Helicopter Sikorsky H-19D Chickasaw Serial 55-1254 Register 57-5956 used by US Army Aviation Army. Built 1958. Aircraft history and location Aircraft History 57-5956 US Army Aviation 1958-12-23Sikorsky S-55 c/n 55-1254, ff:? del US Army as H-19D, 57-5956, 23Dec58. Send Updates Use APP to upload photo @ (optional) When Now? / / Send