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Texasbound 03-23-2022 07:44 AM


Originally Posted by GogglesPisano (Post 3393503)
Yes. We practiced this in the sim -- after a 20 minute brief including a powerpoint showing the position of the jackscrew relative to the stab axis and the forces from the elevator. There is no way we could have figured this out in 10s.

Wow, so after all that training you don't realize that using the manual wheel is at the end of the checklist? If you start the memory items withing 10 seconds you will not be wildly out of trim when doing the last part. It's called flying.

Control column............................................ .....Hold firmly

Autopilot (if engaged).......................................... .Disengage

Autothrottle (if engaged)........................................Di sengage

Control column and thrust levers..........................Control airplane
pitch attitude and airspeed

Main Electric
Stabilizer trim.............................................R educe control
column forces

If the runaway stops after the autopilot is disengaged:

Do not re-engage the autopilot or autothrottle.

----

If the runaway continues after the autopilot is disengaged:

STAB TRIM CUTOUT
switches (both)............................................ ....CUTOUT

If the runaway continues:
Stabilizer
trim wheel........................................Grasp and hold

Hedley 03-23-2022 08:06 AM


Originally Posted by Texasbound (Post 3393529)
Wow, so after all that training you don't realize that using the manual wheel is at the end of the checklist? If you start the memory items withing 10 seconds you will not be wildly out of trim when doing the last part. It's called flying.

Control column............................................ .....Hold firmly

Autopilot (if engaged).......................................... .Disengage

Autothrottle (if engaged)........................................Di sengage

Control column and thrust levers..........................Control airplane
pitch attitude and airspeed

Main Electric
Stabilizer trim.............................................R educe control
column forces

If the runaway stops after the autopilot is disengaged:

Do not re-engage the autopilot or autothrottle.

----

If the runaway continues after the autopilot is disengaged:

STAB TRIM CUTOUT
switches (both)............................................ ....CUTOUT

If the runaway continues:
Stabilizer
trim wheel........................................Grasp and hold

That’s also a revised procedure that came out after the crashes. I don’t remember what it was before.

RJSAviator76 03-23-2022 08:12 AM

Until one has flown overseas, they'll have a difficult time understanding many things about these two crashes. It is a completely different world out there. Everything is based on autopilot. When doing a V1 cut, the very first item you do is turn the autopilot on at 400'. Before doing any checklist or memory items... autopilot first. When doing a visual approach, it requires to be programmed and both pilots will without fail be heads down trying to program it instead of turning off the auto-magic and flying the plane and uncoupled visual approach is practically an emergency maneuver. Autothrottle doesn't work or does something unexpected? They'll fly it right into a stick shaker and blame Boeing - see Asiana in SFO.

It's a different world out there. But careful, some of our progressive friends may call you some kind of an *ist or *phobe for even suggesting that.

Texasbound 03-23-2022 08:12 AM


Originally Posted by Hedley (Post 3393540)
That’s also a revised procedure that came out after the crashes. I don’t remember what it was before.

It was the same, just some of the steps were in notes, that you were expected to know and comply with. The FAA wanted them all made into steps.

ATC MEMES

CBreezy 03-23-2022 08:15 AM


Originally Posted by Texasbound (Post 3393529)
Wow, so after all that training you don't realize that using the manual wheel is at the end of the checklist? If you start the memory items withing 10 seconds you will not be wildly out of trim when doing the last part. It's called flying.

Control column............................................ .....Hold firmly

Autopilot (if engaged).......................................... .Disengage

Autothrottle (if engaged)........................................Di sengage

Control column and thrust levers..........................Control airplane
pitch attitude and airspeed

Main Electric
Stabilizer trim.............................................R educe control
column forces

If the runaway stops after the autopilot is disengaged:

Do not re-engage the autopilot or autothrottle.

----

If the runaway continues after the autopilot is disengaged:

STAB TRIM CUTOUT
switches (both)............................................ ....CUTOUT

If the runaway continues:
Stabilizer
trim wheel........................................Grasp and hold

Have you done it? The trim doesn't stop when you start the checklist and 10 seconds of running trim is going to cause significant stab forces to maintain straight and level. And by the way, prior to the accidents, the stab trim cutout occured after the first "if runaway continues." And there was no discussion of a technique on how to use the trim wheel or a discussion of unloading the flight controls as the ONLY method of manually trimming in a recovery from a runaway

WHACKMASTER 03-23-2022 08:19 AM


Originally Posted by CBreezy (Post 3393439)
The problem with the MCAS crashes was poor technique and late recognition from the pilot perspective. In the second crash, the crew actually hit the stab trim cutout switches. The problem was, the nose down forces were so great, they couldn't manually crank the trim. You actually have to unload the stab to be able to crank the trim wheel. This requires a kind a porpoising. And even then, it takes something like 40-50 turns to get it back to something manageable.

The second crew couldn't turn the trim wheel and the airplane was on the the verge of out of control. So they turned the electric trim back on.

To your last questions: yes it spins. Yes you can use trim to temporarily cut out the MCAS and yes you could theoretically grasp the wheel. Not sure how effective that would be but it is in the memory item. Why I think it takes so long to recognize is, the 737 actually has a system that trims the aircraft for you on departure so it's actually common to have that wheel spinning on its own as you are pulling flaps up and accelerating.

All correct, but it is not common to have the SPEED TRIM system trying to pull the yoke out of your hands.

I don’t get it. Is it not natural pilot nature to trim back against control forces that are pulling the yoke out of your hands in the nose down direction?

Texasbound 03-23-2022 08:20 AM


Originally Posted by CBreezy (Post 3393552)
Have you done it? The trim doesn't stop when you start the checklist and 10 seconds of running trim is going to cause significant stab forces to maintain straight and level. And by the way, prior to the accidents, the stab trim cutout occured after the first "if runaway continues." And there was no discussion of a technique on how to use the trim wheel or a discussion of unloading the flight controls as the ONLY method of manually trimming in a recovery from a runaway

Yes, I have done it... to include step 4 and 5. Step 5 has you retrim before turning the switches off. If you do it wrong you have to work harder, but the plane is controllable, unless you skipped step 4 as well.

There had not been a runaway stab in many years. SWA didn't even have it as a memory item anymore, but they were still expected to know it. The Stab Trim cutout did occur after the first "if runaway continues", but I bet you never read the notes. It still told you to trim before turning them off.

CBreezy 03-23-2022 08:26 AM


Originally Posted by WHACKMASTER (Post 3393555)
All correct, but it is not common to have the SPEED TRIM system trying to pull the yoke out of your hands.

I don’t get it. Is it not natural pilot nature to trim back against control forces that are pulling the yoke out of your hands in the nose down direction?

It doesn't pull out out of his hands, no. But by the time you recognize that it isn't doing what you want, it may be too late.

For example, I like to see that the airplane is doing. As you go from flaps down to flaps up and as you accelerate, constant trim changes occur. Sometimes I don't trim it out right away because I know after acceleration height, the trim required to go from flaps 5 to zero will be cancelled out somewhat by the trim required to go from 180-250. And I like to see what the speed trim is going to do. So no, I'm not always in perfect trim.

Texasbound 03-23-2022 08:28 AM


Originally Posted by DeltaboundRedux (Post 3393087)
“This airplane is designed by clowns, who are in turn supervised by monkeys"

That's really all you need to know about the Boeing corporate culture, and the employee's there knew it.

But I'm sure that's all fixed now, so fly with confidence.

If it's Boeing, it's going. Ready or not.

Well, the guy that said that is on trial this week. The people he was talking about are not. The FBI found no evidence of Management pressure.

The only clown he is worried about now if the one from the FAA that testified against him yesterday.

CBreezy 03-23-2022 08:29 AM


Originally Posted by Texasbound (Post 3393556)
Yes, I have done it... to include step 4 and 5. Step 5 has you retrim before turning the switches off. If you do it wrong you have to work harder, but the plane is controllable, unless you skipped step 4 as well.

There had not been a runaway stab in many years. SWA didn't even have it as a memory item anymore, but they were still expected to know it. The Stab Trim cutout did occur after the first "if runaway continues", but I bet you never read the notes. It still told you to trim before turning them off.

There are no notes in the memory items to trim out the runaway trim condition.


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