[Sutripta]

NTSB report/ recommendation is out.

NYT amongst others reports on it.

Regards
Sutripta

[Jeroen]

Originally Posted by Sutripta

NTSB report/ recommendation is out.

NYT amongst others reports on it.

Pretty much as was expected I would say. It just highlights that Boeing's assumption on how pilots were supposed to react, differ from reality/ Note that the NTSB threads carefully here, still open if the crew should have acted differently.

But also note worthy, there are no formal requirements w or how to validate what those assumptions should have been in the first place. That is a big omission.

They are also highlighting the need for:

Incorporate system diagnostic tools to improve the prioritization of and more clearly present failure indications to pilots to improve the timeliness and effectiveness of their response.

Which we have discussed in the past as well. My insights in alarm annunciation and alarm priorization is a bit outdated. But as far as I am aware it is pretty rudimentary. There are no systems in any cockpit today that would have been able to correlate the various problems that faced these two 737 Max crews. Current alarm prioritization, is, as far as I am aware, is on the actual alarms that shows up on the EICAS (Engine Indicating and crew alerting system).

In this particular situation the stick shaker was going (that is not an EICAS event I think?), erroneous readings of several instruments, (Not all of those what have triggered an EICAS alarm either.

In these circumstances it is very much up to the pilots to determine what the hell is going on. It will take quite some sophisticated automation, including AI/ML to do a robust prioritization of all the various indicators that pilots are facing, which are over and beyond current alarms.

Would be interesting to hear some thoughts from our Pro-Commercial pilots on this one.

I have not come across any material on this more advanced (heavily automated) level of alarm annunciation and prioritization at all. Maybe Airbus is more advanced than Boeing, but from what I have seen/know I do not think so.

When the chips are down, it is up to hardcore pilot skills. It is very rare it comes to that (One of the reason aviation has such a high safety record of course)

Jeroen

Jeroen

[Sutripta]

Originally Posted by Jeroen

Pretty much as was expected I would say.

Expected. Depends on what one was expecting, and how one reads the article! Which is why I included the NYT link.
My take - because a pilot of the calibre of a test pilot could have safely flown the plane does not make every other pilot who fouled up guilty. If only test pilots could be trusted to fly the plane safely, put a certification regime in place which certifies only such pilots for this type of aircraft.

Interpretations from other sources :-
Washington Post

New York Times

Moving away from the 'leftist fake news rags'.

Bloomberg

Forbes

Wall Street Journal

NTSB had a previous paper also.

Regards
Sutripta

PS. Normally I don't post links, rather trying to say what I think. (I should be able to explain what I know. Links without explanations I've assumed are a sign of a coverup - covering up my real lack of understanding. Possibly correct in this case).

[fhdowntheline]

Interesting that NTSB has come out with recommendations for failure alert and pilot response processes, and not particularly commented on the MCAS design issue itself. While I understand that FAA has already done a lot of back-pedalling on this , the solutions still seem very 'band-aided'. The 737 is a 50 year old design. Boeing has been (hopefully no longer) looking at a Max-10 stretch option. How long are the authorities going to continue this grandfathering process? Airbus too has some potential issues with the A320/21 Neos with regard to pitch control, albeit in a limited flight envelope. This greed of deploying more capacity, bigger engines to improve Revenue per-seat-mile has to be questioned .There is only so much you can do with a sub-45 metre long, 3 metre diameter cylinder tube with a sub-40 metre wingspan.

[TSIboy]

Originally Posted by fhdowntheline

The 737 is a 50 year old design. Boeing has been (hopefully no longer) looking at a Max-10 stretch option. How long are the authorities going to continue this grandfathering process? Airbus too has some potential issues with the A320/21 Neos with regard to pitch control, albeit in a limited flight envelope. This greed of deploying more capacity, bigger engines to improve Revenue per-seat-mile has to be questioned.

Boeing could have developed a brand new plane to replace the 737 but they chose to make the MAX out of it. Airbus was hoping they would do excatly that since all they had to compete was 'facelift' the A320.

Both Airbus and Boeing will continue milking these models atleast for the next 4-5 years. The cost of developing a brand new plane is simply too much especially for Boeing given their current suitation.

This cycle will continue until one of them decides to bring a brand new aircraft or there is a new manufacturer good enough to compete. Textbook duopoly.

There is only so much you can do with a sub-45 metre long, 3 metre diameter cylinder tube with a sub-40 metre wingspan.

Infinite possibilities. 737 MAX series, A321 LR & XLR was probably the beginning. A '737 MAX10 ER' or 'A321 XLR Neo' could be coming as well

[Sutripta]

Doing the rounds now
https://www.wsj.com/articles/before-...ds-11569754800

Refers to the Pegasus tanker, based on the 767, not 737. But also implemented (a much better thought out) MCAS.

Regards
Sutripta

[ads11]

Originally Posted by Sutripta

Doing the rounds now
https://www.wsj.com/articles/before-...ds-11569754800

Refers to the Pegasus tanker, based on the 767, not 737. But also implemented (a much better thought out) MCAS.

Regards
Sutripta

That might be about the only good thing to come out of the infernal mess that is the Pegasus programme. Boeing has been struggling with that new tanker for years now and eventually they'll end up being an outside shout in the global tanker market because of it. Rarely too it's a fixed price contract with the USAF so for once, it's the OEM bearing the costs of all the delays so that won't be great combined with the whole headache of the Max saga.

Early on I wondered if the problems of the Max line had parallels with 737 derivatives like the Poseidon but as someone correctly pointed out to me at the time, those military derivatives are all older models of the same line, mainly lacking those giant new engines that precipitated the need for MCAS on the Max line.

[fhdowntheline]

Originally Posted by TSIboy

Boeing could have developed a brand new plane to replace the 737 but they chose to make the MAX out of it. Airbus was hoping they would do excatly that since all they had to compete was 'facelift' the A320.

Both Airbus and Boeing will continue milking these models atleast for the next 4-5 years. The cost of developing a brand new plane is simply too much especially for Boeing given their current suitation.

This cycle will continue until one of them decides to bring a brand new aircraft or there is a new manufacturer good enough to compete. Textbook duopoly.



Infinite possibilities. 737 MAX series, A321 LR & XLR was probably the beginning. A '737 MAX10 ER' or 'A321 XLR Neo' could be coming as well

Cant help but think of our automotive equivalents :TUV300/300Plus Marazzo/XUV300/400(?) /500 etc..What a glamorous lineup

[libranof1987]

Originally Posted by TSIboy

This cycle will continue until one of them decides to bring a brand new aircraft or there is a new manufacturer good enough to compete.

I wouldn't exactly blame Boeing/Airbus. The gestation period for an aircraft runs into decades. I believe they start development only when they have an airline that commits to a strong order book.

Look at what has happened with the A380. Airbus envisaged a certain travel pattern but between their ideation stage and a few years into entering service, the socio-economic patterns have changed to an extent that the A380 is struggling to be relevant. Airbus has admitted they won't recover the investment made into developing the A380.

Although not realistic in the near future, the airline industry may see some headwinds regarding hybrids/electric propulsion?! There's already a thread about flying-shaming due to emissions concerns.

Given the long development cycle and the huge investment ticket size, unlikely that we'll see an "all-new" aircraft. Bombardier has already given up. China is coming up with their own but if they're playing on cost, we don't quite want that for the world!

[Jeroen]

Originally Posted by libranof1987

I wouldn't exactly blame Boeing/Airbus. The gestation period for an aircraft runs into decades. I believe they start development only when they have an airline that commits to a strong order book.

I believe there have been a few cases where aircraft manufacturers took it upon themselves to develop a plane all by themselves before orders. These days not so much, given the huge development cost.

I do not think there is anything inherently wrong with extending a particular model with new versions over the years. Take the 747. First flight in 1970. They are still building new ones, 747-800. The carriers are phasing them out from passengers flights, but most likely we will still see 747s flying for at least another decade as freighters. That means an effective life span of more than 60 years, with about 6 main versions/updates! It is also worth noting that the 747-400 which is the second but last version is the most successful in numbers produced!

Lets be honest, if Boeing had done a proper design job on the MCAS, we would not be having this discussion. Nothing to do with the basic design of the 737 as such and how to extend it.

Boeing could have taken a different approach then introducing MCAS of solving the pitch up tendency, but it would have been more costly.

Jeroen

[Foxbat]

Boeing Engineer Says 737 Max Safety System Was Vetoed Over Cost


“I was willing to stand up for safety and quality, but was unable to actually have an effect in those areas,” Mr. Ewbank said in the complaint, adding, “Boeing management was more concerned with cost and schedule than safety or quality.”

https://www.nytimes.com/2019/10/02/b...gtype=Homepage

[Jeroen]

Originally Posted by Foxbat

Boeing Engineer Says 737 Max Safety System Was Vetoed Over Cost

“I was willing to stand up for safety and quality, but was unable to actually have an effect in those areas,” Mr. Ewbank said in the complaint, adding, “Boeing management was more concerned with cost and schedule than safety or quality.”

He is the umpteenth former Boeing engineer to come forward. Mind you, he did go further than most of the others and lodged a formal complaint. The way I read it, he lodged a complained earlier this year. Which is about 4 years after he left Boeing.

One of the problems I have with these stories is that it is impossible to establish any level of credibility to the person and or his claims. Whether it is about his professional capability or otherwise. Just calling him a senior engineer who worked on cockpit systems does not tell me anything.

If anything it is a shame he did not come forward earlier. Although, of course I understand that can be very difficult. Remains to be seen what the department of justice does with the information and the individual.

This "synthetic airspeed” is a system that is deployed on the 787. It’s origin is more related to problems with unreliable airspeed due to pitot tubes icing up, getting damaged etc. So Boeing came up with what they call synthetic air speed.

Synthetic airspeed is calculated through combining a dual voting AoA sensor input with inertial speed data. Sounds pretty straightforward, pretty easy math. In practice it is a bit more complex. It is supposed to offer more advanced stall protection. And a reliable airspeed obviously.

As this gentleman already eludes to, I too doubt very much if this system would have made any difference on the 737 Max crashes. Air speed (although unreliable) was not a big factor in these crashes). Not sure if the dual voting would have made a difference.

What is interesting to note is that this synthetic airspeed system on the 787 came with a host of problems initially. In 2016 the FAA issued a safety directive. Pilots were cautioned to avoid abrupt control inputs during short periods of unreliable airspeed indicators. There were at least three incidents. The FAA was concerned that pilots might put the plane in a dive which could exceed structural limits of the 787.

One such incident:

https://www.atsb.gov.au/media/577302...-149-final.pdf

I was reading up on some more stuff the other day. If anybody wants to understand a bit more about AoA I recommend this link:

http://www.boeing.com/commercial/aer...ack_story.html

Boeing used to publish their so called aeromagazine. Always very informative, good information. They stopped quite some years ago, but all the old editions are still on line.

Some interesting quotes:

AOA can be used for many indications on the flight deck to improve flight crew awareness of airplane state relative to performance limits. Dedicated AOA indicators have been used on military aircraft for many years, but this form of display has not been used often on commercial airplanes. On Boeing models currently in production, AOA is used to drive stall warning (stick shaker), stall margin information on airspeed indicators, and the pitch limit indicator (PLI) on the primary attitude displays. AOA information is combined with other data and displayed as an integral part of flight deck displays

The U.S. National Transportation Safety Board (NTSB) has recommended visual indication of AOA in commercial airplanes. This indication may take the form of a dedicated AOA indicator or other implementation, such as the PLI.

A dedicated AOA indicator shown on the primary flight display (PFD) recently has been developed in cooperation with airline customers. The new indicator is offered as an option on the 737-600/-700/-800/-900, 767-400, and 777 at this time.

This is an old edition. But as we know, at least on the 737 Max the AoA indicator remained an option

Jeroen

[Sutripta]

Originally Posted by Jeroen

He is the umpteenth former Boeing engineer to come forward. Mind you, he did go further than most of the others and lodged a formal complaint. The way I read it, he lodged a complained earlier this year. Which is about 4 years after he left Boeing.

I think he rejoined Boeing.

One of the problems I have with these stories is that it is impossible to establish any level of credibility to the person and or his claims.

Thus a jury trial and whether the jury believes in the creditability of the person/ witness.

Whether it is about his professional capability or otherwise.

I don't think his professional ability is the issue here. His description of the work environment is.

This "synthetic airspeed” is a system that is deployed on the 787. It’s origin is more related to problems with unreliable airspeed due to pitot tubes icing up, getting damaged etc. So Boeing came up with what they call synthetic air speed.

Synthetic airspeed is calculated through combining a dual voting AoA sensor input with inertial speed data. Sounds pretty straightforward, pretty easy math. In practice it is a bit more complex. It is supposed to offer more advanced stall protection. And a reliable airspeed obviously.

Model based approach. Fairly common provided one knows how the system is supposed to behave inside out. Normally not good enough to take active control/ corrective action. But more than capable of being the machines version of a sanity check.

As this gentleman already eludes to, I too doubt very much if this system would have made any difference on the 737 Max crashes.

Possibly could have handed control over to the pilots saying 'Hmmm, that's odd. Something does not add. Here pilots, you take over' (Anthropomorphising)
But as I said, the real issue (wrt this witness) is his description of how the 737 Max project managers dealt with issues.

Air speed (although unreliable) was not a big factor in these crashes). Not sure if the dual voting would have made a difference.

See previous thoughts.

Regards
Sutripta

[Jeroen]

Originally Posted by Sutripta

I don't think his professional ability is the issue here. His description of the work environment is.

comes down to a very similar thing. He describes something from his own perception / experience. To him, that is his reality. But it does not mean his reality is true. If anything it needs validating.

I have seen people describe the company I work for in a way that I just do not recognise at all. As if we are living in different words.

He describes something that, in the public eye, is the truth, but that does not make it so.

Let's face it, the very fact that he did not report it when it mattered, makes him not very senior in my thinking. Seniority is not about years on the job, or in a particular discipline. Seniority, for me, is among others, how you act in difficult circumstances.

Would be interesting to hear from the managers of this gentleman how did they perceive the working environment. A lot of Boeing managers are (or at least used to be) engineers by trade. With hindsight, did they feel pressured to compromise safety? What were the incentive scheme for managers and engineers?

It would be good to get a far more comprehensive view on how all of this worked. So we need more insights, from a variety of different folks in different roles and responsibilities.

Originally Posted by Sutripta

Model based approach. Fairly common provided one knows how the system is supposed to behave inside out. Normally not good enough to take active control/ corrective action. But more than capable of being the machines version of a sanity check.

AoA is a tricky one at best. It’s not that easy to measure reliably. One thing with the synthetic airspeed is that inertial speed gives you a speed vector (speed/direction), but no side slip. And side slip has a big influence on lift and therefor what the critical AoA might be.

Not always well understood, but you can stall (i.e. exceed critical AoA) on any wing, during all flight regimes.

These days modern AoA sensors tend to be integrated into the pitot tube system as well. Essentially they can derive AoA from differential pressure. At least does away with these very vulnerable mechanical vanes. Does mean that you have to make sure your pitot tube works properly, does not ice up, no mechanical damage, take the cover off on pre-flight check etc. Not sure it the 787 uses this type already.

Jeroen

[Sutripta]

^^^
He has described something. Is it credible? ie. is he a credible witness? To be ascertained by whoever is put in charge to ascertain it.
No need to character assassinate him just yet!

And the synthetic air speed is not really the important part of this story. How it was dealt with is.

And as I've said, the model, and deviations from it provide a sanity check. eg. (From a layman's PoV) - at this point of time with these settings (engine power, flaps, AoA etc) this is where I am (speed, altitude etc), and so next second these will be my readings. So next second are expected behaviour being validated. If not, inform pilots and hand over control to them, and don't do anything drastic.

This narrative is a couple of levels of abstraction above detecting faulty AoA readings. And even that is not the important part of THIS story. It is how management took precedence over engineering.

Regards
Sutripta