B737MAX [Grounded as of 13 March 2019]

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Old May 20, 19, 1:23 am   -   Wikipost
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United does not fly the 737MAX8 that has been involved in two recent crashes, but it does operate the 737MAX9.

How to tell if your flight is scheduled to be operated by the MAX 9:

View your reservation or flight status page, either on the web or on the app. United lists the entire aircraft type. Every flight that is scheduled to be on the 737 MAX will say "Boeing 737 MAX 9." If you see anything else -- for example, "Boeing 737-900," it is not scheduled to be a MAX at this time.

The same is true in search results and anywhere else on the United site.

For advanced users: UA uses the three letter IATA identifier 7M9.

All 737MAX aircraft are currently grounded, with exceptions for non-passenger-carrying positioning flights (e.g., to move them to a storage area until the grounding is lifted).
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Old May 15, 19, 10:43 am
  #1411  
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Originally Posted by spin88 View Post
People keep making this argument, and its just wrong. In both the lion air and Ethiopian crashes the pilots fixed the trim, only to have it go back out rapidly on its own. This was not a one time problem, it was a problem that kept re-occurring when the run-away trim process was used. And the usual thought, turn off the auto pilot did not fix the problem.
In both crashes they failed to follow the five decade old runaway stab trim procedure which includes flipping the stab cutout switches and leaving them there. In the Ethiopian case, they were also likely too slow to react to the problem, which compounded their difficulties with manual trim.
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Old May 15, 19, 10:57 am
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Originally Posted by worldclubber View Post
"near-impossible" is bad enough, you are right.
It might be helpful to consider how they got into the situation that made it so difficult to operate the trim with the manual trim-wheels.
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Old May 15, 19, 11:39 am
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Originally Posted by LarryJ View Post
It might be helpful to consider how they got into the situation that made it so difficult to operate the trim with the manual trim-wheels.
I know exactly where youíre going with that and totally agree with you Larry, but pick your battles.

Very few here have the willingness to put aside their media driven interpretation of the events and be receptive to accept feedback from experienced pilots with knowledge of this aircraft.
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Old May 15, 19, 12:30 pm
  #1414  
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Originally Posted by LarryJ View Post
It might be helpful to consider how they got into the situation that made it so difficult to operate the trim with the manual trim-wheels.
How about next time you're in a 737 sim that also has mcas and see if you're able to recover the plane as per the Ethiopian airlines situation and report back.
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Old May 15, 19, 12:34 pm
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Originally Posted by LarryJ View Post
It might be helpful to consider how they got into the situation that made it so difficult to operate the trim with the manual trim-wheels.
Sure.

But the question remains; Why do the allegedly badly trained "third-world" pilots have a problem with these runaways on the max but not on the ng? mcas could be the difference, or something else.
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Old May 15, 19, 12:49 pm
  #1416  
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Originally Posted by clubord View Post

I know exactly where youíre going with that and totally agree with you Larry, but pick your battles.
Very few here have the willingness to put aside their media driven interpretation of the events and be receptive to accept feedback from experienced pilots with knowledge of this aircraft.
Originally Posted by USA_flyer View Post
How about next time you're in a 737 sim that also has mcas and see if you're able to recover the plane as per the Ethiopian airlines situation and report back.
OK then
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Old May 15, 19, 12:59 pm
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Originally Posted by USA_flyer View Post
How about next time you're in a 737 sim that also has mcas and see if you're able to recover the plane as per the Ethiopian airlines situation and report back.
You bet this will be covered in future B737 recurrent training curriculums along with a demonstration on non-recovery compliance with MCAS, probably in both high and low speed regimes.

Unfortunately it seems like the ET pilots got themselves in a tough position with the multiple MCAS trim inputs without disconnecting electric trim and/or providing proper runaway trim recovery techniques.

The situation compounded due to an extreme high speed/thrust setting. Either A) Auto-throttles were never disconnected (per procedure) or B) Airplane captured altitude hold setting keeping the current airspeed/thrust position and pilots never reduced to a manageable speed.

At a slower airspeed, manual trim movements are easier to conduct and the negative aerodynamic effects of the out of trim situation are significantly reduced. Flying fast with takeoff or climb thrust still active and trying to handle a flight control issue, thatís a really difficult position to recover from.
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Old May 15, 19, 1:12 pm
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Originally Posted by clubord View Post
The situation compounded due to an extreme high speed/thrust setting. Either A) Auto-throttles were never disconnected (per procedure) or B) Airplane captured altitude hold setting keeping the current airspeed/thrust position and pilots never reduced to a manageable speed.
The data that I've seen indicates that they (ET302) were in LVL CHG with a higher altitude selected on the MCP. That puts the autothrottles into N1 mode with an N1 setting of CLB (climb power). A/T was never disconnected. Thrust stayed at 91% N1 until a few seconds before the end of the flight. Indicated airspeed was as high as 390 KIAS. Electric trim wasn't disconnected until multiple uncorrected unscheduled MCAS activations had pushed the stab to nearly full nose-down trim.

That situation would be quite difficult to recover from at such a low altitude.
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Old May 15, 19, 1:20 pm
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Originally Posted by LarryJ View Post
The data that I've seen indicates that they (ET302) were in LVL CHG with a higher altitude selected on the MCP. That puts the autothrottles into N1 mode with an N1 setting of CLB (climb power). A/T was never disconnected. Thrust stayed at 91% N1 until a few seconds before the end of the flight. Indicated airspeed was as high as 390 KIAS. Electric trim wasn't disconnected until multiple uncorrected unscheduled MCAS activations had pushed the stab to nearly full nose-down trim.

That situation would be quite difficult to recover from at such a low altitude.
Ouch, that’s not good. I never saw the FMA data for Flight Director/Autopilot command modes but that really helps paint the picture.

Escalating downward trim with high climb thrust is a tough place to be. Bad things happen very quickly.
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Last edited by clubord; May 15, 19 at 1:35 pm
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Old May 15, 19, 1:53 pm
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Addis Ababa Bole International Airport is at 7,625 ft elevation? The ET plane was like at 3,000 ft above the ground?
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Old May 15, 19, 2:18 pm
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Originally Posted by BF263533 View Post
Addis Ababa Bole International Airport is at 7,625 ft elevation? The ET plane was like at 3,000 ft above the ground?
3,000 feet above ground level is a very low altitude in a 737.
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Old May 15, 19, 2:31 pm
  #1422  
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Originally Posted by clubord View Post

Very few here have the willingness to put aside their media driven interpretation of the events and be receptive to accept feedback from experienced pilots with knowledge of this aircraft.
Yes. Exactly. I would say the exact same thing.

The two or three "experienced pilots with knowledge of this aircraft" who post on this thread are counterbalanced by the "experienced pilots with knowledge of this aircraft" who have had to comment, anonymously for fear of retaliation, about the problems with the MAX.

Perhaps I would say that very few here have the willingness to put aside the Boeing talking points and be receptive to accept feedback from experienced pilots with knowledge of this aircraft.
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Old May 15, 19, 3:09 pm
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Originally Posted by DenverBrian View Post
I'm well aware. And you get to fly it for a while when it comes back before I set foot on it. <shrugs>

The question is: Did 350 people have to die for us to realize that there were flaws in how the 737MAX was brought to market? Could we have seen the potential dangers, identified and remedied them earlier in the process, and not have had to destroy 350 families and thousands of family members?
Question: Did 350 people have to die for us to realize all pilots -- not just US mainline ones -- should be trained and familiar with basic procedures and that the FO is and should be a co-pilot, with all that entails? Could we have seen the potential dangers, identified and remedied them earlier in the process? If you're going to avoid the 737MAX (as is your right to do) over misunderstanding what MCAS is or isn't, I presume you are also going to avoid airlines that use co-pilots with flight experience measured in the low hundreds rather than thousands of hours?
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Old May 15, 19, 3:11 pm
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Originally Posted by DenverBrian View Post
Yes. Exactly. I would say the exact same thing.

The two or three "experienced pilots with knowledge of this aircraft" who post on this thread are counterbalanced by the "experienced pilots with knowledge of this aircraft" who have had to comment, anonymously for fear of retaliation, about the problems with the MAX.

Perhaps I would say that very few here have the willingness to put aside the Boeing talking points and be receptive to accept feedback from experienced pilots with knowledge of this aircraft.
So, these "anonymous" pilots are afraid that Boeing going to retaliate against them. How is Boeing going to retaliate against them and how will they find out who these "anonymous pilots" are? Does Boeing control the internet as well? These conspiracy theories are really piling up here.
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Last edited by WineCountryUA; May 15, 19 at 7:23 pm Reason: discuss the issue, not the poster(s)
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Old May 15, 19, 3:52 pm
  #1425  
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Originally Posted by worldclubber View Post
But the question remains; Why do the allegedly badly trained "third-world" pilots have a problem with these runaways on the max but not on the ng? mcas could be the difference, or something else.
Same airline was crashing the NG even when the trim worked fine:

"the probable causes of the accident were the flight crew's mismanagement of the aircraft's speed, altitude, headings and attitude through inconsistent flight control inputs resulting in a loss of control and their failure to abide by CRM [Crew Resource Management] principles of mutual support and calling deviations"

Their training is not delivering basic airmanship and CRM.
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