within was required to wear anti - static straps to prevent any discharge of static electricity from igniting the booster . The first attempted launch of a D - 21B was on 28 September 1967 , but the drone accidentally fell off the B - 52 ' s launch pylon due to a stripped nut on the pylon before the aircraft reached its intended launch point . Johnson admitted that the incident was " very embarrassing " . Three more launches were performed from November 1967 through January 1968 . None were completely successful , so Johnson ordered his team to conduct a thorough review before renewing launch attempts . The next launch was on 10 April 1968 . It also failed as the engine did not ignite . On 16 June , the D - 21B finally made a completely successful flight as it flew at the specified altitude and course for its full range and the hatch was recovered . The next two launches were failures , followed by another successful flight in December . A test in February 1969 to check the inertial navigation system with an actual mission profile was a failure . The next two flights in May and July succeeded . Operational history . Four operational missions with the D - 21B took place under the codename of " Senior Bowl " . These were conducted over the People ' s Republic of China from 9 November 1969 to 20 March 1971 to spy on the Lop Nor nuclear test site . The USAF ' s 4200th Support Squadron , based at Beale Air Force Base , California , flew the missions , usually from Andersen Air Force Base in Guam . The Chinese never spotted the D - 21B , but it failed to turn around and continued straight on , crashing somewhere in the Soviet Union . Another test flight was conducted on 20 February 1970 in a successful attempt to correct any problems . The second operational mission , however , was not until 16 December 1970 . The D - 21B made it all the way to Lop Nor and back to the recovery point , but the hatch had a partial parachute failure and was lost at sea . During the third operational mission , on 4 March 1971 , the D - 21B flew to Lop Nor and returned , jettisoning the hatch . It deployed its parachute , but the midair recovery failed . The destroyer that tried to retrieve the hatch from the water ran it down and it sank . The fourth , and last , flight of the D - 21B was on 20 March 1971 . It was lost over China on the final segment of the route . Wreckage of this lost D - 21B was found by local authority in Yunnan province , China . In 2010 , after being dumped in the junkyard of China Aviation Museum for years , the wreckage was finally officially moved to the exhibition area . On 23 July 1971 , the D - 21B program was canceled , due to the poor success rate , the introduction of a new generation of photo reconnaissance satellites , and President Richard Nixon ' s rapprochement with China . A total of 38 D - 21 and D - 21B drones were built with 21 expended in launches . The remaining 17 were initially stored at Norton Air Force Base , California , then moved to Davis - Monthan Air Force Base " boneyard " near Tucson , Arizona , in 1976 and 1977 . With the base open to the public , the D - 21 drones were quickly spotted and photographed . The Air Force called them GTD - 21Bs with the GT standing for Ground Training . The fate of the D - 21 that had disappeared on the first operational flight was finally revealed in February 1986 when an official from the CIA returned a panel to Ben Rich that he had been given by a Soviet KGB agent . The drone had self - destructed over Siberia and the Soviets had recovered the wreckage . The Tupolev design bureau reverse - engineered the wreck and came up with plans for a Soviet copy , named the " Voron " ( Raven ) , but it was never built . In the late 1990s , NASA considered using a D - 21 to test a hybrid " rocket - based combined cycle " engine , which operates as a ramjet or rocket , depending on its flight regime . This idea was abandoned , and NASA used a derivative of the agency ' s X - 43A hypersonic test vehicle for the experiments . Specifications ( D - 21 ) . Sources : Pace , Landis & Jenkins , Donald