Helicopter Sikorsky HO5S-1 Serial 52-019 Register N4645S 125526 used by US Marine Corps USMC. Built 1952. Aircraft history and location Aircraft History 125526 US Marine Corps 1952-04-30Sikorsky S-52-3, c/n 52-019, ff:? acc BuAerRep (BAR) East Hartford, CT, 30Apr52 del USMC as HO5S-1, 125526, 26May52 wfu & sold VAT as S-52-3, N4645S, unk. 1956-08-17soc 17aug56 N4645S - 1972-04 A KOPF1972 at Opa Locka Send Updates Use APP to upload photo @ (optional) When Now? / / Send