Dennis Muilenburg is out as CEO at Boeing as the company has ceased production of its troubled 737 MAX almost a year after the first of two fatal crashes that grounded the global fleet of aircraft.
Muilenburg stepped down on December 23 and will be replaced by Boeing Chairman David Calhoun on January 13. Analysts see this as a move to shore up confidence in the company and its aircraft—though that confidence is in short supply.
It’s likely that Muilenburg’s claims that regulators would allow the plane to return to service in late 2019—and the grilling he received from Congress—triggered his removal.
In December the FAA admonished Boeing for pushing the regulator to recertify the MAX unrealistically soon—reflecting a cozy relationship between the FAA and Boeing that has come under scrutiny. The FAA discovered after the first crash that the plane had design flaws that could have resulted in a crash every two or three years if the flight control software wasn’t improved—but the regulator allowed the MAX to continue flying anyway on the assumption that Boeing would fix the software. The company didn’t end up doing so until after the second crash drove global regulators to ground the fleet.
“The Board determined that a change in leadership was necessary to restore confidence in the company moving forward and that we will proceed with a renewed commitment to full transparency, including effective and proactive communications with the FAA, other global regulators and our customers,” said CFO Greg Smith, who became interim CEO.
Boeing has been working on a fix for the problematic Maneuvering Characteristics Augmentation System (MCAS) software that caused two crashes by repeatedly pushing the MAX's nose down despite crew attempts to keep the plane level.
In spring 2019 the company claimed it was finalizing the fix. The upgraded MCAS will now use information from two angle of attack sensors on the plane—previously it relied on only one sensor—and will only activate if data from both sensors agree. Also, MCAS will only activate a single time and it will no longer provide more input than the pilot can handle using the control column alone—meaning the software will no longer be able to overpower the pilot.
As of mid-December Boeing has conducted over 1,012 test and production flights with the updated MCAS software, totaling more than 1,864 hours. The planemaker is also making a second software update that provides additional flight control computer redundancy.
The MAX remains grounded months after Boeing made those changes—indicating that the MCAS may be only part of a bigger problem. In addition, crash investigations are still ongoing, which may be influencing the regulator’s reluctance to allow the planes to fly again.
“I have been curious how it could be the case that in April, Boeing announced in just a few weeks we have the fix it’ll be delivered to the FAA in a few weeks,” said Stan Sorscher, a former Boeing engineer and official at SPEEA, the aerospace engineers' union. “That assurance is repeated and repeated and repeated and we never quite find out what is holding up the certification.”
The software relied on data from angle-of-attack sensors that measure the angle of attack at which the wings meet the direction of the air flowing over the wings. If this angle is too steep the air flowing over the wings is disrupted, causing the wings to lose their lift and potentially cause the plane to stall. In both crashes the sensors triggered the stall warning even though they weren’t anywhere close to stalling.
The sensors themselves consist of small vanes on the outer skin of the plane’s nose—vanes that could easily be damaged from bird strikes, mishandling on the ground and being bumped by a boarding gate. Regulators may call on the planemaker to strengthen those sensors in addition to modifying the MCAS to rely on more than just one.
Staff at Transport Canada, the Canadian aircraft regulator, have suggested removing the MCAS entirely. Transport Canada and the FAA both stated that the suggestion is part of working-level discussions between regulators and have not committed to that course of action.
With recertification still months away, Boeing is taking the unprecedented step of halting production of the 737 MAX—setting off ripple effects in a global supply chain of suppliers in the United States and around the world that have been feeding components into Boeing’s plane factories. It is also estimated to cut the U.S. GDP growth rate by half a percent in the first quarter of 2020—an indication of just how significant this crisis has become.
Before the crashes, Boeing was making 52 of the popular planes a month. After the grounding it slowed production to 40 a month—but has been running out of places to store the aircraft.
Airlines are already feeling considerable financial pressure, repeatedly pushing back their own schedules for returning their MAX planes to service well into 2020 at mounting costs.
The grounding of the 737 MAX has been the biggest aerospace story of the year for 2019—indeed, one of the biggest stories of the year. And it looks to continue dominating both headlines and the economy in 2020 as regulators and Boeing continue to work to get the best-selling plane back in the air.
Read more about the 737 MAX at 737 MAX Senate Hearings Expose Deep Flaws at Boeing.