21st SFS new commander
PETERSON AIR FORCE BASE, Colo. – Lt. Col. Sean Tiernan accepts the 21st Security Forces Squadron flag from Col. Kimerlee Conner, 21st Mission Support Group commander, and assumes command of the 21st SFS June 25, 2012. Tiernan comes to Peterson AFB from Air Force Central Command at Shaw Air Force Base, S.C. The 21st SFS maintains the second-largest working dog kennel in the United States and deploys combat-ready Airmen worldwide. (U.S. Air Force photo/Craig Denton)