The XB‑70 Valkyrie: America’s Supersonic Dream

In the mid-1950s the U.S. Air Force started a program codenamed Weapon System 110A. The goal was audacious - to build a strategic bomber that could outrun Soviet interceptors by flying higher and faster than any aircraft before it. The specification called for a range of roughly 11,000 km, an operational altitude of 21 km, and a cruising speed around Mach 3 (about 3,700 km/h).

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