Navy Lt. John Knolla mans the tactical action officer watch in the combat direction center aboard the Nimitz-class aircraft carrier USS Ronald Reagan during Exercise Valiant Shield 2006 in the Philippine Sea. Valiant Shield focuses on integrated joint training among U.S. military forces, enabling real-world proficiency in sustaining joint forces and in detecting, locating, tracking and engaging units at sea, in the air, on land and in cyberspace in response to a range of mission areas. U.S. Navy photo by Airman Christine Singh Navy Lt. John Knolla mans the tactical action officer watch in the combat direction center aboard the Nimitz-class aircraft carrier USS Ronald Reagan during Exercise Valiant Shield 2006 in the Philippine Sea. Valiant Shield focuses on integrated joint training among U.S. military forces, enabling real-world proficiency in sustaining joint forces and in detecting, locating, tracking and engaging units at sea, in the air, on land and in cyberspace in response to a range of mission areas. U.S. Navy photo by Airman Christine Singh SHARE: Download: Full Size (0.87 MB) Credit: VIRIN: 296162-D-VHR79-257.jpg Photo Gallery