Helicopter Sikorsky H-19B Chickasaw Serial 55-635 Register 52-7532 used by US Air Force USAF. Built 1954. Aircraft history and location Aircraft History 52-7532 US Air Force 1954-03-02Sikorsky S-55 c/n 55-635, ff:? del USAF as H-19B, 52-7532, 02Mar54. Send Updates Use APP to upload photo @ (optional) When Now? / / Send