WASHINGTON (AFP)

The US Federal Aviation Administration (FAA) said that all 737 MAX 9 planes would remain grounded until Boeing provides further data following a near-catastrophic incident on an Alaska Airlines-operated aircraft.

"For the safety of American travelers the FAA will keep the Boeing 737-9 MAX grounded until extensive inspection and maintenance is conducted and data from inspections is reviewed," the FAA said in a statement.

In the dramatic January 5 incident, Alaska Airlines Flight 1282 from Portland executed an emergency landing after a panel known as a "door plug" blew out mid-flight. There were no fatalities or serious injuries.

The FAA has launched a safety probe into the incident, the first major in-flight safety issue on a Boeing plane since fatal 2018 and 2019 737 MAX crashes that led to a lengthy grounding of the aircraft.

"We are working to make sure nothing like this happens again," FAA administrator Mike Whitaker said.

"Our only concern is the safety of American travelers and the Boeing 737-9 MAX will not return to the skies until we are entirely satisfied it is safe."

The FAA said it needed additional information from Boeing before approving the manufacturer's proposed inspection and maintenance instructions.

The regulator said it "will not approve the inspection and maintenance process until it reviews data from the initial round of 40 inspections," but added that it was "encouraged by the exhaustive nature of Boeing's instructions for inspections and maintenance."

Earlier on Friday the FAA said it was planning to increase its oversight of Boeing production and manufacturing, including auditing its 737 MAX production line and suppliers.

The regulator said it was also exploring the use of an independent third party to oversee Boeing's inspections.

"It is time to re-examine the delegation of authority and assess any associated safety risks," Whitaker said.

"The grounding of the 737-9 and the multiple production-related issues identified in recent years require us to look at every option to reduce risk."

The FAA action has affected hundreds of flights.

Alaska Airlines, which operates 65 737-9 MAX planes, said it was cancelling around 110-150 flights a day through Tuesday due to the grounding.