U.S. Air Force and naval aircraft fly over the USS Abraham Lincoln (CVN 72), USS Kitty Hawk (CV 63) and USS Ronald Reagan (CVN 76) carrier strike groups in the Philippine Sea June 18, 2006, during exercise Valiant Shield 2006. The joint exercise consists of 28 naval vessels, more than 300 aircraft, and approximately 20,000 service members from the Navy, Army, Air Force, Marine Corps and Coast Guard. www.defenselink.mil