Helicopter Sikorsky HO4S-3 Serial 55-652 Register 138584 used by US Navy USN. Built 1954. Aircraft history and location Aircraft History 138584 US Navy 1954-02-02Sikorsky S-55 c/n 55-652, ff:? del USN as HO4S-3, 138584, 02Feb54. Send Updates Use APP to upload photo @ (optional) When Now? / / Send