The cavernous hangar bay of USS Carl Vinson is illuminated by red lights during ?darken ship? as flight operations conclude for the day. ?Darken ship? is a security measure used to reduce visibility of the ship. Because light is visible from miles away, darken ship is observed by those topside and involves the elimination of any type of light. Topside doors and hatches are closed, ports are blacked out, smoking is forbidden. During darken ship, flashlights or lanterns with red lens covers can be used if necessary. Carl Vinson is underway off the west coast training in preparation for an upcoming routine deployment. U.S. Navy photo by Photographer's Mate Airman Chris M. Valdez.