Boeing boss Dave Calhoun will leave at the end of this year amid a deepening crisis over the firm"s safety record. Boeing also said that the head of its commercial airlines division will retire immediately while its chairman will not stand for re-election. The firm is under pressure after an unused door blew out of a Boeing 737 Max in January shortly after take-off. No-one was injured but the firm"s safety and quality control standards came under renewed scrutiny. Calhoun took on the chief executive role in early 2020 after the previous boss, Dennis Muilenburg, was ousted in the aftermath of one of the biggest scandals in its history. Within the space of five months, two brand new 737 Max planes had been lost in almost identical accidents that claimed the lives of 346 passengers and crew. When Calhoun took over, he promised to strengthen Boeing"s "safety culture" and "rebuild trust". However, in January this year a disused emergency exit door blew off a new Alaska Airlines Boeing 737 Max shortly after take-off from Portland International Airport. An initial report from the US National Transportation Safety Board concluded that four bolts meant to attach the door securely to the aircraft had not been fitted. Boeing is reportedly facing a criminal investigation into the incident itself, as well as legal action from passengers aboard the plane. Calhoun said on Monday: "The eyes of the world are on us, and I know that we will come through this moment a better company." In a letter to staff, he described the Alaska Airlines incident as a "watershed moment" for Boeing and it had to respond with "humility and complete transparency". He said he had originally agreed to become chief executive "because of the unprecedented circumstances the company was facing at the time". The Federal Aviation Administration, the US regulator, said earlier this month that a six-week audit of the 737 Max production process at Boeing and its supplier Spirit Aerosystems had found "multiple instances where the companies failed to comply with manufacturing quality control requirements". The findings came shortly after another report into Boeing"s safety culture by an expert panel found a "disconnect" between senior management and regular staff, as well as signs that staff were hesitant about reporting problems for fear of retaliation. After the two plane crashes in October 2018 and 2019, it was found that flawed flight control software caused the incidents — details of which Boeing was accused of deliberately concealing from regulators. The company agreed to pay $2.5bn (£1.8bn) to settle fraud charges and admitted deception, though in later court hearings it formally pleaded not guilty. It subsequently faced widespread accusations that it had put profits ahead of passengers" lives. As well as Calhoun, Stan Deal will leave his role as head of Boeing"s commercial airlines division immediately. He will be replaced by Stephanie Pope who has spent the past three months working as the Boeing"s chief operating officer. Larry Kellner, the firm"s chair will also leave and be replaced by Steve Mollenkopf, the former boss of Qualcomm who has been a board member at Boeing since 2020. He will lead the search for a new chief executive. — BBC