The Navy revealed last week the Columbia-class ballistic submarine test program is delayed because of a manufacturing defect. Adm. James Caldwell, naval nuclear propulsion program director, said some of the components for the preproduction motor were not properly insulated. "What we discovered was the sub-tier vendor did not properly flow down requirements to the manufacturer," he said during a March 14 Senate Armed Services strategic forces subcommittee hearing. The service will conduct full integration testing at a facility in Philadelphia,...