Douglas XB-42 Mixmaster
The Douglas XB-42 Mixmaster was an unconventional prototype aircraft initially developed by the company as a private project. It was only once they showed the designs to the United States Army Air Force in May 1943 that the military got involved. The USAAF ordered two prototypes and one static test airframe. The air force were sold on the design as it promised the same sort of range as the Boeing B-29 Superfortress, but didn’t come with the B-29′s massive size or cost.