Colonel Hammond flew as pilot of Discovery on STS-39, the first unclassified Department of Defense mission (April 28 to May 6, 1991). He logged 199 hours and 23 minutes of space flight. Recently, he was the pilot on STS-64 aboard the Space Shuttle Discovery. Hammond was also assigned as Lead Ascent/Entry CAPCOM for missions STS-73 through STS-78. During the same period, Hammond served as the Branch Chief of the Flight Support Branch, supervising CAPCOM and ASP activities. Hammond is currently assigned as the Branch Chief of the Astronaut Office Safety Branch where he monitors all T-38, Shuttle, and Space Station safety issues.