Helicopter Sikorsky HO4S-3 Serial 55-651 Register 138583 used by US Navy USN. Built 1954. Aircraft history and location Aircraft History 138583 US Navy 1954-02-02Sikorsky S-55 c/n 55-651, ff:? del USN as HO4S-3, 138583, 02Feb54. Send Updates Use APP to upload photo @ (optional) When Now? / / Send