The U.S. Navy recently announced that it will resume allowing crews of SSBNs (ballistic missile carrying nuclear subs) some shore leave in the middle of their 77 day cruises. SSBNs have two crews, which alternate running the boats. In between each cruise the boats are in port for about 35 days for maintenance and resupply. So each crew spends about 34 percent of their time at sea. Up until 2003 the SSBNs regularly stopped at American or foreign naval bases to give the crews some time ashore and an opportunity for the sub to stock up on perishables (vegetables, fruits and the like). This was a big morale boost for the SSBN crews, who got to see a foreign country, if only briefly, and have a few drinks. The mid-cruise shore leave practice was halted because increase security concerns after 2001.
The 17,000 ton Ohios have 155 sailors on board a sub that is 170 meters long and 13 meters wide. It is crowded on the “boomers” (or “bombers” in the Royal Navy) since each of the fourteen Ohios now in service also have 24 ballistic missiles (each in a silo) and a dozen torpedoes (that use four torpedo tubes) on board plus a nuclear reactor and supplies for at least 77 days.