Pontifications: Boeing can’t catch a break

By Scott Hamilton


Some may argue it doesn’t deserve one, given what’s come out about the 737 MAX development. And the sloppy production of the 787 at the Charleston (SC) plant. And the FOD issues with the KC-46A at the Everett (WA) plant.

To be sure, Boeing has gotten a lot of bad press it’s deserved. But last week, two pieces of news had connections to the MAX that were (1) overwrought and (2) unwarranted.

Flyadeal “cancels” “order”

Flyadeal, a low cost airline in the Middle East, last week “canceled” an “order” for Boeing 737 MAXes. And the media went wild.

This is one of the most over-reported and over-rated stories of the year concerning MAX.

The “order” wasn’t even an order. It was a “commitment” (ie, a letter of intent or memorandum of understanding) made in December 2018. It never was firmed up. So Boeing didn’t lose an “order. Until a deal is a deal, it’s not a deal. (Note: IAG.)

Second, Flyadeal already operates the A320. It made more sense to stick with the neo than to switch to the MAX. Third, Flyadeal gets the neo sooner than the MAX.

OK, fine, Airbus got Flyadeal. Boeing got IAG (200 airplanes). These things happen.

It’s worth noting that the IAG deal is not yet a firm order. Airbus vowed to submit a bid. Unless or until the MAX LOI is firmed up, it’s not an order, either.

LionAir, which was very vocal about canceling its MAX order, hasn’t done so.

Garuada swapped MAX 8s and MAX 10s and 787s. This was a smoke-and-mirrors things.

Now, if United, Southwest or Alaska placed a big order for the Airbus, then Boeing would have something to worry about. If any of these canceled MAX orders, then Boeing would have something to worry about.

(NB: Alaska continues to evaluate A321neo and likes the airplane. If it were to order this airplane instead of the A320neos Virgin America had on order, I wouldn’t read anything about it into the MAX crisis. The A321neo is a far superior airplane to the MAX 10 and it’s also better than the MAX 9 for revenue potential, range and field performance capabilities. United Airlines is evaluating the A321XLR, and should it order, this, too, is unrelated to MAX crisis.)

I’m unconcerned about Flyadeal.

China and EASA

China’s agreement between CAAC and Europe’s EASA was touted by someone who really doesn’t know much about these things as a slap at the FAA, again connected to the MAX crisis.


China wants reciprocal certification for COMAC’s C919. It has been slow in certifying individual Airbus airplanes for delivery into China. It struck a reciprocal agreement with the FAA several years ago. The agreement, announced in May (coincidentally during the Airbus Innovation Days), was on its own agenda.

LNA wrote about this issue at the time, on May 23.

Here’s what we wrote then:

China certification

The proposed US/China Bilateral Safety Agreement (BASA), in which reciprocal aircraft certification is granted, is the model for a similar agreement with Europe’s EASA, which certifies Airbus aircraft.

[Airbus Chief Commercial Officer Christian] Scherer said no similar BASA agreement has been reached with EASA and China. But he said Airbus should be able to apply for certification under BASA, because EASA and the FAA have reciprocal agreements.

“It should lead to the opening of new market opportunities,” Scherer said. “I’m thinking of the 220.”

Losing the lead

With undelivered MAXes piling up, now at the rate of about 42/mo (since the last NGs have rolled off the line), one media outlet wrote that Boeing will lose its position this year as the world’s biggest airplane maker.

This is stating the obvious, but to me it falls into the “so what?” category.

Wait till next year, when production rates return to normal and deliveries of the Undelivereds surge.

This year is an anomaly. Next year will be, too. Normalcy returns in 2021 (presumably).


130 Comments on “Pontifications: Boeing can’t catch a break

  1. Hi, agree the media was really been pumping up things in recent weeks. However Boeing wasn’t shy when Flyadeal selected efficient 737 MAX for future fleet and international expansion either.


    The press was all over the IAG deal too, making little difference between LOI, deal and orders.


    Everyone knows (the CEO said so) IAG has a problem with Airbus, AIG is not boosting the 737MAX.

    All said and done, I sense unrest with the airlines about the Airbus-Boeing balance. The business as usual / people forget / everything will be fine – lighting rods are melting.

    “OK, fine, Airbus got Flyadeal. Boeing got IAG (200 airplanes).”

    Did they? 😉

    We don’t follow many french, german and spanish news outlets and in general the press is supportive of Boeing success. LeehamNews IMO being one of the few calling a spade a spade.

    Weather warning: it’s very silent around the 777X. An entirely new aircraft, but certified using 77W grandfathering rights. Certifified by the same FAA and the same Boeing, using the same self certification processes, in the same time frame and a competive pressure situation just like the 737MAX. I wouldn’t assume all is just fine because Boeing and the FAA are quiet.

      • Yeap, 777x certification is the same kind of Pandora’s box like MAX.

        I hear W. Walsh complaining about Airbus this, Airbus that, but I can’t really find in this complaints much quality.

          • @Jno

            Couldn’t agree with you more and I seethe B77x as an amalgam of proven B77w, B787 and B777 systems and the only demonstrably new element being the wing in size and the folly bits.

          • So what from which year is a grandady.

            777x certification procedure is the same as MAX – “self certifying by Boeing” – same rotten apples :/

          • Whilst the 777 is a much newer basis, that doesn’t mean that the 777x development hasn’t shared some undesirable features with other recent Boeing developments.

            I don’t think that it’s the vintage of the base design that matters. What matters is the company / certification regime under which changes to established designs have been made. Both 777 and 737’s origins predate the current company management and their approach to certification. The problems that have afflicted Boeing aircraft are traceable to work done and decisions made in the past 20 years, not to the base designs. And the 777x is being developed under that very same regime.

            And there are publicly visible warning signs. For the 777x, there’s at least one former Boeing electrical engineer who was dismissed (so he’s claiming in the court case he’s brought against Boeing) for raising safety concerns, having been brought into the project only a month earlier from their space division. Reports on the court case have it that GE, the company that picked up the manufacturing work, had also reached conclusions similar to those of the sacked engineer. Or, something like that.

            You can also look at it this way. Going from divisional transfer to fired in 1 month? After years of service elsewhere in the company? Does that paint a picture of sweetness and harmony within the 777x project team? Or is it a deeply disfunctional environment in which an aircraft can be safely designed and developed? I don’t know for sure of course, but let’s say that the signs aren’t promising.

            This kind of dirty linen being washed in public ought to receive more attention from the regulators than I think it gets. Apart from anything else (like, is the design any good), an aircraft OEM has to be a fit and proper organisation to safely undertake the task. And it’s up to the regulators to assess that. We demand that airline operators have measures in place to ensure good cockpit relationship management. I don’t see why the aircraft OEM shouldn’t bear a similar burden of responsibility for its team.

        • Pablo,
          You are right, and also Walsh is playing the Sourpuss with Airbus due to its Brexit panorama, but he forgets, between how many UK employees(Airbus Wing Plants/ Rolls Royce, and Independent UK contractors have at stake). Has Walsh not gone through the Delay transition of the B 787’s for several years?

          • 777 is not in the same category as the 737. Its a modern aircraft not a legacy from the 50s.

            I bet they take a longer look at the folding wing system which I do not like aspects of (and I commented to the FAA on those)

            The FLCH should be addressed but I don’t think it will be.

          • @TransWorld

            For me doesn’t matter if 777 is the same “age category”, or any other category, like 737 or not. I have nothing against well thinked development, but I’m against screw ups. And 777x certification procedure, same as MAX one, is a clear danger in Boeing’s hands.

    • 777x is not an “entirely new aircraft” as you state above. I suspect Boeing and the FAA are also of similar thinking that they need to review the certification process for Max-like anomalies.

    • Here’s a different version
      The gist of it is
      “Personally I remain skeptical for now.

      With all due respect to Mr. Walsh, him saying that something isn’t about price isn’t especially believable. I have a lot of respect for the guy, and part of the reason he’s so successful is because he is always concerned about price. Always.”

      After all delivery delays are normally a combination of things…manufacturer, engine maker (at least the neo has a choice with that one) and even interiors have been problematic depending on the supplier , again chosen by the airline.

      • It’s spin I think. In effect Boeing is paying British Airways for its endorsement of the MAX in the form of steep discounts. Neither side has an interest in being open about this.

      • @Dukeofurl
        I see it similar. Not for everything it’s reasonable to blaim airframer, but it’s sells well to press.

        • When you think about the fuel oil prices back around 2013 when IAG place its ‘definite’ order for Neo jets that are being delivered now, that will show Airbus could ask for and get good prices due to the improved efficiency and reduced fuel cost.
          Now a lot of the fuel price pressure has disappeared the economic gains are less and the ‘asking price’ for a re-enginned single aisle fleet would be lower than 2013.
          Looks to me like IAG wants to try to renegotiate the pricing on its old A320neo order and get a killer deal from Boeing at the same time ( Included with Boeing taking over the IAG maintenance facilities)

          Airbus can be hard nosed about this too, as IAG will end up with far too many planes if the Boeing order is finalised. Sure they could quit the A320 neo fleet they are contractually bound to take, but it would cost them plenty either to walk away from current deliveries and later sell the neo fleet in 5 yrs when the Max get delivered. Good luck on getting a deal on todays low fuel price value for planes you bought at a time of high fuel prices. The fleet size means a leasor is about the only taker.

    • There is a shortage of GE LEAP 1A and PW1100G for the NEO causing airbuses delivery delays. I can’t imagine that the LEAP 1B for the MAX is any better supply than the LEAP 1A. LEAP engines intended for neo’s are assembled in France by SAFRAN and those for the MAX in the US by GE. As the hot section is the same I imagine the down turn of MAX production should at least help GE/SAFRAN catch up.

  2. Scott,
    are you certain that Boeing will recover all of their deliveries throughout next year? That seems like an awful lot to catch up on. Not to mention, we still do not know when the grounding will officially be lifted.

    I suspect that 2022 will be the next “normal” year.

    • @Aero: Until Sunday, after the post was written, I felt pretty good about the grounding likely being lifted around October. I felt it possible Boeing could clear the backlog by Dec. 2021, or maybe have a little spillover into 2022. (One analyst sees worst case scenario it taking 22 months to clear the backlog.) Then on Sunday the Wall Street Journal indicated things may not clear and gt back into the air until January. This, of course, slides everything to the right and adds 2-3 months more Undelivered airplanes. Then I talked with an ex-Boeing person who thinks it could be next March before Return to Service. He had no basis for this other than a gut feeling. FWIW.

      • So what upgrades and updates will the MAX need? New CPU, new software, additional AOA sensor, new wiring for the AOA sensor, new display,… a new speed trim system with servo supported trim wheel? A larger stabilizer and/or elevator?

        Maybe March is optimistic. And even if the MAX is re-certified by then, it will take a long time to implement all these changes to all finished planes (at the airlines, in the parking lots, in production,…) and reset the supply lines and production.

        And will Boeing’s cash suffice? Or will it all be done under chapter 11?

        • You miss the issues.

          Two AOA are on the aircraft, you just need to bring them both into the program area that makes the MCAS decisions.

          They landed on the moon with a computer that had less capability than my hand calculator does.

          You just need to manage the data. Update rates adjust and or how many decimals the data goes out to, whats the dead band? Do you need to know 100.1 knots or is 100.0/100.5 more than enough.

          Boeing is not going Chapter 11. You do know that the shares go to zero and all that stock buy back effort? Ain’t happening.

          • The issue with alterations to Flight Control System related computers is certifying. You have to certify the Application code, the compiler, the operating system, the CPU, the hardware. Change anything and it may effect the other. That means a bunch of check lists and tests that need to be recorded. Now poor old Boeing is going to have the finest experts and professionals, the kind that write text books, pouring over their procedures and methodologies. When you alter software you have to record a change notice, where is the document where that was recorded and the FMEA etc. These are also highly complicated systems with communication buses cross checking. Improving the efficiency of the code with better algorithms is probably ideal solution but if they can find a faster clocking CPU and/or fit in more memory it would also be great. I’m not sure where the bottleneck is, could be communication buses, but there is a lot of cross checking going on. (maybe the new redundant MCAS pushed it over the edge) The interesting thing is that the alpha sensors used on the B737MAX are a very old design also used on Hercules and have two pickups internally. What was Boeing doing with that?

          • No, you then have an all new aircraft.

            Aint’ happening.

          • Not really. A300 was essentially similar to it’s FBW derivative the A330.
            Airbus had it’s A320 to work from and Boeing has done the 777 and 787 and presumably will be well advanced on the NMA software.

          • The difference was that the A300 was a modern air-frame. Worth what they did in the A330 latter on though no payback on the low sales A300 series.

            737 is not only mechanical originally its structural limited.

            Update it will take no less than 3 years, recert and then replace it?

            Not happening.

          • A300 and its derivative A310 had 561 built, which was a good number for the time and from a ‘new airframer’.
            Compare to DC10 with 446 built inc KC10 , and later MD11 with 200 built.

      • The elephant in the room is the “excessive force needed to turn trim wheel” issue raised by EASA. That is the one that could really blow things up.

        Everything else, MCAS software, more reliable AOC indicators even HW upgrade on the FCC can be handled. But if an agency decides that 3 seconds of run-away trim could result in a situation where the force needed to turn the trim-wheel exceeds what the weakest pilot can apply then things will get very sticky for Boeing. It is not clear how they could address that.

        • This was NOT ORIGINALLY raised by EASA

          It is a factor listed in their concerns.

          In fact it was revealed by US people and has been on the radar since then.

          As bad it was found the Simulators had been kludged with and no longer reflected what the forces were.

          Also revealed by US investigators.

          And I have stated many times, its really the biggest critical issue remaining.

          And its a huge one. Basis of the logic is its a usable and reliable backup. Its currently not and I don’t know what you can do to correct that.

          • Both British Airways and Ryan Air employ female pilots who are unlikely to have the physical strength of there male colleagues. For successful re-certification surely they must use simulators that faithfully replicate the actual physical forces of the real MAX’s trim wheels in ALL situations and these have to be easily handled by every MAX pilot – even the female ones.
            Until that has been demonstrated the MAX should never have been certified in the first place.

        • And from what I’ve read today, the Max will be rebranded which I thought would happen. key in short attention span from the vox populi. However, the various foreign airworthiness certifyers just may have a thing or two to say about this albatrosses airworthiness.

          • More lipstick on that old pig? I can’t see that to work for airlines or any authority. Maybe not even the public.

          • I wish you would not fall to calling stupid names.

            The 737 is old but its not a “pig”.

            The fact its been horribly served by current management does not make it one.

            I will be first in line to have said that the NG should not have happened, and at the very least it should have been the last.

            The Model T was an outstanding vehicle in its day, its day got superseded and it was replaced by the Model A.

            It was not a pig, it was just original auto tech and tech moves on and when it does its time to retire the old model and bring in a new one and honor what the old model was, a pioneer.

          • TransWorld, I didn’t mean to hurt your feelings towards the 737 and I agree with you that the Classic was a wonderful plane at its time. Putting “lipstick on a pig” is a rhetorical expression that I applied here without any bad intentions:


            Besides, I also didn’t mean to insult any old pigs by comparing them to the MAX.

          • BernieNZ,
            Sexism isn’t necessary. I’ve seen some skinny little male pilots out there with shoestrings for arms. If there’s an issue of minimum strength necessary to fly the plane safely, then they can make that requirement without saying anything about gender. Still, I truly doubt that many pilots would have had the brawn the brawn to counteract the forces on those downed airplanes.

      • Scott, I disagree a bit in timeframes.
        Every month the Max is grounded adds 42 Max that have to be delivered.
        Airlines and Boeing can’t just hand them over all together when Boeing ramps up to 55 B737max again.
        Airlines will tend to not take additional planes in Q4 and Q1 due to low demand.
        It might take way longer than we expect, especially if oil stays cheap.
        Even if Boeing get’s the Max back in the air End of 2019, we still will see effects in 2021 in form of additional planes beeing delivered

      • Trump bases a lot of his beliefs on his gut also. Facts please.

  3. Imho Flydeal canceled deal is a lost real deal for Boeing. Isn’t commitments normally converting to orders?

    And its always a slap in cheek for Boeing’s MAX publicity.

  4. As things are developing, it would appear that there is a risk of the 737 MAX not being re-certificated until the 2nd half of 2020, or later.

    One should also keep in mind that deliveries of new aircraft is an elaborate process. 737 MAX customers can’t significantly increase deliveries in order just to help out an ever-more-desperate Boeing. They have a finite number of aircraft delivery pilots and a finite number of personnel that are qualified to handle all of the inspections, paperwork (etc.) that are involved. Also, acceptance of new aircraft is typically coordinated with a carefully structured phase-out planning of older aircraft. Furthermore, deliveries represent a challenge for airlines and/or lessors who must be ready for selection, contracting, acceptance and delivery of many airplanes in processes representing a significant economic impact into their accounts.

  5. To me this article appears to be a little excessive.

    I note, most of the hyperbole, as described in this article, as come from the US media. As a Brit, it’s something that causes me to do a lot of yawning. In other words, I’m used to hyperbole from the US media.

    I also note, elsewhere on this site, other’s have addressed Loren Thomson. Does anybody take him seriously? He is known to be a paid mouthpiece of Boeing. Anybody remember his defence of Boeing with regard to Boeing’s action against Bombardier and the then C Series. That worked. The A220 is becoming an awesome success.

    This comes to regulation:

    We keep being told by the US media, including LNA, that the FAA will go it alone with the 737 MAX. So what? Who cares? Big deal?

    Given the behaviour of the FAA it is right and proper that other regulators do their own thing!

    With regard to other regulators. Will other regulators return the 737 MAX to service with just software changes to MCAS? We are seeing the first glimpse that the answer will be no. Perhaps, as some have suggested, that’s the reason for the Loron Thomson article.

    This comes to the narrowbody market:

    Airlines don’t have any choice. The choice is coming, but it will take time. Specifically, 2024 onwards. So airlines do have to stick with Boeing and pray their own regulator returns the 737 MAX to service.

    With regard to the Saudi deal, The Saudi deal is more about widebodies than narrowbodies. Airbus want Saudi’s widebody order. So Airbus have done their best to accommodate them.

    With regard to IAG, Willie Walsh is having a strop at Airbus in the fashion of Tim Clarke having a strop at Airbus. Market conditions are forcing Tim Clarke to come to his senses. I’m sure the same will happen with Willie Walsh.

    Boeing are getting what they deserve with regard to the 737 MAX for even now Boeing are trying to brazen it out.

    • If you follow this, the FAA is working hand in glove with the other regulators in dealing with getting the MAX back into the air (or not)

      That could change but I don’t think so. The FAA has huge egg on its face and does not want a AHJ blow up on top of it.

  6. Yes. It’s all very well to flick off the Flyadeal non order, but if the boot was on the other foot and the same non deal was announced at Paris , Boeing would be happy to have the headlines.
    I wonder if this part of the new PR strategy from Tukwila, as seen in the Loren Thompson fact free farrago, poor little Betty Boeing so hard done by……

  7. Boeing, will still be Boeing and its order book isn’t going anywhere, anytime soon, however…constant negative press and a reputation for trying to strong arm the flying public (legal machinations and insurance payouts) give the impression that Boeing is only interested in making money for its shareholders and by dint of this bonuses for its executive management team.

    Bullying the State of Washington into giving it huge subsidies; bullying its unionised workforce into accepting further cuts in their packages and benefits; outsourcing of key work to low cost subcontractors; threatening airlines with sanctions and generally using financial doping to boost their financials all speaks to a culture that is self-serving and morally suspect.

    Boeing is unlikely, IMO, to quickly recover from the perceived culture at play at the heart of the company, however technically solid (or not as the case may be) its products are…BUT, if it offers huge discounts on its products it may well serve to stem the tide…but at what future cost?

    Airbus has had its fair share of problems yet these are now playing out and heading to the last act – technical , managerial and corruption – so is able to look to the future with greater equanimity than Boeing.

    Airbus’ new sales guy seems to have his feet firmly under his desk and I believe will really start to focus on the twin aisle campaigns going forward. The XLR and 30Neo being great aircraft available at relative bargain rates…win these deals and these are generally financially positive, lose these deals and Boeing is forced to take a financial hit on the pricing – particularly so given the 87 will likely never make a real world profit!

    Interesting times ahead…

  8. I do think Boeing will lose a lot of 737 MAX orders. As I said previously there is no choice today but choice is coming. The reciprocal agreement between the EU and China will open up markets for COMAC. Within China we will see 737s swapped out for C919s, with the A321 being safe for now.

    With regard to Airbus, for me the next big move in the short haul is the A220-500. Not possible now because of production problems. As it stands, Airbus are having difficulty producing 50/year. When that goes to 100/year they will launch the A220-500. My expectation, EIS ~2024-2025, by which time Airbus will be able to produce ~200-300/year.

    Then add 800-900/year A320/A321s, the majority A321. That’s 1000+/year narrowbodies for short haul/medium haul.

    Put it all together, Boeing are in for a ruff time even if the 737 MAX is given the all clear. It won’t get better with the launch of the NMA.

    But as I said they do fully deserve the wack that they are getting. Their behaviour with regard to the 737 MAX is terrible.

      • Yeah, seen it. Boeing’s view that the regulators outside of America will bow to them isn’t working. I think regulators outside of America are beginning to set out conditions that cannot be fixed by software alone.

        Boeing may rue the day that they decided to avoid an aerodynamic fix to prevent pitch instability!

      • The article assumes that Boeing will be just downloading a software patch to fix the 737-MAX issues. The “software defined” plane. If they need any hardware fixes, I assume they will set up some satellite retrofit bases, like they did for the 787 battery problem, using San Antonio etc. That will impact the return to service timeline. I’m interested to see how Boeing handles the manual trim wheel force issue. And if they rewire the stab cutout switches back to the previous configuration.

        • I may be corrected, but I think LNA have always taken the view that software alone will fix the 737 MAX.

          I’ve always taken the opposite view. Software doesn’t change the laws of physics.

          I remember the manual for my new car. It was clear, my new car was still subject to the laws of physics despite all of the bells and whistles.

          So the car manufacturer who provided my new car told the truth. No blowing smoke.

          Software alone won’t fix the 737 MAX

  9. The real impact of the Boeing crisis remains to be seen. One can wonder if large airlines that have a long habit of purchasing planes exclusively from Boeing or Airbus or stick to one model won’t have second thoughts.
    It will be interesting to see if, in the future, airlines like Southwest, Ryanair or Air Asia will stick to one airplane type or will diversify their fleet.
    I guess that this is the key lesson managers will have learnt from the current crisis.

    • Especially 1_type_of_aircraft_carriers shall be deeply concerned about where Boeing is going. If this had happen in 2020 for Southwest or Ryanair it would be a clear bankruptcy.

  10. Did thus author say “oh, it’s just a commitment, Boeing orderbook SUCKS” when a large fraction of the ‘orders’ were merely commitments?

    Methinks the lady doth protest too much.

  11. Nonetheless :

    Boeing loses a further potential order.
    Just like the 7810 order presented with much fanfare
    and extended swagger some time ago. … Then … nothing.

    Lets see how the BA “order” fares.

  12. 1. The media is NOT publicizing the incompetence of the flight crews of either of the 737Max crashes. I suspect Boeing is unwilling to place the blame on those pilots for fear of losing that country’s business, finding it cheaper to just pay-off and move on. Boeing CEO McAllister has not had the courtesy to respond to my letter(s) to him on this subject asking to him cease falling on his sword.
    The trim system on the 737Max is no newer or much different than the 1958 Douglas DC8 (PTC), 1966 Douglas DC9 (MTC) or EVERY Airbus ever produced (called Alpha Floor). What’s so hard to understand? Turn off the system and hand fly the airplane is NOT rocket science for a competent pilot.
    2. The KC46 tanker REMAINS an unending problem for the USAF. The program needs to be scrapped. The KC46 does not and CANNOT carry out the mission that the KC135 and KC10 already do. If a KC46 loses one of its two engines, it MUST immediately descend and slow down, thus negating the high altitude need for refueling for certain jets. It also likely abandons the mission and goes to the nearest suitable airport for repairs; too bad for the jet and pilot needing fuel. The KC135 and KC 10 lose an engine and they stay on station to perform the mission and then go for repairs. Yes the KC135 is old, but no older than the B-52, still in service.
    3. My opinion of the 787 is that Boeing was trying to show it could also build a plastic (composite) airplane just like Airbus. A stupid reason to switch from established success with aluminum airplanes!

    • Ad. 2: don’t overestimate the tanker. USAF needs a cargo and troop mover air first. That’s the reason why KC-135 gets that old: a one trick pony. The far newer KC-10 fleet is nearly through with its air frame life time due to dual use.

      KC-46 will be a far better aircraft for USAF without rubbish than KC-135. I still think KC-45 would have been far superior than KC-46 because A330 is a far better freighter/airliner than 767 – the cheap freighter to keep the 767 line open are misleading. Look how many airliners Airbus sold instead.

    • They went through that stage…blaming the crew and their training.
      Its not as simple as you think, and been discussed at length here in previous posts. The manual controls for the stabilizer trim -‘the wheels’- arent really workable at the airspeeds the Ethiopian plane reached. Thats why they turned the MCAS off but then turned it back on again.
      Since then simulations- using a properly configured Max simulator- have found that even highly trained crew knowing what will happen are marginal in getting back to a stable plane within the distance above ground they had.

      If you had kept up with the discussion you should know all this

    • Is this actually the best muthpiece Boeing can bring forward as “counterveiling” propaganda?
      On par with that Loren Thompson screed referenced elsewhere here.

  13. Boeing must get it right. If the Max begins flying again, and within a year or two another incident happens, with roots traced back to bad Design and Engineering by Boeing, the 737-Max is done for. Boeing is done for. They have handled this max crisis beyond poorly.
    The total lack of transparency and accountability has lead to public mistrust. A recent ‘computer glitch’ by an internet company named “Cloudflare” caused a large portion of the internet to go dark, for almost an hour, in the beginning of July. I was not expecting to hear any more details, as computer firms tend to keep quite mum about their errors. I keep wishing there would be an NTSB type of investigation of the Computer
    Industry errors, to help learn from other’s computer glitches. I was very surprised when Cloudflare came out a few weeks after the incident with chapter and verse describing the problem in minute detail and their remedies. Complete transparency and accountability. I respect that.
    If another 737-MAX incident happens, no matter what the cause, the flying public won’t listen when Boeing comes out and says “we can fix this” or “it wasn’t our fault”. They will have lost all credibility, and trust because of their lack of candor and legal stonewalling.

    • Boeing can try all kinds of software tricks but if an MAX goes down again for whatever reason the basic flawed design will come into play.

      Makes me think of an 60 year with thick layers of make-up, only surgery could fix some issues (for the short term).

  14. Boeing with the, knowingly Blunders committed on the B737 MAX’s will bare many Negative consequences for their future Image and Guarantors of their products. Their Rhetorical Propaganda Machine has gone Silent for years to come, regardless of the B737 MAX Patching outcome.

  15. My crystal ball has been very good on this.

    A week after the Lion Air crash I said the 737 MAX should be grounded. Why? Airplanes don’t do that unless there is something very wrong with the airplane. To turn it round, software doesn’t do that unless there is something very wrong with the airplane. So either way there is something wrong with the airplane.

    After the Ethiopian crash, the 737 MAX was grounded. One crash too late for me. At the time, I said the 737 MAX won’t return to service this year.

    So this is my current prediction. It’s going to get very, very nasty. Boeing will try and push a return to service on software changes alone. I think many regulators will say no. We will then witness the strong arm tactics.

    But crystal balls aren’t always right!

    • You also claim the 737 MAX is unstable when in fact you are wrong.

      I currently see no one allowing it back into the air until all the reasonable AHJ issues are addressed.

      And the big one has nothing to do with MAX, its the manual trim debacle.

      Properly executed software deals with anything else brought up.

      • @TransWorld

        Last minute implemented MCAS rather indicates that MAX has pitch stability problem, don’t you think. NG doesn’t have an MCAS but it is “same” plane.

      • TW

        I don’t use the word “unstable”. I use the word “instability”. They have different meanings.

        You are wrong, as always

        • Ahh, glad you could correct me.

          You were right for all the wrong reasons. Congratulations. Nostre Dommes (sp) of our time.

          Sometimes known as a dice thrower.

          • No. It’s pitch instability, whether you like it or not!

          • @TransWorld

            “I wish you would not fall to calling stupid names.” – your own words from today.

          • @Pablo

            Don’t worry about it. When I called for the 737 MAX to be grounded after the Lion Air crash TransWorld was far, far worse than above.

            TransWorld doesn’t understand that a software fix won’t fix the underlying problem of pitch instability. It will still be there.

            The question is can it be controlled by software? Boeing’s first attempt killed 346 people. Will the second attempt be any better?

            It is going to get nasty.

            By the end of the year, Boeing will have $20 billion of AOGs and the airlines another $15 billion. About 700 AOGs in total.

            Boeing are daring the regulators.

            If the regulators insist on hardware/mechanical/aerodynamic changes, Boeing and it’s suppliers are in real trouble.

            It will take a strong regulator to say no to Boeing. In other words, Boeing are saying to the regulators agree or else!

          • @Philip

            I prefer to see a good argument or even a bad argument but an argument.

            Yes, Boeing is challenging regulators – it’s a bad sign both for the airframer and passengers. Arrogant tactics. I hope EASA, Canadians and Chineses will be strong towards Boeing, for Boeing’s good.

  16. You make your own breaks.

    Some years back we had to do a pre check of a scanning system (30+ scanners and printers). If you did the check, maint as needed then you had few if any problems.

    I did the checks per standard.

    Another guy did not and was always complain “how lucky I was on my shift” because I never had any problems.

    Boeing has put themselves into this position by being stupid.

    Much like the 787 any time there is a tiny issue it gets blown up.

    If they had not mucked up MCAS then they would have smooth sailing.

    They don’t deserve a break. Just like the guy who did not do the checks on the scanners and printers, you make your own luck.

    Sure bad stuff happens, but it happens a lot more to the stupid and it happens more when you don’t react the right way when you have the chance which Boeing did not.

    So yes they likely had the Flydeal and Flydeal has no incentive to get stuck in with the MAX mess so exited stage right.

    So, while technically some of this is nonsense, they shot themselves in the foot and frankly its the only way now that real corrections will get made.

    Frankly I doubt it, they did not learn from the Lauda Air, the 737 Ruddeer, the 787, the MAX, so its going to take a major blow up corporate wise and I am skeptical.

    A CEO change does not do it, it needs to clean the rot out top first down to the middle levels. Find the people that have integrity, they are there, they are just cowering.

    • Those people with integrity are there indeed, by the fistful – and they are not merely cowering, they feel badly let-down by their company. OK, so Boeing “may deserve the whack they got/are getting”, but it is those people with integrity – the majority at Boeing – and their families who do not deserve the whack THEY’ll get if all this goes belly-up. Boeing should start nurturing them, not increase their risk of becoming victims of ‘friendly’ fire…….

  17. If Boeing can’t sort this out by very early next year the airlines won’t be able to get the mess cleared up in time for next summer’s peak season, this will be the point where just muddling through is no longer an option. It’s obviously not just the aircraft that are grounded or undelivered but also those due to be built in the ramp up that never happened.
    I predict good times for engine maintainers of older narrowbodies.The nightmare scenario would be changes for the NG,although I think that it really is too big to fail and has statistics on its side.How would banning women and small people from the flightdeck on the grounds of lack of strength go down?

    • Well they could just shift back to making ALL NG! (I don’t think they are fully converted over)

      Wouldn’t that make for a mess.

      This should not have even gone to the NG era, classics should have been the last of what was good bird at the time (sans the crank aspect and the rudder issue)

  18. Ken
    July 15, 2019

    Compared to the certification the 777-300ER, the 777-9 has:
    – new fuselage (bigger relocated windows, materials, lenght)
    – new cockpit (more like 787)
    – new tail (dimensions)
    – new wing (shape, materials, tips)
    – new engines
    – new engine mounts
    – new landing gear

    If this isn’t a series of significant changes that warrants a new type certificate, what is? Grandfathering rights have taken to new heights, risking missing out on changed system interfaces and dated requirements.

    Who approved this approach & when? Point of no return? Was it really the FAA and what was the goal? Safety first?


  19. Could the 330NEO actually “benefit” from the MAX situation? Boeing possibly will have to drop MAX prices even more putting pressure on what prices the 787’s could be sold for. If AB sharpen their pencils on the 330N prices and with spare production line capacity we could see some “unexpected” sales.

    • I doubt that Boeing price drops will be good news for Airbus sales campaigns. But at least Airbus has a full range of aircraft types for sale that can generate revenue. Boeing currently doesn’t.

      Another aspect is that Boeing could throw in the towel on the 737, skip a generation of sales as a result (ok, that’s a big “ouch”), and develop a proper 737 replacement and competitor to the A320 family. If they started, say, now, they’d be flying in, what, 5 years?

      Airbus would have to respond. Yes, they’ve got a ton of sales booked for the A320 family. But when Boeing announced the MAX, Airbus likely strategically banked a good few additional years of unchallenged A320 sales beyond even those. Boeing being forced into a NSA strategic change will also force Airbus into a strategic change, and one they likely weren’t expecting to have to make.

      Arguably, Airbus should be reacting to the trouble in Boeing as if Boeing will end up doing the NSA early. If they do, and they beat Boeing to the draw then it simply reinforces Airbus’s position. If they don’t, and the rest on their laurels for only a short period of time, they could find themselves reacting in haste. Which is exactly the circumstance that has got Boeing into its current prediciment.

      So the message is simple. Develop, or die. Boeing didn’t develop, and will die unless they get serious about their long term future. Airbus has done a whole heap load of carefully considered development, and it’s paying off. Stopping now is probably a bad idea.

      • Fore-going over 2oo billion dollars in sales is not necessary and would decimate the company. The plane will work and had already flown millions of passenger miles. Now I am not saying the two crashes were an anomaly, the MAX has a flaw. But it appears fixable. Boeing will move on to the NMA before starting a NSA, but the latter will come sooner than originally planned. They probably feel they have to do that NMA seeing Airbus’ success with the A321XLR.

        • Sam, this whole debacle is already decimating the company. The plane currently does NOT work and while flying millions of passenger miles it has also killed everybody aboard two of the same. Is it fixable? Certainly. Is it fixable in a quick and easy way? That was the original assumption a long time ago. We now know that the fix will be complex. Will it still be possible to apply economical? That’s not sure at all. What if the MAX needs not only a software fix, but also a new CPU, new trim wheel or possibly an entirely new speed trim system? Maybe a new stabilizer and/or elevator? Maybe even that will not suffice and we need a taller landing gear and a shorter, lower pylon. Reworking all the new built plans might cost as much as building them. Then what? The scrap yard? Chapter 11?

          If I was in the drivers seat I would stop production of the MAX asap. Build some NGs at a low rate, maybe 20 per month, to bridge both airlines and the production line while starting the fastest possible development of a new single aisle plane. By using the existing plans for an NMA, the 787 cockpit and sticking to all-aluminum and existing engines, it should be possible to speed up that process to the max and still (slightly) outperform the A320.

          Even if the MAX fix would not be as extensive as I’m speculating, I feel it is “burned” as a product. Boeing will receive many cancellations in the near future, especially when Airbus increases production of the A220 and A320 and airlines like Southwest and Ryanair have reset their fleet strategies. There is also a good chance that demand for planes might drop quite a bit soon (global warming, CO2 taxation,…), which will leave the lesser plane in a terrible position.

          If Boeing has ever NEEDED a new plane then it is now, and it’s not a fancy funny NMA with oval fuselage, non existing engines and non existing production systems, but a straightforward NSA.

          • I agree with everything you say technically… especially the statement about (demand for planes might drop quite a bit sooner (global warming, CO2 taxation,…)) But reality tells me in this “era of international business,” The MBA philosophy “Trumps” engineering no questions asked. The spreadsheet tells the bosses they’ve got X amount of dollars in that old piece of aluminum and we’re going to get our money out of it. They might have to do more than the MCAS software patch, but I think at the end of the year she’ll be hauling passengers for all SW, AA, UA, etc.,… “It’s not personal, it’s only business.”

          • Well, if the MBA philophsy is always going to trump engineering judgment inside Boeing, then the company is doomed.

            There’s significant risk that the MAX won’t ever fly again; significant in that the impact is really very high, and quite likely (even these hallowed reporters have admitted that this is unprecedented – all bets are off). The MBA philosphy is to ignore such risks, and not pick a strategy that doesn’t have those risks, which is why they’re going to come a cropper big time, and probably soon.

            I’m with Gundolf here; though I’d say the time at which Boeing needed an NSA was 25 years ago. What the MBA types won’t do is admit that Airbus has, quite a long time ago, made off with a large fraction of Boeing’s market share, and that Boeing as done almost nothing to counter it. It’s all very well sitting there saying “our profits are good”, when in fact the profits are miserable in comparison to what they ought to be had Boeing been bothered to keep its technical dominance over everyone else. $200billion on that old aluminium tube? Should have been $trillions in a carbon fibre one 20 years ago.

      • Airbus has also made a brilliant investment in what all seem to say is a state of the art aircraft designed from the bottom up: The Airbus A220, previously known as Bombardier CSeries (or C Series). I think there is also a larger A22-300 in the family. The aircraft is built with composite materials and has the best fuel efficiency out there. As some have said, the biggest challenge facing Airbus is supply. But it even seems that Boeing’s strategy of contracting out a lot of its construction has probably led to there being suppliers out there who may be capable of pivoting to another company and might be happy for Airbuses business. Boeing and Southwest made a short term calculation about 15 years ago. It’s time for some to see that driving everything on quarterly profits has disastrous consequences in the long run.

  20. Duke, if you change the size and location of the windows, change dimensions of frame cross sections, use third generation aluminium-lithium (Al-Li) skin pannels and stringers, change over fuselage lenght and tail / wing induced loads, in my opinion your existing (77W) strenght and fatigue FEM models need to be redone and processed all over again. A significant change from a certification standpoint.

    The FAA was firm on grandfathering dsign and requirements 20 years ago. But apparently they had a change of hearts when the 737 MAX and 777X were needed fast.


    Combine that with the increased, congress pushed, delegated / efficient certification and we had an inflamable certification frame work moving forward.

    Interestingly, the folks looking into this were part of the process & this is starting to look strategic. I hope politics can stay out and objective legislation in. .

  21. I read this in a media outlet, re Airbus going back on top again in terms of deliveries.

    “The loss of bragging rights also could translate into lower cash flow and sales of services to airlines.”

    • Its not the bragging rights, its the fact that lower deliveries means no cash.

      While its not possible, I would take the deliveries over the bragging rights any day of the week.

      BCA now has one cash generator and its hurting big time.

  22. My take on the whole MAX issue is that this design represents a HUGE departure from “best practices.” A passenger plane with zero inputs should default to approximately straight-and-level equilibrium. It’s one reason most planes have a dihedral angle, so that in a bank, the no-input response is a roll in the opposite direction. The MAX with no input is inherently unstable. It will pitch up until stall conditions occur. Even if Boeing is able to perfect the software, what happens if a lightning strike destroys the electronics running that software?

    The MAX is an ill-conceived rapid response to the NEO. I am a fan of Boeing and its long history IS the story of civil aviation, but this kind of departure requires a much deeper review than just talking about sensors and software.

    • Even bringing up the Airbus problems in this context reveals very flawed (pr campaign produced) thinking — indeed it inherently points to the acceptability of a software solution to the Max’s problem. But the Airbus problems were caused by faulty sensor readings and the response was tweaking software in flyby wire systems that completely depend on sensor readings. The Airbus did not naturally have a tendency to pitch up into a stall. The Max’s problems were not fundamentally caused by faulty sensor readings or software problems. They were caused by the cascading problem of trying to resolve fundamental aerodynamic instability with a buggy software patch.

  23. Scott is confidently predicting at the end there that the MAX will be back in service next year. I’m not convinced there’s any evidence to suggest that that is achievable.

    I’m very suspicious of that recent failed test by the FAA. Effectively Boeing didn’t do a test (or didn’t do it adequately), and the FAA did. Caveat – I’m making a large assumption that the testing strategy was for Boeing to be confident of passing having run their own test plan before presenting it to the FAA, rather than using the FAA as a means of doing the debug testing. Using the FAA for that purpose feels, well, unlikely. Caveat not withstanding, that means there’s been a discrepancy between Boeing’s view of the testing requirements, and the FAA’s view. The consequence of that can very easily reek total havoc with a design and implementation. Fixing it might mean starting again from scratch.

    If my assumption is correct, that raises another question; what else have they missed? Did the FAA do every other test they thought applied, and it passed all of those, or was this one so bad they simply stopped the test plan there and then, unfinished, to give Boeing the bad news?

    There is a financial clock ticking on all this. Boeing are not getting any revenue from the MAX at all at the moment, the costs are unchanged on production, there’s storage costs, and there’s the fallout from the tragedies to pay for too. The reserves aren’t going to last forever. How far are we from their next due financial results? Those could be very revealing.

    If my assumption is incorrect, corrections most welcome!

  24. There is two aspects, which I am curious to find out about:

    * How will this all affect Boeing’s Balance sheet and Cash Flow
    * what will be the cost for compensating airlines not being able to use their Max’s

    Given the limited supply of competing aircraft, Boeing will be able to sell and deliver 737 Max after all this is over. Unless they totally screw up and won’t get it rectified

    Boeing has spent tons of money to buy back shares in the last years. Their equity is almost zero to begin with. How much money does it cost them, to produce one of these parked airplanes? Do they have to pay for all the Leap engines on those now, or does CFM have to wait to delivery? 42 aircraft per month since March are adding up quickly. If that goes on, aren’t we talking about 360+ parked planes by the end of the year. That is quite some capital bound on the tarmac.

    How much will airlines get in compensation and how much will be visible in the Financial Statements short-term versus lower income for future business?

    While I don’t think this disaster will kill Boeing it will have long term effects and hopefully will result in a change of the future corporate policy

  25. You can be sure CFM does not deliver engines to B unless it is paid as per contractual terms.
    Assuming a cost to produce one aircraft of about $40 MM, having about 400 sitters parked around we are looking at an inventory number of $ 16 BBs by year end, and growing at a rate of $ 880 MM per month, a lot of cash indeed… Add to this storage costs and we get to real money.
    Of course there might also be significant rework costs down the pike to swap computer chips, rewire switches, accommodate bigger manual trim wheels, even – Heaven forfend – modify tail units to incorporate larger elevators, etc….
    Will banks consider this sitting inventory good collateral for a bridge loan? At what coverage ratio- 120, 150, 200 percent?
    The quarterly filings to the SEC will reflect this.

  26. The share buy backs and the enormous free cash flow at Boeing mean that the shares have increased in value 1,300% since 2009.
    Wall St likes share buy backs as unlike many other countries dividends are double taxed by the time they get in shareholders hands so only a couple of billion is dividends the rest is share buybacks. ( $9 bill last year).

    Dont believe the shareholder equity being near zero, as under GAAP rules , the $100 bill or so its spent over the years on its current in production airliners ISNT counted as an asset.
    (this story was before the Max grounding but the free cash flow is still valid, especially as under accounting rules those parked 737 Maxs are counted as ‘cash in hand’)

    • @Dukeofearl
      the parked 737Max are only able to be activated at cost I think, so that would by definition not be free cash flow

      In general, I am afraid the one-sided focus on share buybacks instead of long term investments will eventually fire back. The cycles are very long, Boeing is generating its cash with an airframe developed over 40 years ago.

      I do not see, how your link counters the fact, that Boeing is a nearly zero equity company, i.e. highly leveraged. Add to that program accounting, which is basically activating hot air, which will hit future profitability (not cash flow)

      • Car companies do the same , once its out the factory door and into the supply chain its counted as ‘cash and cash equivalents’ apparently because they are ‘orders’ and we know Boeings Maxs all have an airline livery for the customer who ordered them.
        At any time, even before the Max withdrawal from service, Boeing would have dozens of planes outside the plant awaiting final delivery, another example would be the KC46s ‘on hold’ for USAF.

        We we be able to see the numbers when the Q2 figures come out next week

  27. @Philip
    Excellent summary on what Boeing is doing right now. “Boeing are daring the regulators.” There’s not been a peep out of Boeing, as to what fixes they are working on
    or testing going on. A week from today, Wed July 24th @ 7am New York time, Boeing has an Earnings release. I assume some investors will ask some questions soon after that.
    I hope we hear some encouraging words from them, on how they are planning and executing the fixes. Silence will speak volumes, if they don’t at least have a high level plan scoped out.

      • https://www.flightglobal.com/news/articles/analysis-how-airbus-fought-its-own-pitch-battle-457574/
        Well worth a read
        Covered incidents with both A321 and A330 models
        ‘Simultaneous jamming of two angle-of-attack sensors, and the rejection of a valid third, had previously led to the fatal crash of an A320 during a check flight at Perpignan in November 2008.’

        The changes Airbus made:
        ‘Airbus nevertheless redesigned the angle-of-attack algorithm to prevent a recurrence of the Qantas incident, and improved the flight-control computer to enhance its ability to detect multiple angle-of-attack sensor blockage.

        The A330 and A321 blockage incidents led EASA to order removal of specific angle-of-attack sensors and their replacement with less susceptibility to adverse environmental conditions.’

          • Yes but its not really new ,and your reference was ‘ jumbled’

  28. This comment is response to Philip’s comments posted earlier in this section.

    Here is a definition;
    instability – lack of stability; the state of being unstable.

    I’ve never encountered a case in engineering where the term instability (or lack of stability) was used to describe neutrally stable. I’ve only ever seen it used to describe something being unstable. So, instability indicates something is unstable. When you use instability in the context of aircraft pitch, you are essentially saying the aircraft is unstable in pitch, whether you’re talking about the entire flight envelope or just a small portion of it.

    Now, I’ve not seen a single credible analysis that concludes the 737 MAX is statically unstable in pitch over any portion of the flight envelope. All the credible ones (not hit pieces written by people who may be pilots but have no experience whatsoever with aircraft stability and control at an engineering level) say things similar to what Bjorn has already written, that MCAS was needed to compensate for a sudden increase in ∂CMα/∂α at high pre-stall AoA (∂CMα/∂α is the slope of the aircraft pitching moment response, CMα, to aircraft AoA, α). The corresponding sudden reduction in stick force (to maintain pitch attitude) could lead to pilot overcontrol when the aircraft is already uncomfortably close to stall. MCAS changes the aircraft trim so the pilot feels the expected higher stick force when maintaining a high AoA attitude. I would call this a pitch stability issue, or even problem, but not instability or unstable. Remember, there are degrees of stability where something can be less stable than another thing while both are stable.

    Some have questioned the need for changing the aircraft trim, wondering why Boeing didn’t just mechanically increase the stick force to provide the expected control feel. The reason is that additional downward trim configures the aircraft for quicker stall recovery in the unlikely event that the pilot takes it there. Mechanically increasing the stick force does nothing to help the pilot in stall recovery. I believe the intent of MCAS was to serve both of these purposes.

    You and a few others in the LNA comments section seem to be convinced that the 737 MAX is statically unstable in pitch. As far as I can tell, the reasons cited range from; MCAS was a hastily applied bandaid late in flight test; to Boeing is not revealing all the details so they must be hiding serious deficiencies; or the extreme outcome due to MCAS during the crash flights must mean that extreme aerodynamic shortcomings existed with the aircraft. None of these reasons are based on actual physics or engineering. They are instead attempts to find cause in the face of sparse information by reading between the lines of press articles based on second hand info at best and re-explained by authors with little to no understanding of the aerodynamics involved (not including Bjorn Fehrm, Peter Lemme and a few others I’ve found).

    The 737 MAX is statically stable in pitch and I think that MCAS, if implemented soundly in the current hardware, will correct the pitch stability issue at high AoA.

    • Mike, I’ve been trying to figure out the dogged instance of Boeing to implement MCAS.
      Is it a ‘feelability’ issue .. or ‘stall protection’ … Why at high AOA, pre stall does the 737 suddenly want to pitch up so much more quickly? The big frontal surface area of the new engines flipping from under the wing to over the wing … does that cause a jackknife type of effect in pitching up the aircraft? What about these two AC crashes (737’s of older design)?
      both were in the ‘go around’ phase .. 737 pitched up .. or was pitched up by the pilot, flaps changed settings .. and suddenly they went nose down into the ground. I don’t know what stabilizer setting these were at, but, I assume landing mode. Maybe these events were wind shear? sudden tail wind?
      If Boeing is trying to get the feel ability correct, then apply the force to the yoke ..
      (your comments about the reason Boeing does this below)
      this confuses me .. if it’s feel-ability .. then yoke force should take care of that ..
      but, is it a training issue? Pilots are not trained well for go-a-rounds? Or is it a 737 high AOA pitch problem? The ‘jack knife’ effect, of at high AOA the plane is less stable and wants to suddenly flip pitch up? Excellent piece by AA on wind sheer recovery .. don’t try and recover from a stick shaker in wind sheer at low altitude .. but, concentrate on not flying into the ground first … MCAS seems to completely ignore that advice
      So is the ‘instability’ just in the stick force? That just doesn’t sound right to me. If you take your hand off the controls at high AOA .. the plane will recover by itself? As it should if dynamically stable? Or will it continue pitching up, eventually into a stall?

      • Richard:

        The view that 737 MAX pitch instability is limited to the pre-stall regime is wrong. Commercial airplanes must never go there. It’s too late. Yes, in the pre-stall regime stick forces become woolly but that’s because the control surfaces becomes woolly. The consequence is that the airplane is at the mercy of mother nature; one gust of wind and it’s gone. So never go there.

        The question is where does the pre-stall regime begin. This comes to the nacelles. They are glued to the wing. The effect is to extend the mean chord of the wing forward. This moves the CofL forward, but the greater the AoA the more the CofL moves forward.

        In my view the forward movement of the CofL accelerates with increasing AoA. This causes the upward pitching moment to accelerate. In turn, this causes the nose move up faster and faster.

        The issue is inertia. Once the upward movement is there it is hard to stop. Hence the very aggressive use of the stabiliser. But it must be stopped before the pre-stall regime for once there it’s down to mother nature.

        So, to address the word ‘sudden’. The word isn’t ‘sudden’, it’s ‘acceleration’. As the AoA goes up the more the nacelle contributes to the lift causing the CofL to accelerate forward and therefore the pitching moment to accelerate up.

        The bad boy is inertia. Once the momentum is there it is hard to stop. That’s why MCAS 1.0 puts rubber on the road.

        Bottom line. I think the 737 MAX has a very narrow envelope in pitch. The question is: Will pilots be able to keep within the envelope?


        Systems that exhibit instability are not necessarily unstable.

      • Hi Richard,

        Good questions! Since you posed them within a response to my comment, I’ll take a crack at answering them. I’m pretty confident in my answers to the following four questions because I’m very sure of two things related to the 737 MAX longitudinal stability; that it is statically stable at all AoA’s even through stall; and that it is less statically stable (but not unstable) above some high AoA than it is for lower AoA’s.


        No, I agree with you that the issue is not just with the stick force. The 737 MAX has a longitudinal static stability issue at high AoA’s. This issue presents itself at both high and low speed. Since the primary flight control surfaces on the 737 MAX are mechanically controlled by cables, the stick force in pitch is directly affected by the aircraft static pitch stability. Because the aircraft is less statically stable in pitch at high AoA’s than at low AoA’s, the stick force required to change aircraft AoA in both ANU and AND directions is lower than it would be if the pitch stability was the same as for lower AoA’s.


        The 737 MAX will always recover back toward the trimmed (equilibrium) condition if the pilot releases the controls at high AoA’s. This is because the 737 MAX is statically stable in pitch for both low AoA’s and the high AoA’s that MCAS was intended to affect. Both static and dynamic stability are important, but if an aircraft is statically unstable in pitch, then it can never by dynamically stable in pitch. Longitudinal static stability is a necessary but not sufficient condition for longitudinal dynamic stability. Of course, I’m assuming here that the aircraft is in its “natural” state, without any closed loop control system to provide artificial stability.


        Yes, the 737 MAX does have a static pitch stability issue at high AoA, namely that it is less stable beyond some high AoA than at lower AoA’s. However just because the slope of the moment curve increases, it doesn’t mean that it goes all the way from negative (stable) to positive (unstable). It means it just gets less negative which means less stable but not unstable. As long as the MAX is statically stable in pitch, it will not just suddenly pitch up when the pilot flies it beyond the “hinge in the jack knife”.


        As far as I can tell from the info I’ve been able to access, the original intent of MCAS was twofold:

        Maintain a smooth increase in stick force through the slope change in the pitching moment vs. AoA curve
        Configure the aircraft in a way that will allow faster stall recovery.

        Both of these help satisfy different aspects of FAR Part 25 – Airworthiness Standards: Transport Category Airplanes
        Sec. 25.173 — Static longitudinal stability
        Sec. 25.175 — Demonstration of static longitudinal stability
        Sec. 25.201 — Stall demonstration
        Sec. 25.203 — Stall characteristics
        Whether or not MCAS is a stall protection or anti-stall device depends on ones definition of those terms. As I understand it, MCAS will not prevent a stall as the pilot can still fly the aircraft into a stall, but doing so with MCAS will be more difficult than without it.

        I’m not as sure about my answer to this last question because I couldn’t find much credible information that goes into the details of the aerodynamics. I’m giving this my educated guess.


        At high speed the higher placement of the engines causes the supersonic (low pressure) portion of the flow over part of the wing to move forward when the AoA is high. This causes the overall wing center of pressure to move forward resulting in an increased pitch up moment contribution from the wing, sort of a mach tuck situation in reverse, but only at high AoA’s. I suppose that the lift generated by the engine nacelles themselves, being larger and placed more forward, also contribute an increased pitch up moment relative to previous models. Are they really that much larger and more forward though?

        What about at low speed? This is bit of a head scratcher for me. It could just be due to the lift from larger nacelles placed further forward than on previous models. Again though, are they really that much larger and more forward than before? I don’t quite buy it. There is something non-linear going on, I just don’t know exactly what it is.

        • Mike, Thank you for taking the time with your excellent reply. I must say that the folks on this website are very knowledgeable, and at most times, very civil in questions and answers. I really appreciate that. And I’ve learned a lot.

          • Richard,
            Thank you for the kind words.

    • Yes! Mike Bohnet this is just the sort of can-do American attitude that Boeing needed 15 years ago when executives took the lazy easy way out (something they would never tolerate in workers making 1/600 of their salary) and went with shoving new, better performing engines on a 50 year old plane. Still, though I am not an engineer and can’t make any sense ∂CMα∂αAoA ∂CMα∂αCMαAoAα, nothing I have read indicates that this was in any way a prudent decision for airliners that fly constantly for long hours for decades. As one person said in another blog; it’s a good decision for an aircraft that provides parachutes and an ejection seat. Fighter planes might be designed along these lines, but they don’t typically fly as long and they are subject to intense mechanical attention when they land. One can quibble over the term “aerodynamic instability” as defined by engineers or laymen like me trying to grasp an issue that will affect all of us. The aircraft may stably and beautifully fly up into a stall, or one of its wings might stall, spiraling it in all of it’s stability into the ground. There is so much not said and hence so much unknown that few of us can really assess the cascading consequences of violating aeronautical engineering norms for passenger planes and fixing a physical anomaly with a software patch that is constantly subject to human error and not the laws of physics. Perhaps the term “divergent condition” is better. I’ll let the engineers argue this one out. As a layperson, I love the idea of the Boeing which still allows pilots to have physical access to control surfaces. I hate the idea of fly by wire. But in 2019, the redundancy of fly by wire systems and software and its unprecedented safety has made the Boeing hybrid an archaic anomaly. I felt strangely patriotic when I learned that what befell Air France Flight 447 might have been resolved by the connected yokes of Boeing airplanes. And I felt let down when I learned that ‘Sully’ had guided his airbus safely to the Hudson River on an Airbus that used video game joysticks. No one is helped by looking at this issue through a patriotic desire to save jobs and the cloud of ideology. We need to see the decision to modify the 737 endlessly for what it is: short-sighted naked greed.

    • Mike Bohnet, Philip, Richard

      There appears to be a lack of trust of both Boeing, and the FAA at the moment.
      This is an ideal space for conspiracy theories to flourish.
      Due to the lack of clarity, openness, and evidence, it’s also an opportunity for interested parties to ask sensible questions.

      Bjorn in his corner, Pitch stability, Part 9, posted a thought pitch moment curve for the MAX. https://leehamnews.com/2019/02/08/bjorns-corner-pitch-stability-part-9/
      I do wonder what the actual pitch moment curve looks like, not the projected one, but the actual verified one.

      We now believe that MCAS was originally implemented to address one area of the envelope, and subsequently used to address another different area of the envelope at lower speed, necessitating faster, and greater stabiliser movement.
      Two different areas of the envelope !

      From https://www.nytimes.com/2019/04/11/business/boeing-faa-mcas.html
      “Last month, during flight simulations recreating the problems with the Lion Air flight, American pilots were surprised at how strong MCAS was”

      So the question; Why was MCAS so agressive in the original version ? What has changed that the proposed (and tested) later version does not need to be so agressive ?

      There doesn’t appear to be any evidence in the public domain that the 737 MAX is unstable in pitch, but neither is there any evidence that it is stable in pitch.
      Only the engineers, and test pilots at Boeing will really know exactly how stable the aircraft is without augmentation.

      Regarding Flydubai 981, weather, and pilot fatigue may have influenced this accident. The following two lines from Wiki are interesting:

      “The pilot flying then pulled back on the control column, which increased the vertical speed to as much as 16 m/s.
      At a height of 900 m, there was a simultaneous control column nose down input and a trimming of the horizonal stabilizer to a nose down position, from -2.5 deg (6.5 units) to +2.5 deg (1.5 units). The FDR recorded that nose down stabilizer trimming, from the stabilizer trim switches on the control wheel, lasting 12 seconds. The CVR also recorded the specific noise of rotation of the trim wheels, located on both sides of the central pedestal.”

      In the line above this, it states that TOGA power was set. Was the PF startled at the acceleration of pitch up of the aircraft, startled so much that he felt he needed to both push the nose down with the control column, and trim the stabiliser nose down ?
      I can’t think of another reason why a pilot would push the control column forward, and trim nose down at the same time at just 900 m.

      When designing complex systems, we really must take into account the human factors !

      • The reason for MCAS. It’s not for feel-ability. You could accomplish that by loading the yoke as the elevator feel system does in the 737 now. As for stall avoidance, then you have to figure that in the high AOA segment, the plane wants to pitch up, because of the more powerful engines, and their placement. The moment of the weight, along with the bigger fan size diameter, and higher thrust, causing more upward force than before. So, the elevator wasn’t changed to counteract this larger force. Some thickening of the Stabilizer. But, the real change to counteract the larger force was MCAS. It sped up the Stabilizer, to make it act more like an elevator. It seems to me to be unstable at high AOA. If one were to get into MCAS activation region, without MCAS and took your hands off the controls, would the plane return to level flight or pitch up more and more? I think that’s why MCAS is there. I’m not suggesting the 737 is as unstable as an F-16, but,
        in that one high AOA region, for whatever reason, it seems to be unstable. As ‘unstable’ is explained in this short 4 min video
        And, why? oh why did Boeing change the trim switch cutout wiring to not allow manual control of the stabilizer without Autopilot? If they want to build a full fly-by-wire system, then build one. MCAS isn’t that. If MCAS 2.0 doesn’t fix that, then it has to be certified to FBW standards.

      • Hi JakDak,

        I would say there is lots of evidence in the public domain that the 737 MAX is statically stable in pitch. It is a cable controlled aircraft that has acceptable handling characteristics in the majority of the flight envelope wher augmentation is not applied. This would not be possible if the MAX was statically unstable in pitch.

        The original version of MCAS was made aggressive to handle the low speed augmentation. However, I think we can all agree that it was also not implemented correctly, so how much of the surprising aggressiveness was actually intentional.

  29. BOEING and the FAA are presumably working on various options to Patch an aircraft that has to go through extensive engineering correction on the multiple structural deficiencies cited by Engineers/Pilots/ other Aviation experts. BOEING/FAA have been pretty Silent lately on the Solutions they are working on. Whatever the outcome between these Two, the Rest of the World are watching developments with a Magnifying Glass and they can perfectly object to the final corrections and a Testing of the final product themselves. They will definitely not approve of the B737 MAX until totally convinced of testing results. EU, China, will be very strict this time knowing the Grandiose Lies and Deception BOEING has caused to its Clients/Passengers.
    Time will Tell, sometime in 2020, if not longer.

  30. Dear me.

    I’m not using the term instability to describe neutral stability. Neutral stability or neutral point is a technical term. Basically, it’s when the CofG and the LofG coincide. There are minor modifications to those words because airplanes are not symmetrical. See Wiki for details. For once, Wiki is very good for is does have a very good description of longitudinal stability, including positive, negative and neutral stability.

    The difference between unstable and instability.

    If a person stands up but immediately falls over that person is unstable. If a person stands up but remains upright but is unsteady that person has instability.

    This comes to external forces on the person. If a light push on a person causes the person to fall over the person then the person has major instability. If the person needs a heavy push, the person has minor instability.

    In terms of english semantics. Unstable is absolute. Instability is relative.

    I do use the term natural stability. That means a person prefers/wants to walk on two legs. In other words, it’s natural for a person to stand up.

    Perhaps you have mixed up the word “neutral” and “natural”.

    I use the term natural to describe an airplane that prefers/wants to fly straight and level even if subject large external forces. In other words it comes natually to the airplane to fly straight and level. It is an inexact term, but this site is not the place to write books.

    The question hanging over the 737 MAX is how much of a push is needed to make it fall over.

    I’ll leave it there. Not the place to write a book.

  31. A bit more

    Statically unstable and static instability are also different terms with different meaning, the term static being important.

    I suggest you look those up too!

  32. ‘Steve
    Sexism isn’t necessary. I’ve seen some skinny little male pilots out there with shoestrings for arms.. . . . ‘

    I was only using gender to make a point, after all there is a general acceptance that females are the weaker gender – a fact that is recognized in most sports.

    Sorry, I never intended to sexist’.


    • Few of us intend to be sexist. It’s like being ageist. When thinking about this issue, I always am in mind of a joke I read once in a magazine, where a man went to a doctor complaining about his knee. The doctor said: “Well, you gotta remember, that knee is 67 years old.” The man replied: “So’s the other one.” It’s sad how so man people can easily turn the issue of greed and failed leadership at a major corporation into the old saw horses of affirmative action, women’s inequality, and unfit brown-skinned pilots (reminding me of the arguments against African Americans being allowed to fly in WWII that dogged the Tuskegee Airmen). Aren’t we better than that?

      • Steve, and anyone else interested.
        Concerning African American airmen – a good read is Adam Makos’s book ‘Devotion’ which tells the tale of two Corsair pilots during the Korean War. One, Jesse Brown, became the US navy’s first black carrier pilot.
        This is an inspirational read.

  33. After all this, time for Airbus to move on with the A360, could EIS by around 2027/8 with Ultrafans, NSA 2035?

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