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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 11:20 am

Interested wrote:
According to the lawsuit reported in this article - the same tactics to hide design flaws and deflect blame onto the pilots have been used on previous Boeing crashes

https://www.cnn.com/2019/05/21/politics ... index.html

From the document:
109. BOEING intentionally designed the MCAS to take data from one of the 737 MAX 8's two angle of attack (AOA) sensors and to alternate the sensor from which it accepts data each flight.
110. BOEING hos not publicly disclosed why it decided to have the MCAS take data from only one indicator,
[...]
113. Even though Rockwell Collins (Collins Aerospace) build the 737 MAX 8 flight control computer and the software and coding that run the MCAS, and Rosemount manufactured and supplied the Angle of Attack indicator, BOEING remains responsible for its suppliers and contractors, and for the design, production, manufacture, certification and airworthiness of its BOEING aircraft,
114. Rockwell Collins witch produced the flight controls computers and software on the 737 MAX 8 also provided software update to BOEING after the crash of Lion Air in 2018, but BOEING has not taken the necessary action to make all changes needed on 737 MAX 8 and the subject aircraft before the crash of Ethiopian Airlines Flight 302.
[... lot of blames on BOEING ...]
134. As a result of BOEING's intentional and knowing decisions, the pilots of the subject aircraft had not received any simulator training or testing on how to handle emergencies caused by the BOEING 737 MAX 8 airplane's MCAS.
135. BOEING knowingly failed to conduct a proper failure mode and effect analysis during development of the BOEING 737-8 MAX to ensure that the airplane's MCAS was safe.
[...]
139, In BOEING's rush to get the 737 MAX 8 to market, BOEING knowingly, intentionally, wantonly, callously, egregiously, negligently, and possibly criminally, compromised and endangered the safety of BOEING 737 MAX 8 crews and passengers, and killed two plane loads of people.

BOEING DECEIVED THE FAA AND PURCHASERS OF THE BOEING 737-8 MAX BY
ASSERTING THAT CRITICAL SAFETY FEATURES NEED NOT BE STANDARD,
OFFERING THEN ONLY AS OPTIONAL EQUIPMENT AT EXTRA COST

140. Evidence that BOEING put its profits ahead of safety in its design, production, assembly, manufacture, and marketing of the BOEING 737 MAX 8 airplane includes that BOEING charged it customers extra for the installation of important safety features.
[...]
155. BOEING has so completely assumed the FAA certification process that the FAA airworthiness certification of an airplane or airplane system no longer means that the FAA independently considered and determined whether that airplane or airplane system was safe, but rather that BOEING has largely supplemented the role of the FAA. For example: [...]
[... lot of blames about the BOEING lobbying the U.S federal government ...]
BOEING "FIX" AFTER TEH LION AIT CRASH DID NOT WORK
210. Rather than grounding the Boeing 737 MAX 8 until it was fixed and made safe, BOEING chose to prioritize profits over passenger safety, keeping its Boeing 737 MAX 8 airplane in service first after Lion Air and again after subject crash, intentionally misleading its customers, the FAA, passengers and the public that the airplane was safe to fly. Such acts and omissions demonstrate intentional reckless indifference and conscious disregard for the safety of the flying public and Decedent.
[...]
THE PILOTS DID NOT CAUSE THE PLANE TO MALFUNCTION
250. The pilots had completed all the training which BOEING claimed was necessary to operate the aircraft.
251. The pilot(s) on the subject aircraft followed the protocol that had been make known to them as best they could under emergent circumstances, with little altitude and thus little time to troubleshoot and overcome the MCAS system.
[...]
254. The investigations by the air accident investigators to date has not found other cause that interfered with normal operation or caused the crash.
[... no less than 11 counts ...]
 
Mike931
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 11:41 am

manual trim wheel training is a must and I hope they will take care of it.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 11:45 am

aerolimani wrote:
It's verging on off-topic, but let's not bring the A320 trim wheels into this discussion. There is no situation where the A320 trim wheels are actually mechanically controlling the trim system. The A320's stabilizer trim screwjack is operated only by two hydraulic motors. The A320's trims wheels are not connected by a cable to the screwjack, like the 737. So, there will never be a situation where the A320's wheels experience direct mechanical feedback from the stab. It is impossible. The wheels are basically a just fancy switches, and a visual reference for the pilots.

A320 horizontal stabilizer trim is operated by 3 electrical motors from the ELAC1 or ELAC2 or SEC1 or SEC2. Mechanical control of the THS is available from the pitch trim wheel at any time if either the green or the yellow hydraulic system is functioning. Mechanical control from the pitch trim wheel has priority over electrical control.
https://www.airliners.net/forum/viewtopic.php?f=3&t=1421471&start=1950#p21395469

To control the trim horizontal stabilizer (THS) on a A320 the redundancy includes:
* 3 sensors, 4 computers (each with a control CPU and a monitoring CPU), and 3 electrical motors for the electric control.
* 2 hydraulic motors for the mechanical control.
Compared to the B737, the A320 THS is build like for war operation. So much that the new A350 is actually not so paranoid with only 2 electrical motors and a double trim switch, but a lot of computers spread over an AFDX redundant network.
Last edited by PixelFlight on Fri May 31, 2019 12:06 pm, edited 1 time in total.
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:00 pm

planecane wrote:
kalvado wrote:
One can envision a few possible failures creating artificial stop.
Pure speculation below:
- at high force point, backup nut separated from the mount and prevented main nut going up the jackscrew acting as a lock nut.
- At high force, one of the nuts damaged jackscrew preventing other nut moving over that spot.

I can come up with a few more scenarios


Those scenarios are definitely possible. Hopefully they have been able to analyze the jackscrew to determine if a physical failure did happen. I just think it would be a heck of a coincidence that they stopped pressing the switch or moved the cutout switches at the exact moment that the stabilizer was physically prevented from moving. It's not like there is force feedback on the thumb switch.


Do we know where the DFDR picks up the trim command signal?

I think it was previously suggested (in this thread, or another one) that it may be embedded in the thump switch circuit, but has that been confirmed somehow? Could it be that the DFDR picks ups that command signal somewhere else, further away, possibly at the trim motor itself?

It should be noted that the DFDR trim parameter also contains automatic trim info, so it definitely cannot be just the trim switch circuit alone sending trim command signal to DFDR.
So it is possible then, that the info in the DFDR is not just raw thump switch position info, there is probably more to it. Then we should observe some carefulness in drawing conclusions on switch position and DFDR trace.
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:13 pm

planecane wrote:
Interested wrote:
Would be really interesting to know how many times manual trim has had to be used on NG 737s. Not only that - how aggressive was the situation they were trying to rectify?
I guess in the past whenever it's had to be used its not been a time when the plane keeps trying to crash itself?
Anyone know?

I would also investigate any future flights that have to use manual trim but don't crash with the same attention to detail they give to planes that do crash. There must be so much tgat can be learnt from those flights.
I will add that there is probably as much to learn if not more to learn from what the pilots on the lion air plane that had issues but didn't crash and what they faced when things started going wrong for them.


It would be interesting to have that information. My guess is that any time the manual trim wheel has been used on the NG, it's been because the trim stopped functioning but they were starting pretty close to being in trim. I would assume that the wheel is not difficult to use when the aircraft is close to being in trim.

I'd also be curious when the last time was that there was a 737 runaway stabilizer pre-MCAS and how many times it has happened per million flights since the introduction of the classic series in 1984. My suspicion is that it is an incredibly rare event.


I agree with all your remarks.
I'd add that if Boeing can demonstrate that such event is so rare (i.e < 10E-9), that it would be considered an acceptable risk, needing no further action. The hundreds of millions of flight hours accumulated by NG series would go a long way proving such.

Of course MCAS 1.0 introduced an new failure mode, basically replicating the failure rate of the AoA sensor. And that is not good enough, by several orders of magnitude. The MAX does not have the long history to demonstrate such reliability. Au contraire!

But if Boeing can demonstrate failure rate of MCAS 2.0 (leading to said sever-out-of-trim condition) is similar to traditional failure rate of trim run-away/severely mis-trim on NG, then that may be acceptable as well.
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Interested
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:16 pm

smartplane wrote:
xmp125a wrote:
ArgentoSystems wrote:


In grandfatheringspeak, it is a light :)

(if pre-NG aircraft had that functionality it could only be a light, right?)

Thank you xmp. A symbol illuminates / icon is displayed / lights up.

Why didn't Boeing disclose the inoperative icon display if known since 2017?


We don't know why - but we do know that yesterday the CEO admitted this was a mistake on Boeing's part
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:22 pm

Interested wrote:
smartplane wrote:
xmp125a wrote:

In grandfatheringspeak, it is a light :)

(if pre-NG aircraft had that functionality it could only be a light, right?)

Thank you xmp. A symbol illuminates / icon is displayed / lights up.

Why didn't Boeing disclose the inoperative icon display if known since 2017?


We don't know why - but we do know that yesterday the CEO admitted this was a mistake on Boeing's part

Wait a few days. It will evolve into "this was a contributing factor, but..."
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:33 pm

PW100 wrote:
Do we know where the DFDR picks up the trim command signal?

I think it was previously suggested (in this thread, or another one) that it may be embedded in the thump switch circuit, but has that been confirmed somehow? Could it be that the DFDR picks ups that command signal somewhere else, further away, possibly at the trim motor itself?

It should be noted that the DFDR trim parameter also contains automatic trim info, so it definitely cannot be just the trim switch circuit alone sending trim command signal to DFDR.
So it is possible then, that the info in the DFDR is not just raw thump switch position info, there is probably more to it. Then we should observe some carefulness in drawing conclusions on switch position and DFDR trace.

It's more than suggestion. The Aviation Herald publish a pertinent schematic for that part: http://avherald.com/img/ethiopian_b38m_et-avj_190310_10.jpg

The manual electric trim command signals are directly pick up by the DFDAU (M675 box between the two trim switches boxes) before the column switches modules and all the other relay and switches down to the trim motor actuator. The automatic trim signals use a completely different circuit. In fact there are two input interfaces to the trim motor controller, one from the main trim and a other for the autopilot. So the DFDAU pick up the automatic trim independently from the manual trim, consistently with all the FDR traces published so far. All those signals could be interrupted (either by switches/relay or electrical fault) so at the end only the stab trim position stand up. The signals only help to correlate the probable source of the stab trim change.
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:40 pm

xmp125a wrote:
planecane wrote:
Another video I found from 2015 of a runaway trim in a 737 classic simulator. They cutout the electric trim quickly without really going through the checklist and then trimmed with the wheel. The interesting thing is that disengaging autothrottle and reducing thrust was done by instinct. I can't really tell how out of trim they got but they didn't do a rollercoaster procedure but they did point out the force the copilot was using to hold the column before they got back in trim.

https://www.youtube.com/watch?v=3pPRuFHR1co


1) Classic has larger trim wheels than either NG or max.
2) The MAX simulators (curiously, what about NG ones??) did not realistically simulate forces needed to stabilize out of trim plane using the wheels. MAX simulators did not include MCAS simulation, and did not include proper resistance on trim wheel, I have difficulties believing that they somehow botched this in transition from NG to MAX, so the issue must be older than MAX.

Therefore, it is plausible that the FO on ET flight would be surprised about the resistance he encountered, even if he trained that exact situation in the simulator - his experience would be different in flight than in simulator what is probably the thing you do not want in 1000/hr simulator training!

Again, damning for Boeing.


And again you ignore the fact that thrust was left at TOGA and they were above Vmo. It's like faulting Boeing for the plane falling out of the sky at 40knots below stall speed.
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:49 pm

xmp125a wrote:
morrisond wrote:
Nice - taking partial quotes again and ignoring my comments about training. I have always said it's a training issue.


If discussing training, let's be clear on one thing.

1) NG procedures training - responsibility of the airline.
2) MAX specific training - 100% responsibility of Boeing.
3) Any divergence between the real airplanes and the simulator - 100% responsibility of Boeing.

Pilots all over the world were calling for better disclosures by Boeing and/or additional training after Lion Air crash (meeting in USA, pressure of senior pilot on ET), but "all they got was a poorly written EAD" (which still relies on the fact that pilots distinguish between real trim runaway and MCAS-induced one).


MAX Specific training design was the responsibility of Boeing - it was up to the Airlines to ensure it was taught and understood. After Lionair the Boeing new procedures should have been enough - it's pretty clear - but it was up to the Airlines to distribute them and make sure it's Pilots understood them - especially if they had questions.

What part of the FCOM that ET supposedly gave it's pilots - or if the ET Captain is right - gave them but with no discussion or training on it - fails to fully describe the problem - the symptoms you might see and how to handle it?

It's on Page 32-33 og the Pre-Lim https://leehamnews.com/wp-content/uploa ... ET-AVJ.pdf

From that ET Captain - it sounds like ET never taught the new procedure in the SIM anyways so why would it matter if the simulator fidelity wasn't perfect?
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 12:49 pm

morrisond wrote:
Interested wrote:
So if you agree with the above isn't that substantial enough to stop worrying about the pilots actions and to focus on what Boeing need to do to stop pilots anywhere in the world facing a similar situation in the future.
. . . .
For sure Morrison if you want these guys trained to use the trim etc let's do it as well. But that's not the real issue here. The Max flawed design has led us to spend weeks analysing and dissecting the ins and outs of something we should never even need to be discussing.


Nice - taking partial quotes again and ignoring my comments about training. I have always said it's a training issue.

You better never fly on an A320 then either as it has a backup trim wheel.

The technical writer said - it might have been saved - there was a lot of hedging in his response. If they had trimmed out the out of trim with Electric before switching it off or never put up the flaps or disengaged TOGA thrust they might have been saved as well.


There is NO evidence that the pilots did not properly use electric trimming. Au contraire, the FDR charts clearly show the use of electric up-trimming being applied many times. So they did understand how that works . . .

The FDR traces show a total of four electric up-trims after MCAS became alive. And ALL FOUR of them stopped at exactly the same pitch trim: 2.3 degrees. Coincidence? Can any crew do such a thing on purpose? I'm having a hard time accepting that.
It must be noted that after take-off, electric trimming was applied several times (both up and down) resulting in a balanced control column. So again, they clearly knew how that works . . .

The cut out switches were flipped before the control column was balanced in pitch. You (again) ASSUME that was by pilot action. We have no evidence of that.

So the question is, a) did up-trimming stop because the cut-out switches were flipped, or b) did they flip the switches because electric up-trimming stopped (uncommandedly) and was not working for them (beyond 2.3 deg Pitch Trim)?
I can’t find that answer in the report nor the FDR traces. You though, seem to have made your mind up already . . .

With respect to the flaps, the pilots could not have known the interaction between flaps up and MCAS waking up. What checklist should they have followed, preventing them from putting up the flaps?
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:01 pm

smartplane wrote:
Interested wrote:
XRAYretired wrote:
Ethiopian have one. Southwest could sub-contract pilot training to them! :duck:


If only the one they had could replicate MCAS

And trim wheel loads, and.................


I don't think any simulator would be able to simulate trim wheel loads at above Vmo and TOGA thrust - nor should it. That would be an immediate fail in any simulator check session.

If you couldn't control your airspeed they would never let you out of the sim and into a cockpit.
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:06 pm

morrisond wrote:
mjoelnir wrote:
Boeing did practical nothing. They did not explain how MCAS functioned. They did not give out how you recognize and train for MCAS failure mode. They did not fix the simulators so they would show how MCAS works and how it behaves with an AoA failure.
Boeing just pointed to the runaway trim procedure.
Boeing even kept quite over the non existence of the light declaring AoA disagree, pointing exactly at the situation that could produce a MCAS going amok situation. Even if this light should have been a standard feature and being described in the manual.

It is astonishing how you want to leave Boeing of the hook and accuse everybody else.


Please read Page 32-33 of the preliminary crash report - how does that not make the condition clear and show a way to deal with it. This is a different procedure than runaway trim.


We have no evidence they did not carry out the Page 32-33 procedure. Au contraire. They did use the cut-off switches.

I assume you blame the ET crew for two things with respect to this procedure:
A) not using electric trimming to neutralize control column forces;
B) Turning electric trimming back-on, as opposed to the procedure.

A) As I have debated earlier, we have no evidence that electric trimming was stopped by crew action. Further, the text suggesting to neutralize control column before using the cut-out switches, is not an instruction. It is a note. And is says that “electric stabilizer trim CAN be used to . . .” How is that an instruction? IT'S A NOTE, SUGGESTION. And somehow, apparently may have not worked for them.

B) We do have (several) indications that the above was not working out for them, and probably in desperation may have decided to turn electric trimming back on again. I’m not sure how this can be used against the crew. If all options are exhausted, desperation takes over. To use a quote from someone else:
AABusDrvr wrote:
I'll again include this snippet from an airplane operating manual.

"Checklists cannot be created for all conceivable situations and are not intended to replace good judgment.
In some situations, at the captain’s discretion, checklist deviation(s) may be necessary."

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morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:17 pm

Interested wrote:
xmp125a wrote:
morrisond wrote:
Nice - taking partial quotes again and ignoring my comments about training. I have always said it's a training issue.


Being fair to you Morrison - you have been very passionate about pilots all over the world requiring better and more training throughout this debate

How do you feel about Boeing not proposing simulator training for Max ?

Does that not go against everything you want to see improve?


I don't think the MAX specifically needed more training as I see the real problem is lack of hand flying skills and confidence in flying without the nannies.

That being said Boeing really screwed up on MCAS implementation - in design, implementation and training. It should never had the failure mode's that it had.

However it is such a simple procedure to counteract that if it was ever trained in a simulator it would literally be a 2 second training procedure and should be teachable on an iPad.

I don't think a real simulator would have added much to the experience.

If it was in the iPad course before Lionair (and labeleled MCAS - this is what it is and how to counter it) I'm pretty sure Lionair would have been able to continue safely to landing using manual trim. They would not have need to train on it in a sim. They were so close to almost getting it right. If they knew about the existence of MCAS - they saw it and counteracted it properly 22 times - all they had to do was hit the cut-off switches.

I think what would have really helped is if it was added to the iPad course right after Lionair and it be required that Pilot's redo the course before flying the MAX again. But that probably would have taken months to recertify the course and they were changing MCAS anyways once they figure out they screwed up the implementation.

The FCOM supplement should have been enough for any Pilot - assuming they read it - and fully understood it - it should have been top of mind. That was up to the airlines to make sure there Pilots understood it.

MCAS 2.0 will be so benign that if it does trigger - recovery is what you do hundred's of times in a flight - use Electric Trim switches to counteract the new stick forces and put the plane in the proper attitude where MCAS won't trigger.

I am suggesting more simulator training to hone manual flight skills and practicing Non-Normal Procedures. You can practice MCAS 2.0 then - but in terms of emergencies to practice for - it "should" be pretty benign.
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:25 pm

morrisond wrote:
If you couldn't control your airspeed they would never let you out of the sim and into a cockpit.

If you couldn't control your repetitive same argument over and over again, you would never let you of the pilots blame and into the pilots understanding why there where unable to do all the tasks.
 
FluidFlow
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:31 pm

morrisond wrote:
Interested wrote:
xmp125a wrote:


Being fair to you Morrison - you have been very passionate about pilots all over the world requiring better and more training throughout this debate

How do you feel about Boeing not proposing simulator training for Max ?

Does that not go against everything you want to see improve?


I don't think the MAX specifically needed more training as I see the real problem is lack of hand flying skills and confidence in flying without the nannies.

[...]



But is not the main problem of the MAX, that it does not fly like the NG in hand flying mode when all the helpers are off and in my opinion additional simulator training should be warranted for that situation. If not than why train at all different aircraft. At the end they all function the same. There are six degrees of freedom. Keep them under control and every aircraft flies. That works very well in theoretical studies.
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:31 pm

morrisond wrote:
I don't think the MAX specifically needed more training as I see the real problem is lack of hand flying skills and confidence in flying without the nannies.

I think there is a really simple test to prove your assertion wrong. All other things being equal, had they been flying NG instead MAX, this thread wouldn't exist and there wouldn't be two craters in the ground.
 
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:34 pm

PW100 wrote:
The FDR traces show a total of four electric up-trims after MCAS became alive. And ALL FOUR of them stopped at exactly the same pitch trim: 2.3 degrees. Coincidence? Can any crew do such a thing on purpose? I'm having a hard time accepting that.
It must be noted that after take-off, electric trimming was applied several times (both up and down) resulting in a balanced control column. So again, they clearly knew how that works . .


hmmm. you might be on to something here. I do agree, that can't be a coincidence.
 
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PW100
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:39 pm

7BOEING7 wrote:
smartplane wrote:
In the MAX, is the AoA warning light installed in all aircraft delivered, but only enabled if the customer specifically purchases the feature package? In other words, are there cockpits with the warning light installed, but not operative? Is the disagree light fitted to Lion and Ethiopian MAX's?

First it's not a warning light. The AOA DISAGREE alert is an amber alert message that pops up on the PFD (Primary Flight Display) just like the IAS DISAGREE and the ALTITUDE DISAGREE alerts.

In the 737NG it was standard. My understanding is that in the MAX only customers (very few) that bought the AOA Indicator were supposed to get it but there was a mistake by the vendor and nobody got it. After the grounding is lifted everybody will get it whether you purchase the AOA indicator or not.

smartplane wrote:
Boeing CEO is taking the course of least resistance. Enable a feature which is already cabled and ready, to shorten the grounding.


:checkmark:

smartplane wrote:
Some posters clearly need an update from their employer or client, because they earlier claimed enabling the warning light would have made zero difference to the diagnosis or outcome. Standby for a flurry of activity, as earlier posts are edited or deleted.


It wouldn't have made any difference and a 737 pilot for an airline who has written a "737 Technical Manual" he sells for $35 doesn't know for sure either. He's just trying to generate revenue.

The Lion Air captain was in control of the airplane for the most part and neglected to turn off a system that was misbehaving -- if every time you engaged the autopilot it dove for the ground would you continue to engage it? The ET crew with the benefit of the bulletin should have had an even easier time getting the airplane under control but let the airspeed get out of hand.


Thank you for providing some reflection on the "737 Technical Manual" guy. I'm still trying to understand how it would have made a difference. I can see such if the AoA disgree light/message is accompagnied by a separate checklist procedure for AOA DISAGREE. But as far as I understand things correctly, this does not excist. And if created, surely additional training (sim session?) should be provided as well?
Ignoring that something so safety-crtitical van be signalled as "amber alert message". Should it not be a bit more important than just a small amber alert message . . .


With respect to the Lion Air captain not turning the trim system off:
He was facing (severe) pitch control difficulties.
He knew electric pitch trimming was working for him (22 times successful).
Why cut something off that is working for you, when you don't know if there are any other (workable) alternative?

Of course, it is not the best CRM (understatement) not telling the FO this when handing over controls . . .
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morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:41 pm

PW100 wrote:
morrisond wrote:
Interested wrote:
So if you agree with the above isn't that substantial enough to stop worrying about the pilots actions and to focus on what Boeing need to do to stop pilots anywhere in the world facing a similar situation in the future.
. . . .
For sure Morrison if you want these guys trained to use the trim etc let's do it as well. But that's not the real issue here. The Max flawed design has led us to spend weeks analysing and dissecting the ins and outs of something we should never even need to be discussing.


Nice - taking partial quotes again and ignoring my comments about training. I have always said it's a training issue.

You better never fly on an A320 then either as it has a backup trim wheel.

The technical writer said - it might have been saved - there was a lot of hedging in his response. If they had trimmed out the out of trim with Electric before switching it off or never put up the flaps or disengaged TOGA thrust they might have been saved as well.


There is NO evidence that the pilots did not properly use electric trimming. Au contraire, the FDR charts clearly show the use of electric up-trimming being applied many times. So they did understand how that works . . .

The FDR traces show a total of four electric up-trims after MCAS became alive. And ALL FOUR of them stopped at exactly the same pitch trim: 2.3 degrees. Coincidence? Can any crew do such a thing on purpose? I'm having a hard time accepting that.
It must be noted that after take-off, electric trimming was applied several times (both up and down) resulting in a balanced control column. So again, they clearly knew how that works . . .

The cut out switches were flipped before the control column was balanced in pitch. You (again) ASSUME that was by pilot action. We have no evidence of that.

So the question is, a) did up-trimming stop because the cut-out switches were flipped, or b) did they flip the switches because electric up-trimming stopped (uncommandedly) and was not working for them (beyond 2.3 deg Pitch Trim)?
I can’t find that answer in the report nor the FDR traces. You though, seem to have made your mind up already . . .

With respect to the flaps, the pilots could not have known the interaction between flaps up and MCAS waking up. What checklist should they have followed, preventing them from putting up the flaps?



Yes - that is weird about the 2.3 - I think OldAeroGuy or Galaxyflyer yesterday surmised that due to TOGA thrust and Overspeed plus all the Column pressure it overloaded the Trim Motor. - Solution reduce Thrust and it should have returned to normal operation if it wasn't permanently damaged.

The Flap thing has been debated multiple times - NNC for Unreliable airspeed says to not raise flaps or try to engage autopilot or leave autothrottle engaged - all things a big no-no and required memory items.
 
GalaxyFlyer
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:43 pm

XRAYretired wrote:
GalaxyFlyer wrote:
DenverTed wrote:
I read about this idea on Peter Lemme's site, satguru.com. I believe the 'rollercoaster' is for the trim Flinstone power method.


D.P Davies in Handling the Big Jets covered the procedure for trim motor stalling in about 1973 and Boeing instructed long before that. It’s nothing new and it’s not a roller coaster. As I stated, hold the trim switch and release the aerodynamic pressure by relaxing the stick force being applied. If you let the trim position far out of proper, it’s going take some time. Best be aggressive keeping it in trim.

GF

What is the problem with using an oft referred to colloquialism - 'roller coaster' - as a description of a procedure? It was used in Boeing documentation at one point as in the piece attached (facsimile of manual page).

https://theaircurrent.com/aviation-safe ... tigations/


Ray


It’s a media hype word designed to excite and picture it as out of control problem. It’s not.



Gf
 
User avatar
par13del
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:44 pm

PixelFlight wrote:
BOEING DECEIVED THE FAA AND PURCHASERS OF THE BOEING 737-8 MAX BY
ASSERTING THAT CRITICAL SAFETY FEATURES NEED NOT BE STANDARD,
OFFERING THEN ONLY AS OPTIONAL EQUIPMENT AT EXTRA COST

140. Evidence that BOEING put its profits ahead of safety in its design, production, assembly, manufacture, and marketing of the BOEING 737 MAX 8 airplane includes that BOEING charged it customers extra for the installation of important safety features.
[...]
155. BOEING has so completely assumed the FAA certification process that the FAA airworthiness certification of an airplane or airplane system no longer means that the FAA independently considered and determined whether that airplane or airplane system was safe, but rather that BOEING has largely supplemented the role of the FAA. For example: [...]
[... lot of blames about the BOEING lobbying the U.S federal government ...]
BOEING "FIX" AFTER TEH LION AIT CRASH DID NOT WORK
210. Rather than grounding the Boeing 737 MAX 8 until it was fixed and made safe, BOEING chose to prioritize profits over passenger safety, keeping its Boeing 737 MAX 8 airplane in service first after Lion Air and again after subject crash, intentionally misleading its customers, the FAA, passengers and the public that the airplane was safe to fly. Such acts and omissions demonstrate intentional reckless indifference and conscious disregard for the safety of the flying public and Decedent.
[...]
THE PILOTS DID NOT CAUSE THE PLANE TO MALFUNCTION
250. The pilots had completed all the training which BOEING claimed was necessary to operate the aircraft.
251. The pilot(s) on the subject aircraft followed the protocol that had been make known to them as best they could under emergent circumstances, with little altitude and thus little time to troubleshoot and overcome the MCAS system.
[...]
254. The investigations by the air accident investigators to date has not found other cause that interfered with normal operation or caused the crash.
[... no less than 11 counts ...]

Just using this section of your post, why are we still talking about MAX grounding, all Boeing a/c should be grounded, what other safety features in other a/c now flying have they hidden from the FAA and the clients? If they are this bad on the MAX we think they are perfect on other a/c?
If we believe all of what you posted, one would have to question the competence of the governments worldwide who grounded the MAX but continue to allow other Boeing a/c to operate in the jurisdictions
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:50 pm

PW100 wrote:
morrisond wrote:
mjoelnir wrote:
Boeing did practical nothing. They did not explain how MCAS functioned. They did not give out how you recognize and train for MCAS failure mode. They did not fix the simulators so they would show how MCAS works and how it behaves with an AoA failure.
Boeing just pointed to the runaway trim procedure.
Boeing even kept quite over the non existence of the light declaring AoA disagree, pointing exactly at the situation that could produce a MCAS going amok situation. Even if this light should have been a standard feature and being described in the manual.

It is astonishing how you want to leave Boeing of the hook and accuse everybody else.


Please read Page 32-33 of the preliminary crash report - how does that not make the condition clear and show a way to deal with it. This is a different procedure than runaway trim.


We have no evidence they did not carry out the Page 32-33 procedure. Au contraire. They did use the cut-off switches.

I assume you blame the ET crew for two things with respect to this procedure:
A) not using electric trimming to neutralize control column forces;
B) Turning electric trimming back-on, as opposed to the procedure.

A) As I have debated earlier, we have no evidence that electric trimming was stopped by crew action. Further, the text suggesting to neutralize control column before using the cut-out switches, is not an instruction. It is a note. And is says that “electric stabilizer trim CAN be used to . . .” How is that an instruction? IT'S A NOTE, SUGGESTION. And somehow, apparently may have not worked for them.

B) We do have (several) indications that the above was not working out for them, and probably in desperation may have decided to turn electric trimming back on again. I’m not sure how this can be used against the crew. If all options are exhausted, desperation takes over. To use a quote from someone else:
AABusDrvr wrote:
I'll again include this snippet from an airplane operating manual.

"Checklists cannot be created for all conceivable situations and are not intended to replace good judgment.
In some situations, at the captain’s discretion, checklist deviation(s) may be necessary."



I don't think the real reason ET crashed was because they failed to electrically trim out the control forces before switching off - the real issue they needed to correct was leaving it in TOGA thrust where the Manual trim wheels were next to impossible to use out of trim - that made everything harder. It's as bad as leaving it at idle.
Last edited by morrisond on Fri May 31, 2019 2:06 pm, edited 1 time in total.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 1:54 pm

morrisond wrote:
xmp125a wrote:
planecane wrote:
Another video I found from 2015 of a runaway trim in a 737 classic simulator. They cutout the electric trim quickly without really going through the checklist and then trimmed with the wheel. The interesting thing is that disengaging autothrottle and reducing thrust was done by instinct. I can't really tell how out of trim they got but they didn't do a rollercoaster procedure but they did point out the force the copilot was using to hold the column before they got back in trim.

https://www.youtube.com/watch?v=3pPRuFHR1co


1) Classic has larger trim wheels than either NG or max.
2) The MAX simulators (curiously, what about NG ones??) did not realistically simulate forces needed to stabilize out of trim plane using the wheels. MAX simulators did not include MCAS simulation, and did not include proper resistance on trim wheel, I have difficulties believing that they somehow botched this in transition from NG to MAX, so the issue must be older than MAX.

Therefore, it is plausible that the FO on ET flight would be surprised about the resistance he encountered, even if he trained that exact situation in the simulator - his experience would be different in flight than in simulator what is probably the thing you do not want in 1000/hr simulator training!

Again, damning for Boeing.


And again you ignore the fact that thrust was left at TOGA and they were above Vmo. It's like faulting Boeing for the plane falling out of the sky at 40knots below stall speed.


Exactly. I tried to point out that in that simulation in a classic simulator in 2015, the first reaction of the pilot/instructor was to tell the FO to turn off the cutoff switches (and he switched both even though they used to be for two different things). Then he commands autothrottle off and then says to slow down a little and reduces thrust. I will never be able to understand why the pilots of the 2 crashed MAXs wouldn't have done these steps out of instinct, regardless of what the root cause was and regardless of the semantics of the word "continuisly." It seems from videos made years before the MAX took flight that these things were part of training to fly a 737.

The only explanation is that there are issues with the training these crews were given. I don't believe that "third world pilots" are somehow unskilled. I do believe that if they had been trained well, they would have recovered from the MCAS issue.

Training (not just simulator training for MCAS) must be addressed in response to these crashes.

Note: I'm not absolving Boeing for creating a new failure cause with an unacceptable failure rate.
 
Elementalism
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:02 pm

TOGA made a difficult situation nearly impossible to recover. The speed made using the manual trim nearly if not impossible. And even if they knew about the roller coaster procedure to trim, they lacked altitude to use it.

This situation will be used going forward by manufacturers and regulators for what not to do when implementing what should be a relatively benign system. I'm still shocked anybody at Boeing thought it wise to allow this system to put the plane into a full trim down position. MCAS 2.0 is what 1.0 should had been. And both of those crashes would never had happened.
 
xmp125a
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:05 pm

planecane wrote:
I will never be able to understand why the pilots of the 2 crashed MAXs wouldn't have done these steps out of instinct, regardless of what the root cause was and regardless of the semantics of the word "continuisly." It seems from videos made years before the MAX took flight that these things were part of training to fly a 737.


One of the first things Boeing admitted was that they put the pilot under far too great amount of pressure with all the conflicting alarms going off left and right + plane got suicidal. There is a limit how much human brain can process at a time. Which leads us back: if you design such a stupid system like MCAS 1.0, and a minor flaw makes plane fly into the ground, this could be simply solved by aural warning "AoA sensors disagreement" and other alerts supressed. Because THAT was the core problem, but they were faced with circus of deceiving alerts going on.
 
kalvado
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:10 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:

Please read Page 32-33 of the preliminary crash report - how does that not make the condition clear and show a way to deal with it. This is a different procedure than runaway trim.


We have no evidence they did not carry out the Page 32-33 procedure. Au contraire. They did use the cut-off switches.

I assume you blame the ET crew for two things with respect to this procedure:
A) not using electric trimming to neutralize control column forces;
B) Turning electric trimming back-on, as opposed to the procedure.

A) As I have debated earlier, we have no evidence that electric trimming was stopped by crew action. Further, the text suggesting to neutralize control column before using the cut-out switches, is not an instruction. It is a note. And is says that “electric stabilizer trim CAN be used to . . .” How is that an instruction? IT'S A NOTE, SUGGESTION. And somehow, apparently may have not worked for them.

B) We do have (several) indications that the above was not working out for them, and probably in desperation may have decided to turn electric trimming back on again. I’m not sure how this can be used against the crew. If all options are exhausted, desperation takes over. To use a quote from someone else:
AABusDrvr wrote:
I'll again include this snippet from an airplane operating manual.

"Checklists cannot be created for all conceivable situations and are not intended to replace good judgment.
In some situations, at the captain’s discretion, checklist deviation(s) may be necessary."



I don't think the real reason ET crashed was because they failed to electrically trim out the control forces before switching off - the real issue they needed to correct was leaving it in TOGA thrust where the Manual trim wheels were next to impossible to use out of trim - that made everything harder. It's as bad as leaving it at idle.

The real root cause issue is lack of training clearly seen in Boeing and FAA engineering... But thats the problem of educational system, after all.
 
kalvado
Posts: 2008
Joined: Wed Mar 01, 2006 4:29 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:18 pm

par13del wrote:
Just using this section of your post, why are we still talking about MAX grounding, all Boeing a/c should be grounded, what other safety features in other a/c now flying have they hidden from the FAA and the clients? If they are this bad on the MAX we think they are perfect on other a/c?
If we believe all of what you posted, one would have to question the competence of the governments worldwide who grounded the MAX but continue to allow other Boeing a/c to operate in the jurisdictions

unlike humans being sent to jail, airplane grounding is not a punitive action - the main goal of grounding is to prevent accidents from a known cause which may occur before the fix is done. If probability exceeds certain threshold, then grounding is warranted. There is no indication that whatever shortcuts were taken on other Boeing models, they are significant accident factors. (Side note: I don't really understand the logic of prison term used as a punishment for a crime. But that is a completely different story)
With that, NG review is being done - and I fully expect some modifications to NG being required. 777x certification will be a fun ride for Boeing, though, with any suspected corner cutting being examined and zero leniencies applied to process.
 
morrisond
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Joined: Thu Jan 07, 2010 12:22 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:33 pm

FluidFlow wrote:
morrisond wrote:
Interested wrote:

Being fair to you Morrison - you have been very passionate about pilots all over the world requiring better and more training throughout this debate

How do you feel about Boeing not proposing simulator training for Max ?

Does that not go against everything you want to see improve?


I don't think the MAX specifically needed more training as I see the real problem is lack of hand flying skills and confidence in flying without the nannies.

[...]



But is not the main problem of the MAX, that it does not fly like the NG in hand flying mode when all the helpers are off and in my opinion additional simulator training should be warranted for that situation. If not than why train at all different aircraft. At the end they all function the same. There are six degrees of freedom. Keep them under control and every aircraft flies. That works very well in theoretical studies.


In retrospect - I think Boeing should have gone for this approach - They should have skipped MCAS all together - apply for an exception on the stick force gradient and just required some SIM time to show that the control forces get a little light at far aft COG and light weights.

It should not have been a big deal for any pilot and taken 5 minutes in a SIM.
 
XRAYretired
Posts: 623
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:35 pm

morrisond wrote:
PW100 wrote:
morrisond wrote:

Nice - taking partial quotes again and ignoring my comments about training. I have always said it's a training issue.

You better never fly on an A320 then either as it has a backup trim wheel.

The technical writer said - it might have been saved - there was a lot of hedging in his response. If they had trimmed out the out of trim with Electric before switching it off or never put up the flaps or disengaged TOGA thrust they might have been saved as well.


There is NO evidence that the pilots did not properly use electric trimming. Au contraire, the FDR charts clearly show the use of electric up-trimming being applied many times. So they did understand how that works . . .

The FDR traces show a total of four electric up-trims after MCAS became alive. And ALL FOUR of them stopped at exactly the same pitch trim: 2.3 degrees. Coincidence? Can any crew do such a thing on purpose? I'm having a hard time accepting that.
It must be noted that after take-off, electric trimming was applied several times (both up and down) resulting in a balanced control column. So again, they clearly knew how that works . . .

The cut out switches were flipped before the control column was balanced in pitch. You (again) ASSUME that was by pilot action. We have no evidence of that.

So the question is, a) did up-trimming stop because the cut-out switches were flipped, or b) did they flip the switches because electric up-trimming stopped (uncommandedly) and was not working for them (beyond 2.3 deg Pitch Trim)?
I can’t find that answer in the report nor the FDR traces. You though, seem to have made your mind up already . . .

With respect to the flaps, the pilots could not have known the interaction between flaps up and MCAS waking up. What checklist should they have followed, preventing them from putting up the flaps?



Yes - that is weird about the 2.3 - I think OldAeroGuy or Galaxyflyer yesterday surmised that due to TOGA thrust and Overspeed plus all the Column pressure it overloaded the Trim Motor. - Solution reduce Thrust and it should have returned to normal operation if it wasn't permanently damaged.

The Flap thing has been debated multiple times - NNC for Unreliable airspeed says to not raise flaps or try to engage autopilot or leave autothrottle engaged - all things a big no-no and required memory items.


10.1 Airspeed Unreliable
NNC.10 Non-Normal Checklists-Flight Instruments, Displays
1 Adjust the airplane attitude and thrust. Maintain airplane control.
2 PROBE HEAT switches. - Check ON
3 Cross check the MACH/AIRSPEED indicators.
4 Cross check the IRS and FMC ground speed and winds to determine airspeed accuracy if indicated airspeed is questionable.
5 Attitude and thrust information is located in the Performance Inflight section.737-800 Performance Inflight - QRH Chapter PI-QRH General

Section 10
QRH.10.1
PI-QRH.10 Performance Inflight - QRH-General General Flight With Unreliable Airspeed/ TurbulentAirPenetration Altitude and/or vertical speed indications may also be unreliable.
Climb (280/.76) Flaps Up, Set Max Climb Thrust
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:43 pm

GalaxyFlyer wrote:
XRAYretired wrote:
GalaxyFlyer wrote:

D.P Davies in Handling the Big Jets covered the procedure for trim motor stalling in about 1973 and Boeing instructed long before that. It’s nothing new and it’s not a roller coaster. As I stated, hold the trim switch and release the aerodynamic pressure by relaxing the stick force being applied. If you let the trim position far out of proper, it’s going take some time. Best be aggressive keeping it in trim.

GF

What is the problem with using an oft referred to colloquialism - 'roller coaster' - as a description of a procedure? It was used in Boeing documentation at one point as in the piece attached (facsimile of manual page).

https://theaircurrent.com/aviation-safe ... tigations/


Ray


It’s a media hype word designed to excite and picture it as out of control problem. It’s not.



Gf

Its used in the Boeing document. So no reason not to use it descriptively.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 2:48 pm

kalvado wrote:
par13del wrote:
Just using this section of your post, why are we still talking about MAX grounding, all Boeing a/c should be grounded, what other safety features in other a/c now flying have they hidden from the FAA and the clients? If they are this bad on the MAX we think they are perfect on other a/c?
If we believe all of what you posted, one would have to question the competence of the governments worldwide who grounded the MAX but continue to allow other Boeing a/c to operate in the jurisdictions

unlike humans being sent to jail, airplane grounding is not a punitive action - the main goal of grounding is to prevent accidents from a known cause which may occur before the fix is done. If probability exceeds certain threshold, then grounding is warranted. There is no indication that whatever shortcuts were taken on other Boeing models, they are significant accident factors. (Side note: I don't really understand the logic of prison term used as a punishment for a crime. But that is a completely different story)
With that, NG review is being done - and I fully expect some modifications to NG being required. 777x certification will be a fun ride for Boeing, though, with any suspected corner cutting being examined and zero leniencies applied to process.

I think the logic of a prison term as punishment is that things like cutting off a thief's hands is a little inhumane so society needed to come up with something that should be undesirable. At the same time, the person is unable to commit more crimes (at least physically) while incarcerated. [/Off topic]
 
GalaxyFlyer
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 3:07 pm

morrisond wrote:
FluidFlow wrote:
morrisond wrote:

I don't think the MAX specifically needed more training as I see the real problem is lack of hand flying skills and confidence in flying without the nannies.

[...]



But is not the main problem of the MAX, that it does not fly like the NG in hand flying mode when all the helpers are off and in my opinion additional simulator training should be warranted for that situation. If not than why train at all different aircraft. At the end they all function the same. There are six degrees of freedom. Keep them under control and every aircraft flies. That works very well in theoretical studies.


In retrospect - I think Boeing should have gone for this approach - They should have skipped MCAS all together - apply for an exception on the stick force gradient and just required some SIM time to show that the control forces get a little light at far aft COG and light weights.

It should not have been a big deal for any pilot and taken 5 minutes in a SIM.


Wouldn’t met FAR 25 stall characteristics, so a no go. They needed to man up, describe the aerodynamics involved and recommend training. As Feynman said, “For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.”

GF
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 3:09 pm

planecane wrote:
morrisond wrote:
xmp125a wrote:

1) Classic has larger trim wheels than either NG or max.
2) The MAX simulators (curiously, what about NG ones??) did not realistically simulate forces needed to stabilize out of trim plane using the wheels. MAX simulators did not include MCAS simulation, and did not include proper resistance on trim wheel, I have difficulties believing that they somehow botched this in transition from NG to MAX, so the issue must be older than MAX.

Therefore, it is plausible that the FO on ET flight would be surprised about the resistance he encountered, even if he trained that exact situation in the simulator - his experience would be different in flight than in simulator what is probably the thing you do not want in 1000/hr simulator training!

Again, damning for Boeing.


And again you ignore the fact that thrust was left at TOGA and they were above Vmo. It's like faulting Boeing for the plane falling out of the sky at 40knots below stall speed.


Exactly. I tried to point out that in that simulation in a classic simulator in 2015, the first reaction of the pilot/instructor was to tell the FO to turn off the cutoff switches (and he switched both even though they used to be for two different things). Then he commands autothrottle off and then says to slow down a little and reduces thrust. I will never be able to understand why the pilots of the 2 crashed MAXs wouldn't have done these steps out of instinct, regardless of what the root cause was and regardless of the semantics of the word "continuisly." It seems from videos made years before the MAX took flight that these things were part of training to fly a 737.

The only explanation is that there are issues with the training these crews were given. I don't believe that "third world pilots" are somehow unskilled. I do believe that if they had been trained well, they would have recovered from the MCAS issue.

Training (not just simulator training for MCAS) must be addressed in response to these crashes.

Note: I'm not absolving Boeing for creating a new failure cause with an unacceptable failure rate.

I assume the simulator set up was low altitude, initial climb, Airspeed Unreliable, Altitude Unreliable, single side Stick Shaker, then unexpected nose down trim. Otherwise its apples and bananas.

Ray
 
morrisond
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 3:31 pm

XRAYretired wrote:
morrisond wrote:
PW100 wrote:

There is NO evidence that the pilots did not properly use electric trimming. Au contraire, the FDR charts clearly show the use of electric up-trimming being applied many times. So they did understand how that works . . .

The FDR traces show a total of four electric up-trims after MCAS became alive. And ALL FOUR of them stopped at exactly the same pitch trim: 2.3 degrees. Coincidence? Can any crew do such a thing on purpose? I'm having a hard time accepting that.
It must be noted that after take-off, electric trimming was applied several times (both up and down) resulting in a balanced control column. So again, they clearly knew how that works . . .

The cut out switches were flipped before the control column was balanced in pitch. You (again) ASSUME that was by pilot action. We have no evidence of that.

So the question is, a) did up-trimming stop because the cut-out switches were flipped, or b) did they flip the switches because electric up-trimming stopped (uncommandedly) and was not working for them (beyond 2.3 deg Pitch Trim)?
I can’t find that answer in the report nor the FDR traces. You though, seem to have made your mind up already . . .

With respect to the flaps, the pilots could not have known the interaction between flaps up and MCAS waking up. What checklist should they have followed, preventing them from putting up the flaps?



Yes - that is weird about the 2.3 - I think OldAeroGuy or Galaxyflyer yesterday surmised that due to TOGA thrust and Overspeed plus all the Column pressure it overloaded the Trim Motor. - Solution reduce Thrust and it should have returned to normal operation if it wasn't permanently damaged.

The Flap thing has been debated multiple times - NNC for Unreliable airspeed says to not raise flaps or try to engage autopilot or leave autothrottle engaged - all things a big no-no and required memory items.


10.1 Airspeed Unreliable
NNC.10 Non-Normal Checklists-Flight Instruments, Displays
1 Adjust the airplane attitude and thrust. Maintain airplane control.
2 PROBE HEAT switches. - Check ON
3 Cross check the MACH/AIRSPEED indicators.
4 Cross check the IRS and FMC ground speed and winds to determine airspeed accuracy if indicated airspeed is questionable.
5 Attitude and thrust information is located in the Performance Inflight section.737-800 Performance Inflight - QRH Chapter PI-QRH General

Section 10
QRH.10.1
PI-QRH.10 Performance Inflight - QRH-General General Flight With Unreliable Airspeed/ TurbulentAirPenetration Altitude and/or vertical speed indications may also be unreliable.
Climb (280/.76) Flaps Up, Set Max Climb Thrust


Sorry - I wasn't thinking of the right checklist - others have posted it many times - was it the AOA failure checklist?
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 3:48 pm

XRAYretired wrote:
planecane wrote:
morrisond wrote:

And again you ignore the fact that thrust was left at TOGA and they were above Vmo. It's like faulting Boeing for the plane falling out of the sky at 40knots below stall speed.


Exactly. I tried to point out that in that simulation in a classic simulator in 2015, the first reaction of the pilot/instructor was to tell the FO to turn off the cutoff switches (and he switched both even though they used to be for two different things). Then he commands autothrottle off and then says to slow down a little and reduces thrust. I will never be able to understand why the pilots of the 2 crashed MAXs wouldn't have done these steps out of instinct, regardless of what the root cause was and regardless of the semantics of the word "continuisly." It seems from videos made years before the MAX took flight that these things were part of training to fly a 737.

The only explanation is that there are issues with the training these crews were given. I don't believe that "third world pilots" are somehow unskilled. I do believe that if they had been trained well, they would have recovered from the MCAS issue.

Training (not just simulator training for MCAS) must be addressed in response to these crashes.

Note: I'm not absolving Boeing for creating a new failure cause with an unacceptable failure rate.

I assume the simulator set up was low altitude, initial climb, Airspeed Unreliable, Altitude Unreliable, single side Stick Shaker, then unexpected nose down trim. Otherwise its apples and bananas.

Ray


It wasn't. However, from the information available, the ET crew didn't address any of the items in your list except for the runaway stabilizer. If that is what they were attempting to correct, the other items shouldn't have effected the actions taken for runaway stabilizer. The preliminary report may have left out parts of the CVR info but you'd think they'd have included that.

Without CVR information we can't say for sure what the lion air crew was addressing.
 
User avatar
par13del
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 3:49 pm

kalvado wrote:
unlike humans being sent to jail, airplane grounding is not a punitive action - the main goal of grounding is to prevent accidents from a known cause which may occur before the fix is done. If probability exceeds certain threshold, then grounding is warranted. There is no indication that whatever shortcuts were taken on other Boeing models, they are significant accident factors. (Side note: I don't really understand the logic of prison term used as a punishment for a crime. But that is a completely different story)
With that, NG review is being done - and I fully expect some modifications to NG being required. 777x certification will be a fun ride for Boeing, though, with any suspected corner cutting being examined and zero leniencies applied to process.

Suggest you reread his post and others who put out such rhetoric, if the management of Boeing is greedy, have blood on their hands, etc etc etc it will not be specific to the MAX, if he really believes everything he post, he should be screaming to high heaven to have all Boeing a/c grounded until they can all be reviewed, after all, does he want to wait until other a/c start falling out of the air?

As I said earlier, we need to tone down the rhetoric, we can certainly ignore but as other have said, the optics are not good.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 3:54 pm

XRAYretired wrote:
GalaxyFlyer wrote:
XRAYretired wrote:
What is the problem with using an oft referred to colloquialism - 'roller coaster' - as a description of a procedure? It was used in Boeing documentation at one point as in the piece attached (facsimile of manual page).

https://theaircurrent.com/aviation-safe ... tigations/


Ray


It’s a media hype word designed to excite and picture it as out of control problem. It’s not.



Gf

Its used in the Boeing document. So no reason not to use it descriptively.


Do the detailed instructions for emergency procedures still exist in any document for any of the procedures? Basically, I'm trying to figure out if they removed the roller coaster procedure documentation specifically or if they depracated that entire document or section of the document it was in. I don't believe it was ever part of the checklist.
 
kalvado
Posts: 2008
Joined: Wed Mar 01, 2006 4:29 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 4:02 pm

par13del wrote:
kalvado wrote:
unlike humans being sent to jail, airplane grounding is not a punitive action - the main goal of grounding is to prevent accidents from a known cause which may occur before the fix is done. If probability exceeds certain threshold, then grounding is warranted. There is no indication that whatever shortcuts were taken on other Boeing models, they are significant accident factors. (Side note: I don't really understand the logic of prison term used as a punishment for a crime. But that is a completely different story)
With that, NG review is being done - and I fully expect some modifications to NG being required. 777x certification will be a fun ride for Boeing, though, with any suspected corner cutting being examined and zero leniencies applied to process.

Suggest you reread his post and others who put out such rhetoric, if the management of Boeing is greedy, have blood on their hands, etc etc etc it will not be specific to the MAX, if he really believes everything he post, he should be screaming to high heaven to have all Boeing a/c grounded until they can all be reviewed, after all, does he want to wait until other a/c start falling out of the air?

As I said earlier, we need to tone down the rhetoric, we can certainly ignore but as other have said, the optics are not good.

There is no such thing as engineer getting all resources they want, and in hindsight critical mistakes are easy to spot - while non-critical ones seem minor. One can think about that last straw that broke camel's back, and (armed with a perfect hindsight!) we can tell MCAS was a mistake. If (and hopefully not!) 787 crashes this weekend because of design shortcut, there would be a good chance to practice hindsight again with Boeing bashing extending beyond any limit...
Anyway, I am always willing to assume that any technical mistake is an honest one, even if it is stupid. Everyone knows failure can be costly, nobody plans for the failure on purpose... To uphold honest mistake assumption though, recognition of error and embracing into corrective action is a must. SOmething Boeing is not too willing to do - hence loosing benefit of doubt.
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 4:24 pm

morrisond wrote:
XRAYretired wrote:
morrisond wrote:


Yes - that is weird about the 2.3 - I think OldAeroGuy or Galaxyflyer yesterday surmised that due to TOGA thrust and Overspeed plus all the Column pressure it overloaded the Trim Motor. - Solution reduce Thrust and it should have returned to normal operation if it wasn't permanently damaged.

The Flap thing has been debated multiple times - NNC for Unreliable airspeed says to not raise flaps or try to engage autopilot or leave autothrottle engaged - all things a big no-no and required memory items.


10.1 Airspeed Unreliable
NNC.10 Non-Normal Checklists-Flight Instruments, Displays
1 Adjust the airplane attitude and thrust. Maintain airplane control.
2 PROBE HEAT switches. - Check ON
3 Cross check the MACH/AIRSPEED indicators.
4 Cross check the IRS and FMC ground speed and winds to determine airspeed accuracy if indicated airspeed is questionable.
5 Attitude and thrust information is located in the Performance Inflight section.737-800 Performance Inflight - QRH Chapter PI-QRH General

Section 10
QRH.10.1
PI-QRH.10 Performance Inflight - QRH-General General Flight With Unreliable Airspeed/ TurbulentAirPenetration Altitude and/or vertical speed indications may also be unreliable.
Climb (280/.76) Flaps Up, Set Max Climb Thrust


Sorry - I wasn't thinking of the right checklist - others have posted it many times - was it the AOA failure checklist?

AOA Disagree was not available of course cos not paid for:

10.2 AOA DISAGREE
1 Airspeed errors and the IAS DISAGREE alert may occur.
2 Altimeter errors and the ALT DISAGREE alert may occur.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 4:27 pm

PW100 wrote:
morrisond wrote:
Interested wrote:
So if you agree with the above isn't that substantial enough to stop worrying about the pilots actions and to focus on what Boeing need to do to stop pilots anywhere in the world facing a similar situation in the future.
. . . .
For sure Morrison if you want these guys trained to use the trim etc let's do it as well. But that's not the real issue here. The Max flawed design has led us to spend weeks analysing and dissecting the ins and outs of something we should never even need to be discussing.


Nice - taking partial quotes again and ignoring my comments about training. I have always said it's a training issue.

You better never fly on an A320 then either as it has a backup trim wheel.

The technical writer said - it might have been saved - there was a lot of hedging in his response. If they had trimmed out the out of trim with Electric before switching it off or never put up the flaps or disengaged TOGA thrust they might have been saved as well.


There is NO evidence that the pilots did not properly use electric trimming. Au contraire, the FDR charts clearly show the use of electric up-trimming being applied many times. So they did understand how that works . . .

The FDR traces show a total of four electric up-trims after MCAS became alive. And ALL FOUR of them stopped at exactly the same pitch trim: 2.3 degrees. Coincidence? Can any crew do such a thing on purpose? I'm having a hard time accepting that.
It must be noted that after take-off, electric trimming was applied several times (both up and down) resulting in a balanced control column. So again, they clearly knew how that works . . .

The cut out switches were flipped before the control column was balanced in pitch. You (again) ASSUME that was by pilot action. We have no evidence of that.

So the question is, a) did up-trimming stop because the cut-out switches were flipped, or b) did they flip the switches because electric up-trimming stopped (uncommandedly) and was not working for them (beyond 2.3 deg Pitch Trim)?
I can’t find that answer in the report nor the FDR traces. You though, seem to have made your mind up already . . .

With respect to the flaps, the pilots could not have known the interaction between flaps up and MCAS waking up. What checklist should they have followed, preventing them from putting up the flaps?


You are developing a bit of tunnel vision on the trim stopping at 2.3 units. It is certainly something that should be looked at and it will be helpful if the CVR analysis is able to hear exactly when the switches were flipped.

That said, the fact that the command stopped exactly when the trim stopped changing would indicate that the stabilizer stopped moving because either the switches were cut out or the thumb switch was no longer being depressed. The fact that MCAS kicked in 5 seconds after the command was no longer on the FDR traces indicates that the FCC wasn't seeing the command simultaneously with the DFDR no longer recording it.

I won't completely discount your theory until more evidence is available, but from what we are able to see it would appear that the manual uptrim ceased due to pilot actions.
 
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PixelFlight
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 4:32 pm

par13del wrote:
PixelFlight wrote:
BOEING DECEIVED THE FAA AND PURCHASERS OF THE BOEING 737-8 MAX BY
ASSERTING THAT CRITICAL SAFETY FEATURES NEED NOT BE STANDARD,
OFFERING THEN ONLY AS OPTIONAL EQUIPMENT AT EXTRA COST

140. Evidence that BOEING put its profits ahead of safety in its design, production, assembly, manufacture, and marketing of the BOEING 737 MAX 8 airplane includes that BOEING charged it customers extra for the installation of important safety features.
[...]
155. BOEING has so completely assumed the FAA certification process that the FAA airworthiness certification of an airplane or airplane system no longer means that the FAA independently considered and determined whether that airplane or airplane system was safe, but rather that BOEING has largely supplemented the role of the FAA. For example: [...]
[... lot of blames about the BOEING lobbying the U.S federal government ...]
BOEING "FIX" AFTER TEH LION AIT CRASH DID NOT WORK
210. Rather than grounding the Boeing 737 MAX 8 until it was fixed and made safe, BOEING chose to prioritize profits over passenger safety, keeping its Boeing 737 MAX 8 airplane in service first after Lion Air and again after subject crash, intentionally misleading its customers, the FAA, passengers and the public that the airplane was safe to fly. Such acts and omissions demonstrate intentional reckless indifference and conscious disregard for the safety of the flying public and Decedent.
[...]
THE PILOTS DID NOT CAUSE THE PLANE TO MALFUNCTION
250. The pilots had completed all the training which BOEING claimed was necessary to operate the aircraft.
251. The pilot(s) on the subject aircraft followed the protocol that had been make known to them as best they could under emergent circumstances, with little altitude and thus little time to troubleshoot and overcome the MCAS system.
[...]
254. The investigations by the air accident investigators to date has not found other cause that interfered with normal operation or caused the crash.
[... no less than 11 counts ...]

Just using this section of your post, why are we still talking about MAX grounding, all Boeing a/c should be grounded, what other safety features in other a/c now flying have they hidden from the FAA and the clients? If they are this bad on the MAX we think they are perfect on other a/c?
If we believe all of what you posted, one would have to question the competence of the governments worldwide who grounded the MAX but continue to allow other Boeing a/c to operate in the jurisdictions

Well, that partial text from the document is yet an other piece of the very complicated puzzle. It just show how some will defend there perception with legal tools. What I found more interesting is the increasing gap between that kind of view that tend to be more and more legal and official, and the "pilot blame" view that is manly confined to a minority of contributors in public forums. Last time pilots was blamed from a public figure it triggered a load of protest from pilots association. Yet nobody seem to have attacked Lion Air and/or Ethiopian Airline with legal tools. While this is not a definitive situation, I can't see how an hypothetical escalation of that kind will not hurt back Boeing even more hard.

Without doubt, this is one of the major crisis in civil aircraft industry that raise very important and disturbing questions about safety on all levels. The whole picture look incoherent and maybe nobody is actually certain that the picture is yet complete. This industry need to recover a coherent perception of safety. This will be hard. In that context I can't understand why some still insists so repetitively to blame the killed pilots. This is completely against a constructive solution of the problem. As for the Boeing 737 lineup safety it's Boeing own interest to fix all that can goes wrong. This probably imply to walk away from grandfathering certification.
 
kalvado
Posts: 2008
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 4:44 pm

PixelFlight wrote:

Without doubt, this is one of the major crisis in civil aircraft industry that raise very important and disturbing questions about safety on all levels. The whole picture look incoherent and maybe nobody is actually certain that the picture is yet complete. This industry need to recover a coherent perception of safety. This will be hard. In that context I can't understand why some still insists so repetitively to blame the killed pilots. This is completely against a constructive solution of the problem. As for the Boeing 737 lineup safety it's Boeing own interest to fix all that can goes wrong. This probably imply to walk away from grandfathering certification.

Walking away from grandfathered certification is a huge assumption. You cannot certify 737 on modern requirements, and certification requirements are frozen to a design start date or so.
Moreover, NG has a huge safety record, and building up on that record is a huge benefit in terms of safety as many issues are resolved and solutions are proven by decades of service. Totally new design can have it newly born gremlins...
Relaxing use of grandfathering rights may be a better wording..
 
DenverTed
Posts: 258
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 4:59 pm

PixelFlight wrote:

139, In BOEING's rush to get the 737 MAX 8 to market, BOEING knowingly, intentionally, wantonly, callously, egregiously, negligently, and possibly criminally, compromised and endangered the safety of BOEING 737 MAX 8 crews and passengers, and killed two plane loads of people.

Don't forget carelessly, cavalierly, and possibly cantankerously.
 
planecane
Posts: 1138
Joined: Thu Feb 09, 2017 4:58 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 5:27 pm

PixelFlight wrote:
Interested wrote:
According to the lawsuit reported in this article - the same tactics to hide design flaws and deflect blame onto the pilots have been used on previous Boeing crashes

https://www.cnn.com/2019/05/21/politics ... index.html

From the document:
109. BOEING intentionally designed the MCAS to take data from one of the 737 MAX 8's two angle of attack (AOA) sensors and to alternate the sensor from which it accepts data each flight.
110. BOEING hos not publicly disclosed why it decided to have the MCAS take data from only one indicator,
[...]
113. Even though Rockwell Collins (Collins Aerospace) build the 737 MAX 8 flight control computer and the software and coding that run the MCAS, and Rosemount manufactured and supplied the Angle of Attack indicator, BOEING remains responsible for its suppliers and contractors, and for the design, production, manufacture, certification and airworthiness of its BOEING aircraft,
114. Rockwell Collins witch produced the flight controls computers and software on the 737 MAX 8 also provided software update to BOEING after the crash of Lion Air in 2018, but BOEING has not taken the necessary action to make all changes needed on 737 MAX 8 and the subject aircraft before the crash of Ethiopian Airlines Flight 302.
[... lot of blames on BOEING ...]
134. As a result of BOEING's intentional and knowing decisions, the pilots of the subject aircraft had not received any simulator training or testing on how to handle emergencies caused by the BOEING 737 MAX 8 airplane's MCAS.
135. BOEING knowingly failed to conduct a proper failure mode and effect analysis during development of the BOEING 737-8 MAX to ensure that the airplane's MCAS was safe.
[...]
139, In BOEING's rush to get the 737 MAX 8 to market, BOEING knowingly, intentionally, wantonly, callously, egregiously, negligently, and possibly criminally, compromised and endangered the safety of BOEING 737 MAX 8 crews and passengers, and killed two plane loads of people.

BOEING DECEIVED THE FAA AND PURCHASERS OF THE BOEING 737-8 MAX BY
ASSERTING THAT CRITICAL SAFETY FEATURES NEED NOT BE STANDARD,
OFFERING THEN ONLY AS OPTIONAL EQUIPMENT AT EXTRA COST

140. Evidence that BOEING put its profits ahead of safety in its design, production, assembly, manufacture, and marketing of the BOEING 737 MAX 8 airplane includes that BOEING charged it customers extra for the installation of important safety features.
[...]
155. BOEING has so completely assumed the FAA certification process that the FAA airworthiness certification of an airplane or airplane system no longer means that the FAA independently considered and determined whether that airplane or airplane system was safe, but rather that BOEING has largely supplemented the role of the FAA. For example: [...]
[... lot of blames about the BOEING lobbying the U.S federal government ...]
BOEING "FIX" AFTER TEH LION AIT CRASH DID NOT WORK
210. Rather than grounding the Boeing 737 MAX 8 until it was fixed and made safe, BOEING chose to prioritize profits over passenger safety, keeping its Boeing 737 MAX 8 airplane in service first after Lion Air and again after subject crash, intentionally misleading its customers, the FAA, passengers and the public that the airplane was safe to fly. Such acts and omissions demonstrate intentional reckless indifference and conscious disregard for the safety of the flying public and Decedent.
[...]
THE PILOTS DID NOT CAUSE THE PLANE TO MALFUNCTION
250. The pilots had completed all the training which BOEING claimed was necessary to operate the aircraft.
251. The pilot(s) on the subject aircraft followed the protocol that had been make known to them as best they could under emergent circumstances, with little altitude and thus little time to troubleshoot and overcome the MCAS system.
[...]
254. The investigations by the air accident investigators to date has not found other cause that interfered with normal operation or caused the crash.
[... no less than 11 counts ...]


You do understand that these are plaintiff claims and not the result of an independent investigation, right? The 11 counts are a plaintiff's attorney putting as many as he can come up with so that if some are not proven there will be others for the jury to award damages for. These are not like counts in a criminal case where law enforcement gathered evidence supporting all charges.

A neighbor of mine was sued for an automobile accident (later found not liable by a jury) and it had 17 counts in it.

A plaintiff's attorney making your arguments doesn't prove them correct.
 
XRAYretired
Posts: 623
Joined: Fri Mar 15, 2019 11:21 am

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 5:27 pm

planecane wrote:
XRAYretired wrote:
GalaxyFlyer wrote:

It’s a media hype word designed to excite and picture it as out of control problem. It’s not.



Gf

Its used in the Boeing document. So no reason not to use it descriptively.


Do the detailed instructions for emergency procedures still exist in any document for any of the procedures? Basically, I'm trying to figure out if they removed the roller coaster procedure documentation specifically or if they depracated that entire document or section of the document it was in. I don't believe it was ever part of the checklist.

All we have open source is a couple of reporters saying it was deleted from the manuals.

Ray
 
planecane
Posts: 1138
Joined: Thu Feb 09, 2017 4:58 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 5:50 pm

XRAYretired wrote:
planecane wrote:
XRAYretired wrote:
Its used in the Boeing document. So no reason not to use it descriptively.


Do the detailed instructions for emergency procedures still exist in any document for any of the procedures? Basically, I'm trying to figure out if they removed the roller coaster procedure documentation specifically or if they depracated that entire document or section of the document it was in. I don't believe it was ever part of the checklist.

All we have open source is a couple of reporters saying it was deleted from the manuals.

Ray


What manual was it in to begin with? The FCOM or something else? All I have seen is the scan of the page.
 
planecane
Posts: 1138
Joined: Thu Feb 09, 2017 4:58 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 5:57 pm

planecane wrote:
XRAYretired wrote:
planecane wrote:

Do the detailed instructions for emergency procedures still exist in any document for any of the procedures? Basically, I'm trying to figure out if they removed the roller coaster procedure documentation specifically or if they depracated that entire document or section of the document it was in. I don't believe it was ever part of the checklist.

All we have open source is a couple of reporters saying it was deleted from the manuals.

Ray


What manual was it in to begin with? The FCOM or something else? All I have seen is the scan of the page.


Ok I found it. It was the flight crew training manual. It wasn't exactly removed, but described in a different way. This is from an NG training manual I found online.

Excessive airloads on the stabilizer may require effort by both pilots to correct the
mis-trim. In extreme cases it may be necessary to aerodynamically relieve the
airloads to allow manual trimming. Accelerate or decelerate towards the in-trim
speed while attempting to trim manually.
 
DenverTed
Posts: 258
Joined: Wed Mar 27, 2019 11:12 pm

Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 6:11 pm

planecane wrote:

Ok I found it. It was the flight crew training manual. It wasn't exactly removed, but described in a different way. This is from an NG training manual I found online.

Excessive airloads on the stabilizer may require effort by both pilots to correct the
mis-trim. In extreme cases it may be necessary to aerodynamically relieve the
airloads to allow manual trimming. Accelerate or decelerate towards the in-trim
speed while attempting to trim manually.

"effort by both pilots"? That's vague. Does that imply they are both supposed to turn the manual trim wheel or not? That should be definitively stated by Boeing in revised literature required by the ungrounding, IMO.

Accel or decel? This sounds like a different approach than the 'fishing pole' (yoyo rollercoaster) approach of relieving winding pressure by changing elevator input.
 
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AirlineCritic
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Re: Boeing 737MAX Grounded Worldwide Q2 2019

Fri May 31, 2019 6:13 pm

sillystrings wrote:
morrisond wrote:
I don't think the MAX specifically needed more training as I see the real problem is lack of hand flying skills and confidence in flying without the nannies.

I think there is a really simple test to prove your assertion wrong. All other things being equal, had they been flying NG instead MAX, this thread wouldn't exist and there wouldn't be two craters in the ground.


Indeed. I think there's (for some reason) an attempt to confuse the issue by turning to attention from, say, airplane engineering skills to solely pilot skills (both could be questioned here) and by repeating ad nauseum. And making everything very simple. If only you flip a switch... NOT realising that the pilots in these situations are very close to ground in the most vulnerable moment of the flight, their speed instruments are malfunctioning (or at least some of them), stick shaker is going off, a potential bird hit has been made, the trim system is moving erratically but in a manner that isn't easy to observe. And perhaps, the manual backup isn't so easy to use.

In the end, I think some very bad design decisions were made which significantly contributed to the accident (but of course not only those). Boeing can and will fix this, but they also will end up paying for the loss of confidence and quite possibly in the lawsuits. May it be so. What I'm worried about is that neither Boeing nor the aviation community (at least as seen by some on a.net) seems to take the full lesson or see their errors. If the full lesson isn't learned, the fear is that this accident will repeat.

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