Helicopter Sikorsky H-19D Chickasaw Serial 55-1241 Register 57-1641 used by US Army Aviation Army. Built 1958. Aircraft history and location Aircraft History 57-1641 US Army Aviation 1958-11-06Sikorsky S-55 c/n 55-1241, ff:? del US Army as H-19D, 57-1641, 06Nov58. Send Updates Use APP to upload photo @ (optional) When Now? / / Send