Hull maintenance technician Petty Officer 2nd Class Troy Holling operates a Naval Firefighter's Thermal Imager in the aft galley during a nuclear power mobile training team drill aboard the Nimitz-class aircraft carrier USS Ronald Reagan. NPMTT drills are conducted frequently to maintain the operational skill level and knowledge of Reactor Department personnel during an emergency. The Ronald Reagan Carrier Strike Group is on a routine deployment in the 7th Fleet area of responsibility. Operating in the Western Pacific and Indian oceans, the U.S. 7th Fleet is the largest of the forward-deployed U.S. fleets covering 52 million square miles, with approximately 50 ships, 120 aircraft and 20,000 Sailors and Marines assigned at any given time.