Helicopter Sikorsky H-19D Chickasaw Serial 55-1270 Register 57-5971 used by US Army Aviation Army. Built 1959. Aircraft history and location Aircraft History 57-5971 US Army Aviation 1959-03-17Sikorsky S-55 c/n 55-1270, ff:? del US Army as H-19D, 57-5971, 17Mar59. Send Updates Use APP to upload photo @ (optional) When Now? / / Send