Helicopter Sikorsky H-37A Mojave Serial 56-039 Register 55-613 used by US Army Aviation Army. Built 1957. Aircraft history and location Aircraft History 55-613 US Army Aviation 1957-08-07Sikorsky S-56, c/n 56-039, ff:? del US ARMY as H-37A, 55-613, 07Aug57 redesig CH-37A, Oct 62 conv CH-37B, unk wfu & soc unk. Send Updates Use APP to upload photo @ (optional) When Now? / / Send