Clifton Williams

Astronaut Clifton Williams was killed on October 5, 1967 after a mechanical failure caused his controls to stop responding. He had been assigned to the back-up crew for what would be the Apollo 9 mission and would have most likely been assigned as Lunar Module pilot for Apollo 12. The Apollo 12 mission patch has four stars on it - one each for the three astronauts who flew the mission, and one for Williams.