Ohio-class submarine of the United States Navy 

Ohio-class submarine of the United States Navy

The Ohio class is a class of nuclear-powered submarines used by the United States Navy. The Navy has 18 Ohio-class ballistic missile submarines (SSBN) and guided missile submarines (SSGN). The Ohio class, the largest submarines ever built for the U.S., is named after the lead submarine of this class, USS Ohio.  They were designed specifically for extended war-deterrence patrols. Each of these submarines is provided with two complete crews, called the Blue crew and the Gold crew, with each crew serving typically on 70- to 90-day deterrent patrols.