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Originally Posted by Smythe
(Post 10462460)
The WSJ is certainly taking on an investigative reporting role in this debacle....very interesting.
This seems to tell a different story that what I have heard before. That MCAS was originally designed to 0.6 degrees, and the test flights showed it needed 2.5 degrees. Now, this says the test pilots didnt know about the 2.5 degrees? The subsequent authority increase to 2.5 degrees could have been kept from the test pilots. They would just demonstrate that the revised MCAS now meets the FAA requirements. |
Originally Posted by fred81
(Post 10462538)
Not necessarily. If it was demonstrated during test flights that with the original MCAS longitudinal stability criteria (i.e. required stick force) were not met, that would have been all the pilots knew at that time. The subsequent authority increase to 2.5 degrees could have been kept from the test pilots. They would just demonstrate that the revised MCAS now meets the FAA requirements. I find it impossible to believe the test pilots would carry out a "test flight", without being told of the changes made and what they should expect. That said I will not be surprised if comment turns out to be correct. |
Originally Posted by Bend alot
(Post 10462619)
When I/we have had issues to deal with (just in maintenance) I/we always inform the pilot/s prior to the flight what we have changed and what we expect they should expect. We expect them to give us feed back after the flight.
I find it impossible to believe the test pilots would carry out a "test flight", without being told of the changes made and what they should expect. That said I will not be surprised if comment turns out to be correct. |
Originally Posted by Bend alot
(Post 10462619)
When I/we have had issues to deal with (just in maintenance) I/we always inform the pilot/s prior to the flight what we have changed and what we expect they should expect. We expect them to give us feed back after the flight.
I find it impossible to believe the test pilots would carry out a "test flight", without being told of the changes made and what they should expect. That said I will not be surprised if comment turns out to be correct. |
Wow.....if anyone was lucky enough to watch 60 Minutes Australia last night, about the MAX and how it was certified....I wonder how Boeing management sleep at night.
Among the damning parts were the AA pilot showing what the "training package" they received was....made no mention of MCAS and how it could override pilot input. Also, clarification of why MCAS is solely reliant on a single AOA sensor.....if Boeing had put redundancy, then they would have been required to do simulator testing before certification....just to clarify here...the people who were interviewed were all in the USA, and representatives of pilot and engineering groups |
Originally Posted by Smythe
(Post 10461650)
Simple fix:
Increase the height of the landing gear (which should have been done 15 years ago) and put the damn motors back where they are supposed to be. That $2 billion it was gonna cost looks pretty cheap right now... Put on new engines and a modern avionics package, a new interior, and smooth out the nose à la 787 (to get rid of all that noise on the flight deck) and voila, you have a new aircraft to compete with AB320Neo. If only... |
Now Boeing admits it was aware of AoA Disagree issues well before the Lion Air disaster from a time before the first sales had been delivered. They now say this issue was to be addressed in a later software update but didn't get round to mentioning it to the FAA until a month after the Lion Air crash.
They also claim the AoA Disagree alarm was included as an optional extra "inadvertantly". https://www.bbc.co.uk/news/business-48174797 |
Originally Posted by KelvinD
(Post 10464257)
Now Boeing admits it was aware of AoA Disagree issues well before the Lion Air disaster from a time before the first sales had been delivered. They now say this issue was to be addressed in a later software update but didn't get round to mentioning it to the FAA until a month after the Lion Air crash.
They also claim the AoA Disagree alarm was included as an optional extra "inadvertantly". https://www.bbc.co.uk/news/business-48174797 When Boeing began delivering its 737 Max to customers in 2017, the company believed that a key cockpit warning light was a standard feature in all of the new jets.But months after the planes were flying, company engineers realized that the warning light worked only on planes whose customers had bought a different, optional indicator.In essence, that meant a safety feature that Boeing thought was standard was actually a premium add-on. |
Originally Posted by GordonR_Cape
(Post 10464268)
Incorrect! That's not what the BBC says, nor the NYT, nor Boeing:
Maybe a bit of SIM training events may have picked this up? Seems Boeing are way behind the 8 ball on the reports released in the last week - Good chance they are also well behind the 8 on training required. Sloppy, sloppy, sloppy is a very big understatement it seems. What news will tomorrow bring? |
Originally Posted by Bend alot
(Post 10464280)
"When Boeing began delivering its 737 Max to customers in 2017, the company believed that a key cockpit warning light was a standard feature in all of the new jets.But months after the planes were flying, company engineers realized that the warning light worked only on planes whose customers had bought a different, optional indicator.In essence, that meant a safety feature that Boeing thought was standard was actually a premium add-on."
Maybe a bit of SIM training events may have picked this up? Seems Boeing are way behind the 8 ball on the reports released in the last week - Good chance they are also well behind the 8 on training required. Sloppy, sloppy, sloppy is a very big understatement it seems. What news will tomorrow bring? In any case there were never, and are still not, enough simulators to actually test the MAX properly, so your question is moot. That goes back to the whole issue of timetable pressures. I don't know how much of this is "news", but rather confirmation of what many suspected months ago. Prolonging the release of information may be justified on legal grounds, but the drip-drip of revelations does nothing to regain confidence. |
When Boeing began delivering its 737 Max to customers in 2017, the company believed that a key cockpit warning light was a standard feature in all of the new jets.But months after the planes were flying, company engineers realized that the warning light worked only on planes whose customers had bought a different, optional indicator.In essence, that meant a safety feature that Boeing thought was standard was actually a premium add-on. Furthermore, this all hangs on the overall management of the programme, and whoever on the sales and marketing side decided to make it a nickel-and-dimed chargeable option that could be discarded to shave pennies off the price. Sticking it on the engineers, who seem to be the one group who are acting professionally in all this, is quite inappropriate. |
Originally Posted by Willoz269
(Post 10463966)
Wow.....if anyone was lucky enough to watch 60 Minutes Australia last night, about the MAX and how it was certified....I wonder how Boeing management sleep at night.
Among the damning parts were the AA pilot showing what the "training package" they received was....made no mention of MCAS and how it could override pilot input. Also, clarification of why MCAS is solely reliant on a single AOA sensor.....if Boeing had put redundancy, then they would have been required to do simulator testing before certification....just to clarify here...the people who were interviewed were all in the USA, and representatives of pilot and engineering groups Is trimming not a standard practice anymore? |
Charging for features that are pin changes or already included in the hardware has been standard Boeing practice for a while. The Ryanair 738s has black and white FMCs as that was what they paid for despite the units being colour screened, as was obvious from the power up screen. Similar issue with some performance data - Boeing have it, but you can only have it if you at for it. |
It probably didn't mention how MCAS could override pilot input because MCAS could not override pilot input. It is the other way around any trim input by the flight crew would (and did) override MCAS. That is how the penultimate Lion Air flight continued to a safe landing and how the first 6 minutes or so of the Lion Air crash flight proceeded. It was only when the PM on that flight took over and ceased to trim back to unloaded just 'blipped' the trim to stop MCAS that nose down trim increased to uncontrollable levels. Is trimming not a standard practice anymore? Of course the crew should never had to deal with it by design but it was controllable. |
Originally Posted by Icarus2001
(Post 10464991)
Exactly. This is the crux of the issue.
Of course the crew should never had to deal with it by design but it was controllable. Ask yourself; mmm, is this a good idea? I mean really, is it? Anyone with the slightest understanding of safety and risk management will know you must design problems out from the very start, not try to overcome them with additional systems and procedures that add layers of complexity and increased room for error and so increasing risk - and catastrophic risk at that. To have non-redundant sensor input tells you what about the design. Safety first is it? I know forums are full of mischief makers, but this constant "oh the crew could have staved the situation" narrative is a total diversion from the 'crux' of the issue. It's almost as if you forget that hundreds of PAX and crew have died appalling deaths as a result of flight crew being put in a position they should never ever have been put in. The problem is the big picture, not the setting of trim. |
Absolutely. The technical 'fix' to this problem is probably relatively simple but it is becoming more clear that such a fix would have brought commercial irritation.
Shuffling risk - inexcusable in modern aviation. Whilst I'm at it, trim runaways. In non-MCAS aircraft, how likely was a trim runaway, how often did it happen and, if it ever did, how often was it successfully handled? Ask the same questions of an MCAS aircraft. My point is that if you increase the likelihood of an event (trim runaway) you are also increasing the likelihood that your last line of defence (pilots) may get it wrong, especially if you don't reinforce specific training. MCAS increased the risk of a catastrophic trim runaway and where was the training? The statistics, if ever divulged, will be interesting. |
Cows,
Certainly when I did the trim runaway in the sim, the TRE pointed out that the condition that would cause this was both the trim switches failing independently, at exactly the same time. The twin switches provide excellent redundancy, and I'd bet that there has never been a trim runaway performed for real, ever. |
RTM Boy :
The problem is the big picture, not the setting of trim. The passage in the recent Seattle Times and the drawing on how DER and AR worked was an highlighter : the AR had to submit their comments to management before going to the FAA was made to be allowing exactly this : making sure management commercial views and schedule were not compromised. This is for me the real issue, MCAS or trim are just the by-products of this philosophy.. |
Originally Posted by Cows getting bigger
(Post 10465185)
Whilst I'm at it, trim runaways. In non-MCAS aircraft, how likely was a trim runaway, how often did it happen and, if it ever did, how often was it successfully handled? Ask the same questions of an MCAS aircraft. My point is that if you increase the likelihood of an event (trim runaway) you are also increasing the likelihood that your last line of defence (pilots) may get it wrong, especially if you don't reinforce specific training. MCAS increased the risk of a catastrophic trim runaway and where was the training? The statistics, if ever divulged, will be interesting. |
Thanks 737 driver. It was a bit of a rhetorical question used to highlight that if we’re now in the realms of ‘more’ trim runaways, we’ve weakened one of the layers of safety and, in an ideal world, need to reinforce the safety system somewhere else to maintain the same level of safety. |
Originally Posted by GordonR_Cape
(Post 10464300)
The training/testing problem is an extension of the software fault tree analysis problem, and the consistent shifting of risk. If you aren't "aware" that AOA is a critical parameter, you won't include testing for AOA disagree, or MCAS, or anything else...
In any case there were never, and are still not, enough simulators to actually test the MAX properly, so your question is moot. That goes back to the whole issue of timetable pressures. I don't know how much of this is "news", but rather confirmation of what many suspected months ago. Prolonging the release of information may be justified on legal grounds, but the drip-drip of revelations does nothing to regain confidence. As claimed by a whistle blower working with the FBI. The single AoA for MCAS to obtain data was intentional move by Boeing. The whistle blower claims that using both AoA vanes would lead to the FAA to require extra training in the simulator. This was not an option for Boeing as the sales was dependant on minor training. Boeing sold the MAX on it NOT requiring simulator training. That is the reason there are "not enough" simulators. Had Boeing used both AoA sensors and the FAA did then decide that MAX did require a similar training event, we would have MANY more simulators than we do today. Not enough simulators is a direct result of Boeing's words to customers. Right now Boeing is trying to get everyone including NASA to put pressure on the FAA to say "no simulator training is required" MCAS is good now, even if originally we would have called for simulator training. In my opinion FAA should throw out the MAX certification and redo it with direct oversight regardless of how long it takes and what training is then decided. Yes it will also hurt airlines around the World but if it looks too good to be true - someone is taking a short cut! and the airlines were/are happy to look away. |
Originally Posted by RTM Boy
(Post 10465168)
Very, very, easy to say with weeks to think about it from the comfort of your armchair. The 'crux' of the issue is that today, with all the technology actually available and design and testing regimes that should be adhered to, no MUST be adhered to, the MAX design should never have got off the CAD drawing board. Boeing should have gone to a brand new design, but for business reasons we are all now well aware of, they decided not to. It's too easy to let the detail of procedures and switches and trimming and Christ knows what else get in the way of seeing things for what they are; look at the big picture; the very fact that systems like MCAS are necessary at all tells you all you need to know about the compromised design of the MAX.
Ask yourself; mmm, is this a good idea? I mean really, is it? Anyone with the slightest understanding of safety and risk management will know you must design problems out from the very start, not try to overcome them with additional systems and procedures that add layers of complexity and increased room for error and so increasing risk - and catastrophic risk at that. To have non-redundant sensor input tells you what about the design. Safety first is it? I know forums are full of mischief makers, but this constant "oh the crew could have staved the situation" narrative is a total diversion from the 'crux' of the issue. It's almost as if you forget that hundreds of PAX and crew have died appalling deaths as a result of flight crew being put in a position they should never ever have been put in. The problem is the big picture, not the setting of trim. Thank you RTM Boy. |
Originally Posted by RTM Boy
(Post 10465168)
...
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Originally Posted by RTM Boy
(Post 10465168)
Very, very, easy to say with weeks to think about it from the comfort of your armchair. The 'crux' of the issue is that today, with all the technology actually available and design and testing regimes that should be adhered to, no MUST be adhered to, the MAX design should never have got off the CAD drawing board. Boeing should have gone to a brand new design, but for business reasons we are all now well aware of, they decided not to. It's too easy to let the detail of procedures and switches and trimming and Christ knows what else get in the way of seeing things for what they are; look at the big picture; the very fact that systems like MCAS are necessary at all tells you all you need to know about the compromised design of the MAX.
Ask yourself; mmm, is this a good idea? I mean really, is it? Anyone with the slightest understanding of safety and risk management will know you must design problems out from the very start, not try to overcome them with additional systems and procedures that add layers of complexity and increased room for error and so increasing risk - and catastrophic risk at that. To have non-redundant sensor input tells you what about the design. Safety first is it? I know forums are full of mischief makers, but this constant "oh the crew could have staved the situation" narrative is a total diversion from the 'crux' of the issue. It's almost as if you forget that hundreds of PAX and crew have died appalling deaths as a result of flight crew being put in a position they should never ever have been put in. The problem is the big picture, not the setting of trim. .
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Well said, RTM Boy. |
Here is a good recent article on Boeing certification problems:
https://www.seattletimes.com/busines...uding-737-max/ Fly SAFE! God Bless, and Namaste... |
Boeing presumably expect the MAX to have a 20 year in service life and the fact that this would involve a 1960s master caution system and associated warning lights as the main interface between pilots and system malfunctions to persist into the 2040s is almost unbelievable. Flightcrew training has become increasingly systemised through CBT and many modern pilots started their flying career with Microsoft rather than in a tiger moth or a C150 and they are now far more SOP and rule based in their approach to problem solving compared to when the original B737 was designed and an EICAS or ECAM is central to all modern flightdecks in order to assist with non normal ops. Crews in future years will either be flying modern Airbus or Boeing designs or if selected for the Max, a 1960s throwback. In my view, if the crews of the 21st century do not have an adequate warning system providing full systems information, then the aircraft is not fit for purpose. |
The certification flow chart in the Seattle times article (post 906) is simply incredible. Anyone in the FAA who thought this was acceptable is in the wrong job. |
Thread suspended until there is actual new information. Angels dancing on the head of too small a pin.
Rob |
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