200316-N-CM740-1008 NEWPORT NEWS, Va. (March 16, 2020) Seaman Tiffany Roberts, left, assigned to the Nimitz-class aircraft carrier USS George Washington (CVN 73), secures a temporary ventilation shaft while Boatswain’s Mate Seaman Cristian Sanchez, right, assigned to deck department, lifts the shaft into place. George Washington is undergoing refueling complex overhaul (RCOH) at Newport News Shipyard. RCOH is a nearly four-year project performed only once during a carrier's 50-year service life that includes refueling the ship's two nuclear reactors, as well as significant repairs, upgrades, and modernization. (U.S. Navy photo by Mass Communication Specialist Seaman Robert Stamer/Released)