On the recent two crashes of Boeings 737 Max

[Skybird]

https://www.zerohedge.com/news/2019-...tware-engineer

Nevertheless its a big damage for Boeing and could lead to punitive measures in the legal verdicts, whioch would effectively tripüle the costs thery would need to pay out.

In the early 90s, the aircraft company Piper went bancrupt due to such a punitive measure, which is a special characteristic in American law.

The close relation between Boeing and the Us government and its authorities, the closeness of producer and controlling authorities, even the political laziness of letting producers "control" themselves (pharmaceutical industry...) , is a general problem, no matter what the causes for the crashes are.

The competition between the 737 Max and the Airbus 320 Neo is tough, Airbus currently is in the clear lead in number of orders. Pilots of other nations and carriers have complained about inadequate documentation provided by Boeing and inadequate or non- existent training on the Max's characteristic features. Thats why I think the above linked explanation chain is only one aspect of the total picture.

If Boeing hoped to gain any form of lead or avantage due to the A 380 project ending in a disastrous economic failure (the German subsidies will not be paid back, its lost money for the German tax payers), this hope now has collapsed. The 737 affair has the ingredients to be really crippling . If politics do not interfere of course, which they likely will do.

This is focussing on the possibility of inadequte cetification due to time pressure and Boeing wanting to react to the challenge by Airbus'S A320.

https://www.seattletimes.com/busines...ion-air-crash/

[Catfish]

Both good links. It also shows it is dangerous to circumvent or give up certain approved procedures or designs.
I can only guess how those pilots must have felt when they tried to switch off the system when it switched on again and again, with the trimming wheel turning.
Politics, well.. someone will be sacrificed to say "i take responsibility", and this will be all.

[Aktungbby]

between Boeing and the ’ kissin cousin' FAA's 'apparent lack of impartial integrity in approving the craft and it's faulty MCAS, a universal truth of aviation holds true: profits first...sardine packed expendible passengers second...small wonder the Ethiopian investigators have turned over the flight recorder data to the French to avoid a FAA cover-up!

[Jimbuna]

Originally Posted by Catfish

Both good links.

Indeed, great

[Rockin Robbins]

To make matters even worse, it appears that there are two angle of attack sensors, one on either side of the fuselage and only one of them was hooked up to the MCAS system, with no warning that the sensor didn't agree with other autopilot systems. In addition MCAS was much too powerful, able to overpower pilot input and set stabilizer trim to FULL down.

However there is a stabilizer trim cutout switch in the same position it has been for more than 30 years of 737 production. The proper procedure for an MCAS malfunction is just to throw that switch, which every 737 pilot in the world, regardless of airframe series, knows where it is. That's easy to say sitting behind a computer.

Here's the perspective for why confusion in the pilot seat (actually hyper-focusing and blocking out "irrelevant" things that busily kill) you is sometimes a fatal affliction and why having a jump pilot (one saved the flight previous to the fatal crash!) is a great idea. This is the absolute best source of info on this lousy situation and also shows that Airbus isn't immune from pilot tunnel vision either. Subscribing to this guy's You Tube channel is a great connection to the developing situation.

[Skybird]

Latest theory is about blowback, meaning that the plane gained so much speed that the airstream hitting the ailerons defeated the hydraulic pressure of the system trying to move them - the plane than practically is uncontrollable and cannot be saved by pilot input if it does not by lucky events loose speed again before the hydraulic system suffered unrepairable damage already.



That speed could have been accumulated due to chnaged geometry due to bigger engine size - with the whole design not having been properly tested and the MCAS having been an improper attempt to fix it with - a not properly tested software solutionb that additionally was not properly advertised to avoid cetifcaiton delays and so was not properly included in pilot instructions.


A report in Der Spoiegel today said a former Boeing engineer said that the pressure was immense and worse than ever before when some years ago Americna airlines planned to buy Airbus A320 Neos. Boeing needed a quick reply to counter that threat and the result weas that they did this re-engineering project, but in less than half of th etime that itr would have needed if all internal security rpoutines by Boeing would have been followed. In other words: Boeing broke its own standards and security orutines, and lied about it to the authorities. Also, cockpit modernisation steps that would have been in demand were left out, due to time pressure.



When I red about it it reminded me of the problems of fighter pilots in WWII vintage aircraft who may have dived so fast unto their targets that they could not pull in time anymore since they had left the speed envelope inside which they could still move the flaps and ailerons with the stick. Battle of Britain 2 was a simultaion simulating this effect - it was terrifying at times.



When the blowback thing is true, the whole design of the aiframe is in question , and just some addings to the code of the MCAS most likely cannot fix it. And after 300+ people dead and two planes lost under identical conditions of malfunctioning.


It looks very much as if Boeing made a big, huge pile of self-made poo on its doorstep. It could turn out to become much more hurting for Boeing than the A380 that led Airbus into a dead end. First airlines have called for cancellation of their orders - and its no big guess that they will go with the A320Neo instead.

[Rockin Robbins]

Originally Posted by Skybird

Latest theory is about blowback, meaning that the plane gained so much speed that the airstream hitting the ailerons defeated the hydraulic pressure of the system trying to move them - the plane than practically is uncontrollable and cannot be saved by pilot input if it does not by lucky events loose speed again before the hydraulic system suffered unrepairable damage already.

What caused the pilot not to be able to be recovered was the trim system being too powerful, exerting forces too great for pilots to overcome, even at normal flying speeds. This has been a possibility during the entire 737 series manufacture, over 30 years.

In the event of a trim overrun, the stabilizer trim cutout switch is and has been in the same exact location all that time. Throwing that switch results in immediate recovery of the pilot's ability to fly the plane, as shown in the flight previous to the fatal crash, where a third pilot in the jump seat evaluated the problem and knew what to do. As blancolirio said in the video I posted, it was the addition of the pilot in the jump seat that made the difference.

The plane can be flown safely. Now it's up to Boeing to ensure that it always is. Pilot error can crash any plane. This was clear pilot error. The question is "was the pilot error a predictable consequence of Boeing's or the airline's procedures, and what must be changed to keep this from happening again?"

From Boeing's standpoint, the trim system is too powerful. The trim system is more powerful than any possible pilot input. A pilot should be able to overcome the trim by using stick position only, thereby buying the time to analyze the problem in a stress-free mindset.

Secondly, with two angle of attack sensors outside the fuselage, hooking only one of them to the MCAS system just makes no sense. Error handling is absolutely essential to the functioning of any system and unquestioningly accepting the word of a malfunctioning sensor with no backup is an obvious failing.

Then the decision to have two systems, the light indicating autopilot/angle of attack sensor disagreement and the cockpit angle of attack display as optional equipment is also obviously faulty.

The kicker is that Boeing already advised pilots that MCAS malfunctions should be treated as a trim overrun situation and the stabilizer trim cutout switch should be switched off. Simple simulator runs should have revealed the fact that in an MCAS malfunction, the pilot is simply too busy trying to save his and his passengers' lives to think clearly.

The information you need to know to understand this situation is in the video I provided. It is self-validating, from a professional pilot who knows his business.

[Rockstar]

So the 737 has been around since '68 and the MAX since 2016. I imagine the number of 737max flights emanating from more used and well known airlines in western nations far far outweigh the number of flights from airlines out of Indonesia and Kenya. Yet from these lessor known third world countries come two crashes not very far apart from one another. Who the hell is responsible for signing off on these pilot qualifications which allows them to fly the plane?

[Rockin Robbins]

Originally Posted by Rockstar

So the 737 has been around since '68 and the MAX since 2016. I imagine the number of 737max flights emanating from more used and well known airlines in western nations far far outweigh the number of flights from airlines out of Indonesia and Kenya. Yet from these lessor known third world countries come two crashes not very far apart from one another. Who the hell is responsible for signing off on these pilot qualifications which allows them to fly the plane?

Interviews with American 737 pilots has shown that a decent number of them also would be taken by surprise MCAS malfunction. There might be better response by most, but I don't think that would mean nobody dies.

One advantage the American and European pilots would have is their airline companies' emphasis on lots of simulator practice. Those simulators are great for studying rare malfunctions and getting proficient at handling them. I doubt the Indonesian and Kenyan airlines have such resources.

[Skybird]

As was reported repeatedly by now, trainign on changede MCAS was not conducted by Boeing to save time and to not oput cetification in danger. If they would have trained it, it would have delayed certification.



The Blowback theory I mentioned is NOT just trim overriding pilot inpout. That is a possible issue in itself. It was deliberatekly desc ribed over here that the blowback theory, accpording to the meaning of the term as it is usually used, indeed means that the floight attitude of the plane is such that airspeed over the wings is so high that it defeats internal hydraulic system pressure - the system cannot move the ailerons and rudder anymore.



We talk abotu two different explanation theories ther,e RockingRobbins. Possible hthat they also mutually fed back on each other.


I just repeat what was written in two quite insightful German article two days ago. The one was authored by a former Boeing engineer, the other by a German Luftwaffe pilot. Both described the Blowback thing identically. They did not say it was like this - they just say it could have been like this, and that the flight behaviour of both planes seem to speak for it.


Boeiong has had a striong itnerest to bypass usuall secirotyplannings ans the time they need, the pressure, said the engineer, was immense, and the worst he had ever experienced in his career. I woul,d assume th econmic oressure to poush the 737Max still out, is still existent, even more so right now. So I would not enteriley trust in Boeing theories alone that thus are suspicious of trying to paint the picture such that a simple solution like ansoftweare update alone can brign the aircraft off the ground again. Even after the second crash they wanted to fly on and it was external fact finding that forced them to stop. Boeing, government Perntagon are way too close in this. Eisenhower, anyone?

[Rockstar]

Indeed this is a very unfortunate accident and I suppose it could be a technical, design, political or economic issue with the aircraft or maker. But if history is any judge it leans towards pilot error.

[Skybird]

Pilot error? No, that would be cheap. It is not one acident, but two, and they both seem to have run the same way, and Boeing seems to bare a devastating ammount of respinsi8blity for having provked them: by making quesitoinbable design decisions, by violating iut sown estlbisahed security routiones, schmees and timetables, by not properly adressing the chnaged geometry of the comolete airframe due to the bigger engines that had to be moved forward - and in order to avoid further delays in certification due to proper pilot training, denying that there would be any need to train pilots and thus pilots being left in th eunknown about vital chnages in handling procedures.

That is not just accidental - that is criminal.

The pilot can only use knowledge they have been provided with. And Boeing seems to have not provided them with what was needed. To accelerate the certification process. To catch up with Airbus soaring list of orders.

Airbus today sold 300 more to China. Severla carriers said they ask for comepnsations from Boeing, or even cancellation of their preorders.

The responsible decision makers at Boeing who designed this obviously overly rushed timetable during developement - quoted Boeing engineer said they (the engineers and designers) had to complete the task of designing the Max model in less than half as many years than such a task usually would be planned for - must see prison from inside for many, many years to come. They killed over 300 people.

Not "pilot error". Its "manager error", or better: manager betrayal of the certification authorities.


Really. To me its not two accidents here that happened, and it is not the pilots who are guilty here, they are just the pawns that some higher beings want so sacrifice now to save their own reputation. Its a crime what has happened.


But maybe Boeing is just too big to fail - or too big to be held responsible. If they would face indeed punitive sentencing, which effectively triples the sentence volumes, the financial damages nevertheless would make the bones even of a giant like Boeing crackling. And that would be somethign a government would not like to happen.

[Rockstar]

A day earlier on Oct. 28, the same plane had experienced similar problems to those seen on the flight that crashed, but managed to resolve them and proceed with the flight safely. Bloomberg reported that’s because a third off-duty pilot who was in the cockpit took the steps needed to stop the plane from engaging in repeated nose-down maneuvers—known in aviation as “runaway trim.” The third pilot’s presence wasn’t noted in Indonesia’s preliminary report on the crash of flight JT610, which attributed the corrective action to the commanding pilot on the Oct. 28 flight.

https://qz.com/1576597/off-duty-pilo...al-flight/amp/

The so-called dead-head pilot on the flight from Bali to Jakarta told the crew to cut power to the motor in the trim system that was driving the nose down, according to the people familiar, part of a checklist that all pilots are required to memorize.
By contrast, the crew on the flight that crashed the next day didn’t know how to respond to the malfunction, said one of the people familiar with the plane’s cockpit voice recorder recovered as part of the investigation. They can be heard checking their quick reference handbook, a summary of how to handle unusual or emergency situations, in the minutes before they crashed, Reuters reported, citing people it didn’t name.

https://qz.com/1576597/off-duty-pilo...al-flight/amp/


A week after the first crash the U.S. FAA sent out a safety alert directing pilots attention to the STAB TRIM thingy ( atleast thats what I think its doing)

https://rgl.faa.gov/Regulatory_and_G..._Emergency.pdf


Using the K.I.S.S. method I will say that as aircraft become more high tech the information and knowledge required to pilot such craft increases dramatically. You had better be prepared to respond to emergency better than what the pilots of the first and second crash did. Taking a nose dive at high speed low level is not the time to start thumbing through the big book of learning how to fly. Pilots need to train more in simulators I guess, otherwise people may die. Unfortunately MCAS worked as it was designed too and it worked flawlessly. It appears to me that flipping just one cutoff switch would have removed MCAS from the equation and put the pilot in charge of the plane. I could be wrong but as I said if the history of airplane crashes is any judge it would lean towards the direction it normally takes, lack of training, qualification process and communication of pertinent advisories and emergency procedure in other words pilot error.

[Skybird]

Again a 737 Max without passengers got into serious troubles and had to emergency-rtb immediately after takeoff in Florida.

Third incident.


If it were the MCAS trim alone, pilots shou,d be informed about it by now when beign allowed to ferry empty planes around. They surely got told by now.

[Skybird]

Other reports say it is not the MCAS trim this time, but an engine problem. But the engines are new as well, the airframe geometry as a whole had to be changed for them, the resulting greater instability, or dysbalance, has to be countered by software again.