Defenders Challenge tests defender's skills
U.S. Air Force Senior Airman Ernest Bowen, 18th Security Forces Squadron response force member, launches a simulated grenade on Kadena Air Base, Japan, May 14, 2013. Bowen participated in the 2013 Defenders Challenge, an event that challenges participants to run through an obstacle course to test their physical and mental ability as well as vital teamwork skills, to complete the course. (U.S. Air Force photo by Airman 1st Class Keith A. James/Released)