U.S. Air National Guard Staff Sgt. Christopher Seward, 184th Civil Engineer Squadron water and fuel system maintenance, tests potable water for residual chlorine during Silver Flag exercise, Detachment 1, 823rd RED HORSE Squadron, Tyndall Air Force Base, Fla., Aug. 12, 2014. Silver Flag is a six-day contingency scenario that gives participants five days of training, then their knowledge is tested during a one-day mock deployment scenario to a forward operating base where they open an airfield with surrounding insurgent dangers. Airmen used a variety of combat and survival skills during the 17-hour exercise through different scenarios such as, an in-flight emergency landing, fire suppression, insurgent attacks and equipment malfunctions.