The HC-2 was followed by the HC-3, which was an enlarged four-seater based on the HC-2 but with a four-leg undercarriage, englarged cabin section and an M-108H engine mounted above and behind the cabin. Three prototypes were tested (OK-15 to OK-17) but the type did not reach production.

R.Simpson "Airlife's Helicopter and Rotorcraft", 1998