18 April 2019

About those airplane crashes



Some cogent discussion at Reddit.

4 comments:

  1. As a Seattle local, near the heart of Boeing manufacturing, I've found that a critical part of this story that hasn't necessarily reached national or international attention is the corporate politics of Boeing.
    Some years ago - around 2009 I believe? - Boeing went through a merger with another corporation. The Boeing name was kept, being widely known, but the management positions went almost entirely to the new company.
    Boeing engineers and machinists had historically been an incredibly strong union, as the managers of the company knew that these were the people who actually made the company function. While of course there are written plans for all the planes, the technical knowledge of how to build them correctly was passed down directly from old employees to new ones,somewhat like a traditional mentorship.
    Now, when the new management came in, there was already tension between the management and the union, since the union had been on strike at the start of the 2008 recession, which had caused a significant blow to company profits. Of course, there's no way the union could have known this, and sometimes that's how strikes go - but rather than understanding that they needed to bargain with the union, the new management decided to destroy it. They fired the vast majority of their senior engineers - I learned all this from a bus driver, who'd been fired just years out from retirement, after working as a boeing engineer for his entire career. They tried outsourcing production of individual parts to China and merely assembling the parts at the Washington plants, but that was a disaster - parts came back in all kinds of wrong sizes and with significant quality issues. So they realized it was critical to make everything in the same plant - and decided to build a new plant in North Carolina, a "right to work" (anti-union) state. This was also a disaster - the engineers they hired there were trying to figure out airplane manufacturing basically from scratch. Again, massive quality issues ensued. Eventually the corporate management realized just how important the mentoring of experienced engineers had been to their production, and sent the handful of engineers they hadn't fired yet to NC to train the scabs. Things stabilized after that, but they'd still lost a massive amount of knowledge and skill with all the people they'd fired. The Washington plants continued operation, at a significantly reduced volume, but the union was massively weakened.

    The bigger picture here is that Boeing has built its entire reputation on reliability, quality, and expert engineering. The old management squabbled with the union, but they knew that, and they respected it. They understood that a passenger airplane is a piece of infrastructure, something which must be absolutely reliable, easy to repair and maintain, long-lasting, and replaced with new purchases only as needed.
    The new management, despite a series of expensive manufacturing disasters which perfectly illustrated the importance of consistency, reliability, and expertise, entirely failed to learn their lesson. They view airplanes as a commodity to be marketed. They are willing to cut corners, push deadlines, mislead with marketing, and treat core safety features as "bonus upgrades" with an extra cost. Everything that has gone wrong with the 737 max can be explained by this corporate mindset.

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  2. (Part 2)
    As the video explains, the 737 max was a hastily-designed attempt to put an entirely new engine on the fuselage of the 737 line, which significantly changed the balance of the plane, and caused it to tip up into an angle which could cause stall conditions. From an engineering perspective, this should be an absolute dealbreaker. You don't launch a plane that's going to send itself into stall conditions during normal flight manouvers. That's absurd. The only sensible thing to do would be to redesign to fuselage to balance properly with the new engine. And that's absolutely normal in the world of airplane engineering. It might take a few more years, but the service life of an airplane is a good three decades, so it really shouldn't matter that much whether you're making that profit right now or a few years later.
    Only from the perspective of a company trying to make as much money as possible as quickly as possible, veiwing market competition as a game to be won in the month-to-month comparison of profits, could the decision to rush the plane to production with such a fatal design flaw possibly occur.
    And the way they chose to "fix" this problem by hiding it takes this profit-driven mindset to even more bizzare levels.
    A plane which had such severe balance issues would not have passed regulations - so they hid it with a software system.
    A plane which relied on an autonomous software system to prevent total failure would not have passed safety regulations - so they pretended it was a minor stabilization system, not a critical safety system.
    If the actual function of the tilt control system was known to pilots, it would have been obvious that the plane was a safety disaster which should never have been cleared to fly - so the pilots manual didn't mention that the system even existed.
    If pilots had known what the system was, how to tell if it wasn't working correctly, and how to manually override it, the crashes may have been averted (though the Ethopia flight data shows the pilots did regain manual control, it was too late - but they may have had to waste precious time figuring out what was going wrong.) But that information was intentionally hiden from them, entirely for the purpose of making the plane "marketable."

    Worse still is the marketing of the sensor upgrade. The automatic tilt control system relied on measurements from a sensor on the tail of the plane. Every plane had two sensors built in, but by default, only one was activated and connected to the tilt control system. If customers paid extra, they could recieve an upgrade in which both sensors were activated, compared data to eaxh other, and set off an alert to the pilot if the two sensors were reporting different readings. Such a system would have, presumably, detected the sensor reading errors responsible for causing both of the crashes. Of course, to act on this information, the pilots would still have had to know what the tilt control system was and how to manually override it.

    Boeing chose to market the plane as being functionally the same as the previous 737 designs, specifically so it would be given less thorough safety anaylsis and require less pilot training, and be on the market faster.
    Boeing specifically requested, and recieved, special treatment from the FAA - a faster and less thorough review process.
    After the second crash, Boeing lobbied the federal government not to ground the fleet, without any respect for the obvious safety concerns or the tradgedy of massive loss of life.
    Now, with the fleet grounded, Boeing is trying to claim that they can fix the planes with a software upgrade and more pilot training - even though the problem remains that the plane will tip itself into stall conditions without active intervention, and even with both pilot knowledge and a non-malfunctioning software system, that's an incredibly dangerous design flaw.

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  3. (Part 3)

    At every stage, Boeing has put their corporate interests and profit above human life and safety, with disastrous consequences. Maybe that's just what we expect from a corporation in the modern day. While the vox video gives a good explanation of how the technical issues causing the failure were rooted in greedy business descisions, it seems to take somewhat for granted that corporations will behave this way.
    But it came as a surprise to many, coming from Boeing, with its long history of engineering quality and reliability. In particular, the special treatment Boeing recieved from the FAA that allowed this mess of an airplane to pasd regulations, almost certainly wouldn't have been granted without that reputation.
    I think Boeing's new management has finally burnt through all the currency of reputation the old union built. But I think it's an important cautionary tale, in this increasing unregulated mega-corporate capitalist world - a company which destroys its unions in the name of its profit margins can't be trusted to put any other human values above the relentless pursuit of profit, either.

    I wrote all this put from memory,so pardon any innacuracies. Technical information is mostly from the Seattle Times coverage of situation, which has been very thorough. Information on the management and their union-busting shenanigans is from the various ex-Boeing engineers I've talked to over the years.

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    Replies
    1. An awesome set of comments. Thank you, Terbium.

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