Birmingham, Alabama D-21B #539 – Beale Air Force Base, near Marysville, California Specifications (Lockheed D-21) D-21 and D-21B without booster Wingspan: Length: Height: Launch weight: Cruise speed: Mach 3.32 (2,524 mph; 4062 km/h) Maximum speed: (conversions estimated at the service ceiling altitude) Service ceiling: Range: Engine: 1 x Marquardt RJ43-MA-20S4 ramjet, Sources: Pace, Landis & Jenkins, Donald See also References Citations Bibliography External links Loss of M-21 and D-21, including video of successful launches and the midair collision Directory of U.S. Military Rockets and Missiles Weapons of Precise Destruction Photos of Lockheed D-21B No. 527 in China Aviation Museum, Beijing D-021 1960s United States military reconnaissance aircraft Unmanned military aircraft of the United States Single-engined jet aircraft Ramjet-powered aircraft Tailless delta-wing aircraft Unmanned stealth aircraft Composite aircraft Aircraft first flown in 1964