In A Nutshell
Well, gliding tank.
A momentous event occurred in September 1942—the only flight of the Soviet Antonov-A40 glider “aircraft,” which was, for all intents and purposes, a tank with wings. Defying physics and common sense, the contraption was able glide to a smooth landing, but the project was discontinued shortly thereafter.
Note: The picture above is of a designer’s model, not the full-size version.
The Whole Bushel
It might seem ludicrous now, but in the 1930s and throughout World War II, many countries were intrigued by the idea of a flying tank and other ways to deploy armored units aerially. The British tested a one-third scale model of a winged tank, some Japanese experimental designs existed, and renowned engineer J. Walter Christie (whose suspension system vastly improved cross-country tank speeds) offered a prototype to the US military. Christie had big plans, too, proclaiming “the flying tank is a machine to end war,” but his abrasive personality meant he got nowhere.
The Soviets, however, went further. They came up with many possible solutions for deploying armored units aerially—strapping light tanks to the bottom of heavy bombers and landing them on airfields, parachuting them, and dropping amphibious tanks into water. These were found to be unsatisfactory, largely because the crew had to be brought in separately, so they commissioned Oleg Antonov to design a glider capable of carrying a tank. Antonov went one step further and strapped biplane wings (and a tail) to a T-60 tank.
This allowed the (presumably very brave) crew to reach the battlefield inside their vehicle, though you would think the removal of armaments, ammunition, headlights and even a good amount of the fuel might cancel out this advantage. Despite being stripped down to the barest of essentials, the weight and drag of the tank proved too great for the towing aircraft, which was unable to maintain the necessary speed of 160 kilometers per hour (100 mph) and consequently released it earlier than planned.
After release, however, the tank glided smoothly, landed in a field, detached its wings and tail, and was calmly driven back to base (with what little fuel it did carry). Unfortunately, due to the lack of an appropriate tow aircraft and the fact that the Germans were currently fighting their way through Russia, the Antonov was abandoned in favor of things more beneficial to the Russian war effort.
Show Me The Proof
Silent Skies: Gliders at War 1939-1945, by Tim Lynch
Edison’s Concrete Piano, by Judy Wearing
War History Online: WWII Flying Tank
Unreal Aircraft: Roadable Aircraft—Antonov KT Flying Tank