Helicopter Sikorsky XHR2S-1 Serial 56-5X Register 133735 used by US Marine Corps USMC. Built 1954. Aircraft history and location Aircraft History 133735 US Marine Corps 1954-05-28Sikorsky S-56, c/n 56-5X, ff:? del NPRO, as XHR2S-1, 133735, 28May54 retained by Sikorsky for testing, scr unk? Send Updates Use APP to upload photo @ (optional) When Now? / / Send
