U.S. Air Force Pararescuemen assigned to the 48th Rescue Squadron Davis-Monthan Air Force Base, Ariz., go over coordinates and altitude calculations in preparation for their static line drops during Angel Thunder 2011 on Oct. 15. Approximately 1,400 U.S. military, federal and state employees and Coalition Forces are participating in the 6th Annual Angel Thunder Exercise. Angel Thunder is the world's largest military search and rescue exercise in the world.