The Flying Dorito
The Pentagon decided to fund this plane in the 1980s, and it was one of the most horrible investments they could have made. Its radar systems were not reliable, and its use of composite materials was nothing to brag about. When the Department of Defense found out that each plane was projected to cost $165 million in 1991, Dick Cheney put an end to it.
XB 15
The XB 15 was the largest U.S. plane created until the Spruce Goose came along. The plane was so big that it had capabilities of hiding passengers inside. Sadly, in 1937 no company was making engines powerful enough for this, so the plane couldn’t reach any higher than 200 miles per hour. The U.S. Army canceled the plans for this plane, and it was only ever used in World War II as a cargo plane.