Agreed. This may become more common since as far as I understand aviation authorities around the world used to trust the FAA. Now they don’t and are doing their own due diligence.
My understanding is that the certification work by FAA was simply trusted by EASA, and it was just carried over.
The FAA in turn had been systematically delegating parts of the certification back to the manufacturers themselves, and obviously have not provided enough oversight.
After the crashes the EASA have obviously determined they need to redo the verification work themselves.
Does the FAA trust other countries agencies when certifying aircraft? Does the EASA do their own extensive testing and certification on Airbus planes, or Canada for Bombardaria, along with the FAA? Or has the US turned into some type of de-facto authority over all airplane certification (in they way the US FCC has for space satellite launches and tracking?)
There are generally agreements between the various countries’ aviation certification authorities so that a system or aircraft is certified in the country of its design/manufacture and it is accepted in other countries. The harmonization of the rules between countries is always fun.
For example, I worked on a program where we certified the glass cockpit upgrade for the US Navy trainer, T-6A to T-6B with Transport Canada, the aircraft with the new avionics was certified by the FAA, and the whole system was then accepted by the US Navy. Satisfying all 3 stakeholders at the same time often proved difficult.
EASA trusted the FAA to do their job and actually check the plane before certifying it. The FAA instead gladly outsourced the certification to...
... Boeing.
Which ultimately leads to the loss of reputation for the FAA, which is why EASA is now checking the plane themselves and finding numerous faults with it.
It's like University A would tomorrow get rid of all teaching assistants because it's cheaper that way and just have students self-grade their exams. Everyone will hence have only A+ and everyone is happy. Until finally a lot of really bad University A students will leave the job market unimpressed and thus hurting the reputation of University (FA)A.
It seems like the sane thing to do is to scrape all these 737-MAX planes currently grounded. They should have all their parts recycled/reused into a completely new airplane and the 737 should be retired.
Of course that's not going to happen. There is simply way too much money involved and way too many interests to allow Boeing to take that kind of hit.
It seems like the airline industry is surviving without this substantial number of planes in their fleet. Have prices surged for the old 737-MAX routes? Have companies taken out more debt to put in orders for Airbus and Bombardier replacements, or are they confident the existing stock will return this year?
The 737 did survive their rudder issue several decades ago. Maybe this new generation of 737 will survive this? I'm sure there are a number of people who will avoid booking flights on these jets if they can though, at least for several months or a year.
The airline industry wanted another 737 far more than Boeing wanted to make one. Retiring the 737 puts Southwest and Ryanair’s business model at risk. It’s far more than Boeing at fault here, and airlines are keeping their mouths shut because they’re more than happy to let Boeing take the heat for this.
Why do you think this was a best-selling plane for Boeing? Who's buying it, and why?
The answers to that question and yours are the same: airlines want to decrease operational costs, of which pilot training and specialization is a huge component.
You're blaming those airlines because they wanted to buy boeing's product? Let me rewite that as it comes across...
tempguy9999 happens to fancy a bottle of spirits right now, it is the weekend after all.
tempguy9999 pops down the road to the local offy (short for off-license, brit-english for place that sells booze), and being skint at the moment, I ask for the cheapest thing that will get me sloshed.
Sales bod suggests x. I buy x. I drink x and go to hospital because x contains a big dollop of methanol.
I went to (what I honestly thought was) a reliable supplier that's sold me loads before with perfect satisfaction, and got something dangerous. I did not know it was dangerous, nor was I told it was dangerous. Also, that supplier had a world-class reputation.
I don't accept it's Southwest/Ryanair's fault at all.
It’s as if you demand a bottle of something exactly like, but not quite exactly methanol and end up with methanol. Southwest demanded a 737 that met criteria the airframe absolutely could not accomplish. It’s Boeing’s fault for building it but it’s Southwest’s fault for buying the impossible.
> It’s Boeing’s fault for building it but it’s Southwest’s fault for buying the impossible.
respectively yes, and, can you show me what southwest actually asked for that was so extreme?
edit: actually, I'm not sure. If mcas had worked correctly (including being documented) then 2 planeloads of people might not have been dead, but AIUI it fought the pilots and sadly won.
The answer is to stop calling this a 737. Make it a new airframe subject to new type certification. That frees boeing to adopt comprehensive flight controls rather than this layered protections approach. It also means fully training new crews, the avoidance of which was much of the 737-max selling point.
It won't change the problems of the plane, but it will allow Boeing to actually fix them
The problem with the Max is that Boeing favoured the major airlines that wanted 2010s technology in a 60s airframe. But guess what, that doesn't work, in the same way you can't turn a Thunderbird into a Tesla by "just plugging a new engine".
Not that Boeing probably didn't have a vested interest in not investing in a new airframe and preferred the lowest cost project
Now if they can call the Max the 737-2, cut the legacy crap and work around the longitudinal stability by breaking backwards compatibility (and sell the plane at a discount) they could end up with smaller losses
> The problem with the Max is that Boeing favoured the major airlines that wanted 2010s technology in a 60s airframe. But guess what, that doesn't work, in the same way you can't turn a Thunderbird into a Tesla by "just plugging a new engine".
No, the problem with the plane was that Boeing engineered a crappy solution to a problem they had.
There were 3 major problems that I am aware of.
1) A powerful(flight control wise) automated system that relied on one source of sensor data when multiple are available.
2) The switches that disabled the automated system also disabled all electronic control for the elevator trim, making it much harder for the pilots to recover from an out of trim condition.
3) The normal elevator controls are not enough for the pilot to overcome the out of trim condition so pulling back on the yoke as far as possible would not pitch the plane up enough to regain altitude.
The only way to recover from this type of situation is to momentarily pitch the plane further downwards to take stress off of the elevator trim so the manual controls are easier to operate with your hand. You would have to do that enough times to get the plane back into a stable position, this is not always possible when the plane is already at a low altitude.
They should be able to override the trim via thumb switch and then cut out the trim system once it’s trammed in. Mcas cuts out when the thumb switch is applied.
This is incorrect. Fly-by-Wire makes minimal difference when the basic aerodynamics are flawed and non-compliant. Airframe certifiability is behavior based. You must meet a prescribed set of behaviors, while lacking any prescriptive misbehaviors. The idea is an airframe in it's minimally "assisted" state should demonstrate basic airworthy characteristics.
A plane should be airworthy even if the majority of it's automation has suffered a casualty.
False. The MCAS exists to prevent stick forces from inverting as the nose pitches up towards the stall angle. If the stick forces invert, it becomes easier to continue into a stall angle than to move away from it. Commercial airframes are required to never exhibit this characteristic as a condition of certification.
MCAS was Boeing’s idea of a solution to this; command the stabilizers down to provide counter force against the stick, making it harder for the pilot to pull into the stall than pull away from it at every point.
Even if the 737NG had never existed and the 737MAX as it exists today were for some reason an all new design, it would need the MCAS counter-force to get certified as air worthy no matter how much new training pilots got. It (claims to) solve a fundamental airworthiness requirement; it is not a “737NG emulation feature” as some mistakenly believe.
Those problems started with Boeing wanting to keep 737NG type rating as a selling point.
Keeping the type rating means that they needed to avoid making completely new wings or significant fuselage changes, which would require a new type rating as well.
All of that led to fitting engines in a way that caused a bunch of aerodynamics problems, which led to crappy solutions.
Changing the name means a new type cert. It means new a wider scope of design. It means new flight tests, from scratch. It is a very meaningful action.
Sure, “changing the name” fixes the problem if you also...change the rest of the airframe.
It’s really not maintaining the type certification that’s the problem, it’s the aerodynamics of the airframe. If they’d called it a 797 from the beginning it would still have needed the MCAS to get FAA approval because the insane aerodynamics mean the stick forces don’t obey the regulations for constant increase in forces approaching a stall. The MCAS isn’t there just so it can pretend to be a 737.
So yeah changing the name is only a solution if by changing the name you mean fundamentally changing every aspect of it.
>>> Sure, “changing the name” fixes the problem if you also...change the rest of the airframe.
It’s really not maintaining the type certification that’s the problem, it’s the aerodynamics of the airframe.
I don't think you understand the regulatory regime. Changing the name, creating it as a new airframe, means total top-to-bottom re-certification. That means they can ditch all the legacy equipment and start the control system from scratch. Most of the problems with the max atm are related to systems layered atop that legacy equipment (autopilot, control surfaces etc) that cannot be swapped out without changing the type/name.
Right but the type certification has nothing to do with why it’s designed the way it is. You seem to think they started with “maintain type certification uber alles” as their goal, when it was actually just a happy consequence of their goal, which was “sell airlines an airframe the same size as current 737s, so they can keep using the same height gates and service vehicles as their vast 737 fleets, but make it much more fuel efficient”
The fucking name isn’t the problem. Trying to work fuel efficiency into too small a package and ending up with something with the stall characteristics of a brick is the problem. Creating it as a “new airframe” fixes the problem only by abandoning the problem they set out to solve, which again, wasn’t “keep the name”.
If this had been the 797 from the getgo, but had tried to put those engines on any airframe that stayed that low to the ground for gate compatibility, they have still needed the MCAS because of the aerodynamics of the necessary engine placement.
Remember that the 737 is such a big seller because it has huge usage on regional routes and in smaller countries. It lands at airports where they still wheel up a set of stairs, or one of those double-decker deplaning buses. The height is a big deal for established infrastructure of customers. If it weren’t, they could have redesigned the landing gear to get the necessary engine clearance instead of fucking up the aerodynamics by moving the engines.
The height, and not the name, is the original sin from which every shitty consequence flows.
They sure could make an MCAS-free 797 low to the ground with those engines. There are lots of ways.
The popular way is with a T-tail and podded engines off the sides of the rear of the body. Boeing has produced such an aircraft. https://en.wikipedia.org/wiki/Boeing_717
Another way is with a high-mounted wing. This is popular for military cargo jets, such as the C-5 and C-17.
Putting engines above the wing is an option. Boeing did it for the YC-14, Antonov did it for the An-72, VFW-Fokker did it for the 614, and Honda did it for the Hondajet.
The landing gear could have be made to stick out extra long for the takeoff and landing, but then partially retract for passenger boarding. During passenger boarding, the aircraft could even sit on the engines.
The FAA doesn't care about the name. They can require a type certificate specifically for the 737 MAX series, separate from the 737 NG series.
And a type certification isn't the only way to require additional training. For sure there are meaningful differences between the 757 and 767, despite sharing the same type certification, and pilots do go through that difference training. There are numerous examples of this.
Where Boeing probably wants to be, is in the vicinity of the regulatory distinction between the A320 and A320neo. It seems really unlikely to me that any 737 NG to 737 MAX transition training burden, is going to approach that of 737 NG to A320neo transition training.
The MAX as it is would not exist if they went that way, as they would then have the freedom to say screw it and ditch all the excess baggage of maintaining the 737 type certificate.
No aerospace engineer worth their salt would have designed the MAX as is given the freedom to reconfigure and avoid all the problematic aerodynamics inherent to the design entirely.
As unfortunate as it might be, I feel this situation is the perfect demonstration of the "speed, quality, price; pick 2" conundrum.
They went fast to beat Airbus, cheap as the total cost of the package (plane + training + etc ...) and therefore quality takes a hit.
It happens everywhere but I think we were all under the assumption that surely this industry wouldn't stoop as low.
I've been told a while ago that the engineering of planes involved a fair amount of "duct-tape" (used loosely here) to make all of it work despite the risk involved. I didn't think much of it.
Now I sure have a different take on those words. While growing up plane crashes that happened were rare or their own kind of event(9/11, german pilot suicide, MH370). Therefore people around my age (30) might have bigger faith in planes than one should expect from travelling in hundred of tons of metal, composite materials and fuel going 500+ MPH in the sky.
Yes, provided that the reasons of the actual issue are essentially linked to:
1) delegation from FAA to "Boeing internal"
2) poor communication during the design and/or poor review of the decisions made in earlier stages
3) the deliberate taking of shortcuts (changing the amount of correction the MCAS without documenting it or re-running proper tests/verifications)
4) the use of this or that verbal/lexical workaround to avoid a re-certification of the plane, which essentially ended up in hiding info from the pilots
The problem is not limited to the specific issue, the above are IMHO clear signs of a (deviated) modus operandi from the company (but possibly also from the FAA), the same mis-management may have caused (or may not, but there is no way to know) tens of other potential issues that by sheer luck have not caused any accident to date (or have not yet been noticed because they only happen in corner cases).
Previous (historical) recalls and modifications to Boeing airplanes (often mandated - after an accident - on the basis of NTSB reports) were - AFAICR/AFAIK - mistakes "in good faith", this one seems like the result of a general lowering of the processes.
Airplanes and Aviation systems are safer now than they ever have been - look at the frequency of crashes 1959-1989, and look at them from 1989-2019 - you'll see a sea change in frequency.
You’re not the only one. It’s a fundamentally flawed design that should be scrapped. That people are focusing exclusively on the software is a testament to the power of PR and regulatory capture.
It's not just a matter of strength to operate the trim wheel, which can vary a lot depending on the mistrim forces. It's also fatigue from pulling back on the yoke. And it's also altitude.
That means time is a factor that has to be taken into account. There are configurations where a mistrim flat out cannot happen at a certain altitude or it isn't recoverable in time before hitting the ground, regardless of strength.
Only about a third of new pilots in the US now come from a military background, and it is probably less globally. Commercially trained pilots probably have less stringent physical conditioning and experience.
Female pilots and pilots from ethnic groups of smaller stature also need to be considered.
The FAA First Class Medical requirements don't seem to have any requirements regarding physical strength.
Part of me feels Boeing gets what they deserve but there's also some possibility for nasty competitive foul play if Europeans really decide to turn the screws on Boeing to help bolster Airbus.
>but there's also some possibility for nasty competitive foul play if Europeans really decide to turn the screws on Boeing to help bolster Airbus.
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Then FAA would fight back and everyone loses, for now there is no reason to doubt the issues raised so let's wait until say Europeans raise some bogus reason and then accuse them. though so far FAA and Boeing are the ones with less credibility (since were trying not to ground the MAX even with 2 planes crashed)
> Both the FAA and EASA along with Canada and Brazil
That’s two interesting other countries, presumably chosen because the presence of Bombardier and Embraer mean Canada and Brazil have some experience in certifying planes? Notably missing are Russia and China who also make planes
Notice at the same time, not only the manufacturer, but also the authority CAAC, the China counterpart of FAA, is behaving more and more independently, as the first regulatory agency to ground 737MAX.
Should they though? I feel like that CAAC had the least to lose and the most to gain by grounding the 737 MAX. Them being proactive is really only because of politics.
Is there a point at which it makes more sense for Boeing to cancel the MAX and start over with a new airframe?
Personally I don’t love the idea of flying on one of these at this point, no matter how many tweaks they make. I’m sure many others will feel the same.
At what point is a new airframe the better PR move for all involved?
The PR fail with the 737 MAX might also bankrupt the company if no one wants to fly on them. I know what I would do as CEO facing those two dire futures.
Fly with a different airline? Don't fly at all? Take the train?
I already use sites like seatguru.com to work out the best seats on flights - I guess I'll now be checking to see if it is a boeing plane or not before booking.
Delta, JetBlue, Frontier, Spirit, and Allegiant come to mind. None of the carriers that fly regional jets for American and United have 737s of any sort. If the PR is that bad both Alaska, American, and United are in a much better position to scrap their MAXs than Southwest.
Now if the 787 is grounded or loses ETOPS certification, that'll be a much bigger hit for the big US airlines.
I mean, Boeing’s market cap is ~$95B. If we’re in a fantasy land where Amazon is going to buy that many planes they might as well just buy the whole damn company.
No it doesn't. No reason backed by facts available to the public for decertifying the airplane have arisen.
The worst case scenario (for Boeing), at this point, is the FAA and/or other aviation regulators, decide that the differences require different type certification for the aircraft and therefore mandate a unique type rating by pilots to fly the plane. That would require they be trained about those differences.
Would that not have all the companies that bought the MAX asuming that they would not have to retrain their pilots asking for some $$$ or even cancelling?
I'm not sure I'm parsing this question correctly, but it sounds like a contracts question, and I'm not at all privy to the contract between any airline and Boeing, whether they have any contingency for this.
The actual risk is complex, an airline with more capacity depending on the new model has more risk as they take on new planes and retire old ones, but does the contract reflect that complexity? I have no idea. For all I know, there's generic terms for handling all certification problems that crop up, including airworthiness directives from the FAA that affect A&P's rather than pilots. It might be the two sides split the cost 50/50 for all I know, or maybe they use binding arbitration to keep the airing of dirty laundry as much out of the public view as possible.
There are more than enough reasons to reasonably decertify the aircraft. When you start doing things that "fly-in-the-face" of industry best practice, and begin requiring the most liberal interpretation possible of regulations as written, it's time to start dialing back what you're willing to let slide.
Even with these "minor tweaks" to every fuselage, the airframe can reasonably be assumed to have further problems.
As a for instance, what happens if a dual flameout in flight occurs? Does the Ram Air Turbine make enough power to run the Flight Control Computer and all it's dependencies to ensure the MCAS functionality stays intact until the plane can be safely touched down?
If not, will there be simulator training so pilots are prepared?
There is more than enough publicly available information to be cause for concern.
>As a for instance, what happens if a dual flameout in flight occurs? Does the Ram Air Turbine make enough power to run the Flight Control Computer and all it's dependencies to ensure the MCAS functionality stays intact until the plane can be safely touched down?
Isn't MCAS a solution to address greater nose pitch-up due to stronger thrust vectoring effects from the new engines? In a dual engine flameout where all thrust is lost, doesn't thrust vectoring cease to be an issue?
It's not actually the thrust MCAS counters; that is counterable by elevator alone. MCAS counters extra lift generated by the nacelles shape and position at high Angle of Attack. No thrust is required to reproduce the aerodynamic effects MCAS is intended to counter.
That's why this damn kludge of a system is so concerning. It's an active airworthyness hack to counter a passive aerodynamic characteristic of the airframe.
So if a double flameout occurs, killing all power, and killing the Flight Control Computer due to unreliable voltage being supplied from the Ram Air Turbine, the pilots are stuck flying a glider that'll try to pitch into a stall on them if they aren't careful.
Again, normally wouldn't worry about something like this, but they missed/intentionally left out the single AoA sensor...
So...yeah... I have severe concerns about this design, and the effort put into known, unlikely, but highly severe failures.
> So if a double flameout occurs, killing all power, and killing the Flight Control Computer due to unreliable voltage being supplied from the Ram Air Turbine, the pilots are stuck flying a glider that'll try to pitch into a stall on them if they aren't careful.
Maybe you shouldn't post such strong statements about a technology you know very little about.
First: The 737 does not actually have a RAT.
Second: On types that have a RAT (e.g. the A320) it isn't electrical, it provides hydraulic power to operate the flight controls.
If you need emergency electrical power from a RAT equipped aircraft it will be from an haudraulically driven AC generator through a constant speed drive. It will not have voltage fluctuations, only risk is frequency being off and aircraft systems are designed to deal with that.
It's annoying to have people twist words around, and this isn't the first time you've done this to me on this same subject. There is plenty of public information to be concerned, not least of which are all the dead people. There are no public facts that demonstrate the 737 MAX failed to meet any requirement of FAR 25 without the aid of a computer.
The article you cite doesn't even mention FAR 25. The strongest statement it makes is this:
“to address potentially unacceptable nose-up pitching moment at high angles of attack at high airspeeds,”
For my purposes, that whole statement is rendered useless bullshit by the word "potentially". It's like saying "maybe, maybe not, who is to say?"
That statement in the article implicates the 737 MAX as not conforming specifically with FAR 25.173(c), but does not come right out and say that. Further, no source has said, one way or another, that the FAA permits computers as an aid to certifying airworthiness for designs that without computers would not be certified under FAR 25.
There is not enough public information to decertify the plane. Realize exactly what you're really saying: the airplane should not have been certified airworthy to begin with. You can't really decertify it without, in effect, saying malfeasance has happened. It isn't merely that MCAS wasn't good enough. It's that it should never have been considered appropriate to use software to paper over aerodynamic problems in the first place.
Am I suspicious that's what has happened? Yes. But is my suspicion evidence or a relevant fact that demonstrates it has happened? No. And all we have with articles thus far is speculation and suspicion. Where are the facts that prove this?
There is more than enough information to work backwards from in order to draw a reasonable conclusion just in the public eye. Any attempt to downplay that is disingenuous.
I can't account for what pile of fecal matter will be shoveled on the FAR's to justify the MAX, and to be honest cmurf, I believe it was a post of yours that ended up galvanizing for me that something is incredibly wrong with the MAX. The fact is, regulations in the United States seem to become negotiable after a certain size actor starts coming into play, and like it or not, that's the way it's worked since I've been around to see it.
Seattle Times found documented proof of non-compliant curves.
You might find 'potentially' magically turns something into 'bullshit', but as someone who works in risk management, and is well versed in the physical sciences, "potentially" means that something is likely enough not to be trivially discounted, and requires an effort to remediate. It means "the potential exists; there is no known law or other invariant that reasonably discludes or prevents outcome X from being the case". If there is anything to being an Engineer, you have to admit that the the word "potentially" means something coming from them.
Seattle Times also broke the story on how Boeing regressed switch functionality in order to make sure the Stabilizer Trim cutout procedure lined up with what was already documented, but failed to provide educative material as to why the change, or also ensuring that pilot's who knew they could isolate the autopilot from the trim motor without cutting out their trim switches no longer could.
60 Minutes reported on active attempts to circumvent FAA scrutiny (decision to go with the single sensor input). I won't go as far to put names on actors, but there is more than enough stink of malfeasance that the poor engineering decisions, the motivations behind changing the focus of the company from high quality aircraft design to shareholder value generator, and the actions of current regulators in dragging their feet to deal with the problems that have been uncovered should stoke righteous indignation at the nerve of people who purport themselves to be responsible stewards of the public's safety to be so sheepishly approaching what is one of the biggest demonstrable breaches of the public trust of our time. These are not suspicions. These are not suppositions. This happened. You want to know where the facts are? Grab a pencil, some paper, and a computer, and crack open a few books on aerodynamics, numerical methods, CFD, and simulations. Then, run down as many dimensions as you can. This will act as the foundation for your coming aerodynamics analysis. Read through some white papers. Reason. Look at different plane designs, understand how different trade-offs effect the machine.
Don't feel like becoming an aerodynamicist in all but the job/paycheck? Then you'll have to live with the outputs generated by the media like everybody else, or say screw it, and do your best to understand the science anyway.
You can wait for the lawyers; I've worked through enough to assure myself that if the rest of the world dropped the issue tomorrow, I'd still not put anyone I cared about on those planes on principle, and on the basis of too many unanswered questions. I have no compulsion to do anything to help Boeing's image, and the shots I fire I ensure have sufficient grounding in what is reasonably deduceable from publicly available information to not be a bad faith hindrance. If they want things cleared up. They can put all the information where God and everyone can see it. The concern with the RAT being deduced from the Gimli Glider iincident; where the electronics getting knocked out ended up leaving pilot's with very few automation aids to land the plane. Just because it happened due to a fuel screwup doesn't mean it's outside the realm of possibility of happening from somethi...
Also, the thrust change nose-up moment is not much different to a 737 classic or 737 NG; MCAS is required due to the lifting moment of the engines, which are in front of the center of gravity (thus pulling the nose up when in a positive AoA situation).
You should probably not fly any 737, then, because it's had just as many bad, bad design flaws that killed people. Oh, and it's also the most successful commercial aircraft in history.
I'm not sure the plane loads of passengers killed would agree with your professional opinion of design competence.
Edited to add: the rudder design was "new" to the industry, in that it had a single control surface activated by a single control mechanism with no redundancy (sound familiar?). The rudder control valve in question had been found to malfunction on 747-200's earlier and was replaced in the entire 747 fleet. The 737's were not replaced until after more fatalities.
The point of all this is that there are "incompetence" narratives that can be woven around all major design issues in commercial aircraft. To say "I'll ever fly one" displays a lack of understanding of what makes commercial aviation the safest way to travel, and what the risks actually are.
The point is that the MAX design flaw is so shallow. It uses a single sensor. If the sensor malfunctions during flight, then the software instructs the aircraft to dive into the ground.
No right-minded person would ever design a flight control system like that. It's not merely wrong but wrong in such a basic way, as if designed by a child.
Such a situation reasonably makes people question whether the MAX project was managed by competent individuals, which is obviously a prerequisite for many people to fly in one.
They had the exact same number of crashes, plus one near-crash. Very similar to me. Planes flew with much lower passenger loads in those days so total fatalities can differ.
I don't know what the exact crash rate (i.e., % flights that end in hull loss) was.
It's actually worse that I stated: 2 confirmed fatal crashes, 1 severe malfunction in-flight, 4 fatal crashes that are most likely same cause, and two more in-flight loss of control incidents that are likely same.
It's pretty clear you aren't actually interested in obtaining a balanced view of design flaws in aircraft, rather just trying to win some kind of points.
Some design flaws take time to show up, due to life cycle aging. Most of the rudder issues were in 737-300's, which began full production in the mid-1980s. There isn't just a single "737" model, even for the same 737-XXX series.
You can do your own research from here on out. If 6 fatal crashes plus non-fatal incidents due to the same design flaw don't persuade you then perhaps you are not persuadable.
The basic fact, that there are plenty of previous cases of serious design flaws in aircraft that became quite safe, is sound, whether you choose to accept that or not.
> Personally I don’t love the idea of flying on one of these at this point, no matter how many tweaks they make. I’m sure many others will feel the same.
I would rather fly on one of these once they're back in the air.
The alternative to found and fixed issues is not a lack of issues.
The amount of scrutiny this plane is going to be under is insane. I think once it is back in the air we can rest assured the kinks have been worked out.
Deep scrutiny only has moderate impact when it comes to finding and fixing bugs.
An issue can be extremely difficult to identify and understand in the first place. Assuming you can find it anyway, the fix is very costly both in financial and political terms. All things considered, most problems just remain under the carpet.
For a comparable case. Think of the unwanted acceleration in the Toyota car. A software bug that caused multiple deaths. Toyota didn't admit to having any bug. The first audit found glaring quality issues but no explanation for the unwanted acceleration. It's only few years later that another audit identified how to trigger it, well, 10 different ways to make it happen.
If you read the long text and the attached documents, there are multiple software, hardware and design issues detailed. Some deadly ones around acceleration about tasks scheduling and priority inversion, well known aspects of embedded real time software with known solutions to avoid them.
The lead is well buried. That's another obstacle with non-trivial debugging. Nobody has the attention span, the time and the knowledge to understand non-trivial bugs, let alone when they're intentionally kept in the dark and pressured by companies.
I’m with you on this. If they allow this plane to fly again, I’ll be actively avoiding it when booking my tickets. Even if that means much higher ticket prices. It would take many years of flawless service of this plane to change my mind.
Bear in mind that most of the flying public aren't even aware that there's a problem, so the only issue is getting the airplane airworthy. PR is a "minor" issue that only affects the airlines and that segment of business travel that are aware of the problem. Don't forget that people forget stuff quickly because there's always something new to worry about.
And for me, personally? If the corrected airplane is deemed airworthy by the appropriate regulatory bodies, I'll have no problem flying on it.
>If the corrected airplane is deemed airworthy by the appropriate regulatory bodies, I'll have no problem flying on it.
I disagree, and I think this is really what makes the situation a far larger issue within the aviation community. It was approved by the appropriate regulatory bodies despite the serious failures by Boeing engineers and managers to identify and correct the MCAS problems before it was deployed into the field.
It's not a case of some crazy fluke that nobody knew was going to happen. This was a single sensor (aka a single point of failure) on a system that could nosedive a commercial airliner against the will of any human on or off board. You could ask anyone: "Is it a good idea to put a sensor on this plane that, if it malfunctions, will force the yoke forward and cause the plane to crash?" Not a single soul alive would think it is.
The fact that the FAA had the opportunity to tell Boeing to GTFO with this insane decision but didn't makes them a political body (i.e. pay for play, they wanted Boeing to generate 737 MAX sales even if it killed people) at worst and incompetent (they genuinely didn't realize the MCAS had problems) at best.
The FAA has, so far, miraculously avoided political controversies throughout its history and has always been regarded as a reputable, trustworthy body that deserves the privilege to regulate airways both in and out of U.S. territory. Losing their reputation could hurt air travel safety for decades to come.
You disagree that I'll have no problem flying on it ;-)
Look, I haven't worked in aviation electronics, but I have worked in another Federally regulated industry for a long time. Having "seen the sausage being made" as it were, none of this 737-MAX shenanigans surprises me. Perhaps that informs my opinions!
Ha, I suppose I can't change your mind! What industry have you worked in? I'm interested in your perspective and insights. After all I'm just armchair general-ing at this point.
I was a software engineer in medical devices for over a decade. The regulatory agencies (FDA and the various agencies in Ireland, EU and other countries) behave in a similar fashion to the FAA. They acknowledge that the practitioners in the industry have far more experience and familiarity with the product that they do, so by necessity, they act mainly as oversight.
In general, the industry is extremely quality-focused and would probably be so for a long time even without the oversight. That said, the companies will go to whatever length they can legally to not shoot themselves in the foot economically. So while I can't say that I know of any actual coverups or illegal behavior, I do know of cases where Problem Reports were analyzed to within an inch of their life to ensure that the business could legally and ethically avoid a product recall.
You're building extremely complex systems and even with a sincere commitment to quality, things will go wrong.
Is the 737-MAX fundamentally unsafe or poorly designed? I see nothing that even remotely hints at that.
>Bear in mind that most of the flying public aren't even aware that there's a problem, so the only issue is getting the airplane airworthy.
This might have been true in the first few days after the accident, but the 737 Max has been all over the news since… I would be shocked if a majority of fliers had not heard at least something about issues with Boeing planes.
The 737Max's design decisions seem to have been driven by their desire to maintain their 737NG type-rating.
So even though it is aerodynamically a different aircraft (with the engines further out), it mimics the 737NG with an effective emulator. For pilots certified on the 737NG, apparently minimal retraining is required to fly the 737Max.
Using this analogy, the MCAS system was seemingly put in place to behind-the-scenes manage a flight-envelope condition on the Max that would not happen on the NG.
So what happens when the 737Max hardware has a failure? How is the failure condition reported and managed by the flight crew? Are all failures on the 737Max passed through like they were 737NG failures? Does the flight crew respond as if they were flying a 737NG or a 737Max?
Correctly mimicing a 737NG during proper flight and under failure conditions seems like a tall order.
This is somewhat of a misunderstanding of the situation.
The 737Max was built to provide a more fuel efficient model compatible with all of the 737-sized gates and etc stuff airlines owned. They did this by slapping bigger engines on, but to make them fit they pushed them forward of the wing (can’t make the plane taller or it doesn’t fit all the etc it’s supposed to be compatible with).
Big, front positioned engines messed up the aerodynamics. Now, at speed, as a plane got closer to (but not at) the stall angle, forces suddenly inverted, and it became much easier to pitch up into a stall than push down away from it. This violated FAA rules that say for a commercial plane to be certified, at any point short of a stall it must always be harder to pull into it than push out.
Boeing decided to add some software to automatically push the nose down when you get to the force inversion point. This uses the stabilizers to add force to the stick, so the pilot always has that extra force making it easier to push out of a stall than pull into it, meeting the FAA requirement. This is MCAS.
Thus MCAS is in no way a “737NG emulator”. You could call the plane a 797 and you’d still need it to meet fundamental certification requirements about stick forces. Ie) it’s not so much mimicking an older 737 as it is just pretending to be a sanely designed commercial airframe at all.
The type certification stuff only enters into it when Boeing didn’t want to tell people about MCAS because it might have caused them to think harder about the need for more training, the lack of which was a selling point for them.
As I've mentioned at in other parts of the thread, a very thorough design review is at a minimum warranted.
As I've sat down and worked on reverse engineering, and reverse engineering things as best I can from pieces of technical info strewn hither and yon, I'm developing serious concerns over how far Boeing has actually gone in their FMEA.
Given their complete omission or misclassification of the Angle of Attack sensor, I can't really give them the benefit of a doubt that they actually thought through the consequences of more severe, but less likely occurrences like double flameout, or alternator failure. Both of which would represent another critical threat to the MCAS software; which must be active in order for the airframe to be asserted as airworthy.
Well we have such quandaries with yaw dampeners too. But yaw dampeners are not computer controlled. I think it's a substantial betrayal of FAR 25 if computers are being allowed to paper over aerodynamic defects or non-compliance with applicable FARs.
Using computers to aid safety, to reduce pilot workload, that's all fine. But to use them to certify an airplane as having certain aerodynamic behaviors when they do not really have those behaviors? Perverse.
And further, the software routine under discussion can in effect be neutralized, easily, in-flight, by flipping two switches. Is it really acceptable, by Boeing and the FAA, to render an airplane legally unairworthy by flipping two switches? And even more damning, to me as a pilot, is they apparently found it acceptable to require no training for the true behavior of the airplane minus this augmentation that is easy to disable inflight and is in fact recommended to be disabled as a memory checklist item for certain kinds of emergencies?
Seriously what the fuck?
If true it is wrongdoing. It's wrong for Boeing to go down that road, it's wrong for the FAA to permit it - until the FARs are changed. There should be public hearings and all kinds of regulatory requirements for expected computer and software standards, failure rates, redundancies, and other guarantees. We have such guarantees in writing for the physical aerodynamics of the airplane! There absolutely should be equivalents for computers and software if they are somehow going to take up the slack for otherwise inadequate aircraft design. You don't just get to silently wordsmith everything and say oh this computer thingy here will satisfy the aerodynamic requirement.
Fucking hell. It makes me angry. And that's why I really hope there is a misunderstanding, that really the airplane is certifiable as airworthy without any computer augmentation, and that the problem is merely that the pilots were kept out of the loop to avoid type rating required difference training. That's bad enough. But I think it's worse to paper over aerodynamic short-comings, waiving it off with computer augmentation when not a single allowance for that is made in the FARs.
It really seems beyond just negligent and greedy to me, it's almost like Boeing was just running a malicious social experiment just to see what they could get away with.
I understand the goals of the plane and how avoiding pilot retraining is more important than any other priority in the world of aviation, but even then the design is just so bad it's hard to even make sense of.
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[ 5.1 ms ] story [ 192 ms ] threadThe FAA in turn had been systematically delegating parts of the certification back to the manufacturers themselves, and obviously have not provided enough oversight.
After the crashes the EASA have obviously determined they need to redo the verification work themselves.
For example, I worked on a program where we certified the glass cockpit upgrade for the US Navy trainer, T-6A to T-6B with Transport Canada, the aircraft with the new avionics was certified by the FAA, and the whole system was then accepted by the US Navy. Satisfying all 3 stakeholders at the same time often proved difficult.
EASA trusted the FAA to do their job and actually check the plane before certifying it. The FAA instead gladly outsourced the certification to...
... Boeing.
Which ultimately leads to the loss of reputation for the FAA, which is why EASA is now checking the plane themselves and finding numerous faults with it.
It's like University A would tomorrow get rid of all teaching assistants because it's cheaper that way and just have students self-grade their exams. Everyone will hence have only A+ and everyone is happy. Until finally a lot of really bad University A students will leave the job market unimpressed and thus hurting the reputation of University (FA)A.
Am I the only one who sees this as a grand fuck up that only has one outcome? And it's certainly not what they are trying to sell the public on.
Of course that's not going to happen. There is simply way too much money involved and way too many interests to allow Boeing to take that kind of hit.
It seems like the airline industry is surviving without this substantial number of planes in their fleet. Have prices surged for the old 737-MAX routes? Have companies taken out more debt to put in orders for Airbus and Bombardier replacements, or are they confident the existing stock will return this year?
The 737 did survive their rudder issue several decades ago. Maybe this new generation of 737 will survive this? I'm sure there are a number of people who will avoid booking flights on these jets if they can though, at least for several months or a year.
at the risk of being obtuse, why, and who?
Why do you think this was a best-selling plane for Boeing? Who's buying it, and why?
The answers to that question and yours are the same: airlines want to decrease operational costs, of which pilot training and specialization is a huge component.
tempguy9999 happens to fancy a bottle of spirits right now, it is the weekend after all.
tempguy9999 pops down the road to the local offy (short for off-license, brit-english for place that sells booze), and being skint at the moment, I ask for the cheapest thing that will get me sloshed.
Sales bod suggests x. I buy x. I drink x and go to hospital because x contains a big dollop of methanol.
I went to (what I honestly thought was) a reliable supplier that's sold me loads before with perfect satisfaction, and got something dangerous. I did not know it was dangerous, nor was I told it was dangerous. Also, that supplier had a world-class reputation.
I don't accept it's Southwest/Ryanair's fault at all.
respectively yes, and, can you show me what southwest actually asked for that was so extreme?
edit: actually, I'm not sure. If mcas had worked correctly (including being documented) then 2 planeloads of people might not have been dead, but AIUI it fought the pilots and sadly won.
The worst part for Boeing is that now under additional scrutiny more problems are being found, that begs the question what else is being missed?
The problem with the Max is that Boeing favoured the major airlines that wanted 2010s technology in a 60s airframe. But guess what, that doesn't work, in the same way you can't turn a Thunderbird into a Tesla by "just plugging a new engine".
Not that Boeing probably didn't have a vested interest in not investing in a new airframe and preferred the lowest cost project
Now if they can call the Max the 737-2, cut the legacy crap and work around the longitudinal stability by breaking backwards compatibility (and sell the plane at a discount) they could end up with smaller losses
No, the problem with the plane was that Boeing engineered a crappy solution to a problem they had.
There were 3 major problems that I am aware of.
1) A powerful(flight control wise) automated system that relied on one source of sensor data when multiple are available.
2) The switches that disabled the automated system also disabled all electronic control for the elevator trim, making it much harder for the pilots to recover from an out of trim condition.
3) The normal elevator controls are not enough for the pilot to overcome the out of trim condition so pulling back on the yoke as far as possible would not pitch the plane up enough to regain altitude.
The only way to recover from this type of situation is to momentarily pitch the plane further downwards to take stress off of the elevator trim so the manual controls are easier to operate with your hand. You would have to do that enough times to get the plane back into a stable position, this is not always possible when the plane is already at a low altitude.
Why did they have issues with MCAS? Why did they even need MCAS again?
Because they tried to fit bigger engines onto a 60s airframe that is not fly-by-wire.
If the plane was FBW, no MCAS needed.
If the plane had a bigger ground clearance, no MCAS needed.
> The normal elevator controls are not enough for the pilot to overcome the out of trim condition
I don't think there is a plane where they are, they also move more slowly than the elevators.
A plane should be airworthy even if the majority of it's automation has suffered a casualty.
Yes, but you wouldn't need MCAS for maintaining longitudinal stability
> in it's (sic) minimally "assisted" state should demonstrate basic airworthy characteristics.
If that was the case the Max would not be certifiable, MCAS or not
MCAS was Boeing’s idea of a solution to this; command the stabilizers down to provide counter force against the stick, making it harder for the pilot to pull into the stall than pull away from it at every point.
Even if the 737NG had never existed and the 737MAX as it exists today were for some reason an all new design, it would need the MCAS counter-force to get certified as air worthy no matter how much new training pilots got. It (claims to) solve a fundamental airworthiness requirement; it is not a “737NG emulation feature” as some mistakenly believe.
Keeping the type rating means that they needed to avoid making completely new wings or significant fuselage changes, which would require a new type rating as well.
All of that led to fitting engines in a way that caused a bunch of aerodynamics problems, which led to crappy solutions.
The economic incentives started it.
It’s really not maintaining the type certification that’s the problem, it’s the aerodynamics of the airframe. If they’d called it a 797 from the beginning it would still have needed the MCAS to get FAA approval because the insane aerodynamics mean the stick forces don’t obey the regulations for constant increase in forces approaching a stall. The MCAS isn’t there just so it can pretend to be a 737.
So yeah changing the name is only a solution if by changing the name you mean fundamentally changing every aspect of it.
I don't think you understand the regulatory regime. Changing the name, creating it as a new airframe, means total top-to-bottom re-certification. That means they can ditch all the legacy equipment and start the control system from scratch. Most of the problems with the max atm are related to systems layered atop that legacy equipment (autopilot, control surfaces etc) that cannot be swapped out without changing the type/name.
The fucking name isn’t the problem. Trying to work fuel efficiency into too small a package and ending up with something with the stall characteristics of a brick is the problem. Creating it as a “new airframe” fixes the problem only by abandoning the problem they set out to solve, which again, wasn’t “keep the name”.
If this had been the 797 from the getgo, but had tried to put those engines on any airframe that stayed that low to the ground for gate compatibility, they have still needed the MCAS because of the aerodynamics of the necessary engine placement.
Remember that the 737 is such a big seller because it has huge usage on regional routes and in smaller countries. It lands at airports where they still wheel up a set of stairs, or one of those double-decker deplaning buses. The height is a big deal for established infrastructure of customers. If it weren’t, they could have redesigned the landing gear to get the necessary engine clearance instead of fucking up the aerodynamics by moving the engines.
The height, and not the name, is the original sin from which every shitty consequence flows.
The popular way is with a T-tail and podded engines off the sides of the rear of the body. Boeing has produced such an aircraft. https://en.wikipedia.org/wiki/Boeing_717
Another way is with a high-mounted wing. This is popular for military cargo jets, such as the C-5 and C-17.
Putting engines above the wing is an option. Boeing did it for the YC-14, Antonov did it for the An-72, VFW-Fokker did it for the 614, and Honda did it for the Hondajet.
The landing gear could have be made to stick out extra long for the takeoff and landing, but then partially retract for passenger boarding. During passenger boarding, the aircraft could even sit on the engines.
And a type certification isn't the only way to require additional training. For sure there are meaningful differences between the 757 and 767, despite sharing the same type certification, and pilots do go through that difference training. There are numerous examples of this.
Where Boeing probably wants to be, is in the vicinity of the regulatory distinction between the A320 and A320neo. It seems really unlikely to me that any 737 NG to 737 MAX transition training burden, is going to approach that of 737 NG to A320neo transition training.
No aerospace engineer worth their salt would have designed the MAX as is given the freedom to reconfigure and avoid all the problematic aerodynamics inherent to the design entirely.
They went fast to beat Airbus, cheap as the total cost of the package (plane + training + etc ...) and therefore quality takes a hit.
It happens everywhere but I think we were all under the assumption that surely this industry wouldn't stoop as low.
I've been told a while ago that the engineering of planes involved a fair amount of "duct-tape" (used loosely here) to make all of it work despite the risk involved. I didn't think much of it.
Now I sure have a different take on those words. While growing up plane crashes that happened were rare or their own kind of event(9/11, german pilot suicide, MH370). Therefore people around my age (30) might have bigger faith in planes than one should expect from travelling in hundred of tons of metal, composite materials and fuel going 500+ MPH in the sky.
1) delegation from FAA to "Boeing internal"
2) poor communication during the design and/or poor review of the decisions made in earlier stages
3) the deliberate taking of shortcuts (changing the amount of correction the MCAS without documenting it or re-running proper tests/verifications)
4) the use of this or that verbal/lexical workaround to avoid a re-certification of the plane, which essentially ended up in hiding info from the pilots
The problem is not limited to the specific issue, the above are IMHO clear signs of a (deviated) modus operandi from the company (but possibly also from the FAA), the same mis-management may have caused (or may not, but there is no way to know) tens of other potential issues that by sheer luck have not caused any accident to date (or have not yet been noticed because they only happen in corner cases).
Previous (historical) recalls and modifications to Boeing airplanes (often mandated - after an accident - on the basis of NTSB reports) were - AFAICR/AFAIK - mistakes "in good faith", this one seems like the result of a general lowering of the processes.
http://newsinflight.com/2019/07/06/easa-has-outlined-five-re...
Given half of pilots will be below average... that doesn't sound great. Shouldn't it be all pilots have strength enough.
But like you, I'd still like margin for error (pilot with a cold, fatigued, under other stress, etc.)
Average is different than median.
It's about: is the required strength on par with the required dexterity and strength needed for other tasks the pilots need to do?
That means time is a factor that has to be taken into account. There are configurations where a mistrim flat out cannot happen at a certain altitude or it isn't recoverable in time before hitting the ground, regardless of strength.
Female pilots and pilots from ethnic groups of smaller stature also need to be considered.
The FAA First Class Medical requirements don't seem to have any requirements regarding physical strength.
Then FAA would fight back and everyone loses, for now there is no reason to doubt the issues raised so let's wait until say Europeans raise some bogus reason and then accuse them. though so far FAA and Boeing are the ones with less credibility (since were trying not to ground the MAX even with 2 planes crashed)
That’s two interesting other countries, presumably chosen because the presence of Bombardier and Embraer mean Canada and Brazil have some experience in certifying planes? Notably missing are Russia and China who also make planes
https://en.wikipedia.org/wiki/CRAIC_CR929
Notice at the same time, not only the manufacturer, but also the authority CAAC, the China counterpart of FAA, is behaving more and more independently, as the first regulatory agency to ground 737MAX.
China has 96 737MAX8 then, more than any other country. They have both the most to lose and gain.
>Them being proactive is really only because of politics.
Do you think perhaps them being proactive could have a small little tiny bit chance of caring about safety, or only because of politics?
Personally I don’t love the idea of flying on one of these at this point, no matter how many tweaks they make. I’m sure many others will feel the same.
At what point is a new airframe the better PR move for all involved?
4,500 orders (edit: potentially) cancelled, any thoughts what that would do to planned income?
I already use sites like seatguru.com to work out the best seats on flights - I guess I'll now be checking to see if it is a boeing plane or not before booking.
Now if the 787 is grounded or loses ETOPS certification, that'll be a much bigger hit for the big US airlines.
If Boeing can't afford to scrap 500 jets, it probably can't afford to sell 500 jets at a 95% loss.
Nobody likes a cargo plane falling on them.
The worst case scenario (for Boeing), at this point, is the FAA and/or other aviation regulators, decide that the differences require different type certification for the aircraft and therefore mandate a unique type rating by pilots to fly the plane. That would require they be trained about those differences.
The actual risk is complex, an airline with more capacity depending on the new model has more risk as they take on new planes and retire old ones, but does the contract reflect that complexity? I have no idea. For all I know, there's generic terms for handling all certification problems that crop up, including airworthiness directives from the FAA that affect A&P's rather than pilots. It might be the two sides split the cost 50/50 for all I know, or maybe they use binding arbitration to keep the airing of dirty laundry as much out of the public view as possible.
And
https://www.seattletimes.com/seattle-news/times-watchdog/the...
There are more than enough reasons to reasonably decertify the aircraft. When you start doing things that "fly-in-the-face" of industry best practice, and begin requiring the most liberal interpretation possible of regulations as written, it's time to start dialing back what you're willing to let slide.
Even with these "minor tweaks" to every fuselage, the airframe can reasonably be assumed to have further problems.
As a for instance, what happens if a dual flameout in flight occurs? Does the Ram Air Turbine make enough power to run the Flight Control Computer and all it's dependencies to ensure the MCAS functionality stays intact until the plane can be safely touched down?
If not, will there be simulator training so pilots are prepared?
There is more than enough publicly available information to be cause for concern.
Isn't MCAS a solution to address greater nose pitch-up due to stronger thrust vectoring effects from the new engines? In a dual engine flameout where all thrust is lost, doesn't thrust vectoring cease to be an issue?
That's why this damn kludge of a system is so concerning. It's an active airworthyness hack to counter a passive aerodynamic characteristic of the airframe.
So if a double flameout occurs, killing all power, and killing the Flight Control Computer due to unreliable voltage being supplied from the Ram Air Turbine, the pilots are stuck flying a glider that'll try to pitch into a stall on them if they aren't careful.
Again, normally wouldn't worry about something like this, but they missed/intentionally left out the single AoA sensor...
So...yeah... I have severe concerns about this design, and the effort put into known, unlikely, but highly severe failures.
Maybe you shouldn't post such strong statements about a technology you know very little about.
First: The 737 does not actually have a RAT.
Second: On types that have a RAT (e.g. the A320) it isn't electrical, it provides hydraulic power to operate the flight controls.
If you need emergency electrical power from a RAT equipped aircraft it will be from an haudraulically driven AC generator through a constant speed drive. It will not have voltage fluctuations, only risk is frequency being off and aircraft systems are designed to deal with that.
The article you cite doesn't even mention FAR 25. The strongest statement it makes is this: “to address potentially unacceptable nose-up pitching moment at high angles of attack at high airspeeds,”
For my purposes, that whole statement is rendered useless bullshit by the word "potentially". It's like saying "maybe, maybe not, who is to say?"
That statement in the article implicates the 737 MAX as not conforming specifically with FAR 25.173(c), but does not come right out and say that. Further, no source has said, one way or another, that the FAA permits computers as an aid to certifying airworthiness for designs that without computers would not be certified under FAR 25.
There is not enough public information to decertify the plane. Realize exactly what you're really saying: the airplane should not have been certified airworthy to begin with. You can't really decertify it without, in effect, saying malfeasance has happened. It isn't merely that MCAS wasn't good enough. It's that it should never have been considered appropriate to use software to paper over aerodynamic problems in the first place.
Am I suspicious that's what has happened? Yes. But is my suspicion evidence or a relevant fact that demonstrates it has happened? No. And all we have with articles thus far is speculation and suspicion. Where are the facts that prove this?
I can't account for what pile of fecal matter will be shoveled on the FAR's to justify the MAX, and to be honest cmurf, I believe it was a post of yours that ended up galvanizing for me that something is incredibly wrong with the MAX. The fact is, regulations in the United States seem to become negotiable after a certain size actor starts coming into play, and like it or not, that's the way it's worked since I've been around to see it.
Seattle Times found documented proof of non-compliant curves. You might find 'potentially' magically turns something into 'bullshit', but as someone who works in risk management, and is well versed in the physical sciences, "potentially" means that something is likely enough not to be trivially discounted, and requires an effort to remediate. It means "the potential exists; there is no known law or other invariant that reasonably discludes or prevents outcome X from being the case". If there is anything to being an Engineer, you have to admit that the the word "potentially" means something coming from them.
Seattle Times also broke the story on how Boeing regressed switch functionality in order to make sure the Stabilizer Trim cutout procedure lined up with what was already documented, but failed to provide educative material as to why the change, or also ensuring that pilot's who knew they could isolate the autopilot from the trim motor without cutting out their trim switches no longer could.
60 Minutes reported on active attempts to circumvent FAA scrutiny (decision to go with the single sensor input). I won't go as far to put names on actors, but there is more than enough stink of malfeasance that the poor engineering decisions, the motivations behind changing the focus of the company from high quality aircraft design to shareholder value generator, and the actions of current regulators in dragging their feet to deal with the problems that have been uncovered should stoke righteous indignation at the nerve of people who purport themselves to be responsible stewards of the public's safety to be so sheepishly approaching what is one of the biggest demonstrable breaches of the public trust of our time. These are not suspicions. These are not suppositions. This happened. You want to know where the facts are? Grab a pencil, some paper, and a computer, and crack open a few books on aerodynamics, numerical methods, CFD, and simulations. Then, run down as many dimensions as you can. This will act as the foundation for your coming aerodynamics analysis. Read through some white papers. Reason. Look at different plane designs, understand how different trade-offs effect the machine.
Don't feel like becoming an aerodynamicist in all but the job/paycheck? Then you'll have to live with the outputs generated by the media like everybody else, or say screw it, and do your best to understand the science anyway.
You can wait for the lawyers; I've worked through enough to assure myself that if the rest of the world dropped the issue tomorrow, I'd still not put anyone I cared about on those planes on principle, and on the basis of too many unanswered questions. I have no compulsion to do anything to help Boeing's image, and the shots I fire I ensure have sufficient grounding in what is reasonably deduceable from publicly available information to not be a bad faith hindrance. If they want things cleared up. They can put all the information where God and everyone can see it. The concern with the RAT being deduced from the Gimli Glider iincident; where the electronics getting knocked out ended up leaving pilot's with very few automation aids to land the plane. Just because it happened due to a fuel screwup doesn't mean it's outside the realm of possibility of happening from somethi...
Also, the thrust change nose-up moment is not much different to a 737 classic or 737 NG; MCAS is required due to the lifting moment of the engines, which are in front of the center of gravity (thus pulling the nose up when in a positive AoA situation).
Edited to add: the rudder design was "new" to the industry, in that it had a single control surface activated by a single control mechanism with no redundancy (sound familiar?). The rudder control valve in question had been found to malfunction on 747-200's earlier and was replaced in the entire 747 fleet. The 737's were not replaced until after more fatalities.
The point of all this is that there are "incompetence" narratives that can be woven around all major design issues in commercial aircraft. To say "I'll ever fly one" displays a lack of understanding of what makes commercial aviation the safest way to travel, and what the risks actually are.
No right-minded person would ever design a flight control system like that. It's not merely wrong but wrong in such a basic way, as if designed by a child.
Such a situation reasonably makes people question whether the MAX project was managed by competent individuals, which is obviously a prerequisite for many people to fly in one.
https://i.imgur.com/lLLeldA.png
Source: https://qz.com/1571820/deaths-on-the-boeing-737-max-8-vs-oth...
The question here is likelihood of fatal accident, which is not addressed by your source.
They had the exact same number of crashes, plus one near-crash. Very similar to me. Planes flew with much lower passenger loads in those days so total fatalities can differ.
I don't know what the exact crash rate (i.e., % flights that end in hull loss) was.
That's just what's on the wiki page [1]
[1] https://en.wikipedia.org/wiki/Boeing_737_rudder_issues
I provided a list of fatalities, you said that was a bad measure and early 737 was a worse plane that crashed more often. Do you have stats for that?
Some design flaws take time to show up, due to life cycle aging. Most of the rudder issues were in 737-300's, which began full production in the mid-1980s. There isn't just a single "737" model, even for the same 737-XXX series.
You can do your own research from here on out. If 6 fatal crashes plus non-fatal incidents due to the same design flaw don't persuade you then perhaps you are not persuadable.
The basic fact, that there are plenty of previous cases of serious design flaws in aircraft that became quite safe, is sound, whether you choose to accept that or not.
I would rather fly on one of these once they're back in the air.
The alternative to found and fixed issues is not a lack of issues.
An issue can be extremely difficult to identify and understand in the first place. Assuming you can find it anyway, the fix is very costly both in financial and political terms. All things considered, most problems just remain under the carpet.
For a comparable case. Think of the unwanted acceleration in the Toyota car. A software bug that caused multiple deaths. Toyota didn't admit to having any bug. The first audit found glaring quality issues but no explanation for the unwanted acceleration. It's only few years later that another audit identified how to trigger it, well, 10 different ways to make it happen.
If you read the long text and the attached documents, there are multiple software, hardware and design issues detailed. Some deadly ones around acceleration about tasks scheduling and priority inversion, well known aspects of embedded real time software with known solutions to avoid them.
The lead is well buried. That's another obstacle with non-trivial debugging. Nobody has the attention span, the time and the knowledge to understand non-trivial bugs, let alone when they're intentionally kept in the dark and pressured by companies.
Bear in mind that most of the flying public aren't even aware that there's a problem, so the only issue is getting the airplane airworthy. PR is a "minor" issue that only affects the airlines and that segment of business travel that are aware of the problem. Don't forget that people forget stuff quickly because there's always something new to worry about.
And for me, personally? If the corrected airplane is deemed airworthy by the appropriate regulatory bodies, I'll have no problem flying on it.
I disagree, and I think this is really what makes the situation a far larger issue within the aviation community. It was approved by the appropriate regulatory bodies despite the serious failures by Boeing engineers and managers to identify and correct the MCAS problems before it was deployed into the field.
It's not a case of some crazy fluke that nobody knew was going to happen. This was a single sensor (aka a single point of failure) on a system that could nosedive a commercial airliner against the will of any human on or off board. You could ask anyone: "Is it a good idea to put a sensor on this plane that, if it malfunctions, will force the yoke forward and cause the plane to crash?" Not a single soul alive would think it is.
The fact that the FAA had the opportunity to tell Boeing to GTFO with this insane decision but didn't makes them a political body (i.e. pay for play, they wanted Boeing to generate 737 MAX sales even if it killed people) at worst and incompetent (they genuinely didn't realize the MCAS had problems) at best.
The FAA has, so far, miraculously avoided political controversies throughout its history and has always been regarded as a reputable, trustworthy body that deserves the privilege to regulate airways both in and out of U.S. territory. Losing their reputation could hurt air travel safety for decades to come.
Look, I haven't worked in aviation electronics, but I have worked in another Federally regulated industry for a long time. Having "seen the sausage being made" as it were, none of this 737-MAX shenanigans surprises me. Perhaps that informs my opinions!
In general, the industry is extremely quality-focused and would probably be so for a long time even without the oversight. That said, the companies will go to whatever length they can legally to not shoot themselves in the foot economically. So while I can't say that I know of any actual coverups or illegal behavior, I do know of cases where Problem Reports were analyzed to within an inch of their life to ensure that the business could legally and ethically avoid a product recall.
You're building extremely complex systems and even with a sincere commitment to quality, things will go wrong.
Is the 737-MAX fundamentally unsafe or poorly designed? I see nothing that even remotely hints at that.
This might have been true in the first few days after the accident, but the 737 Max has been all over the news since… I would be shocked if a majority of fliers had not heard at least something about issues with Boeing planes.
So even though it is aerodynamically a different aircraft (with the engines further out), it mimics the 737NG with an effective emulator. For pilots certified on the 737NG, apparently minimal retraining is required to fly the 737Max.
Using this analogy, the MCAS system was seemingly put in place to behind-the-scenes manage a flight-envelope condition on the Max that would not happen on the NG.
So what happens when the 737Max hardware has a failure? How is the failure condition reported and managed by the flight crew? Are all failures on the 737Max passed through like they were 737NG failures? Does the flight crew respond as if they were flying a 737NG or a 737Max?
Correctly mimicing a 737NG during proper flight and under failure conditions seems like a tall order.
The 737Max was built to provide a more fuel efficient model compatible with all of the 737-sized gates and etc stuff airlines owned. They did this by slapping bigger engines on, but to make them fit they pushed them forward of the wing (can’t make the plane taller or it doesn’t fit all the etc it’s supposed to be compatible with).
Big, front positioned engines messed up the aerodynamics. Now, at speed, as a plane got closer to (but not at) the stall angle, forces suddenly inverted, and it became much easier to pitch up into a stall than push down away from it. This violated FAA rules that say for a commercial plane to be certified, at any point short of a stall it must always be harder to pull into it than push out.
Boeing decided to add some software to automatically push the nose down when you get to the force inversion point. This uses the stabilizers to add force to the stick, so the pilot always has that extra force making it easier to push out of a stall than pull into it, meeting the FAA requirement. This is MCAS.
Thus MCAS is in no way a “737NG emulator”. You could call the plane a 797 and you’d still need it to meet fundamental certification requirements about stick forces. Ie) it’s not so much mimicking an older 737 as it is just pretending to be a sanely designed commercial airframe at all.
The type certification stuff only enters into it when Boeing didn’t want to tell people about MCAS because it might have caused them to think harder about the need for more training, the lack of which was a selling point for them.
As I've sat down and worked on reverse engineering, and reverse engineering things as best I can from pieces of technical info strewn hither and yon, I'm developing serious concerns over how far Boeing has actually gone in their FMEA.
Given their complete omission or misclassification of the Angle of Attack sensor, I can't really give them the benefit of a doubt that they actually thought through the consequences of more severe, but less likely occurrences like double flameout, or alternator failure. Both of which would represent another critical threat to the MCAS software; which must be active in order for the airframe to be asserted as airworthy.
I'm just not buying it.
Using computers to aid safety, to reduce pilot workload, that's all fine. But to use them to certify an airplane as having certain aerodynamic behaviors when they do not really have those behaviors? Perverse.
And further, the software routine under discussion can in effect be neutralized, easily, in-flight, by flipping two switches. Is it really acceptable, by Boeing and the FAA, to render an airplane legally unairworthy by flipping two switches? And even more damning, to me as a pilot, is they apparently found it acceptable to require no training for the true behavior of the airplane minus this augmentation that is easy to disable inflight and is in fact recommended to be disabled as a memory checklist item for certain kinds of emergencies?
Seriously what the fuck?
If true it is wrongdoing. It's wrong for Boeing to go down that road, it's wrong for the FAA to permit it - until the FARs are changed. There should be public hearings and all kinds of regulatory requirements for expected computer and software standards, failure rates, redundancies, and other guarantees. We have such guarantees in writing for the physical aerodynamics of the airplane! There absolutely should be equivalents for computers and software if they are somehow going to take up the slack for otherwise inadequate aircraft design. You don't just get to silently wordsmith everything and say oh this computer thingy here will satisfy the aerodynamic requirement.
Fucking hell. It makes me angry. And that's why I really hope there is a misunderstanding, that really the airplane is certifiable as airworthy without any computer augmentation, and that the problem is merely that the pilots were kept out of the loop to avoid type rating required difference training. That's bad enough. But I think it's worse to paper over aerodynamic short-comings, waiving it off with computer augmentation when not a single allowance for that is made in the FARs.
I understand the goals of the plane and how avoiding pilot retraining is more important than any other priority in the world of aviation, but even then the design is just so bad it's hard to even make sense of.