Helicopter Sikorsky HRS-1 Serial 55-071 Register 127833 used by US Marine Corps USMC. Built 1951. Aircraft history and location Aircraft History 127833 US Marine Corps 1951-11-02Sikorsky S-55 c/n 55-071, ff:? del USMC as HRS-1, 127833, 02Nov51 1958-01 wfu Jan58 GI Memphis Send Updates Use APP to upload photo @ (optional) When Now? / / Send