Detailed history and photos of helicopter Sikorsky HRS-3 Serial 55-447 Register 137838 used by US Navy USN Track service timeline and current status. Aircraft History 137838 US Navy 1953-06-11Sikorsky S-55 c/n 55-447, ff:? del USN as HRS-3, 137838, 11Jun53. Send Updates Use APP to upload photo @ (optional) When Now? / / Send
