The Christmas Bullet
Dr. William Whitney Christmas, a known psychopath first created the Christmas Bullet. When he made this plane he knew that the first round would end up with the pilot dying after hitting a certain altitude. He brought in Cuthbert Mills to test out the plane. He and his mom went to go fly the plane, but the wings folded in during take-off and then crashed.
The Messerschmitt Me 163 Komet
This plane was actually made as a rocket-powered interceptor to attack enemy planes. The Messerschmitt Me 163 Komet could go from 0 to 100 miles per hour faster than any other competitor. Sadly, it had a very small fuel tank and could only stay in the air for around three minutes. Many pilots died in the process as it was constantly leaking or creating fires.