Helicopter Sikorsky H-37A Mojave Serial 56-074 Register 55-639 used by US Army Aviation Army. Built 1958. Aircraft history and location Aircraft History 55-639 US Army Aviation 1958-03-12Sikorsky S-56, c/n 56-074, ff:? del US ARMY as H-37A, 55-639, 12Mar58 redesig CH-37A, Oct 62 conv CH-37B, unk wfu & soc unk. Send Updates Use APP to upload photo @ (optional) When Now? / / Send
