Lockheed M-21

Lockheed M-21. The Lockheed M-21 was a specialized variant of the Lockheed A-12 high-altitude reconnaissance aircraft, developed by the Lockheed Corporation's secret Skunk Works division. Designed as a "mother ship" to launch the Lockheed D-21 supersonic reconnaissance drone, the M-21 program was a highly classified element of Cold War aerial espionage. The project was ultimately short-lived, with operations ceasing after a fatal mid-air collision during a launch test in 1966.

Development and design

The M-21's development was spearheaded by Lockheed's legendary designer Clarence "Kelly" Johnson under the Skunk Works project codenamed Project Tagboard. It was created as a dedicated launch platform for the D-21 drone, an autonomous, ramjet-powered reconnaissance vehicle intended for overflights of denied territories like the Soviet Union and the People's Republic of China. The design involved modifying the standard Lockheed A-12 airframe by adding a second cockpit for a Launch Control Officer (LCO) behind the pilot and installing a pylon on the aircraft's spine to carry the drone. This configuration required extensive aerodynamic testing and engineering to manage the complex interactions during the high-speed, high-altitude separation of the two vehicles. The program was conducted under the utmost secrecy for the Central Intelligence Agency, with support from the United States Air Force.

Operational history

Operational testing of the M-21 and D-21 drone system began in late 1964 from Groom Lake (Area 51). The first successful captive carry flight occurred in December 1964, and the first successful separation of a drone followed in March 1966. However, the program met with disaster on 30 July 1966, during the fourth launch attempt. Following separation, the D-21 drone experienced an unstart of its Marquardt ramjet engine, causing it to pitch up and collide with the M-21 mother ship. The M-21 was severely damaged and crashed into the Pacific Ocean off the coast of California. Pilot Bill Park survived, but Launch Control Officer Ray Torick drowned after his pressure suit filled with water. This accident led to the immediate termination of the M-21 launch program. The remaining M-21 airframe was placed into storage, and the drone launch mission was subsequently transferred to modified Boeing B-52 Stratofortress bombers under the new designation D-21B.

Specifications (M-21)

General characteristics * **Crew:** 2 (Pilot and Launch Control Officer) * **Length:** 101 ft 7 in (30.96 m) * **Wingspan:** 55 ft 7 in (16.94 m) * **Height:** 18 ft 6 in (5.64 m) * **Powerplant:** 2 × Pratt & Whitney J58 continuous-bleed afterburning turbojets * **Maximum speed:** Mach 3.35 * **Service ceiling:** 90,000 ft (27,400 m) * **Armament:** None * **Avionics:** Specialized systems for drone launch control and tracking.

Variants

The primary variant was the M-21 itself, a purpose-built two-seat launch platform. The program directly led to the development of the Lockheed D-21 reconnaissance drone. Following the M-21's retirement, the drone was adapted for launch from the Boeing B-52 Stratofortress, becoming the D-21B. No other variants of the M-21 airframe were produced. The sole surviving M-21 (Article 135) is on display at the Museum of Flight in Seattle, Washington, mated with a D-21 drone.

See also

* Lockheed A-12 – The single-seat reconnaissance aircraft from which the M-21 was derived. * Lockheed SR-71 Blackbird – The better-known, two-seat strategic reconnaissance aircraft developed concurrently. * Lockheed D-21 – The unmanned reconnaissance drone launched from the M-21. * Project Tagboard – The codename for the M-21/D-21 development program. * Skunk Works – The Lockheed advanced development division responsible for the aircraft.

Category:United States reconnaissance aircraft 1960–1969 Category:Lockheed aircraft Category:Cold War reconnaissance aircraft of the United States