Boeing is promising three fixes for the faulty system widely blamed for the two deadly 737 Max crashes, CBS News reported on Sunday.
The manufacturer told stakeholders in Seattle last week that it would introduce changes to the jets' Maneuvering Characteristics Augmentation System, CBS News reported, citing documents from a presentation by the company.
Investigators found that the pilots in both crashes struggled with MCAS, which was designed to automatically push the plane's nose down to stabilize it if it detects a stall.
Before a jet from Indonesia's Lion Air crashed last year, MCAS had activated at least 20 times, investigators said.
The software had relied on data from one of the plane's two "angle-of-attack" sensors, which monitored the plane's position in the sky. Both pilots tried to push back against the system by angling the plane back up dozens of times, but MCAS kept reactivating.
The two crashes killed a total of 346 people.
CBS News reported that Boeing said it had addressed these problems with updated software and would make these changes:
- MCAS will now rely on readings from two sensors as opposed to just one in the original system. The new software will activate only if both sensors agree that the plane's nose is too high. Boeing had announced this update earlier this year.
- Pilots will be able to override the system.
- When they do so, MCAS will not automatically reactivate, which the original system would do multiple times.
Boeing also told stakeholders that it had flown 1,850 hours with the software updates and spent more than 100,000 hours engineering and test-developing them, CBS News reported.
Multiple Boeing employees have spoken about internal pressures to develop planes quickly and keep manufacturing costs down.
Boeing did not immediately respond to Business Insider's request for comment on the reported changes.
The company's presentation last week was meant to reassure analysts, airlines, pilots, and flight attendants about the 737 Max, CBS News reported. Regulators around the world have grounded those jets, and pilots and flight staff members have publicly expressed fears about flying them again.
The US Federal Aviation Administration has also come under pressure for vouching for the 737 Max's safety before the two crashes. The agency now wants to dramatically change its certification process.
Internal messages exchanged by Boeing employees in 2016 and released in October also suggested they had known about the MCAS's problems but misled the FAA about its dangers.
The 737 Max is expected to return to service in March, though Boeing is trying to get it back in the air sooner.
- Read more:
- Boeing's CEO is about to face Congress in an inquiry on the 737 Max. Here's the complete history of the plane that's been grounded since 2 crashes killed 346 people 5 months apart.
- Internal Boeing survey hints at a culture of rushing through aircraft safety features in the years before 2 fatal 737 Max crashes
- The spotlight on Boeing and the FAA will only get hotter after the 737 Max crisis. Now global regulators are focusing on the plane maker's newest jet.
- Boeing's 737 Max shouldn't be allowed to fly with a controversial flight-control system, an aviation regulator reportedly said in leaked emails
