The Soviet Kamov KA-56 folding helicopter. I don't believe it ever flew; these photos are of a full-scale mockup. Designed to be able to be launched out of a submarine's torpedo tube, and assembled in 15 minutes.
More: Kamov Ka-56 folding helicopter
Helicopter rescue basket spins uncontrollably - GIF
1922 helicopter prototype - GIF
Marine helicopter towing fail - video