Under the title of the A-12, the SR-71 Blackbird
started being
conceptualized back in the late 1950's, by the famed Skunk Works, which
also developed the F117 Stealth fighter, and YF-22/23 fighters along with
several other classified aircraft. The A12 which was originally designed
for the CIA was 3 feet short of the SR-71's 101 feet in length and capable
Mach 3.4+.
Click on the following for some larger pics:
