The helicopter HUP-1 has been developed by the Piasecki company 1948. Parallel with the serial production the new modification HUP-2 was developed with more powerful engine R-975-42 and autopilot. The US NAVY has purchased 165 helicopters HUP-2, another 15 machines were transferred to French NAVY. The helicopters were used to transport cargo and passengers, and also performed the rescuing functions.