Great Planes looks into the stories behind the most influential, innovative and intriguing machines that ever took flight. The North American Aviation XB-70 Valkyrie was the prototype version of the proposed B-70 nuclear-armed deep penetration bomber for the United States Air Force's Strategic Air Command. Designed in the late 1950s, the Valkyrie was a large six-engined aircraft able to fly Mach 3+ at an altitude of 70,000 ft (21,000 m), which would have allowed it to avoid interceptors, the only effective anti-bomber weapon at the time. Engineers had tried to build a supersonic bomber since World War II, and finally completed the XB-70 Valkyrie in 1964. See the story of this amazing plane on this episode of Wings.
Alexander IV History's supplementary notes:
Narrated by: Ron David
First flight: 21 September 1964
Retired: 4 February 1969
https://en.wikipedia.org/wiki/North_American_XB-70_Valkyrie
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