US nuclear-powered submarine hit uncharted underwater mountain, investigation finds

A US nuclear-powered submarine that struck an underwater object in early October had hit an uncharted underwater mountain, an investigation found, forcing it to head from the South China Sea to Guam for repairs.A US nuclear-powered submarine that struck an underwater object in early October had hit an uncharted underwater mountain, an investigation found, forcing it to head from the South China Sea to Guam for repairs.