US aircraft maker Boeing says the company needs to acknowledge its "mistake" following an incident in which a cabin panel blew off an Alaska Airlines jet in mid-air.

The accident occurred soon after the Boeing 737 Max 9 took off from Portland, Oregon, on Friday last week. The plane managed to make an emergency landing, and no one was seriously injured.

Boeing CEO David Calhoun said in an address to employees on Tuesday, "We're going to approach this, number one, acknowledging our mistake."

The US Federal Aviation Administration has ordered 171 Boeing 737 Max 9 planes to be grounded.

Britain's Economist magazine quoted an analyst's estimate that Boeing would have to compensate Alaska Airlines 2.3 million dollars per day.

Officials at the National Transportation Safety Board are investigating the cause of the incident.

Quoting the crew's account, NTSB Chair Jennifer Homendy said in a briefing on Monday that the cockpit door flew open after the cabin panel blew off. She said Boeing had designed the cockpit door to open during a rapid decompression incident.

But Homendy said it was very loud and windy. She said that the crew "had trouble hearing each other, they had trouble hearing air-traffic control and they had trouble communicating during the event."

She said, "This was a really significant event with zero information at the time."