Helicopter Sikorsky HRS-1 Serial 55-051 Register 127815 used by US Marine Corps USMC. Built 1951. Aircraft history and location Aircraft History 127815 US Marine Corps 1951-08-16Sikorsky S-55 c/n 55-051, ff:? del USMC as HRS-1, 127815, 16Aug51 1957-04-10 soc 10apr57 Cherry Point Send Updates Use APP to upload photo @ (optional) When Now? / / Send