Boeing faces 'long road' on safety issues, US FAA says

U.S. planemaker Boeing faces a "long road" to address safety issues, the head of the Federal Aviation Administration said on Thursday as it prepares to receive the company's plan to address concerns.

In late February, FAA Administrator Mike Whitaker gave Boeing 90 days to develop a comprehensive plan to address "systemic quality-control issues" and barred it from expanding 737 MAX production.

Boeing has faced mounting questions after a door panel detached during a Jan. 5 flight on a new Alaska Airlines (ALK.N)

, opens new tab 737 MAX 9, forcing pilots to make an emergency landing while passengers were exposed to a gaping hole 16,000 feet above the ground. An FAA audit also found serious issues.

Whitaker told ABC News the 90-day plan, due next week, "is not the end of the process. It's the beginning and it's going to be a long road to get Boeing back to where they need to be making safe airplanes."

He said the FAA has been working closely with Boeing over the last 90 days on "what that