The SM-2, a Polish development of the basic design was flown late in 1959. This has a longer nose, thereby enlarging the cabin to accommodate 4 passengers in addition to the pilot. In the ambulance role, the SM-2 can take a third stretcher inside the cabin in addition to the two carried on external panniers. Production of the SM-2 was initiated in 1961 to fulfil both military and civil orders.

K.Munson "Helicopters And Other Rotorcraft Since 1907", 1968

Technical data for PZL Swidnik SM-2 Engine: 1 x Lit-3 pistone engine, rated at 425kW, main rotor diameter: 14.3m, length: 17.0m, height: 3.1m, take-off weight: 2550kg, empty weight: 1934kg, max speed: 170km/h, cruising speed: 130km/h, ceiling: 3700m, range with max fuel: 550km