The fast attack submarine USS Tucson (SSN 770) transits past the mouth of Apra Harbor, Guam. Tucson has retractable bow planes to give the vessel increased maneuverability. Its stealth design, endurance, and mobility allow Tucson the ability to operate in oceans worldwide. Tucson is homeported in Pearl Harbor, HI. U.S. Navy photo by Photographer?s Mate 2nd Class Alan D. Monyelle.