The AD-1, a one-off NASA plane explored the promise of reconfigurable wings for supersonic aircraft. It wasn’t a complete failure, though none were produced. Photo courtesy of NASA
The P-51 Mustang is almost universally regarded as the best fighter to emerge from World War II. Talk to Bob Hoover, Chuck Yeager, Bud Anderson or any of a hundred other military test pilots, and they’ll tell you the airplane was nothing less than a stroke of genius when it was introduced in 1942.