Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Thu Mar 14, 2019 10:16 am

ETOPS certification has to do with failure rate, and as far as I'm aware there hasn't been an unusual number of engine failures on the Max.
Between Aug 17 2018 and Feb 13 2019 there have been 5 in flight shutdowns and 4 cases of engine failure (unscheduled engine removal) caught on the ground. CFM is dictating 100 hr inspections and they are not catching all the issues. The transfer gearbox bearings are failing at an alarming rate and CFM has no idea why - or how to fix them.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Thu Mar 14, 2019 10:46 am

Back to the topic at hand.....

Here is the bulliten issued by Boeing to all operators and made mandentory by an FAA AD after the Lion air accident....


"On Nov 7th 2018 Boeing issued an Operations Manual Bulletin (OMB) to all Boeing 737 MAX Operators stating that the investigation into the crash of PK-LQP found one of the Angle of Attack Sensors had provided incorrect readings, which could cause the aircraft's trim system to uncommandedly trim nose down in order to avoid a stall during manual flight. The OMB directs "operators to existing flight crew procedures to address circumstances where there is erroneous input from an AOA sensor." The OMB reiterates the Stabilizer Runaway non-normal checklist.

The flight Crew Operations Manual Bulletin TBC-19 reads:

The Indonesian National Transportation Safety Committee has indicated that Lion Air flight 610 experienced erroneous AOA data. Boeing would like to call attention to an AOA failure condition that can occur during manual flight only.

This bulletin directs flight crews to existing procedures to address this condition. In the event of erroneous AOA data, the pitch trim system can trim the stabilizer nose down in increments lasting up to 10 seconds. The nose down stabilizer trim movement can be stopped and reversed with the use of the electric stabilizer trim switches but may restart 5 seconds after the electric stabilizer trim switches are released. Repetitive cycles of uncommanded nose down stabilizer continue to occur unless the stabilizer trim system is deactivated through use of both STAB TRIM CUTOUT switches in accordance with the existing procedures in the Runaway Stabilizer NNC. It is possible for the stabilizer to reach the nose down limit unless the system inputs are counteracted completely by pilot trim inputs and both STAB TRIM CUTOUT switches are moved to CUTOUT.

Additionally, pilots are reminded that an erroneous AOA can cause some or all of the following indications and effects:

- Continuous or intermittent stick shaker on the affected side only.
- Minimum speed bar (red and black) on the affected side only.
- Increasing nose down control forces.
- Inability to engage autopilot.
- Automatic disengagement of autopilot.
- IAS DISAGREE alert.
- ALT DISAGREE alert.
- AOA DISAGREE alert (if the AOA indicator option is installed)
- FEEL DIFF PRESS light.

In the event an uncommanded nose down stabilizer trim is experienced on the 737 - 8 / - 9, in conjunction with one or more of the above indications or effects, do the Runaway Stabilizer NNC ensuring that the STAB TRIM CUTOUT switches are set to CUTOUT and stay in the CUTOUT position for the remainder of the flight."
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by co-joe » Thu Mar 14, 2019 10:59 am

FICU wrote:
Wed Mar 13, 2019 9:03 pm
The more I read about this MCAS system the more I wonder why it isn’t handled as a stab trim runaway by disabling it with the stab trim cut off switches. Or does this come down to crew training in other parts of the world on this jet that isn’t adequate compared to the US and Canada?
I wonder that myself. So the mcas system is giving you an un-commanded nose down trim. You disengage the autoflight system and the harder you pull back the more that wheel spins forward. Without even knowing what mcas is, wouldn't you immediately be thinking runaway trim?
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by FICU » Thu Mar 14, 2019 11:39 am

boeingboy wrote:
Thu Mar 14, 2019 9:50 am
The more I read about this MCAS system the more I wonder why it isn’t handled as a stab trim runaway by disabling it with the stab trim cut off switches. Or does this come down to crew training in other parts of the world on this jet that isn’t adequate compared to the US and Canada?
That is exactly what the procedure is. That is what Boeing re-enforced after Lion air went in and that is exactly what the previous 3 Lion air crews did when it went funky on the pervious 3 legs - and they all made it to destination just fine. Why the 4th crew didn't do that is a mystery.
Interesting. So, in the case of Lion Air it was a mishandled stab trim runaway. They would also notice the stab trim wheel trimming nose down uncontrollably so it's not like it's a hidden system that the crew wouldn't have known what was happening. If it's the same with the Ethiopian crash it could again come down to a mishandled trim runway.

Does that require a need to ground the fleet other than for public optics?
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Thu Mar 14, 2019 11:49 am

Does that require a need to ground the fleet other than for public optics?
That's exactly my point.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by rookiepilot » Thu Mar 14, 2019 11:59 am

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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by FICU » Thu Mar 14, 2019 12:04 pm

Sounds like they need to have an alternate source of AoA to cross compare to the one being read by the MCAS before the MCAS activates.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by BTD » Thu Mar 14, 2019 1:39 pm

FICU wrote:
Thu Mar 14, 2019 11:39 am
boeingboy wrote:
Thu Mar 14, 2019 9:50 am
The more I read about this MCAS system the more I wonder why it isn’t handled as a stab trim runaway by disabling it with the stab trim cut off switches. Or does this come down to crew training in other parts of the world on this jet that isn’t adequate compared to the US and Canada?
That is exactly what the procedure is. That is what Boeing re-enforced after Lion air went in and that is exactly what the previous 3 Lion air crews did when it went funky on the pervious 3 legs - and they all made it to destination just fine. Why the 4th crew didn't do that is a mystery.
Interesting. So, in the case of Lion Air it was a mishandled stab trim runaway. They would also notice the stab trim wheel trimming nose down uncontrollably so it's not like it's a hidden system that the crew wouldn't have known what was happening. If it's the same with the Ethiopian crash it could again come down to a mishandled trim runway.

Does that require a need to ground the fleet other than for public optics?
The problem is that with the flaps retracted the trim wheel moves at a slower rate. And at that time shortly after takeoff the speed trim system is often active anyway. And the MCAS will command trim for 10secs then stop before commanding it again. So it doesn’t exactly look like a trim runaway at first glance. It was overcome the previous flight to the lion air accident by the previous crew moving the cutout switches off, but throw in the stick shaker at rotation and it could become confusing quickly.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by RVR6000 » Thu Mar 14, 2019 2:10 pm

An unreliable airspeed along with a stick shaker going (stall indication) and MCAS stab trim runaway all at a low altitude can become a hand full to handle.

I’m not sure if the MCAS characteristics are even program in the SIM for training.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by Eric Janson » Thu Mar 14, 2019 2:26 pm

BMLtech wrote:
Thu Mar 14, 2019 9:34 am
If MCAS were to be activated due to erroneous AOA data I'm curious if other false warnings would be presented that could cause confusion. Is there the possibility of a false stall warning/stick shaker at the same time?
I believe this happened on a number of sectors prior to the Lion Air crash.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Thu Mar 14, 2019 2:32 pm

The problem is that with the flaps retracted the trim wheel moves at a slower rate. And at that time shortly after takeoff the speed trim system is often active anyway. And the MCAS will command trim for 10secs then stop before commanding it again. So it doesn’t exactly look like a trim runaway at first glance. It was overcome the previous flight to the lion air accident by the previous crew moving the cutout switches off, but throw in the stick shaker at rotation and it could become confusing quickly.
This is exactly what happened to the crew on the previous flight. They got stick shaker at rotation. MCAS does not start trimming until the flaps are up and it doesn't just keep trimming down. If the crew trims up with the control column switch it will trim nose up. It will counteract the MCAS. This is why the accident flight was not only descending but climbing as well. For some reason at the end of the flight they all but stopped trying to counter the down trim with up trim.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Thu Mar 14, 2019 2:35 pm

Read it yourself.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Thu Mar 14, 2019 2:52 pm

Here is what happened on the previous flight to the accident flight:


"About 400 feet, the PIC noticed on the Primary Flight Display (PFD)13 that the IAS DISAGREE warning appeared and the stick shaker activated. The FDR showed the stick shaker activated during the rotation. Following that indication, the PIC maintained a pitch of 15° and the existing takeoff thrust setting. The stick shaker remained active throughout the flight.

The PIC handed over control to the SIC and announced “memory item airspeed unreliable”. After the transfer of control, the PIC cross checked the PFDs with the standby instrument and determined that the left PFD had the problem. The PIC then switched on the right flight director (FD) so the SIC would have a normal display.

While handling the problem, the PIC instructed the SIC to continue acceleration and flap retraction as normal. The PIC commanded the SIC to follow FD command and re-trim the aircraft as required. The PIC noticed that as soon the SIC stopped trim input, the aircraft was automatically trimming aircraft nose down (AND).

After three automatic AND trim occurrences, the SIC commented that the control column was too heavy to hold back. At 14:25:46 UTC, the PIC declared “PAN PAN” to the Denpasar Approach controller due to instrument failure and requested to maintain runway heading. The Denpasar Approach controller acknowledged the message and approved the pilot request. A few second later, the Denpasar Approach controller asked the LNI043 whether he wanted to return to Denpasar and the pilot responded “standby”.

At 14:28:28 UTC, the PIC moved the STAB TRIM switches to CUT OUT. The PIC re-engaged the STAB TRIM switches to NORMAL, but almost immediately the problem re-appeared. The PIC then moved the STAB TRIM switches back to CUT OUT and continued with manual trim without auto-pilot until the end of the flight.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by BTD » Thu Mar 14, 2019 4:07 pm

boeingboy wrote:
Thu Mar 14, 2019 2:32 pm
The problem is that with the flaps retracted the trim wheel moves at a slower rate. And at that time shortly after takeoff the speed trim system is often active anyway. And the MCAS will command trim for 10secs then stop before commanding it again. So it doesn’t exactly look like a trim runaway at first glance. It was overcome the previous flight to the lion air accident by the previous crew moving the cutout switches off, but throw in the stick shaker at rotation and it could become confusing quickly.
This is exactly what happened to the crew on the previous flight. They got stick shaker at rotation. MCAS does not start trimming until the flaps are up and it doesn't just keep trimming down. If the crew trims up with the control column switch it will trim nose up. It will counteract the MCAS. This is why the accident flight was not only descending but climbing as well. For some reason at the end of the flight they all but stopped trying to counter the down trim with up trim.
Yes indeed it is, as I mentioned in my own post. It was a very dynamic situation. Perhaps the crew the day before was really switched on, or perhaps the captain just happened to see the IAS disagree indication leading them to the right conclusion.

However, the stick shaker at rotation throws a wrench in the entire operation. I know my first response is not to think AOA failure, but to follow the stall guidance of the AOM and QRH which includes checking the flap setting if it occurs during takeoff.

Certainly makes for a messy situation. Apparently recoverable as demonstrated by the crew the previous day, but certainly not how you want to start off your flight.

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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by sportingrifle » Fri Mar 15, 2019 12:57 am

One of the things that drives me nuts is how the airframer sales people sell these airplanes to their airline customers - usually bean counters and MBA's.
"Really easy to fly, no problem bringing low time cadets on board."
" Reduced training costs. All your XXX pilots need is an internet based differences course."
" There is nothing to it, you can covert your XXX pilots with a short course."
But let one of their nearly self driving airplanes create a new underground aluminum deposit and the same airframers say "Not our fault, your guys didn't fly it like our test pilots would have."

Boeing (and many posters) say "Hey, it's just a trim runaway. Do the drill and all is good." But this is not the simple trim runaway that the QRH contemplates. It starts with a stall warning stick shaker shortly after lift off. Close to the ground this will, and should consume both pilots undivided attention. After a number of seconds they realise that the airplane hasn't stalled and they start figuring out that they may have an airspeed and/or AOA problem. This is a second problem to deal with on top of the first. And they can't shut the &%$#@ stick shaker off once they realise that it may be spurious. The PM will be frantically scanning the panel to try and find some clue what is going on. And this whole time, among the din of the stick shaker, crews concern for the airplanes flight path, and the confusing instrument indications, MCAS has been intermittently dialing in nose down trim. Not steadily, in a calm cockpit at altitude like the QRH contemplates. But intermittently in the background of chaos, noise, and confusion. At some point, well past when it would have been timely, the task saturated PF realizes that the trim is working against him/her and the stab cutout switches get turned off. (hopefully)

But the shitshow isn't over. Because of everything else going on, this took too long and the airplane is way out of trim. The Lion Air crew reportedly had 60 KG of back pressure on the yoke. Close to the ground, and relying on the lifting component of the underslung engines to help keep the nose up, the crew do not dare reduce power. Now the crew needs to manually trim the airplane, but the airplane is way, way off its trim speed. The B737 QRH makes reference to the large forces that may be required to break free a servo clutch:
"3 If needed:Use force to cause the disconnect clutch to disengage. Approximately 1/2 turn of the stabilizer trim wheel may be needed.
Note:A maximum two-pilot effort on the trim wheels will not cause a cable or system failure."

Worse, the "Manual Stabilizer Trim" section of the Boeing FCTM talks about the air loads on a grossly out of trim stab requiring a speed change to reduce the force required to manually trim:
"Excessive air loads on the stabilizer may require effort by both pilots to correct mis-trim. In extreme cases it may be necessary to aerodynamically relieve the air loads to allow manual trimming. Accelerate or decelerate towards the in-trim speed while attempting to trim manually."

Sweet Jesus how did this thing get certified? A guy (or petite gal) has a 60 KG+ force on the yoke trying to stop the airplane from impaling itself into the hard ground just a few thousand feet below, and now he/she has to brute force trim the airplane as well, requiring involved coordination with the PM. Still with all the stick shakers, aural warnings, goofy instrument readings, and whatever else is happening to distract the crew and making communication almost impossible. It is not hard to see how quickly it becomes overwhelming.

In addition to a fix for the airplane, if they keep the MCAS system (instead of designing a whole new wing or tail for the airplane), they will have to train the pilots who fly it to deal with its failure. Right now, there is not a single Max pilot in the world who has been trained for this failure because - there isn't a single simulator in the world that can replicate it. But when they do, all those pilots that claimed "it's just a trim runaway" are going to have a very eye opening simulator session.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by Eric Janson » Fri Mar 15, 2019 1:22 am

This isn't looking good for Boeing....

https://twitter.com/Reuters/status/1106 ... ca-73.html

Anyone still think grounding the fleet is an overreaction?
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Fri Mar 15, 2019 6:54 am

Yes.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by ktcanuck » Fri Mar 15, 2019 6:55 am

sportingrifle wrote:
Fri Mar 15, 2019 12:57 am
One of the things that drives me nuts is how the airframer sales people sell these airplanes to their airline customers - usually bean counters and MBA's.
"Really easy to fly, no problem bringing low time cadets on board."
" Reduced training costs. All your XXX pilots need is an internet based differences course."
" There is nothing to it, you can covert your XXX pilots with a short course."
But let one of their nearly self driving airplanes create a new underground aluminum deposit and the same airframers say "Not our fault, your guys didn't fly it like our test pilots would have."

Boeing (and many posters) say "Hey, it's just a trim runaway. Do the drill and all is good." But this is not the simple trim runaway that the QRH contemplates. It starts with a stall warning stick shaker shortly after lift off. Close to the ground this will, and should consume both pilots undivided attention. After a number of seconds they realise that the airplane hasn't stalled and they start figuring out that they may have an airspeed and/or AOA problem. This is a second problem to deal with on top of the first. And they can't shut the &%$#@ stick shaker off once they realise that it may be spurious. The PM will be frantically scanning the panel to try and find some clue what is going on. And this whole time, among the din of the stick shaker, crews concern for the airplanes flight path, and the confusing instrument indications, MCAS has been intermittently dialing in nose down trim. Not steadily, in a calm cockpit at altitude like the QRH contemplates. But intermittently in the background of chaos, noise, and confusion. At some point, well past when it would have been timely, the task saturated PF realizes that the trim is working against him/her and the stab cutout switches get turned off. (hopefully)

But the shitshow isn't over. Because of everything else going on, this took too long and the airplane is way out of trim. The Lion Air crew reportedly had 60 KG of back pressure on the yoke. Close to the ground, and relying on the lifting component of the underslung engines to help keep the nose up, the crew do not dare reduce power. Now the crew needs to manually trim the airplane, but the airplane is way, way off its trim speed. The B737 QRH makes reference to the large forces that may be required to break free a servo clutch:
"3 If needed:Use force to cause the disconnect clutch to disengage. Approximately 1/2 turn of the stabilizer trim wheel may be needed.
Note:A maximum two-pilot effort on the trim wheels will not cause a cable or system failure."

Worse, the "Manual Stabilizer Trim" section of the Boeing FCTM talks about the air loads on a grossly out of trim stab requiring a speed change to reduce the force required to manually trim:
"Excessive air loads on the stabilizer may require effort by both pilots to correct mis-trim. In extreme cases it may be necessary to aerodynamically relieve the air loads to allow manual trimming. Accelerate or decelerate towards the in-trim speed while attempting to trim manually."

Sweet Jesus how did this thing get certified? A guy (or petite gal) has a 60 KG+ force on the yoke trying to stop the airplane from impaling itself into the hard ground just a few thousand feet below, and now he/she has to brute force trim the airplane as well, requiring involved coordination with the PM. Still with all the stick shakers, aural warnings, goofy instrument readings, and whatever else is happening to distract the crew and making communication almost impossible. It is not hard to see how quickly it becomes overwhelming.

In addition to a fix for the airplane, if they keep the MCAS system (instead of designing a whole new wing or tail for the airplane), they will have to train the pilots who fly it to deal with its failure. Right now, there is not a single Max pilot in the world who has been trained for this failure because - there isn't a single simulator in the world that can replicate it. But when they do, all those pilots that claimed "it's just a trim runaway" are going to have a very eye opening simulator session.
Exactly!
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by rookiepilot » Fri Mar 15, 2019 7:34 am

Eric Janson wrote:
Fri Mar 15, 2019 1:22 am
This isn't looking good for Boeing....

https://twitter.com/Reuters/status/1106 ... ca-73.html

Anyone still think grounding the fleet is an overreaction?
Gee; Trump's comments aren't looking so foolish, now......
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by MrWings » Fri Mar 15, 2019 7:53 am

rookiepilot wrote:
Fri Mar 15, 2019 7:34 am
Gee; Trump's comments aren't looking so foolish, now......
said no one EVER!
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by complexintentions » Fri Mar 15, 2019 12:33 pm

Eric Janson wrote:
Fri Mar 15, 2019 1:22 am
This isn't looking good for Boeing....

https://twitter.com/Reuters/status/1106 ... ca-73.html

Anyone still think grounding the fleet is an overreaction?
Yes.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by atc_is_god » Fri Mar 15, 2019 12:48 pm

Can anyone confirm that 737 MAX aircraft were repositioned from YVR to YWG yesterday? (Mar 14)
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by tsgas » Fri Mar 15, 2019 1:00 pm

MrWings wrote:
Fri Mar 15, 2019 7:53 am
rookiepilot wrote:
Fri Mar 15, 2019 7:34 am
Gee; Trump's comments aren't looking so foolish, now......
said no one EVER!
Speak for yourself.
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by boeingboy » Fri Mar 15, 2019 1:02 pm

One of the things that drives me nuts is how the airframer sales people sell these airplanes to their airline customers - usually bean counters and MBA's.
"Really easy to fly, no problem bringing low time cadets on board."
" Reduced training costs. All your XXX pilots need is an internet based differences course."
" There is nothing to it, you can covert your XXX pilots with a short course."
But let one of their nearly self driving airplanes create a new underground aluminum deposit and the same airframers say "Not our fault, your guys didn't fly it like our test pilots would have."

Boeing (and many posters) say "Hey, it's just a trim runaway. Do the drill and all is good." But this is not the simple trim runaway that the QRH contemplates. It starts with a stall warning stick shaker shortly after lift off. Close to the ground this will, and should consume both pilots undivided attention. After a number of seconds they realise that the airplane hasn't stalled and they start figuring out that they may have an airspeed and/or AOA problem. This is a second problem to deal with on top of the first. And they can't shut the &%$#@ stick shaker off once they realise that it may be spurious. The PM will be frantically scanning the panel to try and find some clue what is going on. And this whole time, among the din of the stick shaker, crews concern for the airplanes flight path, and the confusing instrument indications, MCAS has been intermittently dialing in nose down trim. Not steadily, in a calm cockpit at altitude like the QRH contemplates. But intermittently in the background of chaos, noise, and confusion. At some point, well past when it would have been timely, the task saturated PF realizes that the trim is working against him/her and the stab cutout switches get turned off. (hopefully)

But the shitshow isn't over. Because of everything else going on, this took too long and the airplane is way out of trim. The Lion Air crew reportedly had 60 KG of back pressure on the yoke. Close to the ground, and relying on the lifting component of the underslung engines to help keep the nose up, the crew do not dare reduce power. Now the crew needs to manually trim the airplane, but the airplane is way, way off its trim speed. The B737 QRH makes reference to the large forces that may be required to break free a servo clutch:
"3 If needed:Use force to cause the disconnect clutch to disengage. Approximately 1/2 turn of the stabilizer trim wheel may be needed.
Note:A maximum two-pilot effort on the trim wheels will not cause a cable or system failure."

Worse, the "Manual Stabilizer Trim" section of the Boeing FCTM talks about the air loads on a grossly out of trim stab requiring a speed change to reduce the force required to manually trim:
"Excessive air loads on the stabilizer may require effort by both pilots to correct mis-trim. In extreme cases it may be necessary to aerodynamically relieve the air loads to allow manual trimming. Accelerate or decelerate towards the in-trim speed while attempting to trim manually."

Sweet Jesus how did this thing get certified? A guy (or petite gal) has a 60 KG+ force on the yoke trying to stop the airplane from impaling itself into the hard ground just a few thousand feet below, and now he/she has to brute force trim the airplane as well, requiring involved coordination with the PM. Still with all the stick shakers, aural warnings, goofy instrument readings, and whatever else is happening to distract the crew and making communication almost impossible. It is not hard to see how quickly it becomes overwhelming.

In addition to a fix for the airplane, if they keep the MCAS system (instead of designing a whole new wing or tail for the airplane), they will have to train the pilots who fly it to deal with its failure. Right now, there is not a single Max pilot in the world who has been trained for this failure because - there isn't a single simulator in the world that can replicate it. But when they do, all those pilots that claimed "it's just a trim runaway" are going to have a very eye opening simulator session.
JEEZ! - you should be a writer for Hollywood.

That is such an overdramatized sum of the events. Seriously - you don't think a professional crew can deal with 2 or 3 things that come at them in stages over 13 min? I guess then by your account the crew of Quantas 32 should have met their maker about a hundred times. Prioritize - I don't care what's going on - but if my airplane is trying to trim me into the ground constantly - it would not take very long to realize that is the priority and to disable it. By that time - they had already figured out the stick shaker was a false indication as was the airspeed disagree - so all they had to do was cut out the stab trim when it started running amuck. Instead they spent the next 10 min overriding it with the trim switch - when they should have just isolated it all together. During the whole time they were able to takeoff, climb out, change course, and acknowledge ATC instructions.

Not a fun day at the office - but boys and girls - this is where we make the big bucks.

I wonder if some of you have actually read the Lion air report?
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Re: Ethiopian Airlines: 'No survivors' on crashed Boeing 737 max

Post by '97 Tercel » Fri Mar 15, 2019 2:11 pm

this is where we make the big bucks.
This is where you earn your flat pay!
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