MOUNT PLEASANT -- The aircraft carrier Yorktown played a heroic role in numerous battles for the Navy, from the time it was built in the 1940s until it was decommissioned in 1970. But as the longtime centerpiece of the floating maritime museum at Patriots Point, the inactive warship has been slowly losing a silent, corrosive and very costly war with nature. Officials at the military attraction estimated Tuesday that it would cost more than $100 million to dry dock and repair the ship's deteriorating steel hull. It's money that South Carolina does not have. Patriots Point USS Yorktown naval museums