Col. Bill Knight (left), 11th Wing/Joint Base Andrews commander, observes a joint-training exercise between the United States Secret Service and 811th Security Forces Squadron Protective Services on The Courses at Andrews. The two-day training was the first large-scale contingency response exercise between Joint Base Andrews and the USSS. (U.S. Air Force Photo/Staff Sgt. Robert Cloys)

Col. Bill Knight, 11th Wing/Joint Base Andrews commander (right), discusses a training scenario with United States Secret Service Special Agent Rob Donahue (left) and Major Aaron Rittgers (middle), 811th Security Forces Squadron commander, on The Courses at Andrews. The two-day training was the first large-scale contingency response exercise between Joint Base Andrews and the USSS. (U.S. Air Force Photo/Staff Sgt. Robert Cloys)

Members of 811th Security Forces Squadron Protective Services listen to a training scenario recap during a contingency response exercise held by Joint Base Andrews and the United States Secret Service. (U.S. Air Force Photo/Staff Sgt. Robert Cloys)

Tech. Sgt. Frank Sabella (right), 811th Security Forces Squadron Protective Services element leader, briefs United States Secret Service Special Agent Ed Sebring (left) after a training scenario on the Joint Base Andrews flight line. The two-day training was the first large-scale contingency response exercise between Joint Base Andrews and the USSS. (U.S. Air Force Photo/Staff Sgt. Robert Cloys)