Indonesia grounds MAX, one-third of world fleet now grounded

Update: Royal Air Maroc, Mongolian Airlines ground MAX.

March 11, 2019, © Leeham News: Indonesia regulators today joined China, Grand Cayman Airways and Ethiopian Airlines in grounding the Boeing 737 MAX pending investigations or inspections.

This means about one third of the in-service MAXes have been grounded by regulators or operators.

The moves came within 36 hours of the crash of Ethiopian Flight 302, a MAX 8, six minutes after take off from Addis Ababa. The crash killed all 157 people on board five months after a Lion Air 737-8 crash that killed 189 passengers and crew. Lion Air is an Indonesian carrier. The airline’s JT610 crashed 12 minutes after take off.

Similarities between two accidents

Initial flight profiles from Flightradar24 showed some similarities between JT610 and ET302. The former reached an altitude of about 5,000 ft; the latter climbed only about 1,000 ft. Both flights showed erratic speed readings and altitudes. Both apparently nose-dived on the final descents. Pilots of both aircraft reported difficulties and wanted to return to the airport.

The Lion Air flight data recorder pointed to MCAS, a software programming that is designed to provide protection against stalling. MCAS has not definitively been identified as causing JT610’s crash; this investigation continues.

Flight data and cockpit voice recorders from ET302 have been recovered but not yet analyzed.

Software fix

After information in the JT610 accident initially pointed to MCAS, a software upgrade to the programming was discussed. However, two sources tell LNA that no upgrade has been implemented yet.

In the absence of a definitive finding that MCAS was responsible for, or substantially contributed to, the JT610 crash, proceeding with the discussed upgrade hasn’t happened.

Additionally, any upgrade requires validation and regulatory approval, the latter being often a slow process.

Investor reaction

Investor reaction in pre-market trading has been to drive Boeing stock down nearly 10%. This was about the same as following JT610’s crash.

Boeing stock was depressed for several weeks after the Lion Air crash. The full implications of ET302’s crash won’t be known for some time.

Boeing’s production from the 737NG to the MAX is nearly complete. There are fewer than 50 NGs left to build and deliver.


122 Comments on “Indonesia grounds MAX, one-third of world fleet now grounded

  1. As far as I remember one problem on the Lionair case was, that the AoA sensor was sending wrong values and so triggered a reaction from MCAS, when no reaction was needed. It was reported, that MCAS uses only the values of one AoA sensor (left or right – depending on who has the command in the cockpit). If the reporting is correct, it seems there is zero redundancy at this point?

    Does it not make sense to deliver a software update, so that MCAS uses all available sensors/data to prevent a terrible reaction just because of a single faulty sensor? So a software update would improve the system no matter what the final findings in the lionair report are.

    Could you clarify this?

    • Not much clarification needed.

      It was a stupid thing to do and stupid implementation and stupid to not train pilots let alone have an displays clearly stating out of servicing and a way to disable it.

      You put a override piece of software in a system (nothing should ever overridden a pilot) and not tell anyone and make the displays of what the critical input (and use only one) as options.

      Its a slow system to react and Boeing gets off cheap, its just chump change to them.

      When you kill 150 people (first time) you impact 1000 lives.

  2. This might grow, not least in the public mind: I have seen several articles in web and print media calling the 737-MAX8 the “accident model”, the”crash plane”, etc. The exact wording differs a bit depending on language, but are more or less similar. Evening papers as usual a bit more sensationalist, but if this keeps itself in the headlines a few days more Boeing need to show decisive action to avoid a PR disaster, one that it can ill afford for its moneymaking stapel model.

    FAA might feel the need to show it has a grip on the issue, so would not be surprised if some statement or action comes in the next days.

    Will be looking at what Norwegian will do in the next days, might be a good indicator of what airlines will do/need to do to keep their public image intact.

    • To be clear, there is nothing sensationalist about these types of headlines. This is no longer a case of coincidence or “bad luck.” The MAX has now definitively proven itself to be significantly less safe than its contemporaries (NG and all A320 models). It still looks okay by 1960s standards of aviation safety, but those are not the standards we expect today. The world has changed.

  3. Quite disappointing that the FAA is behind the curve on this. There seems to be a considerable reticence to act unless something happens in the US and they are absolutely forced to. This is especially the case when it comes to upsetting Boeing. We had the unwillingness to ground the burning B787s and now we have the slowness regarding the altitude delinquent MAX 8.

    The fact is we all suspect that there will be frantic lobbying behind the scenes by Boeing to stop a grounding happening. When the Lionair crash occurred they attempted to push the blame onto the pilots and I think a lot of us were a bit cynical about that at the time but they got away with it. Now we have 157 more dead.

    We could do with a detailed and wholly independent investigation of this crash to establish what has happened. I am not a conspiracy theorist by nature but as I understand it Boeing have sent their team out there to investigate. Surely there is a potential conflict of interest if Boeing have a chance of being culpable?

    I sincerely hope that something good comes out of this but at present there appears to be something fundamentally wrong with the controls on the MAX 8 just from the first crash and if there is any suspicion it is a chronic design issue then it should be grounded.

    The use of MCAS to mask a known design weakness seems really foolish in retrospect. The need to grandfather meaning they couldn’t adopt full FBW also seems a retrograde step. Full envelope protection of FBW would have had to have been more rigorously tested and in all probability this would have come to light as an issue.

    • I think every day the FAA / Boeing do not respond more questions arise if flight safety is really the #1 priority. The 787 batteries fire handling showed foreign authorities and airlines forced the FAA to take action, after everybody else.

      • Agreed.

        The FAA is conflicted because it has two roles.

        Support Aviation and regulate it (NTSB investigate accidents and has no regulatory powers…..

        Its long been contested that they should split the FAA into two entities and a price keeps being paid.

        The 787 batteries could easily have taken whole aircraft down.

          • Why bring this up as its no related in any way. It like the eyewitness thing.

            Its not uncommon. Provably about as common as engine failures.

            Don’t get me wrong, its a really bad thing and its extremely serious (note they got a replacement aircraft ?)

            Its also no remotely unique to the 787 and I would call it bashing (piling on with no relevance).

          • @ TransWorld
            You bet I’ll pile on. What you see with the handling of the 737 MAX program has a common cultural root with the 787 program disaster and the battery crisis. They figured it was okay to kick the can down the road so why bother actually do the work right. And smoke in the cabin, while may be relatively common, has a more severe consequence for a CFRP airplane (787): The structure is violently combustible. I maintain, this is something that was hand-waved at the time and we may yet come to revisit the issue, remember the Ethiopian Airlines 787 fire at Heathrow right after the battery fix? Whatever happened to that investigation?

    • You need to understand that the FAA views its primary mission as protecting the interests of the US aviation industry. You should not expect them to regulate safety except insofar as doing so is clearly in the interests of the industry. NTSB has significantly more independence, but no regulatory power, which is why you see them make post-accident recommendations that are often summarily ignored by FAA.

      • Interesting, is that why they have come down severely on RR and less so on GE and P&W when it comes to engine Issues? So a MAGA approach of nationalist competitive regulation?

        • I don’t know all the details there, but from what I’ve read the FAA was primarily just mandating what Boeing and Rolls were already recommending anyway. In that sense there wasn’t a tremendous cost to the regulation.

          • You are saying the FAA is over sensitive? I am thinking we have documented cause of CFM killing passengers but there seems to be double standards

          • No you are. It goes all ways and FAA does not do what it should because it supports industry. All of them.

            You think RR does not have a presence in the US?

            I assume you have heard of the CV-22 – C0130 and the C-27?

          • It was the 500 cycle between check service restriction on the stage 1 rotor of the IPC issued by the FAA that has cost Rolls-Royce $2 billion. Rolls-Royce did not recommend that restriction. The restriction means that engines are being checked 3-4 times a year.

            Given that there had been only one failure (out of ~500 engines) with a very high cycle engine (> 4000 cycles) the restriction isn’t warranted.

            When HPT blades started falling out of the back of GENX engines nothing like the above occurred.

            I agree with sowerbob, double standards

    • Looking back at a Nav 14, 2018 Seattle Times article by Dominic Gates, this stands out:

      “The fact that the plane’s nose could be automatically and repeatedly pushed down due to one false signal shocked Peter Lemme, a former Boeing flight controls engineer, who said it looks like a design flaw.

      ‘To contemplate commanding the (horizontal tail to pitch the jet) nose down clearly is a major concern. For it to have been triggered by something as small as a sensor error is staggering,’ Lemme said. ‘It means somebody didn’t do their job. There’s going to be hell to pay for that.’ ”

      An area for serious investigation if MCAS is even remotely implicated in this Ethiopian crash would be why MCAS could even activate. It is supposed to be disabled when flaps are in use. At such low altitude, so soon after takeoff, unless the crew somehow performed a flapless takeoff, MCAS should not activate at all.

    • The FAA is in the pocket of industry because they are directed to be.

      They are also regualry and safety.

      Its up the the lawmakers to correct this which they have not done.

  4. Can someone tell me exactly why a need for MCAS for the 737MAX 8? Thank you

    • @Conti: The bigger, heavier engines are mounted farther forward than on the NG and shifts the CG a bit. MCAS is intended to counter this in a stall.

      • @Scott: Does this potential issue impact it’s larger sibling, the 737-9? Or was the CG shift in the MAX 9 dealt with in a different manner?

        Another way to ask the question: was the MCAS “band-aid solution” also applied to the -9? Further, is the band-aid solution envisaged for the not-yet built/not-yet certified siblings (-7 and -10)?

    • The big LEAP fan cowling in front of the wing generates a bigger lift / pitch up moment. At low speed, the aircraft should automatically nose down to increase speed & prevent stall. MCAS automatically compensates the pitch up.

      • This of course is the same stall we are not supposed to be in and have plenty of warning its about to hit.

        And the warning is false as well – one AOA not two or redundant AOA on each side.

        Other than AF447 when has anyone stalled a commercial aircraft?

        • Other than AF447 when has anyone stalled a commercial aircraft?

          Does your stall question refer to pilot error, such as …
          * Colgan Air Flight 3407
          * Birgenair Flight 301
          * Pinnacle Airlines Flight 3701 
          * Turkish Airlines Flight 1951

          • Ref was large, Colgen was an ATR.

            What were the other 3?

          • And I looked up TK 1951.

            That was another automation induced issue along with possible pilot training. They did not simply fly it into a stall.

            I said other factors aside which include pilots no monitoring their approach.


          • Birgenair 301 was a 757-200
            Pinnacle 3701 was a CRJ-200

          • And what were the circumstances?

            I made it clear that an out of control and or other oddity does not count.

            No other factor was present for Indonesia crash other than the AOA and a speed issue.

            The ATR was icing up with a crew that was short on sleep.

  5. Having followed Bjorns thruogh analysis,I would have thought that it would be absolutely impossible that any MAX pilot would be unaware of what happened to lion air and not switched off the stabilizer trim if presented with a similar situation. Logically this suggests to me that either it’s nothing to do with MCAS or there’s another even more serious problem with it that is either undiagnosed or undisclosed. Having been certified with MCAS it can’t be possible to simply turn it off.It wouldn’t be possible just blame the crew either because the plane would have been proven to be prone to crew error and unsafe from that point of view.

    • Going last to first.

      That is what they said about locking cockpit doors after 9/11, oh no, we have to certify them.

      AK Airlines (as a result of a hi jack) had an in house desing ready to go, they simply installed them and defied the FAA to do their worst (which of course was not going to happen – they also gave the plans to others for free)

      There is a massive difference between hiding behind regulations and telling them to stick it and fix the issue and let the AIJ catch up.

      Top one: Read flight global on EA and then tell me it can’t happen.

  6. The 737-8 is just the base variant and yet it needed something such as the MCAS to make it behave normally as its predecessors. I do wonder what other ill-conceived features are being worked into the other variants, especially the 737-10, which is currently undergoing the heavy lipstick treatment to make it an attractive proposition.

    This dinosaur’s extinction is long overdue and Boeing should have had the NSA coming sooner.

  7. It may appear as if Boeing is in a precarious situation. A preliminary grounding of the MAX may become permanent if the automatic trim is unworkable. The only solution then would have to be a complete redesign of the aircraft. That would mean a new, taller wing-mounted landing gear mounted further outboard from the centre line of the aircraft — i.e. implies a heavily redesigned wing and centre section. Of course, if that would end up being the only option, Boeing might as well skip the NMA and launch the NSA in order to survive long term.

    If it looks good, it flies good — that’s what one typically says in the airline business.

    IMJ, the MAX doesn’t look good. That’s what happens, maybe, when you’ve taken what was originally conceived as a short-haul regional plane and stretched and tweaked and pushed the thing into roles it was never envisioned for. Throw in the engine’s awkward forward mounting position, and the result is a sort of Frankenplane.

        • Right Mell (ref, see the now totally discredited Bill Cosby)

          Sans AF447 when was the last time a commercial aircraft stalled? (not part of an out of control disorientation issue)

          All you got to do is turn the damned thing off.

          • @TransWorld

            Right Mell (ref, see the now totally discredited Bill Cosby)


            Sans AF447 when was the last time a commercial aircraft stalled? (not part of an out of control disorientation issue)

            What’s AF447 got to do with this?

            However, Airbus aircraft have a full Fly-By-Wire (FBW) flight control system and triple redundancy. Triple-redundant systems have four independent members, so if one fails, a two-to-one vote of the remaining three is still possible.

            One system = No redundancy.
            Two systems = Simple redundancy.
            Three systems = Double redundancy.
            Four systems = Triple redundancy.

            If you lose two systems of the same kind, the aircraft control system goes from Normal Law into a degraded flight control law — Alternate Law or Direct law.

            The problem on AF447 was that the Pilot Flying (PF) had insufficient knowledge and experience of the flight control modes. It’s very likely he’d never operated an Airbus in Alternate Law — a degraded flight control mode where the PF can stall the aircraft.

            In contrast to the triple redundant Airbus FBW design, however, the Boeing designed MCAS on the MAX apparently relies on two sensors only — if one is faulty, all hell might break loose.

            All you got to do is turn the damned thing off.

            The MAX is not certified to fly without MCAS.

            Apparently, Boeing figured out during flight testing that the MAX is not safe to fly without the addition of a MCAS-type software system.

            How then would the disabling of the MCAS system solve the problem?

          • @OV-099

            Everyone likes to pull up the “insufficient training” card, but pertaining to the MAX, the funny thing is that if there’s anyone who’s squarely responsible for insufficient training, it is Boeing/FAA who have decided that you need no more than a 30 minute iPad course and some NG sim training to get into the MAX when, in fact, there are some serious differences that pilots need to be trained to handle like the MCAS-off scenario you mention. And They didn’t require the pilots to know this. Hilarious.

          • “The MAX is not certified to fly without MCAS.”

            Yep, its going to fall out of the air if you turn it off. Of course it can crash if you leave it on. hmmm

            Are you kidding me?

            They deemed it an issue and not a critical one at all, the FAA made the call something needed to be done.

            Give me a break. If that is the best logic in the world we are truly in trouble (ad hominum?)

    • I’m wondering how on earth Boeing can get out if it does prove to be an MCAS problem.
      It would be a big problem for South West and Ryanair too.

      • It appears as if they can’t get out of this one easily. If MCAS is a requirement to ensure safe operation of the aircraft, disabling the MCAS system would IMJ require a comprehensive and costly redesign of the MAX.

        • Having only one type of combat aircraft saves a lot of money, but it’s risky because your enermy might know how to handle it. I have often wondered about the wisdom of vast numbers of single aisle aircraft built to only 2 designs and even more so the proportion of them with one engine type.Some airlines need to consider this as well.Replacing them is hazardous, multi stage like Airbus with the A220 is much safer.I have always had the suspicion that NMA is in fact NSA in disguise.

        • Back to, MCAS is a response to an issue of unknown level but not likely crisis degree.

          Turn it off

          Make the alerts standard

          Make it cross connected to both AOA and other inputs.

          All of the above

      • Addendum

        With the MAX it appears as if Boeing went one step too far in order to correct for airframe design deficiencies with the MCAS — seemingly believing that software is sufficient in counteracting the recognized hardware deficiencies and shortcomings in the aerodynamic characteristics of the aircraft.

        • Wow:

          Boeing was fine with it.

          FAA was not.

          Boeing implemented a Fix the FAA approved.

          It sucks as a fix and the FAA and Boeing suck for how they went about it and allowed, but its not a critical item.

          Pull the power and you can fly it fine without it.

          You do what for run away trim?

          • something that comes up in intervals is not “run away trim”. ( as defined in the checklist )
            MCAS errors come up as in stealth mode.

            Leaving that out of training scope imho was a trap well placed. Overall the system appears thoughtlessly stuck on.
            compare to the ever present big pi*sy words from Randy Boeing how nobody can touch Boeings competence. nobody can catch up to them.

    • Hindsight is 20 / 20. When Bombardier built the CSeries and Airbus responded with the NEO, then Boeing instead of complaining should have thought seriously then about a NSA, IF, if this MCAS and moving the engines around is actually at the root of this. The generation earlier, they responded to the A320 by lengthening the -800.

    • Once can speculate that a bigger elevator and maybe a simple pitch fly by wire a la Saab 2000 would make the MCAS not needed. A new THSA (trimmable horizontal stabiliser actuator) with built in computer and databus to the avonics and gyros.
      It would interupt production and require a new limited certification run before the SB is out.
      It took some time after the older 737 hard over accidents USAir Flight 427, United Airlines Flight 585 to get revised boxes out.

      • And they did not ground the fleet, the implemented a pilot fix as an interim.

        In that case a bad idea.

        In this case the fix is easy, turn it off software wise.

        No more problem until we fine out eh what.

        Damned things flies fine without it and don’t stall

        Simple. If you do stall, push over like you would anyway.
        You don’t need automation for that. If you do you should not be flying.

        • I think it is the non-linear pitch at high alfa before stall that is the problem. That alfa-dot does not meet present certification requirements in a corner of the flight envelope. Hence the fix to satisfy the FAA. Still one wonder if the requirement can be changed and pilots trained to handle this situation as 99.997% of pilots would never encounter it in operations. Boeing seems to have done a software modification of the MCAS system soon to be released. We will see if this software is sufficient of if new hardware will be needed. The de Havilland Comet took a Queens flight and 3 hull losses before they were grounded.

        • Boeing also revised the system thru some SB’s that changed some boxes that are AD requirements.

  8. How long does it take to realize MCAS is on? With a stick shaker and faulty airspeed, if the crew is distracted by that for 30 seconds, that may be too long. Even with nothing going on, how would the crew know that MCAS is malfunctioning and to override it? The first several cycles, the crew would just assume the speed trim is running and doing it’s job. Too sneaky.

    • Ted: On and active are two different things

      Unfortunately what can activate it is a fable input, no stall but being told its stalled.

      The fake out is you pull back on the column and it stops. Then it kicks in (7 seconds ) again.

      Boeing contend runaway trim procedure stops it, true, what they are lying about is the symptoms of runaway trim are not the same as MCAS actions.

      • Interesting that there are two pitch control systems, the tailplane and the elevators, and their interconnectedness shutoffs and logic. I have a switch for my car window that operates the motor up and down, but I take it a 737 there is no switch for the pilot to move the tailplane with the motor. The motor is only controlled by a computer for speed trim, mach trim, and MCAS, correct?
        I wonder why they didn’t hook up MCAS to the elevators instead of the tailplane? The tailplane looks to be the biggest movable control surface on an aircraft. Pretty important that the aircraft tells the pilots what it is doing with that surface and the pilots have motor reverse control authority, not just motor shut off.

        • No, you need to sort out the verbiage and its exact.

          Trim on the wheel is electric and runs the motors that move the stabilizer (stab). The various items Bjorn has listed affect it speed of how fast for various flight conditions. MCAS runs those motors. The wheel adjust the stab via a mechanical system. If the motors are on you will see the wheel spin.

          Turn motors off and you adjust the stab with the wheel.

          The yoke controls the elevator for miner flight changes by the pilot.

          Trim does a gross adjustment via the stab and you fine tune it with the elevators

  9. As noted previous, other entities can and are acting.

    Good on them.

    If its not the same, then we need to have an idea what it is before the MAX flies.

    If it is, then Boeing and the FAA need to get their butts in gear and provide the fix.

  10. It would be interesting to know how often this MCAS system has deployed itself automatically on other MAX’s since they have entered service.
    Writers here comment on the hugely ‘forward’ position of these new engines.Perhaps the aircraft is boardering on a ‘naturally unstable’ condition in certain ( full) load/power (T/O?) conditions?
    Yes fighter aircaft are naturally unstable but commercial aircraft should ( I imagine) be passively stable.Is it ?(under these conditions)

    • Or how many times has the autotrim system on the 737NG gone into a runaway condition where the tailplane has deployed to it’s full throw in either direction pointing the aircraft hard nose up or hard nose down? Maybe it is not recoverable in the NG either, but maybe it just never happened that the runaway trim condition has ever put the tailplane in an extreme angle until now.

      If it is easy to recover extreme tailplane runaway, where are the similar examples from the NG?

    • Phil: You really need to get serious or learn more.

      The engine are not hugely forward. They are more forward.

      The pitch up is not sure death, its just a reaction that if the pilot is doing his job, will never happen or is in the act of correcting already.

      Not is not on the edge of stability , those test ARE RUN FULL LOAD.

      Yes at times we get stupid decisions. Those are on the margins. The FAA does not certify an aircraft per your statement.

      Every other regulatory agency in the world reviews those and approves them or not.

      Brazil approved its cert but they also insisted the MCAS be taught as an added system.

      Don’t make this worse than it is, while its bad enough its stupid bad and does not have to be the world is ending bad.

      • @TW

        They may be extreme but that is what certification is about. The CG moment is sufficiently far forward to warrant concern over pitch control. I seem to remember it is not just the weight but the position of the engines forward and high which also has an aerodynamic or lift effect. So they have a pitch and yaw concern that the MCAS is supposed to mask.

        So there are all manner of issues to manage on what is a control system of 50s and 60s vintage. So they added a few safety systems to keep the gremlins at bay. To me this is a shambolic penny pinching approach which is not worthy of Boeing.

        Does anyone know the last big commercial airliner without FBW? B748 maybe? Before that?

        • Sowerbob: Keep in mind that Boeing did not feel it was an issue.

          Also, this is at the extreme edge of the flight envelope not anywhere near a normal envelope area of ops.

          Ok, take that with a gram of kerosene of course, but they are not completely stupid (I know this makes it hard to make the case but read Scotts house building adventures)

          The FAA feels its enough of a pitch up to be of concern and wants a correction. So, not a huge deal, FAA wins as its regulatory and Boeing comes up with a fix.

          Implementation of it is beyond stupid, the roll out (or non advising) is nuts, and the rest follow (no awareness its there, no alerts as those are optional and mean you have to tell people ad nausea)

          MCAS does not mask it, it takes action to stop it (so far as we know for the worse)

          Worthy of Boeing? Remember Lauda Air 767 crash and the 737 Rudder? Its right in Boeing wheel house.

          And all that stuff is still there in an A320, its just all automated and covered up. All this cute smooth etc has its costs.

          All aircraft can be crashed. System issues for the most part can be handled.

          You do need to know about them and train on them.

          In this case Boeing problem is they did not tell anyone and we don’t know yet what Ethiopian did about it (train on it, pilots aware etc) .

          SW, United etc all alerted pilots, did training and some are now (maybe all) the alert system for the AOA mandatory (I bet that its not an option for them now, ie you guys screwed up, you put it in at no cost)

          Its not a hard one to fix, it should have been fixed with a mod to make dual AOA mandatory (maybe GPW and not let it activate at anything but low altitudes where its an issue)

          What I don’t fathom is why they were allowed this aproach. You already have stick shaker and warning (one AOA buggered) and the pilot is going to push over anyway.

          If not does anyone think driving the nose down is going to help?

          Maybe all this stuff should be cross checked that you are on approach to a runway so you can just push the nose over.

          Where does it end?

          I apologize if I am off the edge but the stupidity of all this is just overwhelming. Lets take a miner problems and go kill people with the fix.

          Are they freaking out of their minds?

          • Interesting take that MCAS is a retrofit mandated by the FAA. Not saying you are wrong at all TW simply that I have no knowledge either way.

            If they had gone FBW like any other vaguely new (post 1995ish) aircraft then they would not have had the issue of a mechanical aircraft with support systems. Patching up such old tech is a recipe for problems

          • The trail of what happened is reported (I think Seattle times but don’t have the reference)

            Read the Air Current blow, he reports it as a slight issue.

            While overall I agree back fitting stuff to old systems is not a good way to go.

            You have missed Bjorns comments on how many levels of tuning are in that system already and the MCAS was a simple add on to that (as bad as it is, its not using anything new, its using existing that other software uses to tune control response to the flight conditions of cruise, decent, landing, take off)

            What do you think Airbus does? Same thing except the mechanical linkages with the trim wheel are not there.

            It uses the same motor setup as the Boeing does.

            What the emergency backup on it is I don’t know.

            There will be some way to deal with it.

            Nothing new in Boeing Max other than some code.

          • Also, this is at the extreme edge of the flight envelope not anywhere near a normal envelope area of ops.

            uninformed Tribal thinking.
            Flaps retracted and MCAS is in the loop.
            Feed it wrong information and things go pear shaped. No idea what other traps have been laid.

            Lets see what they find out for the ET flight.

      • Well you have been a busy boy on this thread!
        No I am not a commercial pilot or an aero engineer.I do have a PPL and qualified for sailplanes,handgliders. ( even paragliders) but clearly not enough!
        I stated ‘ others’ had stated ,regarding the revised engine positioning but if you prefer ‘more’ ( than previous) I will accept that.
        My point was that it would be interesting to know how often the computers on MAX’s have felt it necessary to engage the MCAS over ride system.
        If it’s just twice and both created a fatal accident then there is an immediate problem.If it’s lots of times ,then why? It would ( if true) might suggest that ( in climb from T/O in certain conditions)the aircraft has a narrow margin of passive safety.
        Both these suggestions might of course be wrong,but it appears that Boeing have already been asked to rewrite the software – why?
        With so much uncertainty I am personally surprised that a grounding notice has not been posted by the FAA.
        They now have both flight recorders of this crash and one from the previous.There should already be enough information available to make an informed decision.Lives are paramount.The long term reputation of the FAA is also critical if people are not to loose confidence in air travel.Its a wide responsibility.

  11. To be cynical. Looking at the nationalities of the victims of both crashes, no US citizen was impacted, so it is unlikely that the FAA or Boeing will react.

    • That is not cynical, its foolish.

      The FAA or Boeing wound not act if it was 100% US citizens if they could help it.

      The 787 should have been grounded on the first battery failure.

      They simply are doing what they always have done and they only will act when forced to by outside forces (in this case world wide grounding that is developing)

      Neither one is the least bit discriminant, they don’t care about anyone until it impact them.

  12. The Max 8 MCAS is not supposed to be able to activate if flaps are deployed. Of course it is only speculation at this point if MCAS is involved here, but would Flaps 1 (or 2 or 5) with max KIAS of 250 knots provide flight envelope protection during a more extended climb?
    It seems like as a fuel savings, airlines are retracting flaps and accelerating sooner in the climb profile than what I remember years ago.
    Of course if there is a massive failure of MCAS, being at higher altitude won’t save a flight. But if an aircraft has at least 10 or 15,000 feet of AGL margin before MCAS can possibly activate, there is more time/altitude to use the manual trim wheel to override a wonky MCAS.

    • Wasn’t speed sinficant higher, remember seeing that is ATC data.

      • Keep in mind MCAS at altitude where you have time is the same as runaway trim, you just pull the power.

        Its only not being aware what its doing that is the issue and its not the same as the -800 and prior.

    • Don’t the flaps start retracting automatically (in steps though) at speeds over 200 knots?

  13. Is it possible to retrofit a more comprehensive FBW system into the MAX? It looks like going ‘old skool’ has suddenly become less fashionable. I remember the discussion about the MAX during gestation when a number of clear issues were highlighted in the development relating to weight and size of the new engines amongst other matters. Further Boeing turned around the design at breakneck speed in response to the neo for which they were commended at the time. Perhaps this is an iteration too far or the development process was too time constrained to truly understand the implications of what they had done.

    • The cost would be insane. Yes you could do it, you are better off with an all new aircraft program.

      And automation is not always the answer (see the AS dumping on A447 when the pilots did not know how to fly)

      Prior Airbus has its share of automation A320 crashes.

      • I think you should stop here producing false witness stuff.
        Never confess up to errors made.

    • I suspect that would be a non-starter. It would involve so much work that you might as well just start on the NSA then. Which is what they probably should have done in the first place. If, by the end of today, they haven’t shelved their silly plans for the NMA (No Market Available?) and devoted their resources to thinking about NSA, then the board should fire Muilenburg. That’s not to say that they will immediately proceed to launch NSA, but that they should be prepared to do so in case there is no easy fix for the MAX. It’s just smart strategy.

  14. “Tamirat Abera, 25, was walking past the field at the time. He said the plane turned sharply, trailing white smoke and items like clothes and papers, then crashed about 300 meters away. ”

    If that eyewitness is right, sounds like there was a hole in the baggage or passenger compartment.

    • Yes, I can see why the eyewitness reports are being criticised, especially when the witness seems to pick out distinct items like clothes.

      However visuals of smoke trails and a fire (presuming the fire was that large it could be seen from the ground), should be taken seriously.

      • No eyewitness should be considered anecdotal unless there is a smoking gun involved.

        So far there is not.

        I personally know of two people that saw the same murder, one swore the guy did not do it and the other did.

        The guy who said it did not happen testified for the defense.

        All the physical evidence (a lot) was 100% solid that he did kill the guy.

        The wrong witness is a pillar of the community and a professional engineer. If someone (who has no connection to the murder other than out front of their townhouse) can screw it up, then anyone can and they do including inventing things and they believe it no matter what the evidence says.

  15. Given the discussion around the Lionair accident it seems likely that this crew were aware of MACS and will have had the proceedure to disable it in the front of their minds. On poster is saying MACS isn’t enabled at this point in the flight anyway. Lionair changed the AoA sensor before the final flight and tested the new sensor as per proceedure. Is there something in the flight management software, a bug, which allows the system to keep trying to override the pilots with MACS apparently turned off? Could it be that neither of these accidents is related to the AoA sensor? Just a few lines of code could be behind both these tradgedies.

    • Martin:

      You are twisting this up.

      You have not read Flight global which I present again on EA operation.

      So yes you can have that level of incompetents in an operation.

      We have not hear squat from EA about what they did about the MCAS have we?

      Lion did not FIX the problem. Where that bad data came from we don’t know. And it does not matter.

      Stop/purge disable MCAS software and its not an issue.

      Train pilots and have the option alert thingies installed and (supposedly) its not an issue.

      Cross link to two AOA sensors and hopefully not an issue.

    • But don’t worry, they also expect to mandate design changes by April (per the article). Yup, definitely nothing to see here, just move along…

    • It is the FAA man! If they say so that is all that matters.
      Until they have to turn about face.

      Though it looks like Boeing was able to foist off the effects from design deficiencies onto pilot error in a row of cases.
      Horray to fast talking lawyers 🙂

  16. It worth re-reading this to keep the players in mind.

    Trim affects the stabilize (pilot induced) the trim wheel does and the automation does.

    Trim wheel will spin if the auto system is driving the stabilizer one way or the other. Pull the stab and the trim wheel is then the only driver.

    Yoke affects the elevator which is much smaller and less influence.

  17. FAA wants you to play a game of MAX roulette until the cause is identified. Brilliant. They see no such thing as better safe than sorry even though this aircraft has a known unresolved issue that arose in a similar phase of the flight.

    • That is the FAA MO and default.

      You will notice Scott also went there in the first post.

      Nothing against Scott at all, but he is not an engineer and the logic he works within is not the same as being better safe than sorry.

      Yes it may be something else entirely, but if its not then it needs to be addressed.

      You should balance your available facts (not a lot) vs the consequences and then come down on the safe side.

      Its the sort of thinking that killed two shuttles

      You launch when its too cold and get away with it then you launch colder still and people die and a shuttle is gone.

      You know you have debris off the tank and you think, well noting happens so nothing will, but you don’t analysis it ans run the calcs that show how much inertia the foam had and what it would do if it did hit the tiles.

      The term is normalizing deviation.

      This case clearly is not weather, it has no hallmarks of a terrorist (we need to return) no missile was fired (and in Africa that not only could happen it has)

      Ergo, this is not normal and stop the show until we get some data one way or the other, then decide. Black boxes in a few days.

      737 Rudder issue was ignored and two aircraft were lost.

      Laud Air lost a 767 and it was the pilots fault until it was not and lucky no other 767 was lost in that long period.

  18. This is also good. It should be kept in mind that while the MCAS is pushing the nose down, the stall alarm is on and stick shaker is going.

    On the other hand your instrument scan tells you that you are not nose up, your Vertical Spreed Display (VSI) is not changing (going down fast per a stall) and your altimeter (slower and a bit less indicative than the VSI) is not winding down.

    You have to figure out this fast when a simple display that says AOA is wacky would be what you want.

  19. The problem is that one happend in Indonesia, the other in Ethiopia.
    If it would be US or EU airline it would have been very different reaction……

  20. Apparently there are a number of posters here (and on other aviation boards) that have access to the final root cause report for the Lion Air incident and to at least a preliminary report for the Ethiopian incident as well (quick work that). It would help if those persons could post links to these reports so that we can all be working from the same set of information in this discussion. Thanks!

    • Final report will be some time, but the preliminary one released has 90% of the relevant information
      ‘Indonesian investigators released a preliminary crash report today (Nov. 28) that described a battle between the pilots of Lion Air flight JT610 and an automated anti-stall system on the Boeing 737 Max 8 aircraft that continually forced the plane downward in reaction to incorrect flight data.’

      yes the previous malfunctions are relevant, yes the perfect world waits for the exhaustive investigation( While Boeing starts from scratch to redo the entire MCAS system during the investigation anyway)

      Yes in the end the FAA and Boeing will call it a durability software upgrade unconnected to the crashes and carry on as though nothing happened.

      • Duke: They will carry on, more ignore what they did that pretend it did not happen.

        It is an ugly part of the US system.

  21. And now for another perspective on this situation. Certainly not the only other perspective, but another perspective that like ALL other reasonable perspectives, a sound mind should be open to until facts demonstrate otherwise. With all the freshly minted A320s and 737s being cranked out, is there always a seasoned or freshly minted set of QUALIFIED pilots for each plane when it is in service? Both airplane production lines are pumping out planes at record and increasing rates. Have the increases in numbers of qualified pilots to operate them been able to keep up? Same question can be asked about maintenance personnel.

    • A good question, but not relevant to the incidents under discussion. Unless you think that somehow all the incompetent maintenance and flight crew are being exclusively assigned to the MAX, even though it comprises a mere 2% of the current narrow body fleet.

      • Mike: I disagree with you and it is a good questions.

        Its been clear for some time there are a lot of unqualified pilots out there. Just look at the record of self induced crashes or contributed to (virtually all were of that sort)

        Indonesia clearly had issues as they had 3 flight with a faulty aircraft both pilot and maint never got it right.

        Don’t get me wrong, something like MCAS should not be inflicted on an aircraft the way it was. Or the infamous FLCH Trap on Boeing auto throttle (NTSB has told them they need to change that and ignored by B and FAA)

        That said, the last Indonesian flight they pulled up the flaps and it went off the rails. Down again and it stopped.

        Me? Ok, put the flaps back down and return to the airport. I don’t care what the cause is, I want it stopped and that stopped it.

        And what process and procedures are there for that AOA issue ? Why was it not fixed? What did they find? It clearly was 20 deg off on rotate ?

        That does not cover the Speeds issue that is also part of this (or was present at least on the pilots side) That is also a maint issue.

        So yes, I think we have a lot of poor pilots and a lot of poor maintenance and its something very relevant and possibly key to this one as well.

        If this is true MCAS induced, 2 crews and maint operation did not deal with it right and 2 pilots did not deal with it at all.

        I believe in both the two non crash flight it should have turned back, reported and test flown per regs.

  22. Could it be that the MCAS misbehaved so the experienced pilot turned it off, but then the plane actually stalled?

    • Highly unlikely.

      Don’t conflate stall with MCAS,

      MCAS is supposed to engage in a stall not prior.

      How much that is needed I seriously doubt its that important as the pilot would be taking preventative action prior to that.

      Stick shaker and alerts before. Its an assist if anything (or supposed to be)

      Better question is why we still use Pitot for speed and a single AOA input to get a system screaming at you.

  23. Plane crashes, Boeing starts designing new software, another plane crashes despite the knowledge of what happened to the first one but it’s perfectly OK to carry on flying for another month without the new software. I can’t make sense of the FAAs position.We don’t even know for sure that the software patch will cure the problem,or do we?

  24. Singapore has barred max from its airspace. I think they are well respected and this will probably force a grounding.

  25. Singapore has now banned 737MAX from its airspace.

    The FAA has now clearly lost the confidence of some major governments. Those governments still permitting MAX operations are probably going to start feeling the heat for doing so from their politicians and populations. Plus they have to consider the possibility that another crash will occur, but in their territory; that’d be hard to explain, given the groundings elsewhere. Do they want to take that chance?

    Soon the MAX could be a US-only aircraft.

    It’s doubtful that the FAA’s credibility around the world can be easily restored. Their initial and enduring approval of MCAS is hard to explain, even if this latest tragedy has nothing to do with MCAS. If this was MCAS again, well that’s effectively the end of the FAA’s role as one of the world’s trusted type approval bodies.

    Governments might start questioning the safety of other type approvals issued by the FAA. How many other Boeings might that ground? A lot of these are flying literally because, “The Americans said it was safe”.

    There’s not even a need for such extended concerns to be realistic – it’s given countries looking for a geopolitical opportunity to sting the USA a cast iron excuse for slugging it to Boeing.

    Singapore is interesting because it’s not a country one would ever identify as wishing to annoy the USA. Far from it, in fact. Nor could it be labelled as anything but competent.

    • Mathew: Life will go on, its not the end of the world or the FAA

      Don’t ramp this up to the end of the world (form some it was but bureaucracies persevere)

      If we are lucky we will get to break the regulator part of FAA away from the cheerleader role for aviation.

  26. “[Update, March 12, 9:00am] The civil aviation authorities of the United Kingdom, Australia, Singapore, and Malaysia have now also grounded 737 MAX aircraft flown by their airlines. The additional groundings account for about 40 percent of all 737 MAX aircraft in service. The United States’ Federal Aviation Administration has not yet taken any action, citing the absence of conclusive data on the crash’s cause. An investigation is still underway.”


  27. Just remember these 2 crashes happened in clear daylight conditions. In poor visibility or night, the pilots won’t have a prayer. GROUND NOW!!

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