The 6 Most Expensive Supersonic Planes Ever Built
Key Points Supersonic planes are airplanes that can fly at supersonic speeds. This means they travel faster than the speed of sound, or Mach number 1. Supersonic planes were invented in the second half of the twentieth century for military and research purposes. The Concorde was the most expensive supersonic plane ever built, at 2.8 billion. Since the Wright brothers’ success at Kitty Hawk, North Carolina, in 1903, humans have been obsessed with the speed of airplanes for travel and defense....