FILE PHOTO: David Calhoun is congratulated after his company's IPO opened on the floor of the New York Stock Exchange

Nielsen CEO David Calhoun is congratulated after his company's IPO opened, on the floor of the New York Stock Exchange in 2011. Calhoun took over as Boeing's chief executive Monday.

WASHINGTON, D.C. — Boeing’s new chief executive, David Calhoun, assumed the job on Monday as the U.S. planemaker battles to recover from two fatal crashes of 737 MAX planes that killed 346 people in five months and led to the model’s worldwide grounding in March.

Calhoun, 62, a longtime Boeing director named chairman in October after the board stripped Dennis Muilenburg of the title, was named chief executive on Dec. 23 following the board’s firing of Muilenburg amid growing concerns about the company’s relationship with regulators and its handling of the MAX.

Boeing has estimated costs of the MAX grounding at more than $9 billion to date and is expected to disclose significant additional costs during its fourth-quarter earnings release on Jan. 29. Boeing faces rising costs from halting production of the MAX this month, compensating airlines for lost flights and assisting its supply chain. It is also considering raising more debt.

Calhoun, a former executive at Blackstone private equity group and experienced corporate crisis manager, is already working to repair the company’s relationships with regulators, airlines and lawmakers. He previously headed a General Electric division that included airplane engines.

Calhoun told employees in an email on Monday he sees “opportunities to be better. Much better. That includes engaging one another and our stakeholders with greater transparency, holding ourselves accountable to the highest standards of safety and quality, and incorporating outside-in perspective on what we do and how we do it.”

Last week, the board and its interim CEO reversed course and recommended regulators require simulator training for pilots before they resume flying the MAX. Directors also authorized the release of more than 100 pages of damaging internal messages that disclosed company efforts to avoid costly simulator training for the MAX amid troubling questions about its culture.

In one email, an employee said the 737 MAX was “designed by clowns who in turn are supervised by monkeys.”

A source close to Calhoun said on Sunday it was important employees saw the emails, which Boeing last week described as “completely unacceptable.”

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