Boeing 737MAX Grounded Worldwide Q4 2019, Production suspended

BravoOne · Thu Oct 31, 2019 8:16 pm

I seriously doubt that Mark Forkner will be the beneficiary of any money coming from this suit and that's even assuming that the SWA pilots prevail. Sounds like he cut himself a deal beyond the traditional new hire SWA entry F/O job. If by chance he is paying for his legal team he is probably so far under water that little if anything will make him whole again. Maybe SAWPA should create a Go Fund Me package for the guy. I feel badly for him, but he has no one but himself to blame at this hour.

PW100 · Thu Oct 31, 2019 8:17 pm

planecane wrote:
shmerik wrote:
The more info that comes out about what Boeing knew about MCAS the less it all makes sense to me. I know this may be seen as hyperbole as some and it's just pure speculation as we don't have access to test flight info, but at this point I wouldn't be surprised if the massive increase in authority came from discovering more extreme behavior on approach to stall than just slight stick lightening.

For the 100th time (and this has been reported in multiple articles), the increase in authority came because they discovered that MCAS was needed in low speed situations when it was originally designed for high speed situations. In the low speed situation, the stabilizer needs to move more in order to create the same force.
Look out the window at the ailerons on your next flight. Shortly after takeoff or when close to landing they deflect a lot and the bank angle barely changes. At cruise, the movement is almost imperceptible but the bank angle changes significantly. It is the exact same reason.

JTAR Final Report wrote:
Observation O3.4-B: Extension of MCAS to the low-speed and 1g environment during the flight program WAS DUE TO UNACCEPTABLE STALL CHARACTERISTICS WITH STS ONLY. The possibility of a pitch-up tendency during approach to stall was identified for the flaps-up configuration prior to the implementation of MCAS.

Finding F3.5-C: The JATR team considers that the STS/MCAS and EFS functions could be considered as stall identification systems or stall protection systems, depending on the natural (unaugmented) stall characteristics of the aircraft.

PW100 · Thu Oct 31, 2019 8:27 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:
I'll ignore JT for now as neither of us could say for sure what would have happened - we just have our beliefs.
ET is a lot easier though to say they would not have saved an NG with runaway trim either.
After MCAS had activated a few times on ET and they turned off the trim switches they would have been at the same condition as runaway trim on an NG with the Electric trim off - yet they did not save it.
Failure to put the plane back in trim before hitting switches/Failure to control airspeed/ possibly not being familiar with the backup trim system (same as on the NG), manual trim system possibly not working due to excessive speed would have caused them to crash an NG as well - for if they had turned the switches back on an NG the runaway pitch trim would have resumed resulting in putting them in the ground faster as it would have been one continuous pitch change motion.
They would not have saved an NG either.

I'm calling BS.

You are totally ignoring that any crew could fall into this trap as the run-away MCAS was camouflaged by all sort of alerts (like Stick Shaker/Stall Warning/Master Caution Ant-Ice/Unreliable Air Speed), and there was no clue (no EICAS) to help the crew prioritize the Christmas tree light-up they were being presented.
Also, as I have argued before I'm not convinced (at this stage) that leaving the aircraft in untrimmed condition when they hit the switches was by their choice. All four crew up-trim actions (after MCAS run-away) stopped at exactly the same point. Even if you wanted to do that on purpose you probably would not succeed in that.

I'd expect that between 25% and 75% of decently trained western crews would also have crashed, for above mentioned reasons.

So if you were in an NG that had real runaway trim (you would have had to hit both switches to turn off electric trim entirely and stop the runaway) and you are way out of trim over Vmo with AT TOGA engaged possibly making it difficult to use the manual trim wheels (that fact is not established yet) what would you do to recover?

What is the first thing you would do?

You forgot to add Stick Shaker/Stall Warning/Master Caution Ant-Ice/Unreliable Air Speed warnings/alerts. Throw in those factors, and you'd likely crash your NG if you are below FL100, no matter what checklist you pull out.

PW100 · Thu Oct 31, 2019 8:33 pm

sgrow787 wrote:
XRAYretired wrote:
Another Herculean analysis from Peter Lemme.

"Observation O6.9-H: Boeing concluded that multiple erroneous MCAS activations were not worse than a single erroneous activation, based on the assumption that the crew would return the aircraft to a trimmed state (consistent with AC 25-7C guidance) following each activation."

It would seem to me, a non-pilot, that the increase in airspeed that comes with MCAS AND action, would result in the pilot needing less pitch correction to return to stable flight. Would this explain the lack of return of the stab trim all the way to what it was pre-AND?

BTW, from what I can tell from the DFDR plots, the authority from the eTrim is only 0.15 deg/sec, which is about 40% less than the 0.27 deg/sec (2.5 [deg/cyc] / 9 [sec/cyc]) from MCAS, which is significant.

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

ikramerica · Thu Oct 31, 2019 8:37 pm

seahawk wrote:
morrisond wrote:
dtw2hyd wrote:

Even though the captain was fighting MCAS thru trim switch, it was a losing battle as with every MCAS-ANU iteration MCAS was gaining. At some point, it reached the point of no return.

No the Captain was doing a great Job fulling offsetting MCAS on average 22 times - it's only when the FO took over that the battle was lost - in 2-3 instances of MCAS activation as it seems like he did not know who to use the trim properly and was not told about it by the Captain.

And if you have to trim up 22 times, one can expect a reasonably skilled crew to come up with the runaway trim checklist and disable the system. The crews showed unacceptable bad crew resource management and lacked basic flying skills, which must be seen as the final factors for the crash.

That’s my sticking point too. You can speak of 4 seconds reaction or 8 seconds etc. to figure out what’s wrong, but then you get to 22 instances and still no disabling of the trim, and you start to wonder.

As many have pointed out, flying shouldn’t be an IQ test, and the MAX design made it into one, and that’s bad design.

But at the same time, you want to sit in either seat at the front of a commercial aircraft, you better know your memory items. You better know how to hand fly your equipment. You better know how to turn automation off. It would be a different discussion if the pilots did all the right things (or even 1/2) and they couldn’t recover. But that’s not what happened.

Another question I have is about the previous flight. Were the two pilots known as exceptional? Did they always pass all their training at 100% perfection? Did the report get into their history at all? We know the FO of the final flight was deficient but somehow allowed to be in the seat, but what of the previous crew that figured it out and hand flew the plane safely to the destination?

morrisond · Thu Oct 31, 2019 8:38 pm

PW100 wrote:
morrisond wrote:
PW100 wrote:

I'm calling BS.

You are totally ignoring that any crew could fall into this trap as the run-away MCAS was camouflaged by all sort of alerts (like Stick Shaker/Stall Warning/Master Caution Ant-Ice/Unreliable Air Speed), and there was no clue (no EICAS) to help the crew prioritize the Christmas tree light-up they were being presented.
Also, as I have argued before I'm not convinced (at this stage) that leaving the aircraft in untrimmed condition when they hit the switches was by their choice. All four crew up-trim actions (after MCAS run-away) stopped at exactly the same point. Even if you wanted to do that on purpose you probably would not succeed in that.

I'd expect that between 25% and 75% of decently trained western crews would also have crashed, for above mentioned reasons.

So if you were in an NG that had real runaway trim (you would have had to hit both switches to turn off electric trim entirely and stop the runaway) and you are way out of trim over Vmo with AT TOGA engaged possibly making it difficult to use the manual trim wheels (that fact is not established yet) what would you do to recover?

What is the first thing you would do?

You forgot to add Stick Shaker/Stall Warning/Master Caution Ant-Ice/Unreliable Air Speed warnings/alerts. Throw in those factors, and you'd likely crash your NG if you are below FL100, no matter what checklist you pull out.

So I take it you are retracting you calling BS on me as they would have crashed the NG as well as they didn't actually have a real grasp of how to control the plane without the AP. Just like the Captain of ET409 who crashed an NG while trying to fly manually who went through ET training at about the same time as the ET302 Captain.

BTW - the answer was - disconnect the AT and get control of the airspeed so the manual trim wheel becomes usuable. You would have had to do that on an NG as well.

BravoOne · Thu Oct 31, 2019 8:38 pm

PW100 wrote:
sgrow787 wrote:
XRAYretired wrote:
Another Herculean analysis from Peter Lemme.

"Observation O6.9-H: Boeing concluded that multiple erroneous MCAS activations were not worse than a single erroneous activation, based on the assumption that the crew would return the aircraft to a trimmed state (consistent with AC 25-7C guidance) following each activation."

It would seem to me, a non-pilot, that the increase in airspeed that comes with MCAS AND action, would result in the pilot needing less pitch correction to return to stable flight. Would this explain the lack of return of the stab trim all the way to what it was pre-AND?

BTW, from what I can tell from the DFDR plots, the authority from the eTrim is only 0.15 deg/sec, which is about 40% less than the 0.27 deg/sec (2.5 [deg/cyc] / 9 [sec/cyc]) from MCAS, which is significant.

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

True and you may recall that the 727 had a separate stab trim toggle on the pedestal just meant for high speed trim inputs. Seldom used, but there none the less.

starrion · Thu Oct 31, 2019 8:40 pm

The bigger question right now is 'Where is the fix'? October has come and gone and there is no fix submitted. Is Boeing quietly going to drop a press release of Return to Flight 2020?

morrisond · Thu Oct 31, 2019 8:44 pm

PW100 wrote:
sgrow787 wrote:
XRAYretired wrote:
Another Herculean analysis from Peter Lemme.

"Observation O6.9-H: Boeing concluded that multiple erroneous MCAS activations were not worse than a single erroneous activation, based on the assumption that the crew would return the aircraft to a trimmed state (consistent with AC 25-7C guidance) following each activation."

It would seem to me, a non-pilot, that the increase in airspeed that comes with MCAS AND action, would result in the pilot needing less pitch correction to return to stable flight. Would this explain the lack of return of the stab trim all the way to what it was pre-AND?

BTW, from what I can tell from the DFDR plots, the authority from the eTrim is only 0.15 deg/sec, which is about 40% less than the 0.27 deg/sec (2.5 [deg/cyc] / 9 [sec/cyc]) from MCAS, which is significant.

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

PW100 · Thu Oct 31, 2019 8:49 pm

Revelation wrote:
DenverTed wrote:
Revelation wrote:

It also points out that Forkner is now a WN pilot and member of the SWAPA pilot's union, the same union that is suing Boeing for $100M+ for lost wages, some of which presumably would be paid out to Forkner should they win the law suit. Ironic, eh?

That's some Jedi stuff for sure.

Meanwhile in the US, the news cycle for the CEO hearings has passed, now the impeachment drama has all the eyeballs with no indication whatsoever that the ungrounding timeline has shifted.

MCAS was initially designed for the high speed winding turn. The part of the flight envelope a crew would normally never be expected to see. This was Forkner’s main justification to have MCAS reference removed from the pilot operating manual (FCOM). Forkner then realized that he had lied (unknowingly) to the FAA, as he was not included in the memo that MCAS was extended to the low speed regime.

What I wanted to hear from Muilenburg is whether Boeing got back to the FAA once they (Forkner, and Gustavsson) realized that they had lied (unknowingly) to the FAA. I mean, lying unknowingly is not that bad, things do change during development and testing phases. But not forwarding the newly gained knowledge, and associated reasons for not mentioning MCAS in the FCOM would be the real bad thing.

PW100 · Thu Oct 31, 2019 8:52 pm

morrisond wrote:
PW100 wrote:
sgrow787 wrote:

"Observation O6.9-H: Boeing concluded that multiple erroneous MCAS activations were not worse than a single erroneous activation, based on the assumption that the crew would return the aircraft to a trimmed state (consistent with AC 25-7C guidance) following each activation."

It would seem to me, a non-pilot, that the increase in airspeed that comes with MCAS AND action, would result in the pilot needing less pitch correction to return to stable flight. Would this explain the lack of return of the stab trim all the way to what it was pre-AND?

BTW, from what I can tell from the DFDR plots, the authority from the eTrim is only 0.15 deg/sec, which is about 40% less than the 0.27 deg/sec (2.5 [deg/cyc] / 9 [sec/cyc]) from MCAS, which is significant.

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

So we now have conflicting, opposing info how a decently trained pilot should handle the trim at high speed. Great. Carry on throwing the crew under the bus.

morrisond · Thu Oct 31, 2019 8:53 pm

PW100 wrote:
Revelation wrote:
DenverTed wrote:

That's some Jedi stuff for sure.

Meanwhile in the US, the news cycle for the CEO hearings has passed, now the impeachment drama has all the eyeballs with no indication whatsoever that the ungrounding timeline has shifted.

MCAS was initially designed for the high speed winding turn. The part of the flight envelope a crew would normally never be expected to see. This was Forkner’s main justification to have MCAS reference removed from the pilot operating manual (FCOM). Forkner then realized that he had lied (unknowingly) to the FAA, as he was not included in the memo that MCAS was extended to the low speed regime.

What I wanted to hear from Muilenburg is whether Boeing got back to the FAA once they (Forkner, and Gustavsson) realized that they had lied (unknowingly) to the FAA. I mean, lying unknowingly is not that bad, things do change during development and testing phases. But not forwarding the newly gained knowledge, and associated reasons for not mentioning MCAS in the FCOM would be the real bad thing.

As part of his testimony he did say the FAA knew that they had extended it to the low speed regime as well.

PW100 · Thu Oct 31, 2019 8:56 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:

So if you were in an NG that had real runaway trim (you would have had to hit both switches to turn off electric trim entirely and stop the runaway) and you are way out of trim over Vmo with AT TOGA engaged possibly making it difficult to use the manual trim wheels (that fact is not established yet) what would you do to recover?

What is the first thing you would do?

You forgot to add Stick Shaker/Stall Warning/Master Caution Ant-Ice/Unreliable Air Speed warnings/alerts. Throw in those factors, and you'd likely crash your NG if you are below FL100, no matter what checklist you pull out.

So I take it you are retracting you calling BS on me as they would have crashed the NG as well as they didn't actually have a real grasp of how to control the plane without the AP. Just like the Captain of ET409 who crashed an NG while trying to fly manually who went through ET training at about the same time as the ET302 Captain.

BTW - the answer was - disconnect the AT and get control of the airspeed so the manual trim wheel becomes usuable. You would have had to do that on an NG as well.

ET speed was OK right up until MCAS run-away. If run-away trim would hit NG at that very same point, the result would not have been different. No matter what crew.

PW100 · Thu Oct 31, 2019 8:57 pm

morrisond wrote:
PW100 wrote:
Revelation wrote:
Meanwhile in the US, the news cycle for the CEO hearings has passed, now the impeachment drama has all the eyeballs with no indication whatsoever that the ungrounding timeline has shifted.

MCAS was initially designed for the high speed winding turn. The part of the flight envelope a crew would normally never be expected to see. This was Forkner’s main justification to have MCAS reference removed from the pilot operating manual (FCOM). Forkner then realized that he had lied (unknowingly) to the FAA, as he was not included in the memo that MCAS was extended to the low speed regime.

What I wanted to hear from Muilenburg is whether Boeing got back to the FAA once they (Forkner, and Gustavsson) realized that they had lied (unknowingly) to the FAA. I mean, lying unknowingly is not that bad, things do change during development and testing phases. But not forwarding the newly gained knowledge, and associated reasons for not mentioning MCAS in the FCOM would be the real bad thing.

As part of his testimony he did say the FAA knew that they had extended it to the low speed regime as well.

I'm talking about the folks who were in charge of approving FCOM contents. Were they informed?

PW100 · Thu Oct 31, 2019 9:03 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:

No - it was the First Officer who didn't know how to offset the Yoke forces with electric trim who was pulling with 105 lbs of force - he did not have a stick shaker going off on his side.

Do you seriously think that the FO did not know how to offset yoke forces, never used electrical trim before?
If you really believe that, then I find it easy to understand why your posts continue to focus on how the crew basically crashed the plane.

The KNKT investigators pointed that out. He was cited repeatedly in SIM training for being behind the aircraft and not being able to control it during manual flight.

It wasn't me making that up.

I did not read he did not know how to use manual electric trimming (or, didn't know how to offset the Yoke forces with electric trim *your words, not mine*). Perhaps you can quote that part of the report for me. Otherwise, yes you are making things up.

PW100 · Thu Oct 31, 2019 9:05 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:
I don't doubt it all - that's why "Global training standards need to improve Worldwide" this is not only a third world training problem. It needs to be fixed with regulation - just like Boeing and the FAA need to be fixed.

Just hopefully on average on the big western airlines the average competency is better and chance doesn't give you a bad crew and the holes in the swiss cheese don't line up when something goes wrong.

“Global training standards Worldwide” are reasonably fine. Could they be improved? Sure. But accident rates have never been better than today, if we leave the Max out of the equation.

The accident rates being lower doesn't necessarily mean the crews are getting better - it just basically means the systems are getting better and there are having less catastrophic failures and instances where Pilots are having to show they know what they are doing is fewer than ever thankfully.

I did not say they are getting better. I'm saying that Global training standards Worldwide” are reasonably fine.

But I'll give it to you that reasonably fine is not good enough for the Max (equipped with MCAS 1.0), not by a loooong mile.

shmerik · Thu Oct 31, 2019 9:08 pm

PW100 wrote:
morrisond wrote:
PW100 wrote:

You forgot to add Stick Shaker/Stall Warning/Master Caution Ant-Ice/Unreliable Air Speed warnings/alerts. Throw in those factors, and you'd likely crash your NG if you are below FL100, no matter what checklist you pull out.

So I take it you are retracting you calling BS on me as they would have crashed the NG as well as they didn't actually have a real grasp of how to control the plane without the AP. Just like the Captain of ET409 who crashed an NG while trying to fly manually who went through ET training at about the same time as the ET302 Captain.

BTW - the answer was - disconnect the AT and get control of the airspeed so the manual trim wheel becomes usuable. You would have had to do that on an NG as well.

ET speed was OK right up until MCAS run-away. If run-away trim would hit NG at that very same point, the result would not have been different. No matter what crew.

It looks like speed stayed at Vmo and they were climbing still for almost a minute (~40-50 seconds) after presumably flipping the stab trim cutout (going by the point where the pilot's ANU trim stops).

Is the theory that after that time the control column wore them out or what? Around 05:41:15 is where their pitch drops significantly and then the plane speeds up even further.

shmerik · Thu Oct 31, 2019 9:21 pm

Actually the more I look at the graphs the more confused I'm getting. It looks like they were having more success at climbing even as MCAS was trimming down than after shutting off stab trim.

Compare the pitch attitude display from 05:41:00 - 05:41:15 shortly after flipping the switches to from 05:41:15 - 05:43:15. Looks like things were pretty stable and then there was a loss of control around 05:41:15, is this because of too much speed or what?

Any ideas?

747megatop · Thu Oct 31, 2019 9:28 pm

asdf wrote:
Northpole wrote:
I read somewhere in Swedish newspaper that Kevin McAllister has been sacked from Boeing

seems like ...

https://www.streetinsider.com/Corporate ... 34229.html

Boeing (BA) Announces Stan Deal to Succeed Kevin McAllister as CEO of Boeing Commercial Airplanes

Looks like STAN got a very good DEAL at Boeing. Muilenberg is saying Stan DEAL with MAX please.

XRAYretired · Thu Oct 31, 2019 10:05 pm

shmerik wrote:
Actually the more I look at the graphs the more confused I'm getting. It looks like they were having more success at climbing even as MCAS was trimming down than after shutting off stab trim.

Compare the pitch attitude display from 05:41:00 - 05:41:15 shortly after flipping the switches to from 05:41:15 - 05:43:15. Looks like things were pretty stable and then there was a loss of control around 05:41:15, is this because of too much speed or what?

Any ideas?

https://www.satcom.guru/2019/04/what-ha ... et302.html

Have a look at some detailed analysis.

Ray

StTim · Thu Oct 31, 2019 10:14 pm

Do you know what - I actually don't care if the crew could have saved the plane. They should never have been put in that position. End of - period.

This saga started with terrible design and ended with pilots fighting for their - and their passengers lives.

I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

shmerik · Thu Oct 31, 2019 10:24 pm

XRAYretired wrote:
shmerik wrote:
Actually the more I look at the graphs the more confused I'm getting. It looks like they were having more success at climbing even as MCAS was trimming down than after shutting off stab trim.

Compare the pitch attitude display from 05:41:00 - 05:41:15 shortly after flipping the switches to from 05:41:15 - 05:43:15. Looks like things were pretty stable and then there was a loss of control around 05:41:15, is this because of too much speed or what?

Any ideas?

https://www.satcom.guru/2019/04/what-ha ... et302.html

Have a look at some detailed analysis.

Ray

Thanks, so it seems that at that point they must have been exerting themselves significantly to keep the nose up

Chemist · Thu Oct 31, 2019 10:25 pm

StTim wrote:
Do you know what - I actually don't care if the crew could have saved the plane. They should never have been put in that position. End of - period.

This saga started with terrible design and ended with pilots fighting for their - and their passengers lives.

I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

I agree with your statements. But do you really think an FO that doesn't use trim and can't find checklists they are supposed to have memorized is reasonably well trained?

planecane · Thu Oct 31, 2019 10:31 pm

sgrow787 wrote:
planecane wrote:
For the 100th time (and this has been reported in multiple articles), the increase in authority came because they discovered that MCAS was needed in low speed situations ...

But common sense says they would have maintained the high-speed authority at 0.6 deg/cyc. In fact, it may be the case that they failed to keep that in the design, or they kept it in the design, but failed to implement it correctly, although we know they implemented it correctly with MCAS 0.0 G+AOA design, so that argument doesn't hold water.

I don't recall the timeline that they became aware of the low-speed issue and MCAS solution/authority change. If it was early enough before certification (more than a year I would think), then it's hard to argue they ran out of time to get that one right, leading one to believe they didn't want the new solution to veer far from the 0.6 deg/cyc version they submitted previously to the FAA (ie, let's just change the number rather than have a new paragraph explaining the logic behind an authority change - if airspeed indicates low speed, use 2.5, if high speed, use 0.6).

No dispute that would have been the right way to design it. The post I replied to was suggesting that the increase in authority was because the original 0.6 units weren't enough to solve the original issue.

StTim · Thu Oct 31, 2019 10:56 pm

Chemist wrote:
StTim wrote:
Do you know what - I actually don't care if the crew could have saved the plane. They should never have been put in that position. End of - period.

This saga started with terrible design and ended with pilots fighting for their - and their passengers lives.

I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

I agree with your statements. But do you really think an FO that doesn't use trim and can't find checklists they are supposed to have memorized is reasonably well trained?

But remember there was only a but of differences training for the crews who flew the MAX over the NG and in the AoA setting off the MCAS they were in uncharted territory that they had not been trained for.

AABusDrvr · Thu Oct 31, 2019 10:56 pm

PW100 wrote:
sgrow787 wrote:
XRAYretired wrote:
Another Herculean analysis from Peter Lemme.

"Observation O6.9-H: Boeing concluded that multiple erroneous MCAS activations were not worse than a single erroneous activation, based on the assumption that the crew would return the aircraft to a trimmed state (consistent with AC 25-7C guidance) following each activation."

It would seem to me, a non-pilot, that the increase in airspeed that comes with MCAS AND action, would result in the pilot needing less pitch correction to return to stable flight. Would this explain the lack of return of the stab trim all the way to what it was pre-AND?

BTW, from what I can tell from the DFDR plots, the authority from the eTrim is only 0.15 deg/sec, which is about 40% less than the 0.27 deg/sec (2.5 [deg/cyc] / 9 [sec/cyc]) from MCAS, which is significant.

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

In normal operations, you usually make small trim inputs. But there are times when you have to make large trim inputs, like a takeoff at light weight, when you accelerate and are making an 80 knot or more speed change. Trimming is all done by feel, if you need a little, use a little, if you need more, use more. But I can guarantee you, if the airplane was so far out of trim, that I couldn't get the nose up, I'd bury my thumb into the switch, and hold it until I had what I needed.

PW100 wrote:
morrisond wrote:
PW100 wrote:

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

So we now have conflicting, opposing info how a decently trained pilot should handle the trim at high speed. Great. Carry on throwing the crew under the bus.

There isn't any conflicting information at all. You do what you need to do, to maintain control of the airplane. Whatever that may be.

morrisond · Fri Nov 01, 2019 12:33 am

StTim wrote:
Do you know what - I actually don't care if the crew could have saved the plane. They should never have been put in that position. End of - period.

This saga started with terrible design and ended with pilots fighting for their - and their passengers lives.

I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

You need to read the JT crash final report - they were not even close to average in terms of ability.

morrisond · Fri Nov 01, 2019 12:34 am

shmerik wrote:
XRAYretired wrote:
shmerik wrote:
Actually the more I look at the graphs the more confused I'm getting. It looks like they were having more success at climbing even as MCAS was trimming down than after shutting off stab trim.

Compare the pitch attitude display from 05:41:00 - 05:41:15 shortly after flipping the switches to from 05:41:15 - 05:43:15. Looks like things were pretty stable and then there was a loss of control around 05:41:15, is this because of too much speed or what?

Any ideas?

https://www.satcom.guru/2019/04/what-ha ... et302.html

Have a look at some detailed analysis.

Ray

Thanks, so it seems that at that point they must have been exerting themselves significantly to keep the nose up

Yes they would have been the JT FO was exerting about 105 lbs of force - I think in the article Ray quoted the certification basis allows up to 125lbs if I read it correctly

dtw2hyd · Fri Nov 01, 2019 12:51 am

morrisond wrote:

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

Have you read the report? FO used ANU trim six times.

23:30:48 - Captain asked FO to take control (Pitch Trim 4.8)
23:30:49 - FO ANU trim for 3 seconds
23:30:52 - FO - I have control
23:31:00 - Automatic trim for 8 seconds (Pitch Trim from 5.4 to 3.4)
23:31:08 - FO - ANU trim for 1 second (Pitch 3.5)
23:31:15 - MCAS for 3 seconds
23:31:17 - FO - ANU trim for 1 second (Pitch 2.9, back pressure 65 lbs)
23:31:19 - FO - ANU trim for 4 seconds (Pitch 3.4)
23:31:27 - MCAS for 8 seconds (Pitch 1.8, back pressure 82 lbs)
23:31:37 - FO - ANU trim for 2 seconds (Pitch 1.3)
23:31:43 - MCAS for 4 seconds (Pitch 0.3, back pressure 93 lbs)
23:31:46 - FO - ANU trim for 2 seconds (Captain PFD 3200ft, FO PFD 3600ft, rate of descent 10,000 ft/sec)
23:31:51 - TERRAIN and SINK RATE warnings
23:31:53 - MCAS activated until recording stopped. This must be a proud moment for the software team.

par13del · Fri Nov 01, 2019 1:43 am

ikramerica wrote:
Another question I have is about the previous flight. Were the two pilots known as exceptional? Did they always pass all their training at 100% perfection? Did the report get into their history at all? We know the FO of the final flight was deficient but somehow allowed to be in the seat, but what of the previous crew that figured it out and hand flew the plane safely to the destination?

The resident experts have discounted this flight because there was an extra pilot in the cockpit who was not startled by all the warning lights going off, so while the crew dealt with those he had the freedom to think, recognize the issue incorrectly as run away trim and recommend using the cut-off switches. The more important question is did he really recognize run away or he actually knew about MCAS...there is still a lot of dispute as to where, how and who were advised of the existence of MCAS.

morrisond · Fri Nov 01, 2019 2:32 am

dtw2hyd wrote:
morrisond wrote:

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

Have you read the report? FO used ANU trim six times.

23:30:48 - Captain asked FO to take control (Pitch Trim 4.8)
23:30:49 - FO ANU trim for 3 seconds
23:30:52 - FO - I have control
23:31:00 - Automatic trim for 8 seconds (Pitch Trim from 5.4 to 3.4)
23:31:08 - FO - ANU trim for 1 second (Pitch 3.5)
23:31:15 - MCAS for 3 seconds
23:31:17 - FO - ANU trim for 1 second (Pitch 2.9, back pressure 65 lbs)
23:31:19 - FO - ANU trim for 4 seconds (Pitch 3.4)
23:31:27 - MCAS for 8 seconds (Pitch 1.8, back pressure 82 lbs)
23:31:37 - FO - ANU trim for 2 seconds (Pitch 1.3)
23:31:43 - MCAS for 4 seconds (Pitch 0.3, back pressure 93 lbs)
23:31:46 - FO - ANU trim for 2 seconds (Captain PFD 3200ft, FO PFD 3600ft, rate of descent 10,000 ft/sec)
23:31:51 - TERRAIN and SINK RATE warnings
23:31:53 - MCAS activated until recording stopped. This must be a proud moment for the software team.

Yes I did and he never did it for long enough - what is your point?

djm18 · Fri Nov 01, 2019 4:47 am

dtw2hyd wrote:
morrisond wrote:

23:31:19 - FO - ANU trim for 4 seconds (Pitch 3.4)
23:31:27 - MCAS for 8 seconds (Pitch 1.8, back pressure 82 lbs)
23:31:37 - FO - ANU trim for 2 seconds (Pitch 1.3)
23:31:43 - MCAS for 4 seconds (Pitch 0.3, back pressure 93 lbs).

Is it possible that the FO became frustrated with the increasing yoke pressure, and that in 23:31:37 he pitched in the opposite direction to see if that would perhaps make things better? he may have done this not knowing that mcas was at work and thinking that he was previously trimming in the wrong direction given the ever increasing pressure despite his trim inputs.

just a thought, was struck to see the pitch go from 1.8 to 1.3 in that specific instance.

Chemist · Fri Nov 01, 2019 5:10 am

StTim wrote:
Chemist wrote:
StTim wrote:
Do you know what - I actually don't care if the crew could have saved the plane. They should never have been put in that position. End of - period.

This saga started with terrible design and ended with pilots fighting for their - and their passengers lives.

I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

I agree with your statements. But do you really think an FO that doesn't use trim and can't find checklists they are supposed to have memorized is reasonably well trained?

But remember there was only a but of differences training for the crews who flew the MAX over the NG and in the AoA setting off the MCAS they were in uncharted territory that they had not been trained for.

Not knowing how to use trim or find checklists is independent of any MAX vs NG training.

oschkosch · Fri Nov 01, 2019 5:41 am

AA news! Sounds like it is getting more difficult!

https://www.reuters.com/article/us-boei ... SKBN1XA2JO

American Airlines’ flight attendants union still has safety concerns about the Boeing 737 MAX and is demanding an active role in the relaunch of the grounded aircraft, its president told Boeing Co’s (BA.N) chief executive in a letter seen by Reuters.

“The 28,000 flight attendants working for American Airlines refuse to walk onto a plane that may not be safe and are calling for the highest possible safety standards to avoid another tragedy,” Association of Professional Flight Attendants President Lori Bassani said in the letter.

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rheinwaldner · Fri Nov 01, 2019 6:34 am

dtw2hyd wrote:
What good was Airspeed Unreliable checklist? Was it even the correct checklist for the problem as manifested?

No, it was the wrong one because the alarm was wrong. And the other two alarms they got were also wrong. 3 false alarms and no alarm of the system that was really deadly.

Because of that, the report lists 25 findings, that take away blame from the explicitely (statements like: this would lead to the inability of the crew to react correctly). Only 7 findings do blame the crew. The report does absolve the crew to a large degree.

seahawk wrote:
And if you have to trim up 22 times, one can expect a reasonably skilled crew to come up with the runaway trim checklist and disable the system. The crews showed unacceptable bad crew resource management and lacked basic flying skills, which must be seen as the final factors for the crash.

Trimming happens as you steer your car. You are not really aware of the corrections and dont notice the directions and dont count the inputs. And as small stick forces were continuously canceled out, the corrections were small and it felt naturally. There was no clue from the system, that the small mistrims that occured 26 times were coming froming a hidden trim system itself. And the frequent small corrections masked the brutally long cycle, MCAS would have ran otherwise.

Please also consider, that the accident report does not nearly put weight on the crew errors that you do. In other words, you are making stuff up.

morrisond wrote:
The accident rates being lower doesn't necessarily mean the crews are getting better

This statement damages your credibility strongly. Crew error was always the dominant reason for crashes, so how could overall safety improve without the crews making less errors?

2nd remark:
If aviation safety demonstrably improved by a mangnitude of orders in the last decades, why do you want to go further? Aviation safety is the goal. If aviation safety is acceptable, the goal is reached.
[img] Aviation safety is the goal.

Chemist wrote:
But do you really think an FO that doesn't use trim and can't find checklists they are supposed to have memorized is reasonably well trained?

You forget, that the MAX created an extremely hostile einviroment for this crew. They got three false alarms which indicated non existing threats, but these covered the real threat, designed to kill them. This situation was fault provoking and caused tunnel vision. You are intelectually dishonest, if you try to draw conclusions about the normal performance of this crew from how the crew handled thsi situation.

morrisond wrote:
StTim wrote:
I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

You need to read the JT crash final report - they were not even close to average in terms of ability.

Yes, read it! And stick with the findings of it rather than spinning your own version of it. Try to read the rest of the report instead of the few pages, that you quoted so far. Then you see, that StTim was right.

morrisond wrote:
dtw2hyd wrote:
morrisond wrote:

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

Have you read the report? FO used ANU trim six times.

23:30:48 - Captain asked FO to take control (Pitch Trim 4.8)
23:30:49 - FO ANU trim for 3 seconds
23:30:52 - FO - I have control
23:31:00 - Automatic trim for 8 seconds (Pitch Trim from 5.4 to 3.4)
23:31:08 - FO - ANU trim for 1 second (Pitch 3.5)
23:31:15 - MCAS for 3 seconds
23:31:17 - FO - ANU trim for 1 second (Pitch 2.9, back pressure 65 lbs)
23:31:19 - FO - ANU trim for 4 seconds (Pitch 3.4)
23:31:27 - MCAS for 8 seconds (Pitch 1.8, back pressure 82 lbs)
23:31:37 - FO - ANU trim for 2 seconds (Pitch 1.3)
23:31:43 - MCAS for 4 seconds (Pitch 0.3, back pressure 93 lbs)
23:31:46 - FO - ANU trim for 2 seconds (Captain PFD 3200ft, FO PFD 3600ft, rate of descent 10,000 ft/sec)
23:31:51 - TERRAIN and SINK RATE warnings
23:31:53 - MCAS activated until recording stopped. This must be a proud moment for the software team.

Yes I did and he never did it for long enough - what is your point?

That you were wrong, saying the FO did not trim at all.

AirBoat · Fri Nov 01, 2019 7:27 am

For the Lion air case: the question is why did they stop trimming nose up?
there are 2 possibilities:
1. they did not know how.
2. the electric trim drive motor failed. There are signs of intermittent trim action just before the final moments.
This could open up another can of worms. What was the duty cycle of the trim motor. If is was designed for 100% duty continuously then there is no problem.
And by the way, both pilots were pulling with all their strength on the yoke at the end, the pilot 100lbs and co-pilot 40lbs.

dtw2hyd · Fri Nov 01, 2019 10:59 am

morrisond wrote:
Yes I did and he never did it for long enough - what is your point?

Point is FO knew how to use the trim switch, contrary to the repeated spin here. In fact, it was his first act even before he said: "I have control".

How long, when there is a stall warning, do you expect indiscriminate nose-up trim. Then the news would be "Inexperienced third world FO unknowingly stalled the plane"

On the other hand, no software developer who is helping the pilot should nose down, when there are TERRAIN and SINK RATE warnings. Even a simple tracking of pitch trim or having any one of the obvious interrupts would have saved the day.

Why do you think autopilot disengages, it is not because those who developed are less smarter than MCAS team.

seahawk · Fri Nov 01, 2019 11:09 am

Any decent pilot should be able to notice when the plane is trimmed neutral and should trim accordingly.

morrisond · Fri Nov 01, 2019 11:16 am

rheinwaldner wrote:
seahawk wrote:
And if you have to trim up 22 times, one can expect a reasonably skilled crew to come up with the runaway trim checklist and disable the system. The crews showed unacceptable bad crew resource management and lacked basic flying skills, which must be seen as the final factors for the crash.

Trimming happens as you steer your car. You are not really aware of the corrections and dont notice the directions and dont count the inputs. And as small stick forces were continuously canceled out, the corrections were small and it felt naturally. There was no clue from the system, that the small mistrims that occured 26 times were coming froming a hidden trim system itself. And the frequent small corrections masked the brutally long cycle, MCAS would have ran otherwise.

Please also consider, that the accident report does not nearly put weight on the crew errors that you do. In other words, you are making stuff up.

Are you a pilot? Have you ever flown a plane? Then you would realize how ridiculous the above statement is as it is entirely wrong. The FO noticed that the controls were getting heavier and remarked on it. You can see it below in another quote where you attacked me. He just didn't understand that he had to trim longer ANU to offset the forces. He must not have noticed the trim wheel spinning away.

Seahawk wasn't making anything up - He just didn't put the disclaimer on his post that "Boeing is the root cause" which seems to be what we have to do around here on every post or someone will go off the deep end.

Even after the JT final report has been released showing multiple significant factors to the crashes and it pointed out things that have to change (Maintenance, training) - you are still trying to Pin the accident 100% on Boeing and ignoring everything else.

Isn't about time that the Boeing is evil crowd (and BTW I do believe what happened inside Boeing was beyond bad) and nothing else matters need to put some sort of disclaimer on there statements as well? "Granted there were serious mistakes that were made in Maintenance and Training that need to be fixed" or something like that before ranting on?

rheinwaldner wrote:
morrisond wrote:
StTim wrote:
I don't planes that need the creme de la creme to fly them. I want planes that the average pilot, reasonably well trained can fly safely. That seems to be about every other plane bar the MAX!

You need to read the JT crash final report - they were not even close to average in terms of ability.

Yes, read it! And stick with the findings of it rather than spinning your own version of it. Try to read the rest of the report instead of the few pages, that you quoted so far. Then you see, that StTim was right.

I read the whole report - the KNKT investigators called out the Pilots for Bad airmanship multiple times - maybe you need to read it.

rheinwaldner wrote:
morrisond wrote:
dtw2hyd wrote:

Have you read the report? FO used ANU trim six times.

23:30:48 - Captain asked FO to take control (Pitch Trim 4.8)
23:30:49 - FO ANU trim for 3 seconds
23:30:52 - FO - I have control
23:31:00 - Automatic trim for 8 seconds (Pitch Trim from 5.4 to 3.4)
23:31:08 - FO - ANU trim for 1 second (Pitch 3.5)
23:31:15 - MCAS for 3 seconds
23:31:17 - FO - ANU trim for 1 second (Pitch 2.9, back pressure 65 lbs)
23:31:19 - FO - ANU trim for 4 seconds (Pitch 3.4)
23:31:27 - MCAS for 8 seconds (Pitch 1.8, back pressure 82 lbs)
23:31:37 - FO - ANU trim for 2 seconds (Pitch 1.3)
23:31:43 - MCAS for 4 seconds (Pitch 0.3, back pressure 93 lbs)
23:31:46 - FO - ANU trim for 2 seconds (Captain PFD 3200ft, FO PFD 3600ft, rate of descent 10,000 ft/sec)
23:31:51 - TERRAIN and SINK RATE warnings
23:31:53 - MCAS activated until recording stopped. This must be a proud moment for the software team.

Yes I did and he never did it for long enough - what is your point?

That you were wrong, saying the FO did not trim at all.

No - I did not say he never used it I said he never used it properly. There is a big difference between the two.

Is English not your first language? I'm not asking that to be an ass - it just seems that sometimes you are taking things way too literally and that is where a lot of conflict is coming from.

Your written english is great - and probably a lot better than mine.

morrisond · Fri Nov 01, 2019 11:18 am

seahawk wrote:
Any decent pilot should be able to notice when the plane is trimmed neutral and should trim accordingly.

Any pilot who successfully completes the first few hours of basic training should be able to do that - it should be a reflex reaction within the the first 20-30 hours.

It's incomprehensible how someone with that much experience didn't know how to trim correctly.

planecane · Fri Nov 01, 2019 11:32 am

oschkosch wrote:
AA news! Sounds like it is getting more difficult!

https://www.reuters.com/article/us-boei ... SKBN1XA2JO

American Airlines’ flight attendants union still has safety concerns about the Boeing 737 MAX and is demanding an active role in the relaunch of the grounded aircraft, its president told Boeing Co’s (BA.N) chief executive in a letter seen by Reuters.

“The 28,000 flight attendants working for American Airlines refuse to walk onto a plane that may not be safe and are calling for the highest possible safety standards to avoid another tragedy,” Association of Professional Flight Attendants President Lori Bassani said in the letter.

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What expertise do FAs have here? If the PILOTS agree that it is safe to fly then the FAs shouldn't have an issue. The pilots make that call on every flight every day. Should the FAs have a say every flight? I don't think so.

seahawk · Fri Nov 01, 2019 11:48 am

As I previously said the crew performance and the design error are not directly connected.

Just if you look at the trim inputs, it becomes obvious that without coming to the conclusion that it is a runaway trim, they could not win the struggle. In 10 seconds MCAS trimmed from 6,1 units to 3,8 units, while 5 seconds of manual trim only set the trim back to 4,7 units. So MCAS did trim for 0,23 units per second, while manual electric trim only trims for 0,18 units per second.

But we also see the the pilot used manul inputs to stop the MCAS quickly and was able to control the trim quite well. The FO re-acted slower and counter trimmed less. When handing over control the pilot failed to inform the FO of the constant need to counter a trim movement manually. That is bad crew management.

It does not make the mistakes by Boeing any better.

mjoelnir · Fri Nov 01, 2019 11:52 am

planecane wrote:
oschkosch wrote:
AA news! Sounds like it is getting more difficult!

https://www.reuters.com/article/us-boei ... SKBN1XA2JO

American Airlines’ flight attendants union still has safety concerns about the Boeing 737 MAX and is demanding an active role in the relaunch of the grounded aircraft, its president told Boeing Co’s (BA.N) chief executive in a letter seen by Reuters.

“The 28,000 flight attendants working for American Airlines refuse to walk onto a plane that may not be safe and are calling for the highest possible safety standards to avoid another tragedy,” Association of Professional Flight Attendants President Lori Bassani said in the letter.

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What expertise do FAs have here? If the PILOTS agree that it is safe to fly then the FAs shouldn't have an issue. The pilots make that call on every flight every day. Should the FAs have a say every flight? I don't think so.

We have seen the expertise of the test pilots at Boeing when judging the safety of the 737MAX. Dismal results.

planecane · Fri Nov 01, 2019 12:32 pm

mjoelnir wrote:
planecane wrote:
oschkosch wrote:
AA news! Sounds like it is getting more difficult!

https://www.reuters.com/article/us-boei ... SKBN1XA2JO

American Airlines’ flight attendants union still has safety concerns about the Boeing 737 MAX and is demanding an active role in the relaunch of the grounded aircraft, its president told Boeing Co’s (BA.N) chief executive in a letter seen by Reuters.

“The 28,000 flight attendants working for American Airlines refuse to walk onto a plane that may not be safe and are calling for the highest possible safety standards to avoid another tragedy,” Association of Professional Flight Attendants President Lori Bassani said in the letter.

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What expertise do FAs have here? If the PILOTS agree that it is safe to fly then the FAs shouldn't have an issue. The pilots make that call on every flight every day. Should the FAs have a say every flight? I don't think so.

We have seen the expertise of the test pilots at Boeing when judging the safety of the 737MAX. Dismal results.

I'm talking about the AA pilots who put their lives on the aircraft and who now have all information about the MAX and MCAS. They have the expertise to understand the aircraft and the changes made. FAs do not have the education and expertise to determine the safety of the MAX.

planecane · Fri Nov 01, 2019 12:35 pm

seahawk wrote:
As I previously said the crew performance and the design error are not directly connected.

Just if you look at the trim inputs, it becomes obvious that without coming to the conclusion that it is a runaway trim, they could not win the struggle. In 10 seconds MCAS trimmed from 6,1 units to 3,8 units, while 5 seconds of manual trim only set the trim back to 4,7 units. So MCAS did trim for 0,23 units per second, while manual electric trim only trims for 0,18 units per second.

But we also see the the pilot used manul inputs to stop the MCAS quickly and was able to control the trim quite well. The FO re-acted slower and counter trimmed less. When handing over control the pilot failed to inform the FO of the constant need to counter a trim movement manually. That is bad crew management.

It does not make the mistakes by Boeing any better.

They could have won the struggle. If, each time, they trimmed back to neutral column force (like is supposed to be done as part of normal manual flight) then they would have just kept oscillating back and forth between neutral and 2.5 units out of trim nose down until they set flaps 1 in preparation for landing. It doesn't matter if it took them longer to offset MCAS than it took MCAS to reach a particular point. Trim is not done by time, it is done by feel.

dtw2hyd · Fri Nov 01, 2019 12:43 pm

morrisond wrote:
seahawk wrote:
Any decent pilot should be able to notice when the plane is trimmed neutral and should trim accordingly.

Any pilot who successfully completes the first few hours of basic training should be able to do that - it should be a reflex reaction within the the first 20-30 hours.

It's incomprehensible how someone with that much experience didn't know how to trim correctly.

Any student of Fortran Programming 101 since mid-60s in their first lab would know what happens to an infinite loop without exit condition.

XRAYretired · Fri Nov 01, 2019 1:02 pm

planecane wrote:
mjoelnir wrote:
planecane wrote:
What expertise do FAs have here? If the PILOTS agree that it is safe to fly then the FAs shouldn't have an issue. The pilots make that call on every flight every day. Should the FAs have a say every flight? I don't think so.

We have seen the expertise of the test pilots at Boeing when judging the safety of the 737MAX. Dismal results.

I'm talking about the AA pilots who put their lives on the aircraft and who now have all information about the MAX and MCAS. They have the expertise to understand the aircraft and the changes made. FAs do not have the education and expertise to determine the safety of the MAX.

I wouldn't make yourself known to any FAs in the near future.

It is only recently that Boeing did not trust AA pilots with any technical detail or complexity so as not to overburden them and were short changed on AFM, FCOM and training and potentially even lied to, so would not be sure your precept is true. Given the current loss of credibility in Boeing and FAA as well, I wonder who can be turned to, who can provide some confidence? One thing for sure, you are going to ask the question if you are a FA who rides the beast every day and life and livelihood depends on the safety of flight.

Ray

seahawk · Fri Nov 01, 2019 1:16 pm

planecane wrote:
seahawk wrote:
As I previously said the crew performance and the design error are not directly connected.

Just if you look at the trim inputs, it becomes obvious that without coming to the conclusion that it is a runaway trim, they could not win the struggle. In 10 seconds MCAS trimmed from 6,1 units to 3,8 units, while 5 seconds of manual trim only set the trim back to 4,7 units. So MCAS did trim for 0,23 units per second, while manual electric trim only trims for 0,18 units per second.

But we also see the the pilot used manul inputs to stop the MCAS quickly and was able to control the trim quite well. The FO re-acted slower and counter trimmed less. When handing over control the pilot failed to inform the FO of the constant need to counter a trim movement manually. That is bad crew management.

It does not make the mistakes by Boeing any better.

They could have won the struggle. If, each time, they trimmed back to neutral column force (like is supposed to be done as part of normal manual flight) then they would have just kept oscillating back and forth between neutral and 2.5 units out of trim nose down until they set flaps 1 in preparation for landing. It doesn't matter if it took them longer to offset MCAS than it took MCAS to reach a particular point. Trim is not done by time, it is done by feel.

That is being lucky. The only way to actually win is recognize the MCAS activations as a runaway trim, and trim neutral before hitting the switches.

glideslope · Fri Nov 01, 2019 1:25 pm

morrisond wrote:
PW100 wrote:
sgrow787 wrote:

"Observation O6.9-H: Boeing concluded that multiple erroneous MCAS activations were not worse than a single erroneous activation, based on the assumption that the crew would return the aircraft to a trimmed state (consistent with AC 25-7C guidance) following each activation."

It would seem to me, a non-pilot, that the increase in airspeed that comes with MCAS AND action, would result in the pilot needing less pitch correction to return to stable flight. Would this explain the lack of return of the stab trim all the way to what it was pre-AND?

BTW, from what I can tell from the DFDR plots, the authority from the eTrim is only 0.15 deg/sec, which is about 40% less than the 0.27 deg/sec (2.5 [deg/cyc] / 9 [sec/cyc]) from MCAS, which is significant.

Also, in one of the earlier threads, we were told that any decently trained pilot would not put in electric trimming in one loooong go, especially at higher speeds, but in short blips. Then evaluating the effect, and if needed, put in another short burst. But during the evaluation, MCAS run-away becomes alive again, and aggressively trims the nose down, at much higher rate than electric up-trimming could do at that point.

A decently trained pilot would have realized they were way out of trim and held that switch down until the forces were neutralized - just like the JT Captain did - he actually didn't do too bad - just never made the intuitive leap to turn off the system after 22 times - maybe 23 times would have done it - before turning it over to this FO and forgetting to tell him what he had to do to offset what MCAS was doing to the plane.

Maybe it was so obvious that he assumed he didn't have to tell him but that was really CRM.

Agree completely. While I'm hesitant to engage in this explosive thread JT was really all about CRM. They both were flying instead of one flying and one running the lists. An earlier post referred to Boeing's bad design on the Max as being an IQ Test for pilots. Unfortunately this is a very accurate analogy IMO. While I am still under the opinion that ET was more recoverable than JT (I don't believe JT should have been signed off as flight ready) in both cases there were large CRM issues created by a lack of training from the withholding of information from Boeing. I just hope Boeing can recover from this. Aviation needs competition. I'm no more enthusiastic over flying in a C919 than a Max.

mrbots · Fri Nov 01, 2019 1:29 pm

Haven't seen this posted (but who can keep up with every post and page here...) in the discussion on what MCAS is for, from Boeing's 737 MAX update website:

"Maneuvering Characteristics Augmentation System (MCAS) - flight control law implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack"

"The Maneuvering Characteristics Augmentation System (MCAS) flight control law was designed and certified for the 737 MAX to enhance the pitch stability of the airplane - so that it feels and flies like other 737s."

Lots of other information there as well. https://www.boeing.com/737-max-updates/

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