In major shakeup of Boeing’s leadership, CEO Dave Calhoun said Monday he intends to leave the beleaguered company by the end of the year. The company’s chairman and head of the commercial airplane unit are also leaving.

Boeing’s chairman, Larry Kellner, will not stand for re-election as a board director. The board has elected former Qualcomm CEO Steve Mollenkopf to succeed him.

The company also announced that Stan Deal, CEO of Boeing Commercial Airplanes, is retiring. Stephanie Pope, Boeing’s chief operating officer since January, is taking his place effective immediately.

Boeing has been buffeted by more than five years of problems with its airplanes, including two fatal crashes of the 737 Max in 2018 and 2019 that killed 346 people, and most recently a door plug that blew out of the side of an Alaska Airlines 737 Max in January, leaving a gaping hole in the side of the plane. The problems have led to multiple groundings for safety issues and more than $31 billion in cumulative losses.