PZL Swidnik SM-4


Three-seat helicopter with enclosed cabin, open-frame rear fuselage, skid u/c, GRP main rotor and one 180hp Narkiewicz WN-6S six-cylinder horizontally-opposed air-cooled piston engine mounted at an angle behind cabin section. The only prototype of SM-4 Latka (Latka) was built in 1962 and ground-tested, but was not flown, because its prototype engine 180 hp WN-6S was not fully tested and not approved for flight.