The war plane with no weapons not only had the lines of a spaceship, it set the record for the fastest air-breathing manned aircraft in 1976 – a record that remains unchallenged to this day. So how was it built, and what was it like to fly this supersonic denizen of the edge of space?

Developed by Lockheed at its famously secretive Skunk Works in Burbank, California, the SR-71 was a derivative of the A-12 reconnaissance plane built for the CIA as a replacement for the U2 spy plane of the 1950s. It was the brainchild of American aerospace engineer Clarence "Kelly" Johnson who, like a real-life Tony Stark, came up with all sorts of remarkable design innovations that pushed forward aerospace engineering. 

The SR-71 was built for the US Air Force and operated from 1964 to 1998. The Blackbird, or Habu, as it was also nicknamed after a venomous Japanese snake, could outrun any plane or missile that was sent against it. It set multiple speed and altitude records that have yet to be matched and was one of the first stealth aircraft. It also became stronger as it grew older, despite the fact that it was built by engineers using slide rules. That's a bit like prying open your smartphone and finding a little man inside with an abacus.