Defenders welcome new commander Published June 29, 2015 By Senior Airman Jason Wiese 90th Missile Wing Public Affairs F.E. WARREN AIR FORCE BASE, Wyo. -- Col. Christopher Corley received command of the 90th Security Forces Group during a change of command here June 29, 2015. A change of command ceremony is a tradition that represents a formal transfer of authority and responsibility from the outgoing commander to the incoming commander. Col. Craig Allton, outgoing commander, retired from the U.S. Air Force later on the same day.