U.S. Air Force Senior Airman Howard Zumbrunnen, 13th Aircraft Maintenance Unit tactical maintainer, attaches safety wire to a nut on the bottom of a wing on a F-16 Fighting Falcon at Misawa Air Base, Japan, March 19, 2012. More than 70 Airmen from the 13th and 14th Fighter Squadrons and 35th Maintenance Group were flown to Paya Lebar Air Base, Singapore in support of Commando Sling, exercise that was created to help build relations with the people of Singapore and train U.S. Air Force pilots in a foreign environment. (U.S. Air Force photo/Airman 1st Class Kaleb Snay/Released)