Photo: Post Independence Day FOD walk Published July 6, 2010 By Master Sgt. Dave Neve 162nd Fighter Wing Public Affairs TUCSON, Ariz. -- Nearly 100 Arizona Air National Guardsmen walk the flightline here July 6 in search of Foreign Object Damage, or FOD. Small rocks and loose screws are the usual culprits when aircraft maintainers encounter FOD, but after Independence Day a massive FOD walk was needed to find debris from fireworks and celebratory fire. As a result of this early-morning mass FOD walk, four bullets were found near the F-16 Fighting Falcons parked at Tucson International Airport. Since foreign objects are easily drawn into the fighter jet's air intake, the walk saved up to four engines. Each F-16 engine costs about $1.3 million. (Air Force photo by Master Sgt. Dave Neve)