Helicopter Sikorsky H-19B Chickasaw Serial 55-731 Register 52-7584 used by US Air Force USAF. Built 1954. Aircraft history and location Aircraft History 52-7584 US Air Force 1954-06-16Sikorsky S-55 c/n 55-731, ff:? del USAF as H-19B, 52-7584, 16Jun54. Send Updates Use APP to upload photo @ (optional) When Now? / / Send