FAIRCHILD AIR FORCE BASE, Wash. -- Staff Sgt. Matthew Zimmer, Survival, Evasion, Resistance, and Escape specialist and water survival instructor, works to pump out as many push-ups as possible during the SERE Challenge June 13. Physical fitness was one event the participants competed in. The challenge was open to all Guardian Angel Weapon System personnel, which includes SERE specialists, combat rescue officers and pararescuemen. Sergeant Zimmer and Staff Sergeant Michael Garcia, also a SERE instructor and water survival specialist, were the winners of SERE Challenge. (U.S. Air Force photo/Staff Sgt. Matthew Rosine)