At the time of the Cold War, Russia had nothing that could shoot the U2 out of the sky. Even their MiG jets had a ceiling 10,000 feet below the U2's gliding altitude.
One pilot said they'd buzz around below him, "like angry bees."
When the U-2 "Dragon Lady" debuted in 1957 it was an astonishing piece of technological achievement.
Able to fly reconnaissance from more than 13-miles above the earth, gather data through all weather conditions any time of day or night, while staying beyond the reach of Soviet military — it was an unbelievable achievement.
(Special thanks to the guys at Airmen magazine for the great imagery.)
When you plan on scraping the edge of space, you have to wear a space suit
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At it's top altitude, if the spy plane's engine went down, it could glide more than 250 miles
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Pilots were required to keep the bird in a five knot speed window
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See the rest of the story at Business Insider