Mil V-7
The Mil V-7 was an experimental four-seat helicopter with AI-7 ramjets at the tips of the two rotor blades. It had an egg-shaped fuselage, skid undercarriage, and a two-bladed tail rotor on a short tubular tail boom. Four aircraft were built in the late 1950s, but only one is known to have flown, with only the pilot aboard.