The Navy needs to revise cost estimates for its Columbia-class submarine construction and develop a consistent method of identifying whether supplier development funding (SDF) is helping the program correct its schedule, the Government Accountability Office reported Monday . The Navy concurred with five GAO recommendations on the nearly $130 billion program, which is currently expected to deliver its lead submarine 12 to 16 months after the originally planned date , according to the Navy’s most recent shipbuilding review. The program...