at all altitudes.
February 1962 The first A-12 prototype (Article 121/ AF Serial No. 60-6924) was trucked to the test site.
April 1962 Support aircraft began arriving at Area 51. These included: six McDonnell F-101B and two F-101F Voodoos for training and photo chase, two T-33A Shooting Stars for proficiency training, one Lockheed C-130 Hercules for cargo transport, one U-8A for administrative use, one Cessna 180 for liaison use (later replaced with a Cessna 210), and a Kaman HH-43 helicopter for search and rescue (later replaced with a UH-1). Two F-104A/G Starfighters (56-0790 and 56-0801) served as chase planes during the OXCART flight test program.
Article 121 made its unofficial first flight at Area 51 with Louis W. Schalk at the controls. He flew the aircraft less than two miles at an altitude of about 20 feet.
The following day, Schalk made a 40-minute flight. Schalk's official first flight, several days later, was witnessed by a number of CIA personnel (including Richard Bissell) and Najeeb E. Halaby, head of the Federal Aviation Administration.
June 1962 Second A-12 airframe (Article 122) arrives at Groom Lake and is mounted on the RCS pylon for three months of testing.
July 1962 SEDAN, a 104-kiloton thermonuclear explosion, created a crater 320 feet deep and 1,280 feet across on Yucca Flat. The radioactive dust cloud drifted northeast over Groom Pass.
October 1962 Shot BANDICOOT detonated in a subterranean shaft with a yield of 12.5 kilotons. Dynamic venting deposited fallout on the Groom Lake area.
November 1962 A Lockheed test pilot flew a U-2 against radar sites at Area 51 to evaluate its radar cross- section. This was shortly after the Cuban Missile Crisis, and may have been precipitated by the loss of a U-2 to a Cuban SA-2 surface-to-air missile on 27 October.
May 1963 During a subsonic engine test sortie in A-12 (Article 123/60-6926), Ken Collins descended into a thick cloud deck. Ice quickly built up in the pitot tube, causing erroneous airspeed readings in the cockpit. The jet suddenly stalled and pitched up, entering an inverted flat spin. Collins ejected, and the A-12 impacted south of Wendover, near the Utah-Nevada border. Secrecy of the OXCART program was maintained by telling the press that a Republic F-105 had crashed. More information here.
August 1963 The first YF-12A (Article 1001/60-6934) made its maiden flight at Area 51 with James Eastham at the controls.
October 1963 A flight of three F-105 Thunderchiefs, led by British exchange pilot Anthony "Bugs" Bendell, was on a practice nuclear weapon delivery sortie about 80 miles north of Nellis AFB when one aircraft experienced an oil pressure malfunction. One F-105 returned to Nellis while Bendell led the stricken craft to the airfield at Groom Lake. After making a pass over the field with no response to distress calls, Bendell advised the student pilot to land. At this point, two F-101 Voodoos intercepted Bendell and forced him to land also.