An Airman from Nellis Air Force Base, Nev., runs to safety after a simulated plane crash during the 2012 Triennial Emergency Preparedness Exercise conducted by the Clark County Department of Aviation at McCarran International Airport Oct. 24, 2012, in Las Vegas, Nev. This realistic exercise helps provide police, fire and ambulance agencies the opportunity to participate in a mass casualty exercise for emergency response training and evaluations. (U.S. Air Force photo by Senior Airman Daniel Hughes)