FAA Discovers Flaw in How Boeing 737 MAX Pilots are Supposed to Respond to MCAS Problems

The FAA has been trying to get other countries on board with re-certifying the Boeing 737 MAX. Some industry leaders, such as American Airlines CEO Doug Parker, are so confident and ready to see the plane back in the skies that they attribute delay to political gamesmanship.

However one new wrinkle has been uncovered in Boeing’s quest to have the aircraft re-certified.

Reportedly “[d]uring simulator testing last week at Boeing, FAA test pilots discovered an issue that affected their ability to quickly and easily follow the required recovery procedures for runaway stabiliser trim.” A microprocessor failure has been discovered to be able to trigger the MCAS system and in tests pilots haven’t been able to quickly recover from such a failure.

The FAA confirms identifying “a potential risk that Boeing must mitigate” apparently related to how the flight computer processes data and creates problems when pilots following the recommended runaway stabilizer procedure in response to mistaken activation of the MCAS (manoeuvring characteristics augmentation system), the software which has been implicated in the Ethiopian and Lion Air MAX crashes.

It remains to be seen whether a software fix can address the microprocessor problem or whether the processors themselves will need to be replaced.

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community InsideFlyer.com, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. Unbridled greed coincided with uncharacteristic incompetence, now overlaid with indecent haste to get the thing flying again, trampling over the graves of the victims.
    The MAX won’t fly this year, if ever. How the CEO keeps his job beggars belief.

  2. @Paolo: You’re right, how arrogant and slicky snake CEO Mullenberg keeps his 25 million dollar job shows just how thoroughly unaccountable corporate kingpins are. Not one single Boeing person will be prosecuted for a monumental and IMHO conscience decision to allow the flaw in the MAX aerodynamics to go ahead for certification. The FAA too is corrupt to the core. Profits over people. Period. Even if 346,000 passengers died the same play out we are seeing would take place. Money is for spending. People are expendable. Remember the financial crisis? Not one single banker, worker, CEO, none were held to account. Instead the Feds rewarded them. And the country accepts the total corruption as normal. Welcome to the third world.

  3. Who made the microprocessors? I wonder. Why isn’t the computing fault tolerant? Anyone can make one or two mistakes. To Err is Human. However, the multiple problems with this plane (software, sensor, training, completing testing with computer simulations rather than actually flying, blaming pilot error for the problems with the plane……) shows that Boeing has become sloppy in its designing and manufacturing. Managements single minded focus of getting the plane to fly again rather and making excuses is pathetic. Wouldn’t touch Boeing stock with a 90 foot pole (used to be a 20 foot pole).

  4. The Flight Global article (6/26/19) article that Gary cited above stated: “During simulator testing last week at Boeing, FAA test pilots discovered an issue that affected their ability to quickly and easily follow the required recovery procedures for runaway stabiliser trim”. It sounds like Boeing is throwing fixes against the FAA wall, to see what sticks. Boeing should not be pushing out fixes unless they are positive they work. Pathetic.

    The CNN article (6/26/19) that Gary cited above stated: “Boeing has proposed computer-based training which could be completed quickly and on an iPad.” Seriously, maybe I will be qualified to fly a jet based on flying pilot programs on my home computer. NOT. Does Boeing’s management even contemplate how serious this issue is. Again Pathetic.

    Everyone, read the cited articles above, you will not be happy. Boeing’s management has to go.

  5. I keep on saying the same thing again and again: the 737 Max is an old outdated design that Boeing is trying to keep flying with software.

    Good that you keep on highlighting this. It is disappointing that Ben and Matthew have been very silent on the 737 (and 787) issues. Maybe because they are US bloggers? I see this topic much better covered on international blogs. And yours.

  6. It seems that Boeing needs a change of senior leadership.
    How is the flying public supposed to trust these people. Buybacks and junkyard next?

  7. Other Just Saying – pilot training on an iPad is basically one step down from “simulator training required”. Of course it sounds silly because you play Candy Crush on your iPad, but pilots routinely submit flight plans, complete training, and other tasks on iPads so it’s not a sign that’s it’s being taken lightly.

  8. @Steve S. If the situation was normal, I would agree with you. But it is not. 346 died in two crashes because the pilots were unable react properly to the 737 Max software. Therefore, this should not be a standard roll-out of a software update on an Ipad. Boeing should want to make sure that every pilot flying the plane is absolutely trained on how to fly the plane. I mean, quadruple sure. Aside from the lives potentially lost, another 787 Max going down, because a pilot was not properly trained, would be a catastrophe for Boeing.

  9. @Steven O – You may be right on Boeing, but your comment ” Remember the financial crisis? Not one single banker, worker, CEO, none were held to account. Instead the Feds rewarded them.” is just horrendously incorrect and fake news. Nobody was held accountable? Thousands of employees of Lehman Brothers and Bear Stearns (8,000 in fact) paid the price. There were waves of layoffs at just about every investment bank globally leading to hundreds of thousands of layoffs, impacting regular working people from back office to the front office. Life savings of bankers and their families were wiped out when some of these companies failed. You’re just plain wrong and out of touch with reality. For those of us that watched our friends wake up one morning to find out their employer no longer existed, it’s just a step too far. Have some respect.

  10. I hope Alaska will continue to hold on to the Airbus aircraft they got. This is worse than the DC-10. To me, there is even echoes of Challenger. How senior management is still in charge is mindboggling. BTW-Dominic Gates of the Seattle Times has written extensively on the MAX.

  11. Boeing used to be a leader in aviation no longer is that true. Senior management should be held accountable at the very least. Then the President of the Commercial Airplanes and VP of Quality
    should be fired due to incompetence. The list could go on but Boeing is to politically connected to have anything happen, Boeings downfall started with the acquisition merger with McDonnell Douglas and has been a downhill slide ever since.
    All the comments mentioned are spot on unfortunate they never nit mainstream Media.

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