Editing Area 51 (section)

===D-21 Tagboard===

{{Main|Lockheed D-21}}
[[File:M21Ship2-cropped.jpg|thumb|The D-21 mounted on the back of the M-21. Note the intake cover on the drone, which was used on early flights.]]

Following the loss of [[Gary Powers]]' [[Lockheed U-2|U-2]] over the Soviet Union, there were several discussions about using the A-12 OXCART as an unpiloted drone aircraft. Although Kelly Johnson had come to support the idea of drone reconnaissance, he opposed the development of an A-12 drone, contending that the aircraft was too large and complex for such a conversion. However, the Air Force agreed to fund the study of a high-speed, high-altitude drone aircraft in October 1962. The Air Force interest seems to have moved the CIA to take action, the project designated "Q-12". By October 1963, the drone's design had been finalized. At the same time, the Q-12 underwent a name change. To separate it from the other A-12-based projects, it was renamed the "D-21". (The "12" was reversed to "21"). "Tagboard" was the project's code name.<ref name="Peebles"/>{{rp|121}}

The first D-21 was completed in the spring of 1964 by Lockheed. After four more months of checkouts and static tests, the aircraft was shipped to Groom Lake and reassembled. It was to be carried by a two-seat derivative of the A-12, designated the "M-21". When the D-21/M-21 reached the launch point, the first step would be to blow off the D-21's inlet and exhaust covers. With the D-21/M-21 at the correct speed and altitude, the LCO would start the ramjet and the other systems of the D-21. "With the D-21's systems activated and running, and the launch aircraft at the correct point, the M-21 would begin a slight pushover, the LCO would push a final button, and the D-21 would come off the pylon".<ref name="Peebles"/>{{rp|122}}

Difficulties were addressed throughout 1964 and 1965 at Groom Lake with various technical issues. Captive flights showed unforeseen aerodynamic difficulties. By late January 1966, more than a year after the first captive flight, everything seemed ready. The first D-21 launch was made on 5{{nbsp}}March 1966 with a successful flight, with the D-21 flying 120 miles with limited fuel. A second D-21 flight was successful in April 1966 with the drone flying 1,200 miles, reaching Mach 3.3 and 90,000 feet. An accident on 30 July 1966 with a fully fueled D-21, on a planned checkout flight, suffered from an [[unstart]] of the drone after its separation, causing it to collide with the M-21 launch aircraft. The two crewmen ejected and landed in the ocean 150 miles offshore. One crew member was picked up by a helicopter, but the other, having survived the aircraft breakup and ejection, drowned when sea water entered his pressure suit. Kelly Johnson personally cancelled the entire program, having had serious doubts about its feasibility from the start. A number of D-21s had already been produced, and rather than scrapping the whole effort, Johnson again proposed to the Air Force that they be launched from a [[Boeing B-52 Stratofortress|B-52H]] bomber.<ref name="Peebles"/>{{rp|125}}

By late summer of 1967, the modification work to both the D-21 (now designated D-21B) and the B-52Hs was complete. The test program could now resume. The test missions were flown out of Groom Lake, with the actual launches over the Pacific. The first D-21B to be flown was Article 501, the prototype. The first attempt was made on 28 September 1967 and ended in complete failure. As the B-52 was flying toward the launch point, the D-21B fell off the pylon. The B-52H gave a sharp lurch as the drone fell free. The booster fired and was "quite a sight from the ground". The failure was traced to a stripped nut on the forward right attachment point on the pylon. Several more tests were made, none of which met with success. However, the fact is that the resumptions of D-21 tests took place against a changing reconnaissance background. The A-12 had finally been allowed to deploy, and the [[Lockheed SR-71 Blackbird|SR-71]] was soon to replace it. At the same time, new developments in reconnaissance satellite technology were nearing operation. Up to this point, the limited number of satellites available restricted coverage to the Soviet Union. A new generation of reconnaissance satellites could soon cover targets anywhere in the world. The satellites' resolution would be comparable to that of aircraft but without the slightest political risk. Time was running out for the Tagboard.<ref name="Peebles"/>{{rp|129}}

Several more test flights, including two over China, were made from [[Beale AFB]], California, in 1969 and 1970, to varying degrees of success. On 15 July 1971, Kelly Johnson received a wire canceling the D-21B program. The remaining drones were transferred by a C-5A and placed in dead storage. The tooling used to build the D-21Bs was ordered destroyed. Like the A-12 Oxcart, the D-21B Tagboard drones remained a Black airplane, even in retirement. Their existence was not suspected until August 1976, when the first group was placed in storage at the [[Davis-Monthan AFB]] [[Military Storage and Disposition Center]]. A second group arrived in 1977. They were labeled "GTD-21Bs" (GT stood for ground training).<ref name="Peebles"/>{{rp|132}}

Davis-Monthan is an open base, with public tours of the storage area at the time, so the odd-looking drones were soon spotted and photos began appearing in magazines. Speculation about the D-21Bs circulated within aviation circles for years, and it was not until 1982 that details of the Tagboard program were released. However, it was not until 1993 that the B-52/D-21B program was made public. That same year, the surviving D-21Bs were released to museums.<ref name="Peebles"/>{{rp|132–133}}