Leeham News and Analysis
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Leeham News and Analysis
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Look to 2013 787 grounding to see how Boeing will return MAX to service
By Scott Hamilton
Sept. 13, 2019, © Leeham News: As Boeing prepares for what it hopes is an imminent recertification of the 737 MAX from the Federal Aviation Administration, how it will handle the logistics of returning 381 grounded airplanes to service and delivering nearly 300 more undelivered 737s is key.
One need look to the only other time a Boeing jetliner, the 787, was grounded and how “One Boeing” coalesced to attack what was then its largest logistical task for its commercial airplanes unit.
The return to service of the 787 paled compared with the task facing Boeing today. In 2013, there were only 50 787s grounded worldwide after two lithium ion battery incidents: one fire and one near-fire, one on the ground and the other as the airplane took off.
In 2013, the production rate of the 787 was in the single digits per month. The 737 is being produced at a rate of 42/mo.
In 2013, there were a few score of 787s parked around Everett’s Paine Field awaiting delivery. Today, the nearly 600 737s are scattered around four locations in Washington State, a Boeing facility in Texas and various airline storage areas around the globe.
In May 2013, I wrote a freelance piece for CNN’s website how Boeing planned to return the 787 to service. This story may be found here.
The task at hand
Boeing today has been mum about how it will handle the MAX return to service.
It has publicly said it is hiring a few hundred temporary employees to be located at Moses Lake (WA), where more than 100 MAXes are in temporary storage.
These technical people will be tasked with “un-pickling” the airplanes: opening up seals on pitot tubes, air ducts, engines, etc. Making sure fluids are pure and all control surfaces work. Powering up the engines, APU. Making sure the airplanes are free of insects, rodents and birds. The list goes on.
Months of storage—the MAX was grounded March 13—complicate the tasks.
These technical people include retired Boeing employees across a litany of skills.
Marshaling One Boeing
In 2013, the task of installing hardware to contain possible battery fires and bringing back to life 50 787s was then described as tedious. New batteries had to be installed, new containment boxes installed around the batteries, new systems associated with the containment boxes added and an exhaust hole drilled into the bottom of the fuselage.
For MAX, the fixes to the MCAS and flight control system are software updates that will take maybe a few hours to download. As of today, no hardware fix is going to be required, although Europe’s safety regulator, EASA, says a third Angle of Attack sensor of some kind may be mandated.
Boeing Commercial Aviation Services, the forerunner of Boeing Global Services, took the lead. Personnel from Boeing Defense, Space & Security were loaned to Boeing Commercial Aviation Services and CAS.
“Because of the way the teams were going to have to be built, there were some very specific skills that were needed,” CAS CEO Lou Mancini told me in the 2013 CNN interview. “A good example would be engine run. Within AOG we have two engine run folks but obviously we were going to need more, so we did reach across the enterprise.
“We reached out to our BDS (Boeing Defense, Space and Security) counterparts. We reached out to our factory. We reached out to our avionics functional test guys and the Everett flight line people really helped. A vast majority of it came from the Everett flight line. They are as close to the same skill set as we would require.”
Dispersed around the world
Then, CAS had a team of 300 people in 10 teams dispersed around the globe to service those 50 787s. Boeing had to transport up to 30,000 lbs of tools and equipment, something not required for the MAX.
“This was on such as large scale, this is probably the single largest thing we had to focus on, the logistics behind being able to accommodate the movement,” Boeing said then. “We moved equipment sometimes several times to satisfy the customers.”
Returning the MAX to Service
Boeing doesn’t have the parts and tooling logistics for the MAX that was required for the 787. But the sheer number of airplanes creates a different set of logistics challenges.
The first MAXes returned to service will be newly produced ones from the Renton (WA) factory.
These won’t have been “pickled,” and the software upgrades should be installed during final assembly.
This is probably what Boeing CEO Dennis Muilenburg in thinking when he says the MAX could return to service in the early fourth quarter. Preparing the produced-but-undelivered airplanes for RTS and bringing back to life the grounded airplanes will take longer.
The level of pilot training required remains unclear and could affect the RTS.
Heaps of employment opportunities for Messrs Finagle,Sod and Murphy.
I wonder where one could apply.
Missing in the analysis is the fact that it looks like the USA will have back in service first
So the only immediate needs will be those MAX built for the US. The rest are irrelevant for now.
Do you consolidated them on one site to do so or do y09ou go around to all the stash sites?
It would make sense to put all the MAX for a given AJH jurisdiction in one location .
If China allows return before EASA then they will be next etc. Small countries will go with whoever they believe in or works (some likely with the US to get the aircraft they were counting on into service) .
the process of returning the MAX fleets ( either grounded customer planes or the still undelivered new builds ) is a Boeing problem.
that may be interesting to watch but it is a lesser problem.
Getting the go ahead for this is a global problem.
At the moment all indications are that Boeing/FAA/US will go for forcing the issue and trying to sidestep, bypass or intimidate the involved certification institutions.
It doesn’t really look like Boeing has done viable to certificate work on the MAX.
= = = At the moment all indications are that Boeing/FAA/US will go for forcing the issue and trying to sidestep, bypass or intimidate the involved certification institutions.
It doesn’t really look like Boeing has done viable to certificate work on the MAX. = = =
I do think that citations should be provided when strong statements of this type are made. But I guess that’s just my bizarre preference for confirmed facts over self-reinforcing speculation.
@ sPh
Anyone following the MAX saga closely knows that Boeing is trying to get away by providing a flimsy minimum-effort fix to a complex multi-layered problem. Time would tell if nature yields to the whims of the Boeing company or laws of aerodynamics bend to the elegance of Mr. Muilenburg’s tie in investor conferences. I would recommend reading a little more coverage and industry analysis before accusing others of “self-reinforcing speculation”.
Flimsy is the least of it. Boeing has not done one thing to remedy the Max problems. The whole mess involves both the airframe and the engines, which are to big and much to heavy for the old airframe. All of this has not been corrected and will involve another grounding in the near future if this Max is allowed to fly again. I hope it doesnt cost any more lives, but thats on Boeing conscience.
=== I do think that citations should be provided when strong statements of this type are made. But I guess that’s just my bizarre preference for confirmed facts over self-reinforcing speculation.===
That is difficult and you know it.
Obviously Boeing and their minions at the FAA, government will avoid spilling the beans in such a crude direct way.
That won’t change the desired and targeted outcome.
There is no way FAA – or Boeing – will be able to ignore the diktats of other regulators in this matter.
In the connected world of today the global and continuing PR stink involved would be unbearable and US airlines will not accept being labeled as substandard/third world operators putting US lives st risk for profit. Would a warning be required on boarding passes?😱
crash pics like on [cigarette] boxes.
potential frustration does not turn the strong drive towards trying to bypass other regulators nonexistent.
incrimination is in action towards not necessarily in final success .. or not.
This does remind me of all of the analysis leading up to the release of the Mueller report.
@Steve You are quite astute!
” I guess that’s just my bizarre preference for confirmed facts over self-reinforcing speculation”
I agree but this comment board is probably not the best place for you. It’s foundation is built on self-reinforcing speculation!
We will see how much works needs to be done after a year of storage 😉
BOEINGS problems are just at thee beginning stages, and the “Patchwork” on the B737 MAX’s does not seem to be the Ultimate solution to start flying and delivering these Birds, at least in the minds of Europe, China(check RT article on You Tube of 2 days ago with Sanchez) and India announcement yesterday.
It is inconceivable, that after BOEING’s experience with the B787 Lithium battery drama, they repeat a more dramatic and disastrous event, for the Sake of expedient Sales/Profits/Dividents.
Well, if the EASA does mandate another AoA sensor, Boeing won’t be unpicking those destined for Europe any time soon. Unless Boeing has been a whole lot busier than just a software update.
Matthew, That brings up an interesting question. If EASA mandates some sort of hardware fix (i.e. a third AOA sensor, along with the associated software changes). Then will that change be for all the 737-MAXs, or just “outside of the USA” 737-MAXs? Would there be a 737-MAX-USA and a 737-MAX-rest-of-the-world sub types? Or, maybe change the outside of the USA first, and then retrofit the retrofitted USA 737-MAXs? Boeing seems to be rushing these fixes out, before they know what they need to fix. They are putting the proverbial horse before the cart.
Yes Richard, that will be an interesting aspect to look into. If boeing decides to ignore the mandates of EASA and the rest of the authorities and create a USA only sub-type, there will probably be severe backlash from the 3 major American operators (AA, UA & SW). This will mean that they have to maintain 2 types of sub-fleet, ones that can fly out of USA and one that can only fly within. This will have severe complications to the airlines operation. It will reduce the flexibility and crew planning of the airlines as I would imagine pilots flying those with 3 sensors will have to respond differently from those with 2. Creating such a sub-type will cause the 2nd hand value of the aircraft to be almost zero as these sub-type can only be operated within USA. Airlines and lessor will be furious about this. So it is unlikely that Boeing will create such a sub-type in the long run. One possibly is that this sub-type will exist for a temporary period of time after the max returned to service within USA. However as the whole incidents comes to a close, you should expect boeing to rework these aircraft and install the necessary changes to be certified worldwide.
It does not need to be that drastic. Boeing certifies a Service Bulletine for a 3rd alfa probe and a software version that can handle both dueal and trippel alfa probes. The EASA issues an AD demanding that SB, the FAA does not. Hence when you move a 737MAX out of N-registrary the SB becomes compusatory and when moving into N-registrary it is just another SB.
It is an interesting point when one considers what those hardware changes could be.
AoA sensors. To add another means drilling holes, running cables, connecting it up to the computers, writing the software. If there isn’t spare interface ports on the computers for an additional AoA sensor then that means they’ll probably need a whole new computer.
At this point they’re in a whole world of pain. They’re currently running on an 80286 based machine. A new one won’t be. They’re then looking at having to port the entire software stack over to a new machine and start again on recertification testing. Worse if the other computer peripherals (displays, keypads, etc) can’t be made to work with the new computer they’re replacing all that too.
There’s a reason why smaller aircraft just fit an off the shelf cockpit. It’s a big big job to make one, or change one.
Trim wheel forces. The EASA is insistent that this be addressed. Doing something mechanical sounds difficult. To make the wheels bigger they’d likely need a whole new cockpit, and possibly a whole new aircraft. The wheels were shrunk for the NG to get everything else in. They’re constrained by the room available in the cockpit, and the only way to increase that is to increase the cockpit diameter.
Alternatives include different gear ratios. However that’s going to slow down the rate of trim change a pilot can accomplish by cranking the wheels. That then might not be acceptable for the purposes of correcting an MCAS runaway.
Power assist is another option, but isn’t that what the control column switches were for on the NG? Which Boeing changed on the MAX? It’s still a mystery to me why they did this but the assumption is that the aircraft aerodynamics are too bad (or at least too different to the NG) without MCAS. Assuming that they can’t reverse that change, they’ll need a supplemental MCAS if the primary one goes wrong. At which point they may as well clone the A320.
If the MAX aero free of MCAS can be certified (extensive pilot retraining, column forces in acceptable ranges, flight characteristics manageable, etc) then the easiest change to the aircraft is to restore the NG’s trim switch functionality.
If the aero is no good and a fully redundant MCAS isn’t an option, they’d then have to fix the aero. That’s a new set of elevators, a new tail plane, increased loading on the tail assembly, perhaps fuselage reinforcement, etc. It could be a massive job.
Basically some of the changes the EASA want are precipitously close to making Boeing build a whole new aircraft, because that’d likely be cheaper. Pity, as they’ve just gone and built hundreds of potentially unflyable aircraft. In effect Boeing has taken a massive bet in it being a software fix, and is probably about now realising that it isn’t.
Unless they can get away with minor wiring changes or additions, including putting in another AoA sensor into the existing computers, Boeing will probably go bankrupt as the CAAC, EASA and others are all likely to agree on what’s needed and it’ll take too long to make bigger changes. By focusing on what the FAA is saying, Boeing may have just sunk themselves. If Boeing were relying on the FAA’s view prevailing globally, then they clearly weren’t paying attention to how the MAX got grounded in the first place.
Boeing’s biggest brand was, in effect, the FAA, but the reputation of that brand has been questioned by the EASA’s officials and is being investigated 3 separate ways by the US government and prosecutors. Reliance on other countries’ good will towards the FAA’s reputation isn’t the safest commercial idea at the moment. Worse, if the FAA does go it alone and put the MAX back into the sky, the damage could be long term.
You get off tack with AOA, the system does not require more AOA I am not sure why you beat on it other than maybe confused between the 737 Cert and a FBW cert aircraft.
Manual Trim has to be fully Independence, I don’t know the AHJ answer to assisted as it would have to be seperte from all other failed system that could affect it.
Manual trim issue is the only item that there is not an answer for.
As it affect the whole 737 line as well as any other aircraft of that era flying its a separate aspect that touches on the MAX but is not the heart of MAX.
We are going to have to wait to see how the issue is laid out by the AHJ’s and what response is expected or allowed.
MCAS appears to be flight critical, as Boeing could have just ripped it out 6 months ago, but, haven’t. They even took away the ability of the pilots to turn it off. The two crashes seem to be focused on the AOA system. Quite possibly the sensors. Having a ‘vote’ between only two sensors can lead to a tie, and having a third sensor to break the tie seems quite logical. Now why Boeing is being quiet about why MCAS is so critical, and why they never told anyone in the first place, and why the disagree light didn’t work and they didn’t tell anyone, and why they quietly changed the wiring on the stab trim cutouts is beyond me.
As they cannot deliver to other areas that won’t accept it, Boeing should focus on the US.
No sense in dong full up on a plane that just gets put into temp storage.
Start moving all the US deliveries to one location.
See about channeling Ginger Rogers
It is not an easy job, but I am sure Boeing with its back ground, experience will be able to MANAGE it, it requires more efforts, good planning and lot of supervision , however BOEING will do it.
Sure, but a better trick is not having to do something like this in the first place.
Is that experience akin to their experience of building Air Force tankers? Because that’s not been going very smoothly at all. Just sayin’.
As much as I hate the just saying thing its so spot on.
Yea I figure Boeing will manage the MAX return.
But then as Mathew said, good planning would be not to have to in the fist plane (pun intended)
As Boeing has demonstrated on what should be an easy program (767T)
their bench is extremely weak.
So what other need project gets dropped to solve this one?
777X has an issue (maybe only one) and the 797 needs to get launched.
BOEING is on the verge of a precipitous chaos in its multiple issues the deal with the B737 MAX, B777 X, AF Tankers, but on the other hand, their Stock keeps creeping up in very suspicious trend. It would be interesting to learn, with all these unresolved Hiccups who is(are) the main player(s) in this “Contradictio In Adiecto” scenario?
Rising tide lifts all boats… check the value of the Dow Jones stock index its included in. Over a year its gone from 23k to 27K. 5 yr ago it was around 17k.
You will find Boeing is largest proportion of the Dow of any single company and major investors have interest in the Dow Jones to keep rising even if they dont care about Boeing.
They might care if the share price collapses to zero overnight.
If you run a company based on share price rather than on long term profits, it’s risking disaster. The company can’t deliver shareholder value if none of the products are selling profitably.
With over 600 airplanes to deal with, Boeing may be quietly hoping for a phased RTS across the globe. That gives them breathing room to deal with US carriers first, then focus on foreign customers as their regulators give their own RTS blessings. For a myriad of reasons, including politics, I predict the Chinese will be the last to lift their grounding order.
Need to get the plane in tbe air in full test mode flown by Test Pilots.
Note: Max must have new sensors.
Secondly: If its behaviour is suitable for commercial resumption then Certification must be done in stages. U.S. followed by Europe perhaps six montbs later then Asia and Africa & Middle East. Knowledge gained then must be shared or disseminated to follow-up pilots from such Countries.
This is how you establish TRUST within tbe Aviation Community. Shortcuts will lead to complete failure and perhaps scrapping the Max altogether.
My tenure in the 777X program revealed that when engineering is Robust good things follow. There are no shortcuts.
The quickest path would seem to be start with EASA first, then FAA last. The EASA is asking for more changes, and time wasted not doing those in the USA simply means having to do two sets of changes (assuming no one wants a mixed fleet).
Indeed there are no shortcuts. MAX is one big shortcut. Software changes only to address the MAX’s issues is another desperate shortcut that may work in only the USA.
Would that not upset the customers outside of the US? Even if it is the regulators from other countries who are pushing for more change, I am pretty sure that Boeing’s customers in these affected countries would be rather annoyed if Boeing were to go the “easy” route and take care of their American customers first.
I may be wrong but this post seems somewhat premature. I reckon there is some time before Boeing can start the processes. They would be mad to attempt to pre-empt the regulators by prepping aircraft where the updates are not clearly signed off.
Boeing needs to complete the planning and work out the logistics of how they’re going to do it, even if they don’t know exactly 100% what the approved fix is yet.
They’d look pretty stupid if the waited until the day the grounding is lifted before they started this planning work, wouldn’t they?
Would it be reasonable to assume that the delivered MAX should receive priority over undelivered frames?
Of course you are correct, what was trying to get at is that the publicity given to this suggests Boeing thing recertification is a done deal. This may be perceived by some of the regulators as a tad presumptious
I try to imagine Boeing and the FAA (both under investigation) approving 737MAX return to service, while the English, Canadians, Germans, Japanese, Dutch are still completing their analyses of the deadly 737MAX crashes, root causes and required improvements. The FAA would look like a lapdog of Boeing and Congress.
Boeing must have looked at modifications to the hardware,they’re just not going to admit it until all other options are exhausted.
Test aircraft often or always get additional sensor to get flight test data to engineering, so additional alfa probes is pretty simple compared to other flight test instrumentations. The Boeing Chicago business side and SWA is more complicated than complying with EASA demands. The trim wheel forces can be solved with a redundant Mercedes Benz/BMW electronic power steering that have millions of running hours by now…
An additional sensor is of no consequence, the architecture behind the sensors and the appropriate levels of system redundancy is more of an issue. I suspect any integration of the sensors and updating of the current computing power is going to be the difficult part. Hence the desire to avoid all of this if at all possible. I suspect somewhere down the line Boeing is going to have to cave on one or more of the EASA requirements. It constantly surprises me that they are still resistant to actively embracing these changes. A positive response and more proactive approach would have possibly allow EASA to be more relaxed on the recertification and the rectification of the issues. Again hardball is not working for Boeing, when will they learn
Boeing might have to cave to one or more EASA requirements? Without EASA approval no plane can fly to, from or within the EU. The same applies to the requirement for Indian approval. The reality is that nobody trusts the FAA anymore because the FAA publicly admitted they could not be trusted. Government approval has always been necessary because nobody on Earth is stupid enough to trust a private company. Private excellence or private stumblebum is a matter of fact that always has to be determined by testing. donthomson1@hotmail.com
Aviation need similar tranparency as nuclear industri to function even better. ANY deaviation from normal system behavour is reporter and involve also the resech institutions for peer reweivs and to validate the transiant against the calculatations. How can one assess the max issue without knowlege of underlaying aerodynamics and actual behavour against the computer calculations. Obvoius something got wrong early in the desigh process. An very uneducated guess is the new engine location results in earlier separation on the wing behind it and change of lift center as well as the nacsal it self increased lift and drag. Vortex generator could perhaps fix it, but at cost of economy?
If the EASA mandates a fix for the trim wheel force issue (as they say they will), then I can see no way that the MAX could fly before 2021.
All other fixes seem trivial by comparison. There seems to be a collective blindness among aerospace writers to this elephant in the room.
Tim, In a pinch, could Boeing shrink the CRT screens in the cockpit, and put in the old, bigger trim wheel? Wasn’t that the reason they put in a smaller trim wheel in the first place?
Agree, the MAX requires hardware fixes that Boeing is trying to do with software patches.
Heaven’s forbid but what will the outcome be if another MAX must go?
Once Certification of the mod is gained, and that’s the easy bit, how do you convince Mister average flyer that it is really safe. The B787 didn’t cause crashes but everyone knows the MAX did.
I see this as a huge problem. I expect the general public will be giving the MAX a wide berth for a few years yet and will only return after a few crash free years.
To me there are three problems to fix, in order of difficult, least to most difficult.
1. Stabiliser runaway
Relatively easy. Block extreme deflections and reinstate a motor for manual trim
2. Pitch authority
I used the term pitch authority because I’m no longer clear as to whether the ptoblem is stall or it’s elevator authority or both. I will use a separate post to set out my theory.
3. Fail-safe redundancy of sensors
This is by far the most difficult to fix. EASA have said a minium of two of each but that assumes error logic to isolate the physical failure of a sensor. It also means two channels. Three of each is preferred and three channels for that reduces dependency of error logic to isolate failures.
If EASA mandate two of each and two channels and full error logic to isolate failures, Boeing are done. Two years minimum.
What does error logic to isolate failures mean. The FCC did not identify that the AoA was invalid for both the Lion Air crash (20°) and Ethiopian Airlines crash (75°). Equally, the FCC did not identify the altitude was invalid for the Turkish Airlines crzsh (-8 feet, below ground or below water).
The failure to identify and isolate invalid sensor readings caused cascade failure – a meltdown – of the FCC resulting in bedlam on the flight deck.
Yes, MCAS will be turned off if there is a mis-match. But everything can’t be turned off if there is a mis-match. In other words, the entire FCC can’t be shut down if there is a mis-match.
It’s a lot of work even for two of everything and two channels. As I said, two years minimum.
I’ll address pitch authority in a separate post.
Philip, What about the trim wheel lockup? In the ET302 crash, they couldn’t get it to budge, and others in simulators have found the same to be true. If for some reason the one stabilizer trim motor becomes inoperative, in some instances, the pilots won’t be able to have a working mechanical backup. They might try the up and down, reeling in a fish technique, if they have enough time and altitude, but, that’s not always the case.
At the speed the aircraft was travelling nothing short of a large mechanical assist could get that trim wheel moving.
The issue of the trim wheel needs to be addressed, mechanically. To me it is locked into preventing stabiliser runaway. You can disagree.
The other two issues are separate.
I’m not arguing what needs to be done. But why would it have to take 2 years minimum?
Boeing is a very capable company (the research, engineering and production part of the company, not the part that thinks Boeing exists to create shareholder value).
If Boeing would focus it’s resources on these improvements, why wouldn’t they be able to do this in (for instance) 12 months?
I realise people might argue the problem isn’t the lack of engineering capabilities, but how management seems to be in denial about having to improve the MAX beyond a software patch.
Two years is aggressive. They need to replace the CPUs and re-write all of the software to incorporate error logic. And then test it.
That’s why Boeing are saying that if there is a mis-match switch it off. That’s easy. Isolating the reason for the mis-match and acting appropriately isn’t.
It’s the acting appropriately part that is difficult. It’s the reason why all Airbus airplanes are aerodynamically stable. If in doubt let the pilots fly it. Afterall, it’s stable.
Two years is aggressive. Would be a lot better to make the blooming thing aerodynamically stable with hardware changes.
I do get told that my bias is toward Airbus. So may I add
If Airbus relied on software for stability then by now they would have buried 10,000s of people because of problems in their software. Airbus do not rely on software for aerodynamic stability. So if something goes wrong, the pilots fly the airplane. They can fly it because it is mechanically aerodynamically stable.
I break out into a cold sweat at the suggestion that software must be used to maintain stability in a commercial airplane. It really is difficult. Very, very difficult.
Hello Philip,
sorry, but I have to disagree with you. Using software to maintain stability is not difficult but unacceptable for an airliner.
I once flew a single-seater glider that had a reduced stability. I remember perfectly well how I did break out into a cold sweat on my first flight. (It was real fun to fly once you got the knack of it, but if it would have been a twin-seater I would never have dared taking a passenger on board, and certainly not 100+).
This is the reason why EASA demands flight tests of the MAX with MCAS switched off. A test the MAX will not pass without improving the aerodynamics.
It might be possible to achieve an acceptable flight characteristics with “only” increasing the size of the elevator and with a new speed trim system, probably including a new CPU. This would still leave us with the problem that the COL shifts dramatically with the AOA due to the position of the engines. Improving stability might therefor require a shift of the COG forward to achieve a higher downforce on the stabilizer, which will of course cost some efficiency.
This may be my English and your German.
I think it’s unacceptable to use software to maintain stability for a commercial airplane. I thought I was saying that. Are you agreeing or diagreeing.
Modern military airplanes do use software to maintain stability. But then the pilots do have ejection seats. It was for that reason I used the words very, very difficult.
With regard to military airplanes the control surfaces are high speed and high precision. Words not associated with a trim stabiliser on a commercial airplane.
Anyway, it’s unacceptable to me to use software to maintain stability on a commercial airplane. I do break out into a cold sweat at the though.
They need to fix pitch authority with an aerodynamic.
But they still need to fix the FCC. One of each and no error logic to isolate failures. That also means I break out into a cold sweat. Two of each and full error logic to isolate failures is a minimum.
Looking at my words, I think it’s my English and not your German. My original post was far better worded. I hope this post is better worded.
🙂
I”m reading between the lines here .. I think Gundolf is disagreeing only in terms of how easy or difficult it is to use software to augment aircraft stability. Some strange military aircraft (F117 and the B2 bomber come to mind) without software would need an ejection seat rather quickly. In terms of using software in commercial aviation for aircraft stability, I think both of you are in agreement. It may be doable, but, not advisable.
FAA chief Steve Dickson will assess 737 MAX status in a trip to Seattle this week.
Apparently “he intends to perform test runs on a MAX flight simulator while on the trip.”
https://www.seattletimes.com/business/faa-chief-will-assess-737-max-status-in-trip-to-seattle-this-week/
If he’d fly on the MAX during the EASA test flights at high angle of attack, and windup turns with MCAS turned off, that would help restore some confidence I think.
I hope he’s already blocked out time in his diary to personally observe the EASA flight tests aboard N7201S.
https://uk.flightaware.com/live/flight/N7201S
An interesting article blaming lack of pilot skill
https://www.independent.co.uk/travel/news-and-advice/boeing-737-max-crash-aircraft-stall-grounded-pilots-blamed-a9111646.html
William, that is a brief synopsis of a recent New York Times Magazine article. Or in my opinion a hatchet job that Boeing’s lawyers are probably wishing they had wrote. A very good rebuttal to the article is this…
https://www.moonofalabama.org/2019/09/14000-words-of-blame-the-pilots-that-whitewash-boeing-of-737-max-failure.html
William, Richard
The most interesting part of the article in The Independent/New York Times is that the ‘pilot’ claimed that he had recovered from 4 trim stabiliser runaway events in his lifetime, and indeed, appears to take the view that they are common or at least fairly.
If this pilot is right, it is no wonder EASA is having a bit of a panic. Manual trim is now manual trim, no power assistence. The Yo Yo manuever is required and at least 8,000 ft is required to recover. Even then 1 out of 3 pilots couldn’t recover. These were US pilots of huge experience.
But, I was under the impression that trim stabiliser runaway was extremely rare. Can anybody corroborate this ‘pilot’s’ view that they are fairly common and therefore thousands upon thousands of pilots have recovered from them.
This kind of politically motivated article always shoots itself in the foot with the writer coming across as some kind of super human genius with god like skills.
I also thought that stab trim runaway is something very, very uncommon – but this press release shows otherwise. This danger is a real thing.
Good work Boeing, keep blaming non US pilots. FAA soon will allow not-even-half-fixed MAX to fly again in US and will see how super they are.
stab trim runaway occurrences.. it looks like they happen about once a month ..
https://www.satcom.guru/2019/05/737-pitch-trim-incidents.html
Richard:
I minor trim incident isn’t a major one. The issue of trim is always there. The chief reason is fuel burn off.
We come to the numbers and we always come to the numbers. Stabiliser AND deflection of 0.6/0.6/0.6° became 2.5/2.5/.2.5° with regard to MCAS.
Minor trim is 1/10th°. It’s a very minor movement of the trim the stabiliser to address fuel burn. Should anyone expect more than 5/10th° in total during a flight. No
The numbers for MCAS are too high. A movement of 0.6 is too high never mind a movement of 2.5 and so on.
The trim stabilisers moves in 1/10th° during flight not in 6/10ths° or higher numbers.
Will a normal trim stabiliser move more than a total of 6/10ths° during the entire flight. Unlikely.
The numbers are just to big
This is my theory on pitch authority.
Background:
The leading edge of a stabiliser goes up to generate lift to push the nose down (AND). The leading edge of a stabiliser goes down to push the nose up (ANU).
The trailing edge of an elevator goes down to generate lift to push the nose down and goes up to push the nose up.
This then comes to dynamic pressure. I think 250 knots and above will provide the necessary dynamic pressure, but it could be 200 knots and above. Below it, the theory isn’t relevant, which is why MCAS isn’t active with the flaps down.
What we know with regard to the two 737 MAX crashes:
The stabiliser start point is 2.5°. MCAS added 2.5° over 10 seconds. Total 5°. MCAS waited 5 seconds and then added another 2.5° over 10 seconds. Total 7.5°. They are all AND deflections.
The elevators were less responsive at 5° and became inoperable at 7.5°.
The theory:
So lets neutralise the stabiliser to 0° but with an airplane standard AoA of 3°. Add 2.5° to the AoA of the airplane (5.5°) and then another 2.5° to the AoA of the airplane (8°).
Those two movements of the airplane AoA cause an equivalent movement of the stabiliser relative to the airflow, from 0° to 2.5° and then to 5°. But it actually starts at 2.5° so the equivalent is 7.5°. An equivalent stabiliser deflection of 7.5° makes the elevators inoperable.
Why is there an equivalent movement of the stabiliser relative to the airflow? As the airplane rotates relative to the airflow the stabiliser rotates with it.
So an airplane AoA of 8° makes the elevators inoperable for the stabilisers are at the equivalent of 7.5°.
Then comes the lift generated by the engine nacelles . There nothing to stop it except the stabiliser once the AoA of the airplane reaches 8°. So without the stabiliser, the nose keeps going up. The wing stalls at 13-15°.
This comes to the crushing action of MCAS. Remember at a late point in development the numbers were increased by a factor of four. Specifically a 0.6° standard setting of the stabiliser became 2.5° and MCAS increments went from 0.6° to 2.5°.
But the stabiliser is a tortoise. I suggest some watch videos of stabilisers moving. They are all the same. It’s like watching paint dry. Elevators are hares. They move quickly provided they are operable.
So a stabiliser can’t be used to do fine adjustments. It doesn’t respond quick enough. Hence the crushing 2.5°, 10 second burst of MCAS.
Mitigation
It’s not easy or common for an airplane to have an AoA of 8° at 200 knots and even less likely at 250 knots. So please take that into account.
EASA
But the elevators are less responsive even at 5°, an airplane AoA of 5.5°. This is highly likely in a high speed nose up turn. It’s only 2.5° above standard AoA of 3°.
EASA have asked for high speed nose up turns to be demonstrated.
Theory or fact:
It’s theory. Shoot it down.
Philip, I don’t have an aerodynamics background. But, at some point, I would think the stabilizer would stall itself? I’m thinking it moves more than the wing or am I wrong? Would the wing stall before or after the stabilizer? If or when it did, then the plane would pitch down in the same direction? Maybe the wing always stalls first, because they limit the stabilizer, so that it will never stall in the designed limits, unless in ice etc?
https://www.boldmethod.com/blog/learn-to-fly/maneuvers/recovering-from-a-tailplane-stall/
I’ll let folks more expert in aerodynamics than I respond. (that means practically anyone)
Good.
I didn’t completely set it out. I wanted people to think.
Way back I was told I didn’t understand AoA. I replied that there is not a single AoA. Parts of a body may have a different AoA. But equally parts of a body may have a different stall margin.
So yes the stabiliser may have a different AoA but it may have a different stall margin.
But to what? Everything is relative. What is the reference point? Well it’s the wing.
This comes to airplane design. Other control surfaces are designed to stall – become inoperative – after the wing not before the wing. Unless the designers have lost their minds.
In this case it not the stabiliser. It’s the elevators. The elevators are stalling – they become inoperative – well before the wing stalls.
To address that, Boeing have used the stabiliser. It’s still operative even though the elevators are not operative. But it’s a tortoise not a hare. It’s very, very slow. So it’s using forces that are crushing.
So to answer your question. The elevators stall at an AoA far less than the wing stall AoA. But the stabiliser have not stalled. So MCAS uses the stabilisers.
But to return to airplane design. No control surface should stall before the wing stalls. The wing is the reference point. That means the stabiliser, the elevators, the ailerons, the flaps and anything else you want to add (canards). Nothing should stall before the wing.
The fact is the elevators do stall before the wing. My numbers suggest an overall AoA of ~8° but at high speed, 250 knots and above, but perhaps less. Hence the switch to the stabiliser. The tortoise.
I can’t see EASA agreeing to this. The PDF is diplomatic but insightive. It gave no ground at all. Nor should it. Boeing need to explain.
The world isn’t daft. The world isn’t stupid.
The shortest answer I can give.
The elevators stall at a much small AoA to the wing. But the stabiliser hasn’t stalled. So MCAS uses the stabiliser to maintain pitch authority. The problem. It’s a tortoise
To give the numbers in short.
The elevators begin to lose their authority at 5.5° AoA and completely lose their authority their authority at 8° AoA.
Reason.
If AND stabiliser deflections can cause the elevators to lose their authority then the airplane AoA can do the same.
Consequence.
Boeing have no other option than to use the stabiliser to maintain pitch authority.
Philip, This article, in a British Aviation magazine, written by an experienced pilot lays out almost all of the 737-MAX faults we’ve been discussing here (except for the trim wheel size change in the NG and MAX). Long article, but, describes the history of the small elevator inherited from the 707 etc. His analysis and conclusions about Boeing’s 737-MAX are in line with ours. If retired pilots are discussing the problems and fixes in aviation journals, why isn’t Boeing paying attention? Boeing has a new plane (their best seller) grounded for almost a year now and it’s not dawning on them that maybe they should fix it.
https://www.pilotweb.aero/features/737-max-scandal-analysis-1-6127413
Yes, there is a lot of information. Will take time to sink in.
Anyway EASA are going to test it. They have demanded to know pitch authority. So the theories are going to either be rebuked or they are going to become fact.
I do prefer fact over theory.
But thanks for the info. Still taking it in. It always needs to be remembered that any control surface can stall not just the wing. Good design says the wing is the reference. So other surfaces don’t stall before the wing.
It does appear that the elevators are stalling at moderate AoA. Hence the use of the stabiliser. But it does need to be proven.
EASA want to know.
Thanks. Still taking it in.
Philip,
Some worthwhile quotes from the https://www.pilotweb.aero/features/737-max-scandal-analysis-1-6127413 article
===========================
Thus they retained 707-style small elevators, coupled with a much bigger horizontal ‘stabilizer’ (tailplane) driven by a powerful electrical motor with low-geared manual handwheel backups either side of the centre console. The vital thing to understand here is that, because of this, it is physically impossible to overcome the stabilizer’s effect with the elevators (and doubly so with unserviceable hydraulics).
============================
Once the bank had been applied and a steep turn started, it was necessary to push forward on the yoke to prevent the turn tightening and the G-force increasing, after which the aeroplane would then pitch up into the stall unless the pilots input a lot of forward control column movement. These characteristics are clearly not acceptable in a civil airliner, although both Spitfires and P-51 Mustangs plus several types of homebuilt kits exhibit them.
Now, the proper solution to an aerodynamic problem like this is to increase horizontal tail volume. Extending the rear fuselage would not be an option although it would give the tail more leverage, because it would move the centre of gravity aft, which also reduces pitch stability. A tailplane with increased span is the best answer, but of course this would require major structural calculation and strengthening plus re-certification including a lot of test flying. Also it would increase the drag.
===============================
Boeing’s solution was slightly different in each model. Some incorporated a feed to the autopilot’s low-speed stabilizer trimmer to lower the aeroplane’s nose as the airspeed decreased. The early Jumbo’s was activated by the Angle of Attack (AoA) sensors via the stick shaker, so that the shake and push happened simultaneously. Similarly, the 767’s leading edge slats run to fully extended when the stick shakers fire and some 767s have stick nudgers.
To counter the 737 MAX’s pitch instability, Boeing’s designers apparently eschewed a proper aerodynamic or mechanical solution, electing instead to fit an electronic input to the powerful electric stabilizer trim motor, so that it runs for up to ten seconds and pitches the nose down when a pre-determined AoA is reached.
================================
Boeing doesn’t seem to have a Plan B .. they are laser focused on a software patch. If the regulators don’t buy off, and/or the flying public don’t trust a software fix, then it’s literally back to the drawing board for them.
Richard:
Again thanks. I read it twice and still need to take it in.
The words “physically impossbile to overcome the stabilizer’s effect with elevators” are telling but mind boggling.
Please remember that Boeing have publically stated that the stabiliser will no longer be allowed to overpower the elevators. I think the number is 1.5g, if my memory serves me correctly. The elevators will always be allowed to impose a force of at least 1.5g.
So this means they are retreating from 2.5/2.5/2.5° stabiliser positions. Will it go back to 0.6/0.6/0.6° stabiliser positions. Don’t know. But the 0.6…° stabiliser positions didn’t work which is why they wen’t to 2.5…° stabiliser positions.
A bigger stabiliser will work. The elevators should also be resized. But a bigger stabiliser will allow the 0.6…° positions to be returned to. The elevators will then not be overpowered.
The force balance isn’t there. Go one way – reduce stabiliser deflections – causes the AoA to increase which causes the elevator to be inoperable. Go the other way – use severe stabiliser deflections – also causes the elevators to become inoperable. Either way the elevators become inoperable at relatively modest AoA.
The question is can the airplane survive without the elevators? In other words is the stabiliser good enough to maintain pitch authority. It’s very slow.
So yes, Boeing are saying they can develop a software fix to maintain pitch authority using the stabilisers when the elevators don’t have authority.
Will EASA buy it. Don’t know.
But, where’s the fail-safe redundancy in the FCC? The stabiliser is a primary control system. It needs to have fail-safe redundancy.
New stabiliser, new elevators for me.
Philip, There was almost a crash in a 737-800 a few years ago when the elevator froze because of ice. They were very close to a full stall.
http://aerossurance.com/safety-management/de-iced-drama/
(maybe this is one reason they redid the tail cone on the 737-MAX?)
Or maybe this is one reason Boeing is a bit sensitive about getting near a stall?
The elevator may not have enough authority, so they rope in the stabilizer for help, rather than increase the size of the elevator.
Philip, Another 737 on approach with pitch problems because of the small elevator on the 737. Again, a close to stall or actual stall.
==================================
The trimmed position of the stabiliser, combined with the selection of maximum thrust, overwhelmed the available elevator authority.
==================================
https://www.gov.uk/aaib-reports/aar-3-2009-boeing-737-3q8-g-thof-23-september-2007
==============
“Once the bank had been applied and a steep turn started, it was necessary to push forward on the yoke to prevent the turn tightening and the G-force increasing, after which the aeroplane would then pitch up into the stall unless the pilots input a lot of forward control column movement. These characteristics are clearly not acceptable in a civil airliner,…”
I guess this comment should once and for all settle our discussion about the “stability” of the MAX. This also means that the MAX stands no chance to pass the evaluation of the EASA with MCAS switched off.
“The 737 was originally a low-cost, low-risk, low-development-investment project, a simple and cheap 100-seat airliner produced at the same time as this huge corporation had bet its future existence on building not only the revolutionary new, giant, long-range 747 but the enormous production facilities needed to assemble it.”
It is then explained how with every next version patches were developed to fix the difficult aerodynamics that the 737 plagued from the very beginning. But with the last version, Boeing clearly went one step too far.
“I don’t think that merely tweaking the MCAS software is going to solve the underlying problem, although it might reduce the number of fatalities. It will merely be yet another sticking plaster on a pre-existing sticking plaster.”
“This whole issue is tawdry, and completely atypical of the Boeing Company that I have respected for fifty years and more.”
Which is probably how too many people here feel. This is not bashing a great company, but frustration about the path this company has chosen.
Great comments Gundolf
But the words quoted by Richard mean that pitch authority isn’t there. If it was there it wouldn’t be doing it in the first place. Pitch authority means the elevators.
A steep bank means 5-7° AoA. Everything is relative; It’s not a combat airplane we are talking. So the issue starts well before stall and then moves into the stall area of the envelope.
So pitch authority provided by the elevators isn’t there. The only other option is the stabiliser. So MCAS uses the stabiliser. But it’s slow. So the use of the stabiliser must be crushing.
Remember they still won’t allow MCAS to be switched off be the pilots. So the behaviour must be severe.
But MCAS is to switch itself off if there is an AoA mis-match. In which case the pilots are on their own. Hence, EASA asking about AoA integrity.
I really don’t think EASA are going to allow the stabiliser to be used to control steep banked turns. Especially when there is no fail-safe redundancy.
Remember the word ‘steep’ is relative; it’s not a combat airplane
The BA captain is perfectly right. Eventually the stabilizer and elevator needed to grow as the Aircraft and its engines grew over the generations not to be dependent on software functioning perfectly to be safe (like on a supersonic fighter jet with all moving elevator/stabiliser). Even with 2-3 alfa probes reading right its results can be computed wrong and here we go again…
If the FAA recertifies the MAX and EASA doesn’t we can assume the same thinking will apply to future US civil aircraft. FAA certification of the 777-X would be worthless. Not a single US customer. BA might need to take a leaf out of RRs playbook and have EASA as the lead.
PS bad time to talk about tarrifs.
Very interesting fact. Maybe no one in US trust that 777x will be an aircraft with a future.
Wow – now the comments here have moved from “the 737MAX is an unfixable airplane; it will be scrapped and Boeing will have to file Chapter 11 to reorganize” to “non-US certification agencies will refuse to certify the 777X because reasons Boeing corruption reasons”, an action for which there would be no justifiable reason or precedent and which would lead to a massive international regulatory/trade war, the dissolution of Boeing, and a probably global economic recession if not depression.
To paraphrase Mark Twain, “There is something fascinating about [aerospace industry blogs]. One gets such wholesale returns of conjecture out of such a trifling investment of fact.”
@sPh
Well, comments here are moving this or that way
– some speculates that MAX will be back to the sky even tomorrow justvwith a software patch,
– and some speculates that MAX is so flawed that will never should be returned to service.
But behind99% of the comments there are arguments to support this or that tesis. What are yours? (sharp language I don’t recognise as an argument)
Wasn’t thinking quite so extreme. RR certify their engines in Germany, for BA to move certification to EASA probably isn’t impossble. The point is that it might make comercial sense, given the location of the customers is outaide the US.
The same RR that can’t make a safe engine and that is certified by EASA. This site has turn to a Boeing bashing site by Airbus fans . It is clear from most of the post that there are so many people here who are not in aviation industry or professions.
@Daveo
I think you are forgetting that RR engines have some premature wear of some parts at this is addressed in many ADs by inspections, earlier parts replacement etc.
MAX was a clear and present danger from the 0 second in the air and impossible to contain.
I hope you see difference.
I hope that you also will see that a home regulator for B787 is FAA not EASA, and in FAA hands is a lead, so why you won’t criticise FAA instead?
I see really 99% of comments as really valid, I do not see why you call them “bashing Boeing”. Because people are pointing out Boeing obvious and hidden from public and regulators flaws, and Boeing unwillingness to address them all?
@Daveo
RR are not having much fun with the T1000 but you could argue that the GenX is not exactly problem free either. You are the one who is partisan sir, the posters are from a wide range of opinion but unfortunately the MAX debacle does not lend much scope for Boeing supporters.
I am the first to support the great Boeing products, the MAX however has been a self inflicted wound by Boeing from beginning to end. If you think otherwise please let’s talk about it. Don’t shoot the messenger.
This. As poster Revelation observed on OOTOADS [1], some time in the next month Boeing is going to finish redesign work and testing on the 737MAX and turn in their paperwork to the US FAA, at which point the FAA will execute the review process and schedule test flights. When that day comes there is going to be a lot of cognitive dissonance on the world’s aviation boards amongst those who have been advancing the MAX-is-doomed argument and engaging in redesign-by-blog-comment of the work of the world’s single-aisle aircraft manufacturers.
[1] On Of The Other Aviation Discussion Sites
@sPh
You assume that a software patch to MCAS will be enough to bring MAX back to the sky world wide.
Thats not how its done – ‘turn in their paperwork’ It isnt a college exam
This is what has been really going on and Boeing has been stonewalling
“In August, Boeing met with officials from the F.A.A. and other global aviation agencies to brief them on its efforts to complete fixes on the Max. Regulators asked detailed questions about adjustments to the Max’s flight control computers, which the Boeing representatives there were not prepared to answer.
Instead, the company representatives began to display a PowerPoint presentation on their efforts,..”
https://www.nytimes.com/2019/09/15/business/boeing-safety-737-max.html
Well, yes, in a regulated industry that is how it is done: the entity receives an adverse inspection report or a directive to remove one of its products from the market; it works on a solution to the problem; assembles the paperwork required to demonstrate compliance with the law and associated regulations; and turns that in to the regulatory agency for review and approval under the policies governing such processes. It happens every day in nuclear, pharma, and aerospace.
The idea that there is going to be some sort of dramatic confrontation between enraged regulators and an arrogant and non-responsive Boeing Corporation, followed by a ritualistic public flogging of Boeing, is the childish idea that has been driving comments on this issue for the last 2-3 months.
This whole Boeing 737-MAX failure and the way they are hiding most every piece of information doesn’t fill one with trust in Boeing. Just the opposite. Being open and above reproach isn’t being demonstrated by their actions. Some things I understand should be done in private. But, the extent to which Boeing is not being forthcoming is troubling. That’s what started this whole mess. Boeing not telling airlines, pilots and regulators about MCAS. It’s no wonder that EASA and the rest of the world want to see for themselves. It’s no wonder Boeing and the FAA have lost credibility. A recent Fortune article speaks to the problem in bringing back the MAX.
https://fortune.com/2019/09/06/boeing-wants-to-bring-back-its-737-max-this-year-but-a-spat-between-regulators-could-thwart-it/
“The idea that there is going to be some sort of dramatic confrontation between enraged regulators and an arrogant and non-responsive Boeing Corporation, followed by a ritualistic public flogging of Boeing, is the childish idea that has been driving comments on this issue for the last 2-3 months.”
This is partially correct and while your colourfully descriptive narrative does evoke a certain image, the fact of the matter is, regulators from certain countries, who all acted quicker than the FAA earlier this year, have publicly indicated it is far from certain that a lifting of the MAX grounding by the FAA will be automatically mirrored in these other countries.
It is also true that most have not said it will necessarily be that way. They are all evaluating and have only made one thing clear, they would like to have their own look at what Boeing is offering and what the FAA is approving, and more importantly why it is doing so.
Yes, some people are engaged in prophesizing the doom of the 737 program and the eventual demise of Boeing itself, leading to the downfall of the US and society as a whole BUT there are many looking at this objectively, or at least as objectively as they can, and they see things that don’t look good.
• Boeing has now two commercial programs in a row in which their aircraft have been grounded for safety reasons.
• Owning up to their problems is not a strong suit of Boeing.
• It seems to be well documented that Boeing managers have used the new FAA certification structure to exert undue pressure on the FAA representatives working for Boeing (as if the fact that they are working for Boeing itself in the first place is not an eye opener, but now they are no longer “protected” by the FAA and are completely beholden to Boeing under this new scam, er scheme.)
While you might believe that some are overstating the case here, something with which I agree, there is still enough information here that is disturbing.
@Aero Ninja
You have very much echoed my viewpoint on the matter. In essence ‘much ado about something’
What Revelation, and you yourself, seem to overlook, is the response of the rest of the worlds regulatory agencies.
If you have been missing the news, some are strongly indicating they won’t automatically accept the FAA’s judgment.
Obviously what is happening in the background is unknown to all of us.
The direction of some comments, which reproach people for their negativity, shows how right vs. left arguments and discourse tend to pan out in the US: ideology vs. knowledge — as if the two sides are the same — with all of its tragic consequences.
Livemint is reporting that India will do their own review before returning MAX to service, but won’t even begin to work on it until FAA lift the grounding. Simultanious return to service is out the window. Will China follow suite? Also reporting that they’ll probably require sim training.
Much tedium in assembly and maintenance work, this isn;’t a lot different.
As for ‘early in 4th quarter, that’s a month away – perhaps optimistic for even FAA blessing.
As to AOA vanes, I ask what the DC-10 had – it flew out of European countries. Had some kind of dual-dual avionics IIRC, not reliable.
AA had a clever placard on the main instrument panel, it had a circular piece with a wedge shaped opening in it, a piece behind was rotated to say Land 1, Land 2, Land 3 for the autoland capability of the moment, then re-tightened. Technicians could quickly downgrade if there was a failure, and dispatch after testing with a replacement LRU, later upgrading status if removed LRU checked faulty in the shop and the additional aircraft testing for the higher category was done.
The A320N has problems of its own with CG. Lufthansa is blocking off the last row in economy.
http://c.newsnow.co.uk/A/1000255936?-2567:9097
And the authorities has warned British Airways that the rear of the plane could be to heavy in the back due to their 29″ seat pitch on the 320N.
http://c.newsnow.co.uk/A/1000602238?-12705:4040
Lets see how Airbus handles this, maybe the 320Plus with a larger stretch in front of the wing than behind? The same could apply to an A321Plus.
Indeed the CG range on the 32xneo has been restricted from the original specification. Basically airlines need to put less weight in the back of the aircraft. Blocking off seats is one way to do this.
But bbecause Airbus is full FBW the fix will not require any physical changes, the flight rules will be changed to address the circumstances where it is an issue (aggressive pitch up maneuver close to landing). The fix is due late 2020.
AD has been issued at Airbus request to be careful if center of gravity is to the aft.
Just saw Steve Dickson on Youtube showing that he was in Boeing’s pocket. He did pretty well until the last minute or so of his segment and then he seemed to make a distinction between the quality of US pilots and those around the world.
This is clearly buying into the Boeing narrative of the crashes being at least partly the fault of the pilots when I understand that this is not the case. That is rather worrying to me and suggests that he is working from the Boeing playbook.
https://www.bing.com/videos/search?q=boeing+max+news&view=detail&mid=409D16C539C12EE4D434409D16C539C12EE4D434&FORM=VIRE
While I’m skeptical of the FAA/Boeing relationship, especially since the change where Designated FAA Representatives report to Boeing directly, rather than the FAA, I’m glad that the head of the FAA is a former Airline Pilot.
“Steve Dickson, flew in line operations as an A320 captain, and previously flew the B727, B737, B757, and B767 during his career”. I hope his simulator flight is filmed and will be shown to the public. If they did that, every 737 pilot would be watching his every action in the simulator. Since there is currently only one simulator set up for
the new MCAS, I’m sure practically every 737 pilot would want to watch his reactions. As a matter of fact, it would
be great if Boeing filmed some of their test pilots in the simulator, and/or during a test flight.
I think live streaming test pilots flying a physical MAX aircraft near the limits (high AOA, and windup turns) with MCAS turned off would help to convince the public.
Sorry but simulators don’t cut it for me at the moment. We’ve only recently found out that the simulators didn’t accurately represent the forces present when trying to use manual trim. How would anyone know that the simulator really did represent a flying aircraft ?
There will always be conspiracy theories out there, but they can be minimised by transparently showing the reality.
If the aircraft is as BA are stating it is, there should be no problem performing the flights as suggested by EASA, and live streaming them.
The test pilots would have an advantage, they would know exactly what was about to happen, and when. They would also have made sure that they had planned exactly how they were going to react, and they’d have plenty of altitude.
They’d also be Boeing’s best pilots, so there would be no question of too few hours, or not completing checklists fully while mayhem broke out in the cockpit.
My 2 cents worth… Boeing be open, do all the testing required by EASA, and do it publicly.
Boeing’s internal safety review is beginning to leak out
https://www.nytimes.com/2019/09/15/business/boeing-safety-737-max.html
They don’t really mention any change of the ODA reporting lines of authority for the Designated FAA Representatives. I was hoping they’d recommend changing their reporting directly back to the FAA rather than through Boeing management, as it was in the past. That is rather a glaring omission, if it’s not in the final report. If the FAA Rep’s still report through Boeing management, then nothing really has changed. And you have Boeing approving Boeing, without the FAA knowing the details. As in the last minute MCAS changes.
“Boeing Chairman Muilenburg is asked to testify before Congress next month”
https://www.seattletimes.com/business/boeing-aerospace/boeing-chairman-muilenburg-is-asked-to-testify-before-congress-next-month/
https://newrepublic.com/article/154944/boeing-737-max-investigation-indonesia-lion-air-ethiopian-airlines-managerial-revolution
Nothing really new here, but nevertheless revealing.
–
–
Steve, Thanks for the link. A lot of information in one place, and a good overview of the management involvement in the 737-MAX problems. Maybe they should rename the plane MD-13, to point out who’s truly making the engineering decisions at Boeing.
It could be argued that the engineering decisions are made in New York, not in Chicago. Let alone in Seattle.
Indonesian final report may be coming out in November.
https://www.wsj.com/articles/indonesia-to-fault-737-max-design-u-s-oversight-in-lion-air-crash-report-11569185664
Not much mention is made about informing operators or pilots of how software controls the plane. I think that should be a mandatory FAA requirement on all civil aircraft made. How the dang thing works. I would think pilots may be interested in that type of information.