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DocLightning
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 3:45 am

sgrow787 wrote:
flyingphil wrote:
With the slowdown in air travel for the foreseeable future (6 months +), this will hardly make an impact. Also gives cover to continue working the MCAS issue. Coronavirus might have been the best thing that ever happened for Boeing in this crisis. I don't see Airbus orders going up if air travel is down across the board. Then there's shutdown of aircraft manufacturing plants due to quarantine.


Airlines place orders with turn-around times of 1-2 years out for the first deliveries. I predict a similar timescale for a coronavirus vaccine or other definitive solution. While this situation is a temporary reprieve for Boeing, airlines will still need to place orders with the future in mind. The latest development raises again a question once dismissed as hysterical and ridiculous: "Is the -MAX ever going to fly again?"

So if I'm a CEO with the -MAX on order, at least I don't have to worry much about lost capacity right now. But if I'm a CEO contemplating an order, I am going to have serious doubts about Boeing's ability to deliver it by the time I need it (if ever).
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enzo011
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:33 am

sgrow787 wrote:
With the slowdown in air travel for the foreseeable future (6 months +), this will hardly make an impact. Also gives cover to continue working the MCAS issue. Coronavirus might have been the best thing that ever happened for Boeing in this crisis. I don't see Airbus orders going up if air travel is down across the board. Then there's shutdown of aircraft manufacturing plants due to quarantine.



Glass half full, glass half empty to follow. With the slowdown in aviation and inevitable collapse of airlines and orders, slots will open at Airbus to sell the A320 to MAX customers in the short term and at the required demand.
 
FluidFlow
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:36 am

I thin Boeing just jumped on the oil price news. Running old frames just became really cheap.
 
sgrow787
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:48 am

enzo011 wrote:
sgrow787 wrote:
With the slowdown in air travel for the foreseeable future (6 months +), this will hardly make an impact. Also gives cover to continue working the MCAS issue. Coronavirus might have been the best thing that ever happened for Boeing in this crisis. I don't see Airbus orders going up if air travel is down across the board. Then there's shutdown of aircraft manufacturing plants due to quarantine.



Glass half full, glass half empty to follow. With the slowdown in aviation and inevitable collapse of airlines and orders, slots will open at Airbus to sell the A320 to MAX customers in the short term and at the required demand.


But I thought we already established that Airbus can't increase production over night.
Just one sensor,
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enzo011
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:54 am

sgrow787 wrote:
But I thought we already established that Airbus can't increase production over night.



If the crises continues there wouldn't need to be a need to increase production though. Keep it at the same level and new slots could open up as Airbus customers has to defer or cancel orders. This frees up slots to sell to MAX customers. As I said, my view is a pessimistic view for the MAX to the slowdown of the industry.
 
oschkosch
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 6:45 am

WSJ wiring report without a paywall is here. Sound spretty bad to me, 800 planes will need rework...

https://www.marketscreener.com/BOEING-C ... -30127963/

U.S. air-safety regulators are poised to order electrical wires relocated inside Boeing Co. 737 MAX jets in the latest complication and potential delay for their return to commercial service, according to people briefed on the deliberations. The preliminary decision, which hasn't been reported before, covers all of the nearly 800 MAX airliners produced so far. The decision could be affected by further internal discussions and additional data the plane maker may submit to the regulator. But in the past few weeks, these people said, Federal Aviation Administration managers and engineers have concluded that the potentially hazardous layout violates wiring-safety standards intended to prevent dangerous short-circuits.

If Boeing continues to press its case in the face of the FAA's preliminary decision, one of the people briefed on the deliberations said, the likely upshot would be months of additional debate involving the FAA and foreign regulators in Europe, Canada and Brazil. That is a major reason Boeing, which already has been devising ways to relocate certain wiring, ultimately is likely to accept the FAA's position. And from a public perception standpoint, the people said, U.S. authorities are loath to break with demands from foreign regulators that wiring fixes must be completed before the fleet is allowed to resume operations.

Canadian regulators haven't taken an official position yet on how Boeing should mitigate any risks associated with the wire bundles, said Nicholas Robinson, Transport Canada's director general of civil aviation. But privately, according to people familiar with the details, Canada strongly supports relocating some wires.
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BoeingVista
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 9:38 am

blrsea wrote:
If the same wiring issue exists in NG , then should it really be a blocker for Max's RTS? Somehow, that doesn't seem right to me. It could be fixed with an AD, giving it 6-12 months to retrofit all Maxs.


Its not the same issue, part of the wiring problem is bigger MAX engines = larger fan blades = more energy from an unconstrained failure = more fuselage penetration of debris, this now puts redundant pairs of wiring bundles into the firing line which is against the regulations. Boeing is aware that it had to relocate the bundles from a previous accident report of an uncontained failure on a NG before MAX was built. FAA should have caught it during certification but its caught now. The type certificate has been pulled and the FAA can't really return it to a non compliant aircraft while the rest of the worlds regulators are watching on even if they wanted to.
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XRAYretired
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 11:31 am

BoeingVista wrote:
blrsea wrote:
If the same wiring issue exists in NG , then should it really be a blocker for Max's RTS? Somehow, that doesn't seem right to me. It could be fixed with an AD, giving it 6-12 months to retrofit all Maxs.


Its not the same issue, part of the wiring problem is bigger MAX engines = larger fan blades = more energy from an unconstrained failure = more fuselage penetration of debris, this now puts redundant pairs of wiring bundles into the firing line which is against the regulations. Boeing is aware that it had to relocate the bundles from a previous accident report of an uncontained failure on a NG before MAX was built. FAA should have caught it during certification but its caught now. The type certificate has been pulled and the FAA can't really return it to a non compliant aircraft while the rest of the worlds regulators are watching on even if they wanted to.

This is a conflation of two different conditions.

Firstly the routing of the rudder control cables (not electrical wiring) susceptibility to being severed by debris from an uncontained engine failure. An 'AMOC' was submitted for MAX that was rejected by FAA experts (reportedly 12 to nil) and was at least partially based on the performance of the CFM on the NG, of course, a different engine altogether. But, the decision by FAA seniors was to accept, it would seem, at the behest of Boeing. Since no information is available to the contrary, I would assume this AMOC stands.

Secondly, the proximity of wiring bundles (electrical) routed to the tail and including the Stabilizer power and control wiring that is not in compliance with regulations that came into force post NG but prior to MAX certification that was not disclosed and includes a possibility of hot short resulting in stabilizer runaway. It is not yet clear if a hot short could result in a runaway or the reason(s) why FAA may be minded to reject the Boeing submission for retrospective waiver. It could be either or both the hot short potential (if it exists) or the mere fact MAX was non-compliant at certification.

In the second case, if rework is required, it will apply to all MAX frames and it would make no sense to put aircraft back in service prior to completion of the mod - they are sitting there with nothing else to do but wait for modification and pre-RTS maintenance anyway. The condition does apply to NG but it is compliant with the regulations at the time of certification (we assume), so any action required on NG will largely be based on the perceived probability of hot short causing stabilizer runaway that is now recognised as a potentially catastrophic failure mode but it was not so deemed at the time of NG certification.

Ray
 
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Francoflier
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 11:59 am

XRAYretired wrote:
In the second case, if rework is required, it will apply to all MAX frames and it would make no sense to put aircraft back in service prior to completion of the mod - they are sitting there with nothing else to do but wait for modification and pre-RTS maintenance anyway. The condition does apply to NG but it is compliant with the regulations at the time of certification (we assume), so any action required on NG will largely be based on the perceived probability of hot short causing stabilizer runaway that is now recognised as a potentially catastrophic failure mode but it was not so deemed at the time of NG certification.

Ray


They could start working on them once the modification is approved and before RTS, but think it would take too long to rework all the frames before RTS unless it's still years away.

I think Boeing and the FAA could probably agree on an AD to allow operators to start using their airplanes and have it done a bit later.
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
 
XRAYretired
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 12:13 pm

Francoflier wrote:
XRAYretired wrote:
In the second case, if rework is required, it will apply to all MAX frames and it would make no sense to put aircraft back in service prior to completion of the mod - they are sitting there with nothing else to do but wait for modification and pre-RTS maintenance anyway. The condition does apply to NG but it is compliant with the regulations at the time of certification (we assume), so any action required on NG will largely be based on the perceived probability of hot short causing stabilizer runaway that is now recognised as a potentially catastrophic failure mode but it was not so deemed at the time of NG certification.

Ray


They could start working on them once the modification is approved and before RTS, but think it would take too long to rework all the frames before RTS unless it's still years away.

I think Boeing and the FAA could probably agree on an AD to allow operators to start using their airplanes and have it done a bit later.

Boeing estimate was two weeks work. Boeing statement yesterday said it would not change the mid-summer estimate for RTS.

Ray
 
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keesje
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 12:59 pm

All said and done, looking forward, I guess / think there will be some kind of deal launching a new, "10% better than NEO+" for first flight in 2026. Included in the deal: US government (no laissez fair no more, on behalve of US taxpayers), Boeing, Spirit, Raytheon Collins, GE, NASA, FAA.

Free market ideology will temporary be parked, government support in many ways will flow, WTO be ignored. For the higher strategic interest of offering a US product in the biggest market segment. Smoke screens all over & Airbus will no doubt cry foul. In the end it's probably the best for the industry longer term.. Free market capitalism nearly killed Boeing, so the rule set changed.

A new "10% better than NEO+" would be available from 2026 earliest. Assume half the 4000 MAX aircraft will get cancelled or converted into the new aircraft, that means average deliveries of ~30MAX/month until production of the new one really picks up.. Airlines can overhaul their NG's for another 8 years, not as planned, but Boeing will pay (part of) the bill, or they'll get special tax cuts, whatever is required for continuity.

:arrow: Yes MAX will likely return to service. Ambitions & forecast originating <2020 are in the shredder. Too much happened, became clear.

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Francoflier
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 1:34 pm

XRAYretired wrote:
Boeing estimate was two weeks work. Boeing statement yesterday said it would not change the mid-summer estimate for RTS.

Ray


2 weeks work per airplane? If yes, doing 800 airframes represents an enormous amount of man-hours and I strongly believe there would be no way it could be done by this summer, even if they started today and with the help of the respective airlines' engineering departments.

I have no idea what this wiring rework would entail, but I suspect it will take a while to complete on the entire existing fleet. That's without even mentioning whatever else needs to be modified.
Best they start soon in any case...
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randomdude83
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 1:47 pm

Francoflier wrote:
XRAYretired wrote:
Boeing estimate was two weeks work. Boeing statement yesterday said it would not change the mid-summer estimate for RTS.

Ray


2 weeks work per airplane? If yes, doing 800 airframes represents an enormous amount of man-hours and I strongly believe there would be no way it could be done by this summer, even if they started today and with the help of the respective airlines' engineering departments.

I have no idea what this wiring rework would entail, but I suspect it will take a while to complete on the entire existing fleet. That's without even mentioning whatever else needs to be modified.
Best they start soon in any case...


Well you got the entire 737 work force. that would do it in no time I think?
 
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scbriml
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 2:05 pm

Francoflier wrote:
XRAYretired wrote:
Boeing estimate was two weeks work. Boeing statement yesterday said it would not change the mid-summer estimate for RTS.

Ray


2 weeks work per airplane? If yes, doing 800 airframes represents an enormous amount of man-hours and I strongly believe there would be no way it could be done by this summer, even if they started today and with the help of the respective airlines' engineering departments.


I think the reason Boeing is saying "no change to RTS estimate" is that RTS doesn't represent a point in time where all 800 MAX are ready to fly again. Technically, as long as just one is ready, then Boeing meets its "mid summer" RTS deadline. :spin:

I don't think anyone expects lots of MAX to RTS on day one.

randomdude83 wrote:
Well you got the entire 737 work force. that would do it in no time I think?


But how many of "the entire 737 workforce" would be qualified to do this work? And don't forget, while the 400 undelivered MAX are 'close' to Boeing, the other 400 are dotted all over the World.


It seems to me we're getting to the point where the long pole in the tent is pilot training.
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beechnut
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 2:37 pm

The interim Ethiopian report is out. A defective AOA sensor apperently triggered the events.

https://www.cbc.ca/news/world/ethiopia- ... -1.5490763
 
oschkosch
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 3:46 pm

beechnut wrote:
The interim Ethiopian report is out. A defective AOA sensor apperently triggered the events.

https://www.cbc.ca/news/world/ethiopia- ... -1.5490763



Finally a clear statement regarding training!!

Boeing criticized for 'inadequate' training
The Ethiopian report did not mention any errors by the pilots, merely noting they were trained, fully certified and medically cleared to fly. It criticized Boeing for "inadequate" training for pilots flying the new model because simulations did not include scenarios where MCAS was erroneously activated.

"Training should also include simulator sessions to familiarize with normal and non-normal MCAS operation. The training simulators need to be capable of simulating AOA failure scenarios," it recommended.
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Revelation
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 3:55 pm

scbriml wrote:
I think the reason Boeing is saying "no change to RTS estimate" is that RTS doesn't represent a point in time where all 800 MAX are ready to fly again. Technically, as long as just one is ready, then Boeing meets its "mid summer" RTS deadline. :spin:

I don't think anyone expects lots of MAX to RTS on day one.

Indeed. Recovery is going to be a long drawn out affair, much like the T1000 and PW GTF repair cycles have been. It's not like a flag will drop and all 800 MAXes will take off that morning.

scbriml wrote:
It seems to me we're getting to the point where the long pole in the tent is pilot training.

I think the near term road block is the safety analysis. Now we see the ET tragedy is blamed on one bad AoA sensor. Well, it was the failed safety analysis (presumably rushed if not steered by financial concerns) that led Boeing to move ahead with the one sensor design. I'm sure the FAA is going through the entire stack of documentation to support the safety analysis and making sure it's as sound as it can be. We see FAA is not giving any wiggle room with regard to wiring bundles that have never failed in tens of millions of NG flight hours. I don't think they will be giving any wiggle room on the safety analysis.

FAA Chief Dickson recently said we're only a few audit items away from the certification flight, but it's always those last items that take the most effort to close out, in my experience. It's the old 80/20 rule: 20% of the tasks take 80% of the resources to resolve.
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:15 pm

Francoflier wrote:
XRAYretired wrote:
Boeing estimate was two weeks work. Boeing statement yesterday said it would not change the mid-summer estimate for RTS.

Ray


2 weeks work per airplane? If yes, doing 800 airframes represents an enormous amount of man-hours and I strongly believe there would be no way it could be done by this summer, even if they started today and with the help of the respective airlines' engineering departments.

Until the FAA approves the fix Boeing cannot commence anything, so once again, back to the FAA.....
Maybe the Boeing estimate of mid-summer is more realistic than the optimism of the head of the FAA.....wonder how the stock is performing, maybe it is lost in the airlines need to keep flying in spite of the virus?
 
Cruiser
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:16 pm

Revelation wrote:
It's not like a flag will drop and all 800 MAXes will take off that morning.


That would be a sight to see though...800 planes one after another!
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:18 pm

scbriml wrote:
It seems to me we're getting to the point where the long pole in the tent is pilot training.

Well we still have MCAS which so far no one seems to believe the June-2019 updates, so the long pole is still MCAS.

The other regulators will all have their own training methods that they will put in place, and this will be in addition to those put in place by the individual airlines, somehow I think folks are overlooking the individual airlines in this debate.
 
UpNAWAy
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:22 pm

How will the FAA justify not requiring a wire fix on the B737-NGs also?
 
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PixelFlight
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:24 pm

beechnut wrote:
The interim Ethiopian report is out. A defective AOA sensor apperently triggered the events.

https://www.cbc.ca/news/world/ethiopia- ... -1.5490763
:thumbsup: :checkmark:
Thanks for that link.

As expected there is a long part starting page 77 [PDF page 79] about the trim wheels. There tested a lot of aspects of it using there 737 MAX simulator. I found that this sentence summarize in bold the very issue of the 737 MAX (and probably the 737 NG):

"For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level
of turning the manual trim wheel was level A (trim wheel not movable)."


So the issue is far more related to the misstrim induced by the MCAS than related to the speed. The small overspeed over VMO (340 kts) was really not the problem !
How this can be certified to fly ?
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
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Revelation
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 5:34 pm

par13del wrote:
Well we still have MCAS which so far no one seems to believe the June-2019 updates, so the long pole is still MCAS.

The other regulators will all have their own training methods that they will put in place, and this will be in addition to those put in place by the individual airlines, somehow I think folks are overlooking the individual airlines in this debate.

I don't think we've heard much pushback on the MCAS fix itself. I think we have heard push back on the "cosmic ray" fix. The audit of last year turned up the display initiation issue. Dickson said there were still a few outstanding tasks from the software audit but these should allow for first flight in a few weeks so I don't think they are showstoppers.

The training is problematic since it's all so subjective and since so many different people all have to agree on the solution. I don't envy anyone working on the issue. It'll be very difficult to please everyone.
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JetBuddy
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 6:42 pm

PixelFlight wrote:
beechnut wrote:
The interim Ethiopian report is out. A defective AOA sensor apperently triggered the events.

https://www.cbc.ca/news/world/ethiopia- ... -1.5490763
:thumbsup: :checkmark:
Thanks for that link.

As expected there is a long part starting page 77 [PDF page 79] about the trim wheels. There tested a lot of aspects of it using there 737 MAX simulator. I found that this sentence summarize in bold the very issue of the 737 MAX (and probably the 737 NG):

"For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level
of turning the manual trim wheel was level A (trim wheel not movable)."


So the issue is far more related to the misstrim induced by the MCAS than related to the speed. The small overspeed over VMO (340 kts) was really not the problem !
How this can be certified to fly ?


I wonder the same thing. Speeds above 220 kts is more than 90% of a typical flight.
 
asdf
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 6:45 pm

JetBuddy wrote:
PixelFlight wrote:
beechnut wrote:
The interim Ethiopian report is out. A defective AOA sensor apperently triggered the events.

https://www.cbc.ca/news/world/ethiopia- ... -1.5490763
:thumbsup: :checkmark:
Thanks for that link.

As expected there is a long part starting page 77 [PDF page 79] about the trim wheels. There tested a lot of aspects of it using there 737 MAX simulator. I found that this sentence summarize in bold the very issue of the 737 MAX (and probably the 737 NG):

"For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level
of turning the manual trim wheel was level A (trim wheel not movable)."


So the issue is far more related to the misstrim induced by the MCAS than related to the speed. The small overspeed over VMO (340 kts) was really not the problem !
How this can be certified to fly ?


I wonder the same thing. Speeds above 220 kts is more than 90% of a typical flight.



on a aerodynamical clean and well constructed plane you nearly never need the manual trim wheel
so the problem never occurred since the jurassic, never mention on the NG
 
EAARbrat
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 8:14 pm

oschkosch wrote:
The Ethiopian report did not mention any errors by the pilots, merely noting they were trained, fully certified and medically cleared to fly.


Is ignoring throttle position a memory/training item in Ethiopia?

Don't misunderstand Boeing is flat out guilty.
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sgrow787
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 9:45 pm

In my opinion if the manual trim wheel is implicated in the Ethiopian crash, which involved the 737 Max, and which resulted in its grounding, then discussion of it should be allowed in this thread which is about the 737 Max. 

Not to mention the timely importance of the FAA hinting at a 737 Max RTS this summer without mentioning the trim wheel at all.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
beechnut
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 10:01 pm

The ET report points to a very serious problem with the MAX: when it goes out of trim nose-down, it's almost impossible to bring it back. Quite apart from the report, this is a serious issue that needs to be addressed by Boeing (who reduced the size of the trim wheels, and hence leverage, back with the NG). I agree that this needs to be discussed here as it will likely impact RTS. We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

It begs the question: how on earth could MCAS V1.0 ever have been certified, and why is V2.0 still pending. It sounds like Boeing did not do a proper analysis of the consequences of an MCAS-induced out-of-trim. And I'm starting to think that the analysis of V2.0 is revealing that it has its own "gotchas".

Clearly it was not a matter of *if* a MAX would crash, but *when* with MCAS V1.0. I am just flabbergasted that such a half-baked solution ever made it into a modern airliner.

I'll say it again: IMHO, the MAX will never RTS. When an insider I know at TC first told me that last year, I scoffed. But now I'm beginning to think he's right.

Beech
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 10:05 pm

blrsea wrote:
If the same wiring issue exists in NG , then should it really be a blocker for Max's RTS? Somehow, that doesn't seem right to me. It could be fixed with an AD, giving it 6-12 months to retrofit all Maxs.


Exactly. If the FAA is requiring a fix on the MAX, they must explain why it isn't an issue on the NG.

If the same potential issue exists on the NG then either they both need to be fixed or neither needs to be fixed.

If there is an AD for both, I can see why they would require the MAX AD to be implemented before RTS. It isn't really going to delay much, if at all, anyway so they might as well be able to say that everything deemed necessary has been fixed.
 
asdf
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 10:41 pm

EAARbrat wrote:
oschkosch wrote:
The Ethiopian report did not mention any errors by the pilots, merely noting they were trained, fully certified and medically cleared to fly.


Is ignoring throttle position a memory/training item in Ethiopia?.


if they have a unreliable airspeed indication memoryitems are basically power&climb, arent they?
their airspeed seems not had any influence on the outcome
 
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 10:53 pm

beechnut wrote:
We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

Which mechanism is that?
 
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767333ER
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 11:00 pm

beechnut wrote:
The ET report points to a very serious problem with the MAX: when it goes out of trim nose-down, it's almost impossible to bring it back. Quite apart from the report, this is a serious issue that needs to be addressed by Boeing (who reduced the size of the trim wheels, and hence leverage, back with the NG). I agree that this needs to be discussed here as it will likely impact RTS. We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

It begs the question: how on earth could MCAS V1.0 ever have been certified, and why is V2.0 still pending. It sounds like Boeing did not do a proper analysis of the consequences of an MCAS-induced out-of-trim. And I'm starting to think that the analysis of V2.0 is revealing that it has its own "gotchas".

Clearly it was not a matter of *if* a MAX would crash, but *when* with MCAS V1.0. I am just flabbergasted that such a half-baked solution ever made it into a modern airliner.

I'll say it again: IMHO, the MAX will never RTS. When an insider I know at TC first told me that last year, I scoffed. But now I'm beginning to think he's right.

Beech

So much for the “apparent lack of skill” of the third world country crew allowing it to go over Vmo causing the trim force to be insurmountable... it just is anyway.
Been on: 732 733 734 73G 738 752 763 A319 A320 A321 CRJ CR7 CRA/CR9 E145 E175 E190 F28 MD-82 MD-83 C172R C172S P2006T PA-28-180

2 ears for spatial hearing, 2 eyes for depth perception, 2 ears for balance... How did Boeing think 1 sensor was good enough?!
 
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keesje
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 11:14 pm

Aerodynamic corrections, a redesigned emergency warning system, full human interface review, powerfull, redundant trim system, helpfull FCS and a big sorry for the certification process. Powerplay and patches probably won't impress EASA and other authorities.
"Never mistake motion for action." Ernest Hemingway
 
beechnut
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 11:22 pm

par13del wrote:
beechnut wrote:
We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

Which mechanism is that?


MCAS!!!!
 
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Mon Mar 09, 2020 11:42 pm

beechnut wrote:
par13del wrote:
beechnut wrote:
We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

Which mechanism is that?


MCAS!!!!

So you think the MAX is going to RTS with MCAS unchanged? Boeing submitted a fix to MCAS in June-2019, I guess that was lost in the bit flip, wire bundle, nacelle gap, Jedi Mind tricks, e-mail, removal of the head of Boeing that persons still believe that the MAX is still grounded because MCAS cannot be fixed or updated.
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 12:18 am

beechnut wrote:
The ET report points to a very serious problem with the MAX: when it goes out of trim nose-down, it's almost impossible to bring it back. Quite apart from the report, this is a serious issue that needs to be addressed by Boeing (who reduced the size of the trim wheels, and hence leverage, back with the NG). I agree that this needs to be discussed here as it will likely impact RTS. We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

It begs the question: how on earth could MCAS V1.0 ever have been certified, and why is V2.0 still pending. It sounds like Boeing did not do a proper analysis of the consequences of an MCAS-induced out-of-trim. And I'm starting to think that the analysis of V2.0 is revealing that it has its own "gotchas".

Clearly it was not a matter of *if* a MAX would crash, but *when* with MCAS V1.0. I am just flabbergasted that such a half-baked solution ever made it into a modern airliner.

I'll say it again: IMHO, the MAX will never RTS. When an insider I know at TC first told me that last year, I scoffed. But now I'm beginning to think he's right.

Beech


First, I think it should be clarified that when out of trim it is almost impossible to bring back using the manual wheel. It is possible with the electric trim switches. I was very disappointed that the interim report did not address an explanation as to why they moved the cutout switches while the captain was trimming nose up. Nor does it discuss why they barely held the switches at all after turning electric trim back on. I was hoping that they would address that to validate (or invalidate) what I just stated about being possible with manual electric trim.

As for the wheel. I'm not so sure it was any more effective from a practical standpoint on the Jurassic or the Classic. Nobody has posted what the diameter used to be or what it is now. To do an exact calculation of the mechanical gain would require those diameters. However, I have trouble conceptualizing that a slightly larger wheel would get from "impossible to move" to "works just fine." The fact that the "roller coaster procedure" was created on the Jurassic would indicate that the larger wheel wasn't much better.

It seems to me that the design of the wheel from the beginning was to be the backup in the event the actuators failed and that the normal use would start with an in-trim or close to in-trim state.
 
mjoelnir
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 12:27 am

planecane wrote:
beechnut wrote:
The ET report points to a very serious problem with the MAX: when it goes out of trim nose-down, it's almost impossible to bring it back. Quite apart from the report, this is a serious issue that needs to be addressed by Boeing (who reduced the size of the trim wheels, and hence leverage, back with the NG). I agree that this needs to be discussed here as it will likely impact RTS. We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

It begs the question: how on earth could MCAS V1.0 ever have been certified, and why is V2.0 still pending. It sounds like Boeing did not do a proper analysis of the consequences of an MCAS-induced out-of-trim. And I'm starting to think that the analysis of V2.0 is revealing that it has its own "gotchas".

Clearly it was not a matter of *if* a MAX would crash, but *when* with MCAS V1.0. I am just flabbergasted that such a half-baked solution ever made it into a modern airliner.

I'll say it again: IMHO, the MAX will never RTS. When an insider I know at TC first told me that last year, I scoffed. But now I'm beginning to think he's right.

Beech


First, I think it should be clarified that when out of trim it is almost impossible to bring back using the manual wheel. It is possible with the electric trim switches. I was very disappointed that the interim report did not address an explanation as to why they moved the cutout switches while the captain was trimming nose up. Nor does it discuss why they barely held the switches at all after turning electric trim back on. I was hoping that they would address that to validate (or invalidate) what I just stated about being possible with manual electric trim.

As for the wheel. I'm not so sure it was any more effective from a practical standpoint on the Jurassic or the Classic. Nobody has posted what the diameter used to be or what it is now. To do an exact calculation of the mechanical gain would require those diameters. However, I have trouble conceptualizing that a slightly larger wheel would get from "impossible to move" to "works just fine." The fact that the "roller coaster procedure" was created on the Jurassic would indicate that the larger wheel wasn't much better.

It seems to me that the design of the wheel from the beginning was to be the backup in the event the actuators failed and that the normal use would start with an in-trim or close to in-trim state.


It was know to not work fine on all frames it was installed. There is a reason for the not any longer trained roller coaster method. That method does not do well near the ground. But both decreasing the diameter and increasing the surface it was working on, made a bad situation worse.
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 12:45 am

mjoelnir wrote:
planecane wrote:
beechnut wrote:
The ET report points to a very serious problem with the MAX: when it goes out of trim nose-down, it's almost impossible to bring it back. Quite apart from the report, this is a serious issue that needs to be addressed by Boeing (who reduced the size of the trim wheels, and hence leverage, back with the NG). I agree that this needs to be discussed here as it will likely impact RTS. We have a mechanism that puts the plane out-of-trim based on a single erroneous sensor input, and no means of bringing it back into trim when the airspeed goes above 220 kts!!!

It begs the question: how on earth could MCAS V1.0 ever have been certified, and why is V2.0 still pending. It sounds like Boeing did not do a proper analysis of the consequences of an MCAS-induced out-of-trim. And I'm starting to think that the analysis of V2.0 is revealing that it has its own "gotchas".

Clearly it was not a matter of *if* a MAX would crash, but *when* with MCAS V1.0. I am just flabbergasted that such a half-baked solution ever made it into a modern airliner.

I'll say it again: IMHO, the MAX will never RTS. When an insider I know at TC first told me that last year, I scoffed. But now I'm beginning to think he's right.

Beech


First, I think it should be clarified that when out of trim it is almost impossible to bring back using the manual wheel. It is possible with the electric trim switches. I was very disappointed that the interim report did not address an explanation as to why they moved the cutout switches while the captain was trimming nose up. Nor does it discuss why they barely held the switches at all after turning electric trim back on. I was hoping that they would address that to validate (or invalidate) what I just stated about being possible with manual electric trim.

As for the wheel. I'm not so sure it was any more effective from a practical standpoint on the Jurassic or the Classic. Nobody has posted what the diameter used to be or what it is now. To do an exact calculation of the mechanical gain would require those diameters. However, I have trouble conceptualizing that a slightly larger wheel would get from "impossible to move" to "works just fine." The fact that the "roller coaster procedure" was created on the Jurassic would indicate that the larger wheel wasn't much better.

It seems to me that the design of the wheel from the beginning was to be the backup in the event the actuators failed and that the normal use would start with an in-trim or close to in-trim state.


It was know to not work fine on all frames it was installed. There is a reason for the not any longer trained roller coaster method. That method does not do well near the ground. But both decreasing the diameter and increasing the surface it was working on, made a bad situation worse.


My point being that nothing in my logical, engineering brain, indicates that even if you went back to the original trim wheel on the NG and MAX that it would move under the same conditions that the current wheel doesn't move. It seems clear to me that if we could go back in time to listen to the design discussions in 1965 we'd find that the wheel was a backup to an actuator failure and neve meant to work if the aircraft was out of trim significantly.
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 3:59 am

blrsea wrote:




The electric trim reactivates the MCAS 1.0 system. The instructions given after the Lion air crash never mentioned about the unworkability of the manual trim system under load or other ways to alleviate the trim down. If I remember right, someone mentioned a procedure from 737 classic where you activate electrical trm and then then deactivate it and do it multiple times where you go up and down till it stabilizes or reaches safe altitude for troubleshooting. It seems that procedure was removed from NG.


What you are thinking of is the "roller coaster procedure" that was in a training manual for the 737-200. It is still in the training documentation that I found for the NG but it isn't as detailed and referred to as load alleviation.

The procedure is to eliminate the force needed to turn the manual trim wheel when there is a lot of elevator deflection. Essentially, when you pull back on the column and lift the elevators, the force also pushes the jack screw nut up against the jack screw threads through the stabilizer. This creates a lot of friction which makes it difficult, if not impossible, to turn the manual trim wheel under certain conditions.

The procedure is basically to stop pulling back on the control column for a few seconds so that the elevator is "flat" with the stabilizer and then turn the wheel a few turns and then pull back again to regain the desired pitch. The process is repeated until the aircraft is in trim or close enough that the wheel can be turned.
 
Ishrion
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 6:37 am

Exactly one year ago, ET302 crashed after takeoff.
 
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PixelFlight
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 8:16 am

planecane wrote:
My point being that nothing in my logical, engineering brain, indicates that even if you went back to the original trim wheel on the NG and MAX that it would move under the same conditions that the current wheel doesn't move. It seems clear to me that if we could go back in time to listen to the design discussions in 1965 we'd find that the wheel was a backup to an actuator failure and neve meant to work if the aircraft was out of trim significantly.

Not even sure about that...
But what is certain it that this at least violate the regulation back in 2012 at the time of the 737 MAX "Amended Type Certification (Atc)Application".
Because the "out-of-trim" regulation was pretty strict already. See the ET302 report chapter "1.17.6 AIRWORTHINESS REGULATIONS AIRWORTHINESS STANDARD FOR TYPE CERTIFICATE".
This was a know weak point in the early 737 models already, so it should have been progressively improved in a half of century and a dozen of derivatives. But instead Boeing not only did not improved this. but added more automation to the stab trim, removed the second motor for manual electric trim, and removed 2.5 degree out-of-trim training at speed above 220 kts. This paved the way of the idea of going more in that false direction, up to the unbelievably unsafe MCAS.

From my eyes, the 737 MAX still violate the out-of-trim regulation and I don't see any progress on that subject, neither from Boeing, nor from the FAA, nor from EASA. I found this scary.
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
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MillwallSean
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 8:49 am

Sadly today is a year since the horrible events tat happened.

With this even now being a year ago, it is interesting, to return to the early posts about the 737 Max and its return to service.
One can see a clear link between posters that are absolute in statements and conclusions and their inability to predict return to service. This makes it quite easy to question credibility and such posters ability to understand complex events and based on those draw relevant conclusions.

Personally I thought the Max would fly within 6 months. But I sure didn't proclaim to have the truth and ability to provide absolute truths.
No One Likes Us - We Dont Care.
 
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PixelFlight
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 8:50 am

planecane wrote:
First, I think it should be clarified that when out of trim it is almost impossible to bring back using the manual wheel. It is possible with the electric trim switches. I was very disappointed that the interim report did not address an explanation as to why they moved the cutout switches while the captain was trimming nose up. Nor does it discuss why they barely held the switches at all after turning electric trim back on. I was hoping that they would address that to validate (or invalidate) what I just stated about being possible with manual electric trim.

As for the wheel. I'm not so sure it was any more effective from a practical standpoint on the Jurassic or the Classic. Nobody has posted what the diameter used to be or what it is now. To do an exact calculation of the mechanical gain would require those diameters. However, I have trouble conceptualizing that a slightly larger wheel would get from "impossible to move" to "works just fine." The fact that the "roller coaster procedure" was created on the Jurassic would indicate that the larger wheel wasn't much better.

It seems to me that the design of the wheel from the beginning was to be the backup in the event the actuators failed and that the normal use would start with an in-trim or close to in-trim state.

About your first part, I share the concern about understanding why all the existing FDR data on the MCAS induced out-of-trim, from JT043, JT610, and ET302, shows consistently that all the pilots stopped too early the manual electric trim correction just before using the STAB TRIM CUTOUT. I think that the badly redacted procedure play a big role here. In that procedure, the worst and imminently fatal situation is documented at his end in a small notice. The procedure should have been designed to survive the worst and urgent case first in bold. The training must also be more specific on that point. Finally I also suspect that the pilots, for some reasons, did not feel correctly when the stab trim neutralize the elevator pitch. I speculate that this could be when both pilots activate the yoke pitch: the pilot using the electric stab trim stop when he feel the pitch force neutralized on his yoke, without taking account of the pitch force on the other yoke. Regardless of the reason, this neutralization issue should deserve a better analysis in my opinion.

Note: All of this should have been different if the 737 MAX still allowed to cutout the FCC stab trim without cutting the manual electrical trim, as in early 737 models.

As for the wheels force calculation, the ET302 report contain a figure 66 "FORCE NEEDED TO MOVE THE TRIM WHEEL" resulting from "The airplane manufacturer computed the force to apply on the trim wheel handle to move the stabilizer.". See ET302 report page 93 and 94 (PDF page 95 and 06).
:stirthepot: 737-8 MAX: "For all speeds higher than 220 Kts and trim set at a value of 2.5 units, the difficulity level of turning the manual trim wheel was level A (trim wheel not movable)." :stirthepot:
 
rheinwaldner
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 10:37 am

asdf wrote:
SQ22 wrote:
Please discuss the ET302 report in a separate thread and keep this thread on topic. Thanks.


well, it obviously was not a problem for the moderation that some users since months mixed a discussion about pilots training into this thread at every stage possible.
one user has managed to use the term "pilot training" nearly 600 times in the last year in this MAX threads.

the ET crash is magnitudes more a part of the grounding discussion then pilots training ....
as the ET report now proves very impressive


Agreed.

In the Lionair report, on less than 3% of the pages pilot failures were mentioned. But these 3% of the Lionair report were discussed in this thread for dozens of pages as if the grounding would not exist.

So why exactly is the ET report not on topic while 3% of the Lionair report dominated the same thread?
Many things are difficult, all things are possible!
 
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 11:43 am

rheinwaldner wrote:
asdf wrote:
SQ22 wrote:
Please discuss the ET302 report in a separate thread and keep this thread on topic. Thanks.


well, it obviously was not a problem for the moderation that some users since months mixed a discussion about pilots training into this thread at every stage possible.
one user has managed to use the term "pilot training" nearly 600 times in the last year in this MAX threads.

the ET crash is magnitudes more a part of the grounding discussion then pilots training ....
as the ET report now proves very impressive


Agreed.

In the Lionair report, on less than 3% of the pages pilot failures were mentioned. But these 3% of the Lionair report were discussed in this thread for dozens of pages as if the grounding would not exist.

So why exactly is the ET report not on topic while 3% of the Lionair report dominated the same thread?

Perhaps the protectors of the pilots have take some time off, so every post about pilots and training is no longer immediately followed up with a post about Boeing's failures.
I must admit, that give and take was getting old, and like it or not, some interesting discussions have taken place on the entire cockpit environment.
 
XRAYretired
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 11:57 am

The credible voice of reason. Engineering sciece if you like.
'...a common misunderstanding is that ET302 excessive speed made trimming harder.
Just the opposite!
The mistrim was excessive nose down trim.
The trim point is faster, it will lessen the opposing elevator force.
I don’t believe the crew were thinking this, instead workload overload....'

https://twitter.com/Satcom_Guru/status/ ... 2556026880

Pilots were overwhelmed.

So much for the a.nutters who fought tooth and nail to insist the manual trim wheel was not attempted or the extendable handle was not used despite the clear deduction from the preliminary report. The interim report makes it absolutely clear that manual trim was attempted, including the use of the extendable handle, and was unsuccessful. The subsequent tests and analysis by Boeing confirm this would have been so.

It is clear that it was the intention of the experienced PIC -
('....PIC has flown as first officer on different Aircraft, like B737 from 22 April, 2011 to 06 February 2013 for 2600hrs, 767 from February 2013, to October, 2014 and B777 and 787 for 2145hrs for consecutive time. From 26 October, 2017 until the end of the event he was a captain on B737 and flown for 1417 hrs as PIC on type.....'
avherald.com/files/ethiopian_b38m_et-avj_190310_preliminary_report_20200309.pdf)

- was to climb to 14000ft ASL (~7000ft AGL) and stablise in order to trouble shoot. This is consistent with the crews of three other single side stick shaker/IAS Unreliable events where thrust was maintained or increased and climb maintained. In two of the three events, A/P engage was at least attempted as well.

MCAS and other extraneous effects of incorrect but undetected AoA on other systems also contrived to restrict climb rate as well as contribute to overwhelming the pilots.

Ray
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 12:22 pm

XRAYretired wrote:
The credible voice of reason. Engineering sciece if you like.
'...a common misunderstanding is that ET302 excessive speed made trimming harder.
Just the opposite!
The mistrim was excessive nose down trim.
The trim point is faster, it will lessen the opposing elevator force.
I don’t believe the crew were thinking this, instead workload overload....'

https://twitter.com/Satcom_Guru/status/ ... 2556026880

Pilots were overwhelmed.

So much for the a.nutters who fought tooth and nail to insist the manual trim wheel was not attempted or the extendable handle was not used despite the clear deduction from the preliminary report. The interim report makes it absolutely clear that manual trim was attempted, including the use of the extendable handle, and was unsuccessful. The subsequent tests and analysis by Boeing confirm this would have been so.

It is clear that it was the intention of the experienced PIC -
('....PIC has flown as first officer on different Aircraft, like B737 from 22 April, 2011 to 06 February 2013 for 2600hrs, 767 from February 2013, to October, 2014 and B777 and 787 for 2145hrs for consecutive time. From 26 October, 2017 until the end of the event he was a captain on B737 and flown for 1417 hrs as PIC on type.....'
avherald.com/files/ethiopian_b38m_et-avj_190310_preliminary_report_20200309.pdf)

- was to climb to 14000ft ASL (~7000ft AGL) and stablise in order to trouble shoot. This is consistent with the crews of three other single side stick shaker/IAS Unreliable events where thrust was maintained or increased and climb maintained. In two of the three events, A/P engage was at least attempted as well.

MCAS and other extraneous effects of incorrect but undetected AoA on other systems also contrived to restrict climb rate as well as contribute to overwhelming the pilots.

Ray


His statement doesn't make any sense to me. Why would more speed which leads to more force per degree of elevator deflection make it easier to turn the wheel while applying maximum elevator deflection possible?
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 12:56 pm

rheinwaldner wrote:
asdf wrote:
SQ22 wrote:
Please discuss the ET302 report in a separate thread and keep this thread on topic. Thanks.


well, it obviously was not a problem for the moderation that some users since months mixed a discussion about pilots training into this thread at every stage possible.
one user has managed to use the term "pilot training" nearly 600 times in the last year in this MAX threads.

the ET crash is magnitudes more a part of the grounding discussion then pilots training ....
as the ET report now proves very impressive


Agreed.

In the Lionair report, on less than 3% of the pages pilot failures were mentioned. But these 3% of the Lionair report were discussed in this thread for dozens of pages as if the grounding would not exist.

So why exactly is the ET report not on topic while 3% of the Lionair report dominated the same thread?


Something conspicuously missing from the CVR excerpts in the ET interim report is ANY mention of ANY checklist or even discussion of the problem. Forget about the runaway stabilizer NNC that the AD specified but no checklist for any problem.

The discussion/action to cutout the stab trim switches just came out of thin air. It wasn't part of running a checklist.

Either these discussions were left out to hide something contained in them or they didn't take place. I'm going to assume the latter.

If this is the case it shows some level of pilot error for not following any training or CRM.
 
Flying-Tiger
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 1:19 pm

Something conspicuously missing from the CVR excerpts in the ET interim report is ANY mention of ANY checklist or even discussion of the problem. Forget about the runaway stabilizer NNC that the AD specified but no checklist for any problem.

The discussion/action to cutout the stab trim switches just came out of thin air. It wasn't part of running a checklist.

Either these discussions were left out to hide something contained in them or they didn't take place. I'm going to assume the latter.

If this is the case it shows some level of pilot error for not following any training or CRM.


Or, quite simple, no time to dig into the manuals, just trying to keep the bird in the air. If you´re only a couple of 100 ft above the ground over rugged train and travelling at 300ü mph it´s probably more important to gain altitute to get to a position to work through the problem and to rectify it. Ever tried to read a manual when traveling 100 mph on a motorway? No good idea... Aviate, navigage, communicate.
Flown: A319/320/321,A332/3,A343/346, A359, A380,AT4,AT7,B712, B732/3/4/5/7/8/9,B742/4,B752/3, B762/763,B772/77W,CR2/7/9/K,ER3/4,E70/75/90/95, F50/70/100,M11,L15,SF3,S20, AR8/1, 142/143,... 330.860 miles and counting.
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, March 2020

Tue Mar 10, 2020 1:48 pm

Flying-Tiger wrote:
Something conspicuously missing from the CVR excerpts in the ET interim report is ANY mention of ANY checklist or even discussion of the problem. Forget about the runaway stabilizer NNC that the AD specified but no checklist for any problem.

The discussion/action to cutout the stab trim switches just came out of thin air. It wasn't part of running a checklist.

Either these discussions were left out to hide something contained in them or they didn't take place. I'm going to assume the latter.

If this is the case it shows some level of pilot error for not following any training or CRM.


Or, quite simple, no time to dig into the manuals, just trying to keep the bird in the air. If you´re only a couple of 100 ft above the ground over rugged train and travelling at 300ü mph it´s probably more important to gain altitute to get to a position to work through the problem and to rectify it. Ever tried to read a manual when traveling 100 mph on a motorway? No good idea... Aviate, navigage, communicate.


Except they communicated with ATC which is supposed to be last on the list. They didn't discuss memory items. They didn't mention the EAD. They didn't discuss much of what was going on. They stayed airborne for several minutes. If it was a quick loss of control situation then I would understand just doing whatever was instinctive.
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Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos