Boeing CEO Dave Calhoun announced on Monday that he will step down by the end of this year as part of a broader plan to restructure his leadership following a dramatic series of incidents involving the company’s planes, Reuters reported.

The plane maker also announced that Stan Diehl, president and chief executive officer of Boeing Commercial Airplanes, will also step down and that Stephanie Pope, who is now Boeing’s chief operating officer, will lead the business.

Steve Mollenkopf was appointed to chair the board of directors.

Calhoun has been under pressure since the start of the year when the doors on a Boeing 737 MAX peeled off mid-flight after a panel supporting them failed, an incident still under investigation by aviation authorities. Preliminary results of the investigation indicate that 4 screws that were supposed to fasten the door were not installed.

But a series of dramatic incidents that followed increased pressure on him and led to a congressional investigation into the company in Washington.

U.S. regulators have ordered Boeing to limit production as the company struggles to address safety and quality issues.

Last week, a group of U.S. airline executives asked to meet with Boeing bosses to voice their concerns, an unusual move that analysts say shows frustration with the plane maker and Calhoun’s leadership.

But at the same time, experts note that not all incidents involving Boeing aircraft this year can be attributed to the fault of the manufacturer. For example, although the cabin door incident occurred on an Alaska Airlines flight, most of the other incidents occurred on the planes of one airline: United Airlines in the United States.

Boeing shares fell sharply on the stock market

Boeing, meanwhile, said it was in talks to buy Spirit AeroSystems, its subcontractor that installed doors on Alaska Airlines planes, to improve oversight of the quality control process.

The crisis of confidence that Boeing is currently facing comes after repeated delays in the delivery of planes frustrated customers, especially in the context of the “boom” that air travel is experiencing after the end of the COVID-19 pandemic.

Airbus, the American planemaker’s main rival, last week won contracts to supply 65 planes from two of Boeing’s key Asian customers, a deal that some saw as a new sign of concern about Calhoun’s leadership.

Boeing’s stock price has fallen sharply since the start of this year, falling from $251 at the U.S. stock market open on Jan. 2 to $188 at the close of its most recent trading session.

“They (Boeing) need more than a CEO and chairman restructuring (…) I think Dave Calhoun has been scapegoated, not necessarily by the board, but by the government,” Robert Pavlyuk, a portfolio manager, told Reuters. in investment company Dakota Wealth.

“The company will not stop its activities, the (US) government will not allow this to happen. Boeing needs the government, and the government needs Boeing,” he added.