sentences:  The program was also plagued by structural issues; the Coast Guard historically uses its cutters extensively, typically 180 days at sea a year, furthering the problem this will often be in North Pacific and North Atlantic waters that are some of the roughest seas in the Northern Hemisphere.As such, the stresses on the Cutters are expected to be very severe.Structural Analysis showed that some parts of the cutter could be expected to survive only 3 years.