Antonov A-40 Flying Tank
Originally, this plane was designed to supply troops with tanks and was designed with the capability to attach a glider towed by a Russian TB-3 bomber. Unfortunately, it only lasted one test before the plane overheated due to the weight and drag everything brought along with it. After the tank failed its mission, it was driven on the ground back to base.
Antonov A-40 Flying Tank
Bonney Gull
In 1928 American pilot and inventor Leonard Bonney decided that he wanted to test out a new kind of airplane wing. Fixed-wing aviation had been running successfully for quite some time now, so he decided to test a sort of bird wing replication. The wings on the plane did not flap like a bird’s, but they were curved like a gull’s wings. It lasted only one flight and crashed right after takeoff.
Bonney Gull