At the height of the Cold War, the United States came up with the ultimate strategic bomber. This was the North American XB-70 Valkyrie. The XB-70 was a Mach 3 prototype that would have led to the ...

-Engineered to "ride" its own shockwave for fuel efficiency, the massive bomber was a technological masterpiece. However, its development coincided with the dawn of the "missile age." -The rise of ...