MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
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Are you for real? So the aircraft is almost uncontrollable, you pull the yoke as hard as you can, you see the aircraft stabilizing itself adversely to what you would expect and then you say to yourself: "oh wait! it's not a continuous runaway! Everything is just fine!". Think for a minute: you in fact argue that these two accidents wouldn't have happened if the word "continuously" had been removed from the checklist. That's ridiculous!
And I seriously doubt many of us here would consistently succeed in an unexpected spate of multiple alarms and control difficulties in a sim, with no g's, no life at stake, no nothing.
But I'd welcome a sim or video showing I'm wrong.
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Experience taught me that pilots inexpectedly put in an unusual attitude with other things happening in the cockpit do *not* react like you suppose, sir. Hundreds of them, Europeans as well as Americans, low-time pilots as well as fighter pilots.
And I seriously doubt many of us here would consistently succeed in an unexpected spate of multiple alarms and control difficulties in a sim, with no g's, no life at stake, no nothing.
But I'd welcome a sim or video showing I'm wrong.
And I seriously doubt many of us here would consistently succeed in an unexpected spate of multiple alarms and control difficulties in a sim, with no g's, no life at stake, no nothing.
But I'd welcome a sim or video showing I'm wrong.
I am not saying that the crew had it easy and I am most certainly not saying that Boeing did good job on taking only one input to MCAS. I am saying that blaming one word in NNC is absurd. No matter how many lights were glittering, there was not a single one that should be linked to aircraft stabilizing itself in manual flight. I find it astonishing that in the ETH crew the low hour FO noticed what's going on. I wasn't paying much attention to this case but I still wonder if it was the captain who deliberately switched the stan trim cut out switches back to on position and doomed the aircraft.
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Runaway Stabilizer Condition: Uncommanded stabilizer trim movement occurs continuously. That's the leading statement in Boeing's checklist. At some point you have to realize that it might not be continuous but it's certainly doing it again, and again, and again, and again, and again, and again, for a total of 28 times. All in the same direction. Uncommanded. Twenty eight times. Every time making it harder and harder to control the aircraft. It shouldn't be that confusing that the stabilizer nose down movement is related to the very heavy nose that's completely out of trim.
I completely agree with your sentiments. As I alluded to in my earlier post; unfortunately that is not the case.Yet.
The stick shaker also has steps that need to be accomplished without reference to a manual. More of a procedure, but depending on semantics a stall recovery is a memory item. Boeing has defined steps to recover that will need to be completed from memory.
That said I agree with the overall message of your post. Where do you start with all the distractions.
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Pilotnik and misdagin, you guys are not putting yourselves in the place of the pilots that went down trying their best.
Obviously you perform a trim runaway memory item once pitch starts wandering against your commands. Didn't think we needed to cover that here.
The genesis of the loss of control had nothing to do with pitch or mcas. It was stick shaker and eventually overspeed. It was contradicting instrument indications. There were contradicting aural alarms.
Sorting these issues just seconds before the mcas did it's deed set the mind in a different mode than a simple trim runaway that we've all done in the sim and many of us on real life.
Been there done that and didn't even get a t-shirt my friend.
All you folks that are saying the aircraft was flyable and the checklist and memory items cover all the mcas issues haven't been flying very long or perhaps you have just been lucky.
Personally I feel the pilots did an average job of it and in 2019 that should be good enough. Is it ok with you if 99 crews out of 100 can safely operate? I think not.
I'll leave you with that. Stop blaming pilots. This aircraft has been grounded a lot longer than necessary If the problem were pilots or even pilot training.
Obviously you perform a trim runaway memory item once pitch starts wandering against your commands. Didn't think we needed to cover that here.
The genesis of the loss of control had nothing to do with pitch or mcas. It was stick shaker and eventually overspeed. It was contradicting instrument indications. There were contradicting aural alarms.
Sorting these issues just seconds before the mcas did it's deed set the mind in a different mode than a simple trim runaway that we've all done in the sim and many of us on real life.
Been there done that and didn't even get a t-shirt my friend.
All you folks that are saying the aircraft was flyable and the checklist and memory items cover all the mcas issues haven't been flying very long or perhaps you have just been lucky.
Personally I feel the pilots did an average job of it and in 2019 that should be good enough. Is it ok with you if 99 crews out of 100 can safely operate? I think not.
I'll leave you with that. Stop blaming pilots. This aircraft has been grounded a lot longer than necessary If the problem were pilots or even pilot training.
Last edited by jdawg; 28th Sep 2019 at 20:49.
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Some posts here seem to still be missing the obvious.
What's the crew to do when they discover that the manual wheels won't budge ?
BTW didn't some FAA test pilot say that it would take 40 s before the aircraft was doomed ?
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Runaway Stabilizer Condition: Uncommanded stabilizer trim movement occurs continuously. That's the leading statement in Boeing's checklist. At some point you have to realize that it might not be continuous but it's certainly doing it again, and again, and again, and again, and again, and again, for a total of 28 times. All in the same direction. Uncommanded. Twenty eight times. Every time making it harder and harder to control the aircraft. It shouldn't be that confusing that the stabilizer nose down movement is related to the very heavy nose that's completely out of trim.
You want to continue blaming pilots for failing to handle a system they didn't know existed (intermittent vs true continuous trim runaway) go ahead. I'm just trying to help you understand that many of us here are accounting for the fact that the crew experienced a lot more than a trim runaway.
Cheers
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When the trim moves nose down "by itself", the pilots will naturally respond by trimming nose up. Probably barely noticing it. It looks just like the STS they work against every single takeoff... because it IS the STS...except that it is moving in the opposite direction. So much so, that the surviving crew wrote it up that way. It does NOT look like the stab trim runaway we were (once, long ago) trained for. Boeing could not have masked the problem any more effectively if they had tried.
If I "perform[ed] a trim runaway memory item once pitch starts wandering against [my] commands", I would do so every single flight.
I'll do it tomorrow, just for the heck of it.
Last edited by Takwis; 28th Sep 2019 at 22:09.
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Repeating the obvious is the essence of teaching.
Some posts here seem to still be missing the obvious.
This point has been covered a long time ago here.
What's the crew to do when they discover that the manual wheels won't budge ?
BTW didn't some FAA test pilot say that it would take 40 s before the aircraft was doomed ?
Some posts here seem to still be missing the obvious.
This point has been covered a long time ago here.
What's the crew to do when they discover that the manual wheels won't budge ?
BTW didn't some FAA test pilot say that it would take 40 s before the aircraft was doomed ?
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I know what you're trying to say here, but you're actually making an argument that the pilots should have been trimming - to use your word - habitually every time that MCAS made a trim input opposite of what they wanted. We know that the Main Electric Trim stopped and countered MCAS every time it was used. Yet two of the pilots (Ethiopian Captain, Lion Air First Officer) failed to do so aggressively enough thus resulting in a loss of control. This is really one of the great mysteries surrounding these accidents.
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And, despite all of that, we still have people blaming the pilots.
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So, Tomaski, they trimmed, as they should have, and it responded to their commands, as it should have, but their commands were not aggressive enough. That still doesn't look like a runaway stab trim. That looks like "WTF is wrong with this damned thing!"
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I am looking again for a comment or article I read some time ago which IF my recollection is correct, 3 FAA employed pilots were set up in the Boeing ? Eng ? sim with the ethopia scene. They knew what and probably when to expect and the ' cure' Two of the pilots ' saved ' the plane, ONE did not. The two who saved the plane were ex military ( fighter ? or transport ? ) pilots. The one who failed was or had been a many hour Airline type.
And as I recall ( please correct ) - the ethopia takeoff was at 7k MSL on a warm day, with rising terrain in front.
IF i am correct- then consider that a 66 percent survival rate under ideal conditions does not give anyone a warm fuzzy . . .
And as I recall ( please correct ) - the ethopia takeoff was at 7k MSL on a warm day, with rising terrain in front.
IF i am correct- then consider that a 66 percent survival rate under ideal conditions does not give anyone a warm fuzzy . . .
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As you previously said, pilot trim inputs typically are habitual, even if some system on the 737 is making its own inputs in the opposite direction. Three pilots (penultimate Lion Air 610 Captain & FO, accident Lion Air 610 Captain) managed to keep up with the trim, albeit with some difficulty. Two pilots did not. I am very curious as to what made the difference. I have my own theory, but I don't have any data to back it up.
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I admire your 32 year old condescending tone and yes they did. The previous Lion flight was a good example. What you do is you generalize based on your short experience. There are numerous captains all over the world who lose themselves in a simple engine fire drill on a simulator or are unable to make a manual ils approach in raw data without destabilizing. Some of them are your friends and you don’t even know until you have a session with them. Sometimes they are let through opc’s because of pilot shortage, sometimes it’s because they are old friends and it’s uncomfortable to tell them the truth that they no longer have the perception. The problem is bigger than just a multitude of lights and alerts. We developed a system in which it is almost a heresy to say that a pilot did something wrong and because of this we put ourselves into an illusion that Boeing, Airbus or whatever needs to build a better plane that will never shine more than one light or sound more than one alert at a time so that a captain who haven’t read an FCOM or FCTM since his upgrade 15 years ago could face it.
The test pilot said it would take 40s to crash the aircraft with MCAS corrupted if NO ACTIONS are taken which. I think we all realise this. However, it is irrelevant to this discussion as the actions WERE taken and they were good until reversed.
Did you fail an Airbus type rating or something? Is that why you are defending Boeing and blaming the crews action? It's ok if you did.
I don't need to tell you how many years but it's in decades and I have yet to witness a sim partner fowl up an engine fire drill or destabilize a single engine approach. Perhaps you're right and the day just hasn't come yet. Those instances we know what's coming and it aids our performance. I'm sure you'd agree.
So you admit a briefed sim session can end badly but not a real emergency with a system no one knew of while sitting next to a low time pilot with multiple contradicting warnings and indications. Ok. Got it.
No one wants to read our back and forth so just do us all a favor and say you'll rescind the blame and wait for the final report.
Or, you can just allege condescension and proceed to condescend yourself lol
Good luck to your fellow pilots
Sensor Failures
With the MAX we have two AoA failures that both triggered the stick shaker and several actuations of MCAS.
Blocked pitots took down AF447, and others.
Blocked statics have taken down at least two, Lima and Santo Domingo.
AH failure took down a 747 out of Mumbai.
Others with better memories likely know of more.
None of these crews diagnosed the failure in time. Often the captain will prefer his instrument readings to those on the copilot side or the standby. But common factors, such as tape or icing can take out entire sensor suites.
Crews get presented with engine failures on recurrent sim checks. Sensor failures should also be included, but of course this will call for more sim time to the great distress of bean counters.
Time to buy stock in sim manufacturers. They will be getting a bunch more business
Blocked pitots took down AF447, and others.
Blocked statics have taken down at least two, Lima and Santo Domingo.
AH failure took down a 747 out of Mumbai.
Others with better memories likely know of more.
None of these crews diagnosed the failure in time. Often the captain will prefer his instrument readings to those on the copilot side or the standby. But common factors, such as tape or icing can take out entire sensor suites.
Crews get presented with engine failures on recurrent sim checks. Sensor failures should also be included, but of course this will call for more sim time to the great distress of bean counters.
Time to buy stock in sim manufacturers. They will be getting a bunch more business
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I know what you're trying to say here, but you're actually making an argument that the pilots should have been trimming - to use your word - habitually every time that MCAS made a trim input opposite of what they wanted. We know that the Main Electric Trim stopped and countered MCAS every time it was used. Yet two of the pilots (Ethiopian Captain, Lion Air First Officer) failed to do so aggressively enough thus resulting in a loss of control. This is really one of the great mysteries surrounding these accidents.
Also, to help stall recovery, the elevator feel system makes it harder to pull the control column when the AoA is over a certain value, which could have made things even harder on the accident flights, compared to just being severely out of trim at high speed.
Reacting as if it was a trim runaway would have stopped the problem. The plane could have been flown, almost 100% normally, to a safe landing. That's exactly what happened on the flight that the jump seater identified the problem as a runaway trim - the crew turned the trim off using the stab trim cutout switches and continued to their destination. I'm not advocating continuing to your destination after a stab trim problem but their actions show that it's fully controllable once the appropriate steps are taken.
https://theaircurrent.com/aviation-s...-social-media/
Having to apply significant force to the control column to counter the out of trim stabilizer might make it difficult to use the thumb switches. For example the Ethiopian captain asked the FO to help him trim during the second MCAS activation, which many people here found puzzling. Maybe the pilot flying had to hold the control column like this:
Also, to help stall recovery, the elevator feel system makes it harder to pull the control column when the AoA is over a certain value, which could have made things even harder on the accident flights, compared to just being severely out of trim at high speed.
Also, to help stall recovery, the elevator feel system makes it harder to pull the control column when the AoA is over a certain value, which could have made things even harder on the accident flights, compared to just being severely out of trim at high speed.
