USA TODAY International Edition
Boeing shares flight-control fixes on Max 8
Boeing proposed software changes to its embattled 737 Max aircraft Wednesday and mandated more pilot training, moves it hopes will allay concerns about the jetliner’s safety and get it back in the air.
The changes – previewed at the company’s facilities in Renton, Washington – focus on a flight-control system designed to keep the plane’s nose from pitching up, which figured in one crash and is suspected of playing a role in a second. Boeing is under pressure as flight cancellations mount because of grounded jets, and it faces scrutiny from Congress.
FAA Administrator Daniel Elwell testified before a Senate panel Wednesday on the agency’s decision to keep Max 8s in the air as other countries grounded them after an Ethiopian Airlines crash of a Boeing 737 Max 8 jet this month in which 157 people died.
Indonesia’s Garuda Airlines canceled its order because of loss of confidence in the 737 Max.
“We’re working with customers and regulators around the world to restore faith in our industry and also to reaffirm our commitment to safety and to earning the trust of the flying public,” said Mike Sinnett, Boeing vice president for product strategy and development.
The changes will be made to the Maneuvering Characteristics Augmentation System, or MCAS, which was meant to automatically take over if a plane’s nose suddenly rose in a way that could lead to stalling.
A possible flaw in the system was blamed in the Lion Air crash of a 737 Max 8 over the Java Sea late last year that killed 189, and it’s being investigated in the Ethiopian Airlines crash involving the same model of jet.
Now, the MCAS will compare readings from two sensors that monitor for the plane’s forward angle. If the sensors disagree by 5.5 degrees, the MCAS won’t activate. A warning light, previously an option, will alert pilots, Boeing said.
The changes will make it easier for pilots to override the system and fly the plane themselves. If they pull back on the wheel, the system won’t counteract them. Before the Lion Air crash, pilots tried multiple times to use the controls to push the plane’s nose down or disable the system, but the system kept initiating again.
The MCAS will no longer keep turning itself on. It will turn on only once if the sensors find the plane’s angle of attack is too extreme.
Boeing plans to mandate more training in the difference between the Max and other versions of the 737, including understanding of the MCAS. It would be in addition to the 21 days of training required to fly 737s.
The changes to training have been “provisionally approved” by the Federal Aviation Administration, and the software improvements need to be reviewed, Boeing said. It is yet to be seen whether they are significant enough to get the plane flying again.