Pontifications: Remembering two other mysterious 737 accidents

By Scott Hamilton

April 8, 2019, © Leeham News: Boeing’s corporate response to the crash of Lion Air JT610 was initially to blame the pilots of the former and defend the airplanes in that accident and the Ethiopian Airlines ET302 crash.

Neither is surprising in this world of instant lawsuits.

These actions are also in Boeing’s corporate culture.

But in a major shift in corporate tone, Boeing CEO Dennis Muilenburg last Thursday issued a video in which he said Boeing “owns” the MAX accidents. This is very un-Boeing. (It will be interesting, however, to see how Boeing’s legal team responds to the lawsuits.)

I’m reminded of the last time the 737 was involved in two mysterious crashes in which Boeing blamed the pilots in one of them. The causes of the two accidents turned out to be placed squarely on the airplane, however.

United and US Air crashes

In the cases of United Airlines 737-200A Flight 585 and US Air 737-300 Flight 427, crashes three years apart in Colorado Springs and Pittsburgh, the airplanes were on approach for landing. Without warning, the aircraft made a sharp turn and dove into the ground, killing all aboard.

The investigators were stymied and Boeing blamed the US Air pilots. Two years after the US Air crash, an Eastwind Airlines 737-200A experienced a rudder hardover. The incident occurred at cruising altitude and the flight recovered.

A valve controlling the rudder proved to be the causes of the two fatal crashes and the Eastwind incident.

Book details the investigations

The Mystery of Flight 427, by Bill Adair, at the time the aerospace reporter for The St. Petersburgh (FL) Times, outlines the crashes and investigations. This excerpt describes the faulty valve.

Adair’s book details the investigations and the tests that led to the discovery there was a problem with the value and the airplane itself. It also details Boeing’s corporate stances, blaming the pilots.

So when Boeing initially blamed the pilots of Lion Air, it wasn’t a surprising corporate response. Nor, in fairness, was it especially surprising about Lion Air, which has a bad reputation for safety. The European Union even banned the airline from its skies.

Boeing’s response blaming the Lion Air pilots got all kinds of blow back. It was restrained after the Ethiopian accident, with no fingers pointed to the pilots—at least not directly.

Officials steadfastly stood behind the airplane, even as they began working on a software upgrade shortly after JT610 and right through the ET302 crash and beyond. Nothing was wrong with the design of the MCAS stall recovery system, they said. The upgrade would merely make the system more “robust.” It would make a safe airplane even safer, Boeing said. (One critic noted that a plane is either safe or it isn’t.)

Limitations on comments

Boeing is limited as to what it can say, under rules of being a party to investigations. This puts it in a difficult position to comment, though it did blame the pilots and defend the airplane. Its corporate lawyers undoubtedly are driving everything that is said. (This is often the case even outside of accidents.)

Muilenburg’s message last week hit the right tone. It’s a refreshing change in Boeing’s usual response. It’s tragic that it’s come under these circumstances.


96 Comments on “Pontifications: Remembering two other mysterious 737 accidents

  1. There are some more accidents around where the leading/or only involved US based investigators pressed for pilot error and made it stick though the other involved parties had difficulties with “taking” that assessment.
    Same old song : “pilot extended suicide” or “incompetent third worlders”.

    Maybe these too should be revisited?

  2. Good to see LNA acknowledging that both 737 MAX crashes were caused by the airplane and not the pilots.

    Unfortunately to those of us who know, the FAA and Boeing both knew is was the airplane not the pilots soon after the Lion Air crash. Yes, they issued an emergency AD but we now know the FAA and Boeing were keeping secrets because they are now having to own up to those secrets because of the Ethiopian Airline crash.

    The 737 MAX should have been grounded within a few weeks and perhaps a few days of the Lion Air crash. The Ethiopian Airline crash was avoidable.

    A long wss back for the FAA and Boeing.

    • Phillip:

      LNA has never said it was NOT the aircraft and in fact, Bjorn has been even more adamant that the pilots were faced with overload than I have been (yes they were though I felt Lion Air could have kept flaps down)

      That is totally out of place remark. LNA has always called it without a bias to Boeing.

      • Although I’m pretty new here, I agree with TransWorld on both counts. I’d never have gone from lurker to poster had I not been so appreciative of the work Bjorn, Scott and the other staff put in.

      • Short memory TransWorld.

        Read LNA’s articles in response to the Lion Air crash. Then read your comments when I told off LNA.

        My memory is that it took you several months to admit the airplane was at fault. Even now your posts still wobble.

        There are more relevations to come. I actually think the Lion Air crash was avoidable for the 737 MAX should never hsve been certified. But I without my fire.

        Have a nice day!

        • Philip: Your memory is indeed as flawed as MCAS.

          I hold pilots partially responsible, Bjron feels no. I respect his view highly.

          It did not take months, it simply took the outing of the MCAS.

          As more has come out I have gone more to Bjorns end.

          The one aspect that is in pilots arena to me is that when they put the flaps back down, it stopped. As that obliviously was in reaction to it started when the flaps went up, its a huge question mark.

          US pilots have vastly better protection. I suspect from both the previous flights and the pilots aciotn in attempting to continue the flight that pressure to make the run and dump the issue into the next crews lap is paramount.

          As information continues to come in, its clear that the authority on the stabilize was insane, adding into the disuse with Manual trim not possible (or extremely difficult) when the speed goes high.

          Ehtripoin clearly followed the recooemdn and it did not work.

          At that point its a hail mary.

          My take is flaps effeicly neuters MCAS, worht a shot. Stabs back on puts MCAS back in the loop.

          What I would have done I don’t know, I was not on the pointy end of the spear.

          I have been and did the right thing(s) but you don’t know as each one is a new chance to get it right or be a pilot of Aluminum.

          While I disagree with you assessment and review of the comments for LNA and myself, I also appreciate the moderate tone taken.

          Hopefully you have a nice and all of us have a better one than Lion 610 or Ethiopian 409.

  3. I am suspicious Boeing knows, as per the complaints from US pilots to the FAA about non-fatal incidents in the MAX, that the MCAS actuation isn’t only happening as designed, and the cut out switches/modes of flight are not functioning as it essentially has trained pilots (now.).

    I think they are working through how to reveal that, and the multiple fixes to it. It’s why they created this safety council, and have taken some ownership; the scope of the ‘software glitch’ is bigger than most have realized.


    • Or if possible not reveal it.
      I am suspicious as well, just something about the language.

  4. ‘Muilenburg’s message last week hit the right tone. It’s a refreshing change in Boeing’s usual response. It’s tragic that it’s come under these circumstances.’

    Sorry Scott I don’t agree with you. It was the absolute minimum he could have said. He also adopted interesting uses of tenses (past, present, future) to infer that they were being proactive as opposed to reactive. There was no direct admission of wrongdoing beyond the ‘own it’ and we have to remember this is the same person who mentioned ‘a safe aircraft even safer’.

    The whole statement smacked of being written by someone else, having been revised a thousand time, having been massively rehearsed and still not ringing true.

    if Muilenburg had any guts he would allow himself to be interviewed rather than hiding behind a video. As it stands he is hiding himself away and avoiding any difficult questions. The issue is do you think he has acted with integrity in his dealing about the MAX and is he sufficiently trustworthy and has the judgement to run such an important company? The answer to the first question is a definite no and the jury is out on the second one.

    • @sowerbob: I’ve no doubt the statement, if not written by lawyers, was vetted by them.

      But trust me: I’ve been following Boeing for 30 years. Muilenburg’s statement was very on-Boeing like

      • @Scott, Er, is there a typo?

        “But trust me: I’ve been following Boeing for 30 years. Muilenburg’s statement was very *un*-Boeing like”

        As you yourself have observed, the events surrounding these 737MAX tragedies have been unprecented. Having broken a few precedents already, perhaps there’s just a lot of momentum building to smash through a few more…

        Part of me (the nasty, cynical part. Sorry) wonders whether or not this apparent mea culpa is some sort of preemptive action to soften the consequences of any possible future court findings. Perhaps Boeing’s lawyers have already assessed the matter, looked at various internal documents / emails, and said “you ain’t got a snowball’s chance in hell”. PR would then move on to damage limitation.

        And as for the statement itself, that Boeing “owns” the crashes, well that’s just observing a fundamental constant truth. Whatever the cause of a crash, even deliberate actions by a pilot, there’s always merit in taking a serious look at seeing if more could have been done on the design.

        For example, after the MH370 both Boeing and Airbus could have decided to take the matter of real time airframe tracking out of the hands of airlines and fitted / retro fitted the necessary comms systems as standard. Sure, it would cost them some money, but it would be a clear message to the flying public; MH370 could never happen again, not on Boeing or Airbus planes. And of all organisations on the planet, they’re the ones best placed to push that through quickly (the aviation authorities would spend years discussing it).

        (Thanks for the articles once more)

      • I’m sure that BA realise they have to be as open, and transparent as possible to regain trust.

        They’ll face all sorts of restrictions on what they can, and can’t say relating to the Lion Air, and Ethiopian Airlines crashes as there are on-going investigations.

        BA have a very fine line to tread over the coming months, and perhaps years.

        Given all that, I agree Muilenburg went further than I would have expected.

      • What are the specific things that stand out for you Scott? You mention the use of “own”. Any other words, phrases etc used that haven’t been before or weren’t that have been used before? Anything else (length of release, 1st/2nd/3rd person etc.)? Basically any clues as to who their main audience was in the video, how they might be positioning themselves etc.

        • Was it McNerney that put out the “We are moving to Charleston becuse of the union” ?

          As that was a complete violation of the NLRA, I tend to think he did not vet it so who knows?

          Hard to think of a more tone deft person than Muilenberg presented.

      • Scott, if you allow me, I have one correction to add. The Eastwind Airlines 737 incident did not occur at cruising altitude. They were at around 4000 ft in their approach, but it was still earlier in their approach compared to the United and USAir crashes, so they had more airspeed and hence there was more airflow for the other control surfaces. Also, the captain did something brilliant – he used asymmetric thrust.

    • Agree with Scott. The tone of voice was very different from the statements just after the crashes. The self praise & latent guild sharing was mostly out.

      They have too, because they realized public perception determines stock price in this case too. Looking stubborn & arrogant thus reduces his and his colleagues salaries.

      Some humbleness and honesty was overdue. Well done.

      • Others have noted the change in Boeings tone from the initial comments.

        ““Their comments have been very engineering-esque,” said Richard Levick, founder of Levick, a Washington crisis communications firm. “There has been no human face to this.”

        Because Boeing isnt a consumer company like an airline its a ‘business to business’ company

        “But after that hectic week following the Ethiopia crash, Boeing turned to Sard Verbinnen, a crisis communications firm based in New York that it kept on retainer, for assistance. What followed was a more assertive posture by Boeing.
        On March 18, Mr. Muilenburg released a statement and video expressing regret for the crashes and emphasizing Boeing’s commitment to safety. Days later, Boeing took out full-page advertisements in newspapers including The New York Times, The Washington Post and The Wall Street Journal.

      • Public perception won’t determine stock price, sorry; cash flow will. This will materially impact cash flow this year, period. That’s what is driving the change(s).

        And I’d also contrarily argue that if they’re taking a bath in earnings/cash flow short term, it makes launching the NMA MORE likely, as it means that the short term impact of that program will not be an immediate hit (the 737 catastrophe will already be priced into the stock price by summer). It’s stock buy backs that will be cut; the insiders will already be shorting.

        • I’m with you an that. It makes the NMA more certain, the cash flow effect of that isn’t much in the scheme of things for Boeing…..if the project runs off the rails in the future then all bets are off.
          Muelinberg won’t be the one to lead the business, maybe they will get someone with a strong background in BCA to run the shop in Chicago…promote whoever’s running the 777X right away. Doing what they had been doing before…sales and marketing or engineers who spent all their time in Defense & Space can’t continue

    • Hi Scott

      Thank you for your more than comprehensive coverage (as always). I don’t doubt that you see this as a major departure from the norm. At the same time to me it is clear that Boeing senior management are still guilty of being less than frank. As the Exec Chair Deny (autocorrect oops) Muilenburg is too concerned about saving his own skin.

  5. Sorry, I just don’t see a major shift in tone. The weight of evidence and investigations is so heavily against Boeing and the FAA that anything other than saying sorry (in some form) wouldn’t have cut it. But what did Muilenberg actually say…

    1) at 0:52, “MCAS, activated in response to erroneous angle-of-attack information”. At no point in the video does he refer to the way MCAS has been implemented thus far as ‘erroneous’. To me this smacks of sharing the blame as freely as he can, to potentially the AoA sensor manufacturers & designers.

    2) at 1:13 on, “erroneous activation of the MCAS function can add to what is already a high-workload environment. It’s our responsibility to eliminate this risk. We own it…”. Stating the obvious as MCAS is, as I understand it, a wholly Boeing ‘designed/manufactured component’. But again worded to deal with activation of MCAS, not with how MCAS then functions.

    3) at 1:24 on “from the days immediately following the Lion Air accident, we’ve.. (been) ..working tirelessly with the Federal Aviation Administration and our customers”. More generous blame sharing, this time for the FAA , airlines and leasing companies for months prior to ET302.

    4) at 02:13 on “along with the associated training and additional educational materials that pilots want in the wake of these accidents” implying that pilots didn’t want this before the accidents. More generous blame sharing, this time for MAX pilots who it seems didn’t seek such materials beforehand.

    and so on…

    • @Woody – You’ve really hit the nail on the head with Mullenberg’s blame-shifting rhetoric. I wish there were someone who’d call him out on TV or one of the big newspapers for precisely the things you’ve pointed out.

      • Second that. This speech was written by lawyers, not by someone who is really concerned about his customers, be it airlines, pilots or passengers.

        To begin with he did not admit the 100% obvious fact that the MCAS software is crap. The whole setup with the MCAS depending on one AOA sensor is crap too. Hiding the system from pilots was completely nuts. Not training the pilots on this system is unexcusable. Where is the “mea culpa” for all this?

        But the elephant in the room is the questions of why is there something like an MCAS in the first place? Not a word about it. Why? Because Muilenburg would have to admit that the MAX is fundametally flawed and inherently NOT SAFE!

        • Gundulf: Most is not in disagreement.


          Unless you make the case that the manual trim is a flaw (and I would agree its an open issue) then I don’t agree with your statement and its not supported by any data to date.

      • Well, Muilenberg’s potential co-opting of the AoA designers/manufacturers may have some validity and of the FAA appears to have validity. Maybe the rest to some extent too. Even if Boeing really were to stick their hands up and say “it’s mainly us” (and looks to me as though there is almost no chance of this now, given this video and the finance CEO heavy new committee) their shareholders could quite reasonably take them to task if they don’t seek to share blame if/where it genuinely ought to be. So I assume that they’ve done the calcs and worked out which approach will lose least monetary value and they believe it is this. I’m not convinced.

        What this video plays like for me is an out of touch, legal led one. Whoever scripted it knows that what a lot of people really want when they suffer harm is an apology. Often just that, no money etc.. But in this video he has managed to say sorry without really attributing that sorrow to Boeing. Or himself. Maybe he’s thinking of potential jail time and has chosen his words accordingly.

        • Thirded.

          Re: co-opting the AoA sensor manufacturer; the only hard evidence is that the FCS acted on (and the FDR recorded) duff AoA input. The opportunities for fault locations that could cause that come in at the FCS software itself back towards the A0A sensor, incorporating the device driver, interface electronics, wiring through the airframe, connectors at either end of that, and finally the AoA sensor itself.

  6. Boeing mess up the MCAS system. Mr UWE is there anything the USA does right in your world. Like it or not the USA is the leading aerospace country in the world and Boeing is in the forefront of that. I did not bash AIRBUS when a crash of their airplane was the manufacturable fault. I can remind you of several incidents that can be blamed on both OEM.

    • “AIRBUS when a crash of their airplane was the manufacturable fault”

      Just to be sure we are talking about the same stuff: could you enumerate?

      “leading aerospace country”
      Historically advantaged, war spoils and size. anything else?

    • @Daveo Just curious, which are those accidents you mention that were squarely Airbus’s fault? And if they exist, did Airbus blame everyone else but themselves?

    • I’ve just watched again and he dosnt seem to be that sorry. Perhaps Boeing could have made it easier for particularly dumb pilots, etc.I am absolutely certain that Boeing and the FAA are hiding a lot more information.

  7. An Auto maker with a problem can have huge exposures as well as extensive and on going lawsuits. Thousands of injuries can be attributed to Air Bags, Marginal Tires, Exploding gas tanks etc.

    An aircraft maker has a very limited exposure (and its fully understood that to the people involved its not limited exposure)

    Boeing could give each family involved in this 1 million dollars and be off the hook forever (no repeats, its going to get fixed) .

    Frankly the insanity of it all is stunning.

    And that

    • I’ve read that the Lion Air dependents got $58k… and signed away their rights. No idea if that is real or fake news.

      • I think that is about the average payout in an air related death isn’t it? Somewhere between US$50k and US$100k per.

        Can’t see the Ethiopian payouts being like this though.

        • Montreal Convention on compensation when there is a crash.
          But that doesnt cover cases where negligence has been proven. The lawyers will be coming after Boeing ..in US courts

          • Precisely.

            Re the US$50k to US$100k range I have in mind, it was a figure I read some time (years I guess) back and seemed to suggest to me that almsot all crash victim payouts are prescriptive. Easy enough to do in the case of Lion Air soon after the crash I guess, if this is what actually happened.

            If there genuinely was a Lion Air payout but it came after Boeing (and possibly the FAA) had recognised MCAS’ strength as contributory factor (I guess indicated by the date they started work on MCAS 2)…..

  8. Suddenly there is a shift in tone.

    Sounds like me like a two year old. No, no, no, until pictures are produced and then I am sorry.

    Unlike the Lion and Ethiopian pilots Boeing had plenty of altitude to maneuver with and LOTS of PEOPLE telling them it was c coming and (finally) began to pull out at the last minute.

    Obviously the board told Muilenberg he had to throw himself on the grande.

    Notice its Boeing that owns this, not the CEO.

    Notice the contrast with Ford that came out and said I don’t care what Firestone does, we are replacing the tires and then actually did it.

    Just a matter of how soon they retire him.

  9. Thanks for the US Air 427 link. Extremely well written. The ‘chain of events’ logic seem to apply to both Max crashes.

  10. AF447. AA587 vertical stab. A320 into tree at air show. You want me to continue.

    • A320 into tree at airshow?
      Look it up, they [highly experienced captains] were flying down to 30-35 ft above ground at a very low airspeed and high angle over a minor grass airfield surrounded by a forest.
      If you are below the height of the surrounding obstacles bad things happen. Minimum height for such flypasts was supposed to 170ft. agl

      • In this case instead of allowing a bump up, the protection system refused. Hard telling if they could have avoided the trees or now.

        “The crew applied full power and the pilot attempted to climb. However, the elevators did not respond to the pilot’s commands, because the A320’s computer system engaged its “alpha protection” mode (meant to prevent the aircraft from entering a stall). ”

        The whole thing was stupid all the way around and an incredible degree of arrogance in the French aviation community from Airbus to AF and the pilots.

        • Thats not what its says.
          The ‘system’ needed the configuration to be that for the maximum climb rate surely you understand that – normal usage would be for GPW warning to pull up. But as they were down as low as 30 +ft the engines couldnt spool up in time to impact trees which were higher than 30ft.
          I dont see why it was Air Frances problem when cowboys pilots take their plane below recommended minimums for fly by.

          Best comparison was the Emirates 777-300ER in 2016 when pilots wanted to ‘go around’ after wheels had touched the runway. I think it was a Boeing software design that didnt allow full go around power after the wheels have made contact with runway. oops

          • Duke:

            I am sorry that you don’t understand aerodynamics.

            There is an inertia factor that you can use at times.

            Read Fate is the Hunter and avoiding the Taj Mahal.

            In this case the system looked at the setup and said NO.

            There should be an allowance for a short YES, then revert as its totally true that long term Envelope Protection is better than pilots can do (not true in manual aircraft but that is no longer the case)

            So Airbus, AF, both had this wild you can;t crash it attidu7e we have build the perfect machine.

            The French authorities should NEVER have allowed a passenger aircraft to BUZZ an airdrome.

            The whole thing was insane.

            A bit of pitch change might have bumped them up enough so the engine spool up could kick in.

            When a system is program for the average, you have not latitude .

            We had a tower built to 80mph wind standard (above the highest recorded).

            The crew called management who called the engineer and said ” the windows are bulging in ”

            Holy *&^% says the engineer, get em out of there, that takes 100 mph. They did.

            What happened?. Wind gust are logged over a (7 to 15 second period)

            Why? Because aircraft don’t respond to a less than 7 second continuous level.

            However, glass with large square surface fixed in a mullion sees a faster peak.

            So, yes the gust were over 100 mph, they just were not logging that way.

          • You still havent got it. Airbus cant possibly build in a low and slow mode for forests.
            The result the pilots wanted was what you would expect if coming into land on a runway and pilots request a go around as said on the FVR tape (Translated from French)

            Capt:OK, I’m OK there, disconnect autothrottle
            F/0:Watch out for the pylons ahead eh See them ?
            Altimeter ‘Forty’
            Capt:Yeah, Yeah, don’t worry
            Noise of power lever indents ‘clack clack’
            this is when the radio altimeter starts saying ‘ thirty’
            F/O :TOGA/SRS ie ‘Takeoff/Go-around , on Airbus aircraft it is activated by pushing the thrust levers fully forward to the TO/GA detent. ( the clack clack)
            F/O:Go around track
            Capt: Sh…

            5 secs from noise of power levers being moved to noise of tree tops impacting the plane
            they werent over a runway, but forest, which the plane proceeded to to a ‘soft landing’ on.

            Airbus and Air France wouldnt approved the pilots to go so low but they werent asked .End of story.

          • Well it makes nice reading, but misses the fact that the Envelope Protection on Airbus can and had lead to its own set of issues.

            So you can wrap it up in a nice fuzzy bundle in your mind but that does not make it so.

            And Airbus was touting Envelope as an end all and be all. The Captain drank the purple coolaid.

            And a bump up would have allowed spool up, enough? YOu would have to model it.

            Airbus subsequent got less exuberant about you can fly in canyons and such and live to tell about it.

            And it does not matter if its 100 feet, or 200 or 40 feet, you don’t take passengers to airshows and buzz the place.

            You might read the regs on aerial displays in Europe now, a lot of people have died when they let so called experience aviation do stupid things around airshows and some just plain failures.

            No one gets a pass on that stupid into the trees A320. It should not have happened and that does warp it up.

  11. Mr. Bobek there were two crashed A300-600R of China airlines that was OEM related fault. Every accident in the end advance the safety of aviation and Boeing is at fault in the max situation. They arguably are the best aircraft builders around and to refer to them as a fly by night outfit is unwarranted. Mr. Uwe have never posted anything good about the USA whether in this forum or other medium. I own stock in BA and EADSY. My main interest is the advancement of safety in aviation because that is how I make my living. I fly on any Airbus and Boeing aircraft all the time and have no single doubts about them.

    • you make a reasoning error.
      fairness is not “cussing both parties equally in an environment of asymmetric cause for cussing.”

    • Mr. Bobek there were two crashed A300-600R of China airlines that was OEM related fault.

      wrong training and an update not applied yet by the airline.
      Airbus fault obviously.
      The report concludes by pointing the finger at China Airlines for what it calls “insufficient training” and “poor management of the resources in the pilot’s cabin”
      Airbus fault obviously.

      Can you cringe or are you beyond Boeing 😕

    • @Daveo It’s bobec, not bobek. It seems you either are not knowledgeable enough about the subject, or you are simply driven by your self-interest of protecting Boeing’s stock performance. Who is the best airplane manufacturer is a completely subjective issue. You can have your own opinion, but that doesn’t make it a fact.
      None of the accidents you mention are OEM-related. The China A300 crash and AA587 are 100% pilot error. So was AF447. The “A320 into trees at an air show” is pilot error, plus negligence, poor planning, etc. I think you would benefit from reading about those accidents, and then maybe you wouldn’t be making such false statements.
      OEM-related crashes are the Comet, the Lockheed Electra, the 737 rudder problems, the DC-10 door blow-outs. Probably the United DC-10 crash-landing (though there was a manufacturing defect in the engine, once again it was proven the DC-10 was an unsafe design with a crappy hydraulic system). Shared responsibility – AA 191 – outdated procedures which advised the crew to reduce airspeed, dangerous maintenance procedures, which McDonnell Douglas had to hire a private investigator to find proof of, eventually the FAA catching AA in the act of destroying evidence (looks like McDonnell Douglas do know the system of corner-cutting and one would do when they are about to get caught), and once again, the crappy DC-10 hydraulics which left the crew without slats on the left wing.
      Now I wouldn’t go bashing the US left and right, if this is your concern, but Boeing, and many US corporations have a history of cutting corners, downplaying hazards which they knew about, and putting people’s lives and safety in jeopardy. Even worse, regulators have been unwilling or unable to instill proper checks on corporations.
      This is actually bad for the US. The 737 MAX should have been grounded after the Lion Air crash. Boeing, and the FAA, kept stonewalling well after the Ethiopian crash. What does this mean? It means the FAA has lost its reputation, and hence its influence around the world. Don’t expect the Chinese to accept an American made plane as safe, just because the FAA said it was. Or even other countries where Boeing sells planes. You don’t understand how much damage your beloved Boeing has caused to our country. I would prefer to have the US as a world leader, but if that means more fiascoes like the MCAS debacle, then maybe it’s for the better for the world if we no longer lead (what Trump wants anyway). It’s exactly because of the power of shareholders that all this has happened – from designing the 737 MAX this way, to keeping stuff about it secret, and then fighting the pressure to ground it. I believe the power of shareholders in the US is way too much and it forces manufacturers to behave in a way that puts their interests first. This in turn leads to short-sightedness and a total lack of vision. Just like with trying to impose tariffs on the CSeries. This system of corporate governance is totally out of balance and needs to change.

      • bobec:

        Some fair points, but fly by night?

        And have you found a system any better?

        The ugly reality is this goes in cycles, look at Maconda.

        So yes Corporations have far too much power, you put regs in place and they start to whittle away.

        On the other hand, there are places you just disappear.

        Do you truly think State Actors like Russian aerospace and China aerospace are a good answer?

        • @TransWorld Oh no, this isn’t exactly a critique of capitalism or left-wing blabber – though all those terms can mean different things to different people. State ownership is definitely not the answer. As a side note, there capitalism comes in many varieties. All I am saying is you need proper regulation (not necessarily more), transparency, symmetric information, etc. In school they teach us about the “free market economy” and that it’s the best system because it is the most efficient and beneficial one as a whole. What happens when those free markets are distorted? It doesn’t have to be just the state that distorts. It can also be a very big corporation of high strategic importance (or a whole industry colluding together) that manages to corrupt the regulation and certification process, and all the economic and regulatory checks and balances that should make sure no one has a free reign with the lives of the consumers and the general public, or their safety – as shouldn’t the state itself.
          But other parts of the system work – for example, investigative journalism. Now let me just speculate wildly – I don’t know if this would have been exactly the same had Boeing remained 100% loyal to Seattle, as there has been some friction, but anyway they are still very important in Seattle.

          • ” In school they teach us about the “free market economy” and that it’s the best system because it is the most efficient and beneficial one as a whole. ”

            Jerry Pournelle SF-Writer and Paleo conservative once wrote that uncontrolled market economy would have human meat and children as merchandise in no time.

            That Grail like fiction of an “unregulated market economy achieving perfect economy” does not represent reality. And this “fake” systems starts to turn destructive when internal pressure can no longer be relieved by expansion. Without expansion it just concentrates wealth in few hands.

          • bobec:

            As Greenspan once said, you guys are showing excessive exuberance .

            Free capitalism is likely (if allowed) as bad as a dictatorship.

            Society and business need to have regulation to make a system work .

            Free capitalism is more accurately unrestrained capitalism and in that case everyone should drive on what ever side of the road they want.

            Ergo, yes we need regulations and well done good regulations are not the same as excessive.

            Sadly the current setup encourages tearing down those regulations.

            Those in turn can lead to worse than the two crashes.

            I think we agree on a lot – we need more AOC’s to keep the light on the slime

        • ?? Maconda.?? lead me!

          The US system is vampiristic. Without the Petro Dollar and its Toll like property for international trade the US would long be broke.

        • “On the other hand, there are places you just disappear. ”

          You are talking about extra legal renditions by US services 🙂

  12. Wasn’t AA587 due to the highly skilled pilot stressing the rudder way beyond its design limitations?

    • Not when you are limited to watching “Air Crash Investigation” or similar foxy stuff.

    • Excessive rudder usage
      Probable Cause
      “The in-flight separation of the vertical stabilizer as a result of the loads beyond ultimate design that were created by the first officer’s unnecessary and excessive rudder pedal inputs. Contributing to these rudder pedal inputs were characteristics of the A300-600 rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Program. ” -NTSB
      FBW envelope protection on newer planes wouldn’t allow that to happen now.

      Interestingly there was some dissention amoung the NTSB board
      “Members Carmody and Healing voted against the Vice Chairman’s revision, which reversed the
      order of the two contributing factors shown in the staff draft report. For more information, see the Board
      Member Statement that follows section 4, “Recommendations.”
      Essentially the AA maneuvering training program was in the gun.
      “When questioned by a captain for using the rudder in an earlier incident, the first officer “insisted that the AAMP directed him to use the rudder pedals in that manner.”

      • Actually it was a three step failure.
        Airbus designing a “light” rudder 25 years earlier.
        AA instructing pilots overriding caveat/nogos by Airbus
        The pilot being the type of the “high amplification, large inputs” machine user.

    • Roger: This extends even rather, its the regulations.

      Like a lot of the envelope protection stuff its some and some.

      In this case they said not to do it, there was no “software” to inhibit it (which is an MCAS function) and so it did not have variable steering equivalent.

      Pretty much if the mfgs say we can’t do it, then too bad.

      So you can whack off your Rudder (and a bit hard to know when to quit if you get excited !) but you can’t stall it (but it dumps it in your lap when the speeds go whacky.

      Can’t do anything about blowdown, pretend it does not exist.

      Frankly it was what occurred to me that got AF447

      There is massive illogic there

  13. Actions speak louder than words.
    The world awaits for Boeing to:

    1) Compensate the victims fairly.
    2) Explain what realm MCAS is for, and if the MAX is aero-stable.
    3) Explain the fix to MCAS for the public to understand, at all levels of interest, the short version, the medium version, the detailed version.

    • Also exactly how it came to be like it was.Most new aircraft programs run into development problems that require a fundamental rethink,but I suspect that at various points in the development of the MAX engineers were told that simply wasn’t an option. Everyone was astonished at how Boeing had managed to execute the MAX to such a demanding timescale

      • Everyone had wondered why Airbus took such a leisurely approach to the
        NEO timing:
        Dec 2010 to Jan 2016 ~= 61 month
        Aug 2011 to May 2017 ~= 69 month

        • AB had the thing ready to go at launch and a lot less changes.

        • More related to ramp up of new GTF engines than the ‘minor’ changes to the A320 that were required.
          Airbus like Boeing had full order books out some years anyway.
          The 737 Classic was announced in late 79 with specs released at Farnborough( Jul) 1980. Fir5ts 737-300 rolled out Jan 84 and certf in Nov 84.

  14. Being missed is that Boeing did the same thing on the 787 program with the battery.

    It was shear luck that no one died in those incidents.

    Its not the MAX, its the system folks.

  15. Excessive rudder movement means the rudder was poorly design. Airbus went back and redo the hard limits.

    • Its a variable rate control As the plane gains speed the movement is limited to only small defections as you would expect.
      No one expected before or since that a pilot would swing it back and forward between hard stops on both sides just after takeoff.
      Airbus did use grandfathering on its design as the A300-600 (cert 1984) was a later model of the original A300. ( cert 1970)
      The later redesign was for the newer standards applying

      • Kind of like no one sees AOA failures like they have?

        Clearly some pilot did use pedal to pedal and I have certainly in smaller aircraft (it is the only thing that gets you out of a spin and at that point you got nothing to loose trust me)

        Now when I went back and red the counter spin for that aircraft it was slowly push in the pedal.

        One part of me was totally calm (after total panic) , I need to push counter rudder here.

        I am pretty sure I put a dent in the area under the pedal and likely would have no done anything else even if I knew I should (after practice yes, probably)

        You have to have data and what data did Airbus have?

        Boeing had data that said these failure were rare (bad data or ???) but they had some data.

  16. I never understood the proposed MCAS 2.0 ~5° differential as being the solution to prevent MCAS activation if an alpha vane fails. Yes, part of it, but: What happens if both apha vanes fail and show the same number. Say both alpha vanes failed and showed a value of 75°. Isn’t it a good idea to set floors and ceilings, setting a maximum delta, as per the Airbus FCC.

    To dream up a floor, a ceiling and therefore a delta. Floor: -20° alpha, Ceiling: +20° alpha, Delta: 40°. Anything outside of those numbers is rejected as invalid. Meaning MCAS doesn’t activate.

    If MCAS 1.0 had done something as simple as that, both the Lion Air and Ethiopian Airlines crashes would have been avoided. MCAS 1.0 doesn’t. In the Ethiopian Airlines crash MCAS 1.0 accepted a 75° reading from the left alpha vane. That is plain daft. It should have rejected it as just daft. The reading from the right alpha vane was valid.

    But it appears MCAS 2.0 will still accept daft readings and simply rely on a ~5° differential between the left and right alpha vanes. Why?

    Please note, I accept that floors and ceilings can – should – vary depending on envelope.

    My thought for the day. Time for coffee!

    • Interesting point, I have another suggestion. How about rejecting any reading that moves faster than the aircraft can possibly manoeuvre?It’s so obvious that there is probably a good reason why not.

      • Yep. Now we are talking. I think we need to define the flight control laws for Boeing. Having said that, there is a lot more to it than we are saying. But there nothing wrong with starting with the simple stuff.

        In truth, Boeing need to do some headhunting for they are clearly not experts on FCCs . BAe are world class experts on FCCs. Perhaps Boeing and BAe should team up.

        • Philip: Yes there should be non allowed limits.

          If it comes up outside those it posts Unreliable and the program can then be set to take or not take o9r not continue actions.

          While a help, its pretty miner in the scheme as the possibility of two AOA having a disagree and the same data is off the charts.

          Good controls programing yes, not the core of the issue nor main protections.

    • Can I make clear the reason for my post. The envelope. Floors, ceilings and deltas cannot be set without knowing the envelops. What Gubbie said is determined by the envelope.

      We now know that Boeing didn’t test invalid sensors or simulate invalid sensors. We now know the elevators become inoperable. We know know manual trim becomes inoperable. Floors, ceilings and deltas aren’t present in the FCC.

      The big question is pitch stability. MCAS was developed because of sensitivity to pitch caused by the engine/wing mounting. Have they tested it.

      My big concern is clear air tubulence, especially on climb out. Many forms of clear air turbulence are opaque to weather radar. The turbulence can be very, very rough. Will the airplane servive if the pilots use a high AoA while traveling through turbulence they carn’t see?

      • Philip:

        Simply put, no matter how rough the aircraft is not going to see an AOA approaching stall.

        Its only at stall does the pitch up occur.

        Aircraft operate far from stall even in the roughest weather.

        Turbulence is not the same aeyr8anly as a high AOA.

        Unless there is data to say otherwise conjecture adds nothing to the conversation.

        I can conjecture little green men will visit me and give me a million dollars and I better not spend it before they do.

        WE call it putting the cart before the horse.

        Get facts, then assess.

        Facts may come out (and continue to do so)

        I for one am not the least bit happy the backup trim (manual) is hard to impossible to use.

        That has not been an issue until now but it certainly should be a consideration.

  17. I don’t have any confirmation, but I think what might have contributed in Boeing going after the MCAS solutions was a similar issue earlier on. It was solved by a software fix a few years before, the 747-8 wing tip flutter.

    The re-engine and extended tip of the 747 created new wing dynamics that led to a slow resonance, flutter, at the wing tips at certain speeds / AOA’s. It showed up unexpectedly during test flying, late in the test & certification process. Flutter could never pass FAA certification. A structural solution would costs a lot of time and money..

    A smart software fix saved the day, actively compensating the flutter (with the new fly-by-wire outboard ailerons) compensating when flutter occurred. Solved, certified, everybody proud (Engineer of the Year), happy end.

    That success must have motivated Boeing when the pitch showed up during the 737 re-engine test flights.

    • Yep, but it did require high speed/high precision servo-actuators to do it. Luckily they were already installed because of the new flybywire alierons.

      They could have treated the 737 as a relaxed stability airplane. But it does require quick acting stabiliser/elevator actions that in turn require high speed/high precision servo-actuators.

      Another option what have been to use slight flap extensions. But, again, servo-actuators?

      The reality is they needed to address the stabiliser/elevator. It should have been resized as well as ensuring the elevators remained operative and manual trim remained operative. They could have added wizz-bang servo-actuators. But it would of cost more.

      One thing that got me is that showing the AoA on the screens is an optional extra. The air speed, altitude and AoA in my view are the three most important pieces of air data. As they say, you live and learn

      • And what happens if your anti flutter system goes South?

        Actually the initial move was to not let them use the tail fuel tank which kept the -8 out of flutter.

        Telling pilot not to stall the 737 MAX would have worked fine as well.

        • > Telling pilot not to stall the 737 MAX would have worked fine as well.

          Except that pilots do inadvertently come lost to stall and the feel of the Max as it approaches stall “tells” the pilot the stall danger is easing off.

  18. Something is off on the MAX, that it requires MCAS. At higher AOA, the wakes of the higher located turbine nacelles may affect the flow at the elevator, reducing its effectiveness. MCAS may be needed to provide the necessary moment to get the nose back down. Increasing the size of the elevator would be a major structural redesign and would lead to higher drag.

    • An interesting point HPBNA.

      Have they never changed the size or shape of the stabiliser, or elevators from the original 737-100 through to the 737 MAX-10 ?

      I would have thought they would have changed them over the years as the MAX-10 is a little over 1.5 times the length of the 737-100.

      I’d be interested to know what the airflow over the wings directly behind the engines is doing at high angles of attack. I would imagine it’s pretty turbulent.

      I wonder if there’s any loss of lift at high alpha ?

      • Span of stabilizers changed from 36ft on 737-100 to
        to 41 ft 8 in on the classic to 47ft 1in on NG/Max

        • I continue to wonder that someone throws out a totally unsupported idea based on conjecture only.

          It does not mean there are not issues, but all that was reviewed by the FAA flight department in actually test flights by THEM.

          Its part of the process.

          I am not buying there is bizarre other affects.

          Granted Pink Aliens with Purple dots will visit Renton tomorrow and fix everything.

          • Given that it has been reported until the Lion Air crash the FAA thought that MCAS only moved the stabiliser 0.6 degrees, and not the 2.5 degrees that BA stated after the crash.

            Given that they didn’t know, or were happy that MCAS relied on only one AOA sensor, there are bound to be questions about what else the FAA didn’t know, or didn’t check, thought was ok, or took BAs word for.

            “Its part of the process.” yes but the process failed, in the interests of safety questions need to be asked, and indeed they are being asked. The DOT audit of the certification of the MAX 8 will hopefully answer a lot of questions.

            From https://www.theatlantic.com/notes/2019/03/heres-what-was-on-the-record-about-problems-with-the-737-max/584791/

            regarding ACN: 1593017 – 737 Captain

            “I am left to wonder: what else don’t I know?”

            This statement which has been widely quoted is the key point, until trust is restored, there are going to be questions.

        • @Dukeofurl

          Thank you for the data. I would have been quite surprised if they hadn’t got bigger.

          • Remember , the horizontal stabilisors work on a moment arm, longer planes get more effect from same area.
            I think it was the MD11, which was a big stretch , had smaller tail surfaces.
            The largest moment required may be the rotation at takeoff, when you are low speed but want the most movement of the nose of the plane. A ships rudder is the opposite , its tiny but by turning the hull slightly the water flow against the hull does the rest…slowly.
            Things happen quicker with planes

          • @Dukeofurl

            A good point “the horizontal stabilisors work on a moment arm” I assume that’s why the testing of MCAS 2.0 is/was being done in a MAX-7

    • Turbulence caused by the engine/wing mounting over the stabiliser is a very good theory. Given the lack of a pylon there’s going to be one hell of a wake.

      • Maybe, but what I’m interested in is the airflow over the wing, i.e. is there a degree of lift lost due to the turbulent air over the wing right behind the engines.

        I suspect that at high alpha the stabiliser would still be in clear air, hence you’d be able to use a strong nose down pitch to counter a pitch up.

        If the aircraft was at a high angle of attack so that the nacelles started to generate lift, and turbulent air over the wing directly behind the engines were to cause significant loss of lift, I would think your rate of change of pitch would accelerate ?

        This is not a MAX specific interest, just general aircraft design. Although I would expect the effect, if there is any, to be greater with a MAX like design.

        • Again, yep. It’s all about base aerodynamics. Base meaning behind a body, in this case the wing. The effects are propagating upstream, affecting the rear section of the wing.

          So yes, above the rear section of the wing but also below the rear section of the wing. The net effect is to move the CofL forward, making the airplane sentitive to pitch.

          This then comes to the nacelle. I think the nacelle is causing lift at all alphas. The reason is that it is so close to the wing that it is extending the mean chord of the wing foward. In other words the nacelle is part of the wing.

          But I do agree that the lift ptoduced by the nacelle increases with alpha. This causes the pitching moment to accelerate with increasing alpha.

          That’s why MCAS was wriiten. Specifically MCAS has the job of stopping the pitching moment before inertia caused by the pitching moment means it can’t be stopped before a stall occurs.

          This then comes to stopping the pitching moment. The trim stabiliser is used. Why? Trim stabilisers are not fast acting/fast moving. The fact that MCAS uses a 10 second action proves that. The 737 MAX trim stabiliser doesn’t have wizz-bang high speed/high precision servo-actuators. So moving it is a bit slow. Hence, the 10 second action.

          But then trim stabilisers are not designed to manuever airplanes away from stall. They are designed to mildly trim the airplane allowing the elevators to remain in a neutral position. So trim stabilisers are not designed to be fast acting/fast moving

          Elevators are designed to manuever airplanes. So elevators are designed to be fast acting/fast moving. As I said long ago, elevators manuever airplanes not trim stabilisers. Why doesn’t MCAS use the elevators?

          Anyway, let’s see what outside regulators think. They aren’t going to just believe Boeing and the FAA.

          • This all getting too complicated for me, but maybe MCAS isn’t designed to keep the MAX away from stalling, but to try and keep the elevator feel the same.Boeing is going to have to fess up and tell us what’s going on or it won’t be recertified and I won’t board a MAX.

          • Grubbie:

            Some of the wildest conjecture coming out yet. That is what may be confusing, its sorting out who to listen to. You have to educate yourself and see what tracks. Opinions are not facts.

            Getting into all the system details is complicated but the simple reality is that the 737MAX as is approached stall had a pitch up tendency that was not acceptance per the regulations.

            The other tidbit evolves around STALL. You don’t want to stall so your remedies occur just before stall. I don’t know EXACTLY what point in this the pitch up occurred, nor exactly what point they set to intervene. Suffice to say its not to let it stall so you intervene before that (1/2 deg, 1 deg, 2 deg?)

            As this was not seen on the modeling (flow models) it was unexpected, but you can update your models (and that is what test flights do as well as find issue like this)

            At this point the speculators go running around like chickens with their heads cut off carrying on about CL, CG, wing stalls, moving forces etc. Those same people do not have ANY DATA.

            You need to have the models or the actually test data to see what is occurring, has occurred.

            That is where failure began, the intent was to give a nudge down as you hit that “stall” are you wanted to stay out of.

            This would have done two things, kept MAX feeling like the NG as well as not allowing that nudge up to make it worse.

            Nothing more than that. Pretty straight forward. A320 will have handling aspects different than an A330 but they make them the same feel.

            Now WHY Boeing decided to give the stabilizer such massive authority vs what was discussed/presented to the FAA which was much lower level is still to be found out.

            It would have been tested and with the AOA working right as soon as it came down out of stall region it would have stopped and the FAA would have said, yep, that works, good. Those are FAA test pilots.

            What was not done was a review by FAA controls specialists (if they have any anymore) and looked at the software, how it was assessed, its possible failure modes. That was all Boeing’s doing.

            At that point we know what they did and that was class it as not enough criticality level (1) to require redundancy in inputs.

            We know they gave it massive authority on the stabilizer that cascaded into not being able to utilize the elevators to counter and messed with Boeing philosophy you can always override systems (full back on the yoke should make it stop)

            The wild speculation (they are not theories, theories are backed up by some facts that lend themselves to a supposition that is tested)

            Darwin is the Gold Standard. All those finches that all had different beaks, hmm, what could explain it.

            Wild speculation (voodoo) on the other hand is ” We threw a Maiden into the Volcano, it quit volcanoeing , ergo, throwing Maidens into Volcanoes makes them stop.

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