Frank Lee Culbertson Jr. is an American former naval officer and aviator, test pilot, aerospace engineer, NASA astronaut, graduate of the US Naval Academy, and member of the United States Astronaut Hall of Fame. He served as the Commander of the International Space Station for almost four months in 2001 and was the only U.S. citizen not on Earth when the September 11 attacks occurred.
Culbertson retired as President of the Space Systems Group at Northrop Grumman Innovation Systems, where he was responsible for the execution, business development, and financial performance of the company's human spaceflight, science, commercial communications, and national security satellite activities, as well as technical services to various government customers. These include some of Northrop Grumman's largest programs such as NASA's Commercial Resupply Services initiatives to the International Space Station as well as various national security-related programs.