A U.S. Air Force F-22 Raptor taxies into the Kentucky Air National Guard Base in Louisville, Ky., on April 14, 2011, in preparation for the Thunder Over Louisville air show. The Raptors will be one of show?s marquee events when Thunder takes place over the Ohio River on April 16. Nearly 60 aircraft are expected to participate in Thunder. (U.S. Air Force photo by Maj. Dale Greer)