In 1971 the Soviets commissioned the Kamov Design Bureau to develop a one-man, collapsible helicopter to fit into a 500mm torpedo tube and be assembled in 15 minutes. The result was the KA-56, and it almost worked.
We can just imagine how the action plays out; A spy, deep in enemy territory gets into a tight spot, he needs an extraction but there are no resources in the area so he calls in a KA-56 drop. The stealth submarine off the coast in international waters receives the call and fires off a surface to air missile containing not a weapons payload but a one man-helicopter folded up inside the body of the projectile. It pops a parachute directly over the spy's location and gently touches down, fifteen minutes later he's put it all together and makes the daring escape.
Sounds like something out of a James Bond flick, but it was and actual project handed to Deputy Chief Designer Sergei Fomin of the Kamaz helicopter company in 1971. The program was a pie-in-the-sky look at just how small you could get rotary wing aircraft, and how you could transport them most effectively. Fomin and his team constructed a several full-scale mock-up to work out the mechanical origami necessary to build such a machine and ended up with the KA-56"Wasp."
The Wasp was specified with a folding body in one side of its 500mm transport case and the twin-rotor blades strapped into the other side. Assembly didn't take fifteen minutes, it could be done in ten by folding the mast upright, fixing the wheels in place, folding the tail down and then bolting the rotors onto the output shaft. The design was so close to working, but the problem was the powerplant. It required a 40 hp, air-cooled rotary engine, and despite the best efforts of the engineers on the project they couldn't source or design one within the size envelope of the Wasp. Pity too, this could've been one of those military gadgets that filters down to the general population. We could all be flying personal helicopters these days and folding them up under the porch at night.