Bryan O'Connor contributed to the safety practices established by NASA following the 1986 shuttle Challenger tragedy. Photo Credit/NASA photo

NASA safety chief Bryan O’Connor, a former astronaut, announced his retirement on Tuesday, the first high ranking space agency official to depart in the aftermath of the shuttle program’s retirement.

The two time shuttle commander and pilot will depart Aug. 31.

“Even though good practice suggests shorter tours for senior leaders, I did not want to pass the safety baton until after the STS-135 crew left Atlantis on the runway,” said O’Connor, who has filled the Washington post for nine years, “This transition is a great time to let someone new take on this wonderful role you’ve permitted me to serve in.”

 Atlantis and her four person crew touched down last Thursday at NASA’s Kennedy Space Center, bringing to a close the three-decade, 135 mission shuttle program.

 “I am deeply grateful for his vigilance over the safety and well-being of NASA’s people and its work,” said NASA Administrator Charles Bolden, who shared a long association with O’Connor. “His concern and commitment have encompassed not just the space shuttle and the astronaut corps, but every mission, large or small, and every member of the NASA family. He’ll be sorely missed.”

The agency has not announced a replacement. O’Connor was selected for astronaut training in 1980, while a Marine Corps test pilot.

He piloted a 1985 mission that deployed multiple communications satellites and served as commander of a 1991 mission dedicated to lift sciences research.

 O’Connor was instrumental in negotiating a series of cooperative NASA shuttle missions to Russia’s Mir Space Station and served as the director of a critical re-design of the International Space Station in 1993.

 O’Connor left NASA in 1996 to become an aerospace consultant and executive. He returned to the agency in mid-2002 to serve in Washington as Chief of Safety and Mission Assurance.