Helicopter Sikorsky S-55 Serial 55-671 Register used by Mitsubishi (Mitsubishi Heavy Industries). Built 1954. Aircraft history and location Aircraft History n/a Mitsubishi 1954-02-01Sikorsky S-55, c/n 55-671 del Mitsubishi, 01Feb54. Send Updates Use APP to upload photo @ (optional) When Now? / / Send