Boeing

Boeing’s Proposed Solution to Max 8’s MCAS System

The Wired reporting:

The solution, then, is twofold: Boeing started by warning airlines that the MAX’s angle of attack sensors had malfunctioned before, that such a failure could lead the MCAS (Maneuvering Characteristics Augmentation System) to push the plane’s nose down, and that pilots could safely defuse the problem by cutting off the trim system and working the plane manually.

After making sure pilots knew about the problem and how to resolve it, Boeing would work on a longterm solution. Essentially, it would rejigger the software governing MCAS so that it wouldn’t be as prone to jumping into action based on one scary sensor reading, instead considering more data. And it would limit how many times it can engage.

Boeing said it would have it done within a few months. Then the Ethiopian Airlines jet crashed. We don’t yet know if the jet’s MCAS system is what brought the plane down, or what other factors may have been at work. We do know that what seemed a straightforward fix to an unforeseen problem is now muddied—and that the 737 MAX won’t take off again until it’s been cleared up.

Maneuvering Characteristics Augmentation System sounds like a software hack…

Boeing 737 Max 8 Design Issues

The Air Current:

Every airplane development is a series of compromises, but to deliver the 737 Max with its promised fuel efficiency, Boeing had to fit 12 gallons into a 10 gallon jug. Its bigger engines made for creative solutions as it found a way to mount the larger CFM International turbines under the notoriously low-slung jetliner. It lengthened the nose landing gear by eight inches, cleaned up the aerodynamics of the tail cone, added new winglets, fly-by-wire spoilers and big displays for the next generation of pilots.

It pushed technology, as it had done time and time again with ever-increasing costs, to deliver a product that made its jets more-efficient and less-costly to fly.

In the case of the 737 Max, with its nose pointed high in the air, the larger engines – generating their own lift – nudged it even higher. The risk Boeing found through analysis and later flight testing was that under certain high-speed conditions both in wind-up turns and wings-level flight, that upward nudge created a greater risk of stalling. Its solution was MCAS, the Maneuvering Characteristics Augmentation System control law that would allow for both generations of 737 to behave the same way.

MCAS would automatically trim the horizontal stabilizer to bring the nose down, activated with Angle of Attack data. It’s now at the center of the Lion Air investigation and stalking the periphery of the Ethiopian crash.

Pilots Complained About Boeing 737 Max 8 Before Accidents

Dallas News reporting:

Pilots repeatedly voiced safety concerns about the Boeing 737 Max 8 to federal authorities, with one captain calling the flight manual “inadequate and almost criminally insufficient” several months before Sunday’s Ethiopian Air crash that killed 157 people, an investigation by The Dallas Morning News found.

The News found at least five complaints about the Boeing model in a federal database where pilots can voluntarily report about aviation incidents without fear of repercussions.

The disclosures found by The News reference problems during Boeing 737 Max 8 flights with an autopilot system, and they all occurred while trying to gain altitude during takeoff — many mentioned the plane turning nose down suddenly. While records show these flights occurred during October and November, the information about which airlines the pilots were flying for is redacted from the database.

Records show a captain who flies the Max 8 complained in November that it was “unconscionable” that the company and federal authorities allowed pilots to fly the planes without adequate training or fully disclosing information about how its systems were different from other planes.

Which Airlines Have Boeing 737 Max 8

New York Times:

Which Airlines Have Boeing 737 Max 8? At least 20 airlines around the world have grounded their 737 Max 8 planes.

Source.

For an up to date list visit the official airline webpages.

Fox News:

Two top Democratic U.S. senators called on Boeing to ground all 737 Max 8 planes operating in the United States while the deadly weekend crash of an Ethiopian Airlines jet is investigated, while the head of the House Transportation Committee said Monday that he would “think twice” about boarding the aircraft in the future.