The Gemini-Titan II was a modified version of the Titan II intercontinental ballistic missile used as the launch vehicle for the Gemini Project. In order for the Titan II to be man-rated a number of safety systems had to be added, including a malfunction detection system to warn the crew of any failure in the rocket's equipment, backup electrical and hydraulic systems, and monitoring devices to check the rocket before launch and provide telemetry about vehicle performance during flight. In the event of an emergency, the only mode of escape for the crew was by ejection seat.