Helicopter Sikorsky H-19D Chickasaw Serial 55-1160 Register 56-4273 used by US Army Aviation Army. Built 1958. Aircraft history and location Aircraft History 56-4273 US Army Aviation 1958-01-28Sikorsky S-55 c/n 55-1160, ff:? del US Army as H-19D, 56-4273, 28Jan58. Send Updates Use APP to upload photo @ (optional) When Now? / / Send