Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed
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.

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.
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.

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.
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.

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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
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

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...

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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
They also claim the AoA Disagree alarm was included as an optional extra "inadvertantly".
https://www.bbc.co.uk/news/business-48174797

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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
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.

"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?
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?

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"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?
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.
Last edited by WHBM; 6th May 2019 at 12:14.

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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
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.
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?
Is trimming not a standard practice anymore?
Of course the crew should never had to deal with it by design but it was controllable.

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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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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.
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.

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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.
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.

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RTM Boy :
Absolutely . we see this in other industries and probably this Boeing issue will act as a wake up call for every company that put commercial interests and costs above a safety culture.
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..
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..

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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.

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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.

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.
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.
