Helicopter Sikorsky HR2S-1 Serial 56-107 Register 145869 used by US Marine Corps USMC. Built 1958. Aircraft history and location Aircraft History 145869 US Marine Corps 1958-10-31Sikorsky S-56, c/n 56-107, ff:? del USMC as HR2S-1, 145869, 31Oct58 wfu & soc unk. 1968-04-30soc 30apr68 Send Updates Use APP to upload photo @ (optional) When Now? / / Send