Helicopter Sikorsky H-19B Chickasaw Serial 55-676 Register 52-7557 used by US Air Force USAF. Built 1954. Aircraft history and location Aircraft History 52-7557 US Air Force 1954-04-02Sikorsky S-55 c/n 55-676, ff:? del USAF as H-19B, 52-7557, 02Apr54. Send Updates Use APP to upload photo @ (optional) When Now? / / Send