While a CH-46 Sea Knight lifts off behind him, Lance Cpl. Charles E. Weber, a radio operator with the 3rd Low Altitude Air Defense Battalion, guards the perimeter a makeshift landing zone at Centennial Middle School in Yuma, Ariz., during an exercise simulating the evacuation of U.S. citizens from a foreign nation in crisis April 17, 2009. For special exercises throughout the year, the city of Yuma allows the Marine Corps to use local parks and school sports fields as training areas, which provide real urban locales that couldn't easily be simulated. During the exercise, numerous CH-46s and CH-53 Sea Stallion helicopters quickly landed and launched again, dropping off Marines and rescuing role players. The exercise was part of the latest Weapons and Tactics Instructors course taught by the Marine Aviation Weapons and Tactics Squadron 1, based at the Marine Corps Air Station in Yuma. The course teaches Marine aviators and other support personnel from across the Corps the latest in air tactics so students can graduate as instructors who develop future training for their units. Weber is a 20-year-old native of Schwenksville, Pa.