The head of the Federal Aviation Administration told a U.S. House subcommittee on Tuesday that safety culture improvements at Boeing may take three to five years to complete. "It is not a six-month program - it is a three-year to five-year program,

Boeing must do more to improve the aircraft safety following a door plug blowout in January and other mishaps, Federal Aviation Administration Administrator Mike Whitaker told a House committee Tuesday.

The head of the Federal Aviation Administration will tell Congress on Tuesday the agency will hold Boeing accountable to ensure the planemaker is building safe airplanes and will revamp its own safety management program.