In 1971, two aeronautical engineering students set out to make an aircraft by mating the wings, engine, and airframe of a Cessna Skymaster to a modified Ford Pinto. In principle you could drive to the airport, attach the wings in two minutes, and get quickly into the air under the combined power of two engines. At your destination you’d land, stop quickly using the car’s four-wheel brakes, detach the wings, and drive off.
By 1973, two prototypes had been built and the FAA was considering certification, but on two testing flights a wing strut detached from the car. One pilot had to land in a bean field, and another died when the wing folded. The project was dropped.