Helicopter Sikorsky HRS-1 Serial 55-069 Register N74125J N74125 127831 used by US Marine Corps USMC. Built 1951. Aircraft history and location Aircraft History 127831 US Marine Corps 1951-09-26Sikorsky S-55 c/n 55-069, ff:? del USMC as HRS-1, 127831, 26Sep51 N74125 - ex 127831 N74125J - ex N74125 Send Updates Use APP to upload photo @ (optional) When Now? / / Send