Petty Officer 2nd Class Daniel M. Caraballoa (left), a machinery technician assigned to Coast Guard Maritime Forces Protection Unit Bangor in Silverdale, Wash., explains how to operate a 64-foot Special Purpose Craft -- Screening Vessel to Christopher Marten, a Washington state resident with exceptional needs, while underway in Hood Canal, July 9, 2014. The SPC-SV, a Navy-owned vessel operated by Coast Guard crews, is used to escort submarines to and from Naval Base Kitsap-Bangor. (U.S. Coast Guard photo by Petty Officer 3rd Class Katelyn Shearer)