The #Lockheed #SR_71 was an advanced, long-range, #Mach_3 strategic reconnaissance aircraft developed from the Lockheed A-12 and YF-12A aircraft by the Lockheed Skunk Works. The SR-71 was unofficially named the #Blackbird, and called the Habu by its crews. Clarence "Kelly" Johnson was responsible for many of the design's innovative concepts. A defensive feature of the aircraft was its high speed and operating altitude, whereby, if a surface-to-air #missile launch were detected, standard #evasive