Tonopah Test Range Airport (IATA: XSD, ICAO: KTNX, FAA LID: TNX), at the Tonopah Test Range (Senior Trend project site PS-66, abbreviated TTR) is 27 NM (50 km; 31 mi) southeast of Tonopah, Nevada, and 140 mi (230 km) northwest of Las Vegas, Nevada. It is a major airfield with a 12,000 ft × 150 ft (3,658 m × 46 m) runway, instrument approach facilities, and nighttime illumination. The facility has over fifty hangars and an extensive support infrastructure.

Tonopah is controlled by the USAF Air Combat Command. The primary use of this airport, to public knowledge, is to shuttle government employees to the weapons test range from Harry Reid International Airport in Las Vegas. Historically it has been used for classified Air Force operations.

The primary (paved) access to the facility is off of U.S. Route 6 at the north end of the airport. Dirt road access points also exist on the south and east sides of the range. The site is plainly visible from commercial airliners, which pass 17 NM (31 km; 20 mi) north of the base on transcontinental flights.

The Tonopah Range Airport first opened in 1957, supporting operations on the test range itself, which was used for United States Atomic Energy Commission funded nuclear weapon programs.

The earliest known depiction of the airfield was on the July 1970 Air Force Tactical Pilotage Chart. The 1982 Aircraft Owners and Pilots Association Airport Directory described the Tonopah Test Range airfield as having a single 6,600 ft (2,012 m) paved runway.

Operation Rolling Thunder in March 1965 led the North Vietnamese Air Force to introduce the subsonic MiG-17 (J5) and the supersonic MiG-21 to the Vietnam War, pitting them against U.S. aircraft. The MiG-21 posed a major threat to Israeli Air Defenses as well as to American pilots, so the US loaned a MiG-21 that Israel had acquired, and evaluated it in a series of test flights known as Have Doughnut. A similar program was carried out with MiG-17s under the codes Have Drill and Have Ferry.

By June 1969, the results of the evaluations of the MiG-21 and MiG-17s were incorporated into the USAF Fighter Weapons School and the Navy TOPGUN training school, and aggressor squadrons were formed there to train pilots in mock dogfights. In May 1973, Project Have Idea was initiated for joint technical and tactical evaluation of Soviet aircraft types, and took over the older Have Doughnut, Have Drill, and Have Ferry projects. It was undertaken by Detachment 1, 57th Fighter Weapons Wing. In July 1975, the 4477th Tactical Evaluation Flight (4477th TEF) was formed at Nellis AFB as a tactical evaluation organization and aggressor squadron under the 57th Fighter Weapons Wing.

Sales of United States fighter aircraft to Indonesia and Egypt in the mid-1970s to replace the Soviet fighter aircraft allowed these nations to covertly transfer unneeded MiG-21 and newer MiG-23 aircraft to the United States for evaluation. Up to 25 of these Soviet aircraft made their way to Groom Lake and pilots assigned to Detachment 1, 57th FWW at Nellis were sent to the facility for training as pilots for aggressor squadrons. However, by the mid-1970s, as the fleet of Soviet aircraft grew at Groom Lake it became crowded and a new classified facility was needed.