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Ethiopian 737 MAX 8 crash

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Ethiopian 737 MAX 8 crash

Old 05-12-2019, 01:48 PM
  #601  
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Originally Posted by JohnBurke View Post
Do you know why they couldn't move the trim?

Because they were accelerating continuously. Step one is fly the airplane.

They knew the procedure. They simply did not do what they were supposed to do.

Have you actually read the report? It's very clear.

https://assets.documentcloud.org/doc...X-Ethiopia.pdf
Yes. And it wasn’t that they didn’t follow their training. The training wasn’t there.
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Old 05-12-2019, 01:57 PM
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Originally Posted by pangolin View Post
Yes. And it wasn’t that they didn’t follow their training. The training wasn’t there.
You haven't read the report.

They verbalized the problem and what to do about it.

They certainly did have the training, and the procedure for unwanted stab trim hasn't changed; the steps are the same, the actions are the same, and it's not like it's an obscure unknown. The cause is irrelevant as the procedure remains the same.

They verbalized it: we know this because it's on the CVR. They did the procedure.

Then they undid it, let the aircraft accelerate well beyond the certification limitations for the airplane, and drove themselves into the ground.
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Old 05-12-2019, 09:01 PM
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Originally Posted by JohnBurke View Post
You haven't read the report.

They verbalized the problem and what to do about it.

They certainly did have the training, and the procedure for unwanted stab trim hasn't changed; the steps are the same, the actions are the same, and it's not like it's an obscure unknown. The cause is irrelevant as the procedure remains the same.

They verbalized it: we know this because it's on the CVR. They did the procedure.

Then they undid it, let the aircraft accelerate well beyond the certification limitations for the airplane, and drove themselves into the ground.
The porpoise maneuver to unload the stab was not taught. I agree they should have pulled the power back. However the full recovery was not trained and will only be trained for everyone after Boeing releases it.
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Old 05-12-2019, 11:40 PM
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Originally Posted by pangolin View Post
The porpoise maneuver to unload the stab was not taught. I agree they should have pulled the power back. However the full recovery was not trained and will only be trained for everyone after Boeing releases it.
There was no need to "porpoise" anything. Counter the trim action to stop trim; it can be done with the control wheel trim switch. Cutoff stab trim. Adjust trim manually. Maintain speed.

Even a caveman can do it. It doesn't matter why the trim moved uncommanded; the procedure is the same. Not really rocket science.
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Old 05-13-2019, 06:50 AM
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Originally Posted by 2StgTurbine View Post
There seem to be 2 camps.

1. The airplane is broken and shouldn't not have been certificated.

2. The plane has flaws, but a well trained crew should be able to overcome those flaws.
Boeing tried to fall back and dig in on position #2. It didn't work out for them. It won't work out for them in the future, if they want to sell airplanes outside of the US. Airbus will happily build planes for the LCD pilot.

As I've said before I don't think US Max pilots would have crashed, but it just so happened that they were all in the upper crust of US airline aviation, which has a deeper pool of pilot experience to draw from in the first place. Not so sure I could say the same about entry-level US regional pilots (although at least they have 1500 hours).

Last edited by rickair7777; 05-13-2019 at 08:49 AM. Reason: typo
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Old 05-13-2019, 08:16 AM
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Originally Posted by 2StgTurbine View Post
There seem to be 2 camps.

1. The airplane is broken and shouldn't not have been certificated.

2. The plane has flaws, but a well trained crew should be able to overcome those flaws.
It's definitely 1, Boeing gamed the certification process illegally. The crashes may have been because of bad crews, but that's not going to matter at this point.
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Old 05-13-2019, 04:20 PM
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Originally Posted by JohnBurke View Post
There was no need to "porpoise" anything. Counter the trim action to stop trim; it can be done with the control wheel trim switch. Cutoff stab trim. Adjust trim manually. Maintain speed.

Even a caveman can do it. It doesn't matter why the trim moved uncommanded; the procedure is the same. Not really rocket science.
You clearly have no clue about aerodynamic loads and the jack screw.
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Old 05-13-2019, 05:44 PM
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Originally Posted by pangolin View Post
You clearly have no clue about aerodynamic loads and the jack screw.
Really?

Relay the procedure to me, as it's been spelled out for decades in each flight manual, for doing a "porpoise maneuver."

How about the procedure for unwanted trim, which really hasn't changed in decades?

There are two essential elements of that procedure that are basic airmanship, and basic to the procedure: once the stab trim has been cut off, don't close the switches again, and a change in airspeed away from trimmed speed will make the matter worse, particularly an increase in speed.

There was no need for a "porpoise maneuver." There was a very definite need to maintain their airspeed, and to not re-engage the stab trim. Fail to support those two needs proved fatal. A "porpoise" maneuver was never necessary to fly the aircraft; it was flyable. The aircrew made it unflyable.
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Old 05-13-2019, 09:33 PM
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..I think Boeing has really just now found out about the reliance to automation, and the cultural issues, that exist at some of these Asian carriers..Neither one of these accidents, discussed here, would have happened in the US, as the crews flying these planes there are at a completely different level of experience, and competency..I bet Boeing did not see this coming, as their planes are designed, and flown, to meet the standards that exist in the US..

..BTW you will not see me, or my family, traveling on any of those Asian airlines..We will drive or take a ship..

Fly safe,
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Old 05-14-2019, 05:35 AM
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Although the name implies what it is about, I would be interested in the details of this porpoise maneuver.
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