Boeing provided a fresh batch of incriminating documents on the 737 MAX to regulators and congressional investigators, only hours after announcing a leadership shakeup, officials confirmed Tuesday.

The document dump came just before Christmas, when many officials already are on holiday, and "appear to point to a very disturbing picture" about Boeing's response to safety issues regarding the 737 MAX, a congressional aide told AFP in an email Tuesday.

The aide said Boeing sent the documents "late in the evening" Monday to congressional staff investigating the issues with the aircraft, which has been grounded since March following two crashes that killed 346 people.

The aerospace giant has faced scrutiny over its decision to keep flying the plane after the first crash and to brush off safety concerns of some employees, and over whether it sacrificed safety in the race to develop a plane to compete with an Airbus jet.

US regulators also have been criticised for a too-cozy relationship with the company it is charged with overseeing.

The Federal Aviation Administration confirmed it received what appear to be the same documents Monday afternoon, a few hours after Boeing ousted Dennis Muilenburg as chief executive amid his much-criticised handling of MAX crisis.

Boeing said it "proactively" contacted the FAA and Congress "as part of our commitment to transparency," a company spokesman said in email.

"As with prior documents referenced by the committee, the tone and content of some of these communications does not reflect the company we are and need to be."

The spokesman also highlighted changes Boeing has made "in the past nine months to enhance our safety processes, organisation and culture."

That references the period after the Ethiopian Airlines crash in March. The first 737 MAX crash of a Lion Air flight in Indonesia happened five months earlier.

The latest revelations make it clear that despite shaking up its leadership, Boeing will continue to face questions well into 2020 over the actions that led to the crashes as it tries to win approval to return the MAX to service and to restore its damaged reputation.

The document dump -- which surfaced on a normally tranquil Christmas Eve -- came hours after Boeing announced it was replacing Muilenburg with Chairman David Calhoun, saying the company needed to "restore confidence" and "repair relationships with regulators, customers and all other stakeholders."

FAA Chief Steve Dickson ripped Boeing in October after the company only provided the agency with revealing documents months after unearthing the records.

More trouble for Boeing
The global fleet of Boeing 737 MAX planes have been grounded since March following two deadly crashes. Photo: GETTY IMAGES NORTH AMERICA / David Ryder

In one text message exchange that surfaced in those documents, a Boeing pilot described a problem on a simulator with a flight handling system that has been implicated in both crashes.

The aide with the House Transportation Committee declined to release the latest papers on Tuesday and said committee staff were still reviewing the documents.

"The records appear to point to a very disturbing picture of both concerns expressed by Boeing employees about the company's commitment to safety and efforts by some employees to ensure Boeing's production plans were not diverted by regulators or others," the aide said in an email.

The panel is led by Democratic Representative Peter DeFazio, who grilled Boeing executives at an October hearing at which some lawmakers called for Muilenburg to resign.

DeFazio on Monday called Muilenburg's ouster "long overdue," and said the company "made a number of devastating decisions that suggest profit took priority over safety."

The CEO shakeup at the company drew muted response Tuesday from Wall Street analysts, a bombshell that came only days after the company took the monumental step of halting production on the 737 MAX and a day after it suffered a setback on a high-profile NASA mission.

Bank of America Merrill Lynch said it had "mixed feelings" in light of Calhoun's lengthy tenure on the Boeing board.

"We wonder if appointing from within, especially an insider that has been with the company for 10 years, signals more of the same from Boeing vs an outside appointee who may have offered more of a change of pace and culture," the bank said in a commentary.

JPMorgan Chase said Muilenburg had struggled as a public voice for Boeing in response to the tragedies and in communication with regulators and customers.

"We expect David Calhoun to do better on both scores. This is something," JPMorgan said in an analysis.

"But Boeing's failures on the MAX are more than poor communication so it will be important for Mr. Calhoun to show early how he intends to act differently.

"This is particularly important since he has been a director since 2009 and therefore part of this situation from the start, even if in an oversight role."

Copyright AFP. All rights reserved.

More trouble for Boeing
More trouble for aerospace giant Boeing over its handling of the 737 MAX crisis. Photo: AFP / Jason Redmond