Helicopter Sikorsky S-55 Serial 55-758 Register HS-4 used by Royal Thai Air Force. Built 1954. Aircraft history and location Aircraft History For HS-4 see also mi-8t 133 04 HS-4 Royal Thai Air Force 1954-08-17Sikorsky S-55 c/n 55-758, ff:? del RTAF as HS-4, 17Aug54 asgd 63 Sqn, 6th Wing, Royal Thai Air Force, reser: 63??. HS3-4/97 Send Updates Use APP to upload photo @ (optional) When Now? / / Send
