M-21 with D-21 Drone
(SR-71 predecessor)This is the Lockheed M-21/D-21B combination - technically 'MD-21' when they are mated. Beautifully restored by the Museum of Flight in Seattle, Washington, USA at the south end of Boeing Field.
The M-21 is a two seat modification of the A-12 spy aircraft, the predecessor to the SR-71 Blackbird. Two A-12s were modified to carry the D-21 ramjet powered reconnaissance drone. The other M-21 was lost in a launching accident in the 1960s.
The images and the explaining text were kindly contributed by Bob Harrington.