Clifton Curtis 'C.C.' Williams (September 26, 1932 - October 5, 1967) was a NASA astronaut and United States Marine Corps Major (United States) who was killed after a mechanical failure caused the flight controls in a T-38 he was piloting to stop responding. The aircraft crashed in Florida near Tallahassee.
He was an associate member of the Society of Experimental Test Pilots and member of Pi Tau Sigma (national mechanical honorary, and Tau Beta Pi (national engineering society). He was married to Beth Lansche Williams and had two children, Catherine and Jane Dee.
Williams served on the backup crew for Gemini X and had been assigned to the back-up crew for what would be the Apollo 9 mission. This crew placement would have most likely led to an assignment as Lunar Module pilot for Apollo 12. After his death, he was replaced on the Apollo 9 backup crew by Alan Bean who had been his commander on the Gemini X backup crew.
In the 1998 miniseries From the Earth to the Moon, Williams was played by Jim Leavy.
The Apollo 12 mission patch has four stars on it - one each for the three astronauts who flew the mission, and one for Williams. Williams is buried in Arlington National Cemetery.