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Alaska Airlines flight forced to make an emergency landing (Part II)... 26

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They are not all retired. Calhoun was on the board when all the decisions were made. And you misread me entirely. I'm not at all gleeful about Boeing's troubles. I'm totally disgusted. It was a pride of America and now its sh!t and its not alone. Who else here has a Boeing cap? I'm embarrased to ware it, but still haven't burnt it. What the hell still works in the good ole USA anyway. But I have hope. The sooner their current management packs up and gets the hell out, the better. Lord only knows why they have to EOY. Maybe it looks too bad, if it can look any worse, if they take the redeye back to wherever it was they came from. And, if you want to fly, best not build rocks and paint them silver.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
 
No comments on the new CEO? A BA in accounting and leader of the Employee Resource Group, a diversity and equity program...
 
The bad decisions were about the AoA system and the SMYD (stall management, yaw damper) that reported inaccurate AoA readings and made the false stall warning. That was decided multiple decades ago and approved by the FAA and all using airlines. The all agreed that pilots depending on that potentially false information was acceptable.
 
70 years ago conceptually. Do we still build new cars to the same standards as 60 years ago?

Can a 21 year old today jump into a 1970's car and be expected to deal with it as his great grandad could?.
 
tug said:
No comments on the new CEO?
Click to expand...

Its problems are base level technical. She is as much use as an engineer dealing with human factors and human physiology reaction to over load.

But she is the CEO of Boeing Commercial Airplanes, a DIVISION of Boeing. Still think though they should go back to technical leadership of all technical divisions.
 
Jumping into any plane - obviously not. But, right or wrong, they need to be capable of flying that plane type or else they shouldn't be in the cockpit.

The bad on Boeings part is the decision to shelf the development of a new plane to replace the 737 back around 2010.
 
its capacity and flexibility in a pilot. Both of which require exposure to similar "shit"

And I fully agree "they need to be capable of flying that plane type"

But if the training requirements/experience base is vastly more than other types its dead...

 
The training was the existing stabilizer runaway training. Exactly the same. If anyone is hurt that no one explained what "runaway" meant, they still haven't. Deal with it.

As mentioned - no one complained there wasn't "safety wire short circuit with trim switch installed upside down training." That was also a case where the trim failure was intermittent, but that was because the pilot using the trim switch that was placarded out and the EICAS reported a problem, was doing so intermittently, yet it appeared to that pilot that the stabilizer was out of control.

What every pilot needs is startle-goat training. And the FCOM needs to be written in "Explain like I'm five-years old" formatting.
 
Some of us they do try and do startled goat training.

The fo it's done by killing the captain. And making them deal with something single crew.

And yes the manuals need to be pretty simply worded and written in an international basic English method.
 
I think a skilled instructor should give us engineers a write-up of how "stabilizer runaway" should be done.
 
more than half the issue is realising what's going on.

oh and been reading about the ejet trim issue.

That does appear to be a mess by the certification authorities.

Both Jetstream and Q400 used trim tabs not whole tail elevator driven pitch changes for trimming. I never had one flying either and thinking about it I can only remember twice doing trim runaway in the sim on both. And the forces were low enough you could just manually fly it and manually trim it. And no reports of it occurring on either. The q400 it used to beep at you if the motor was running more than a couple of seconds.

I really have zero clue about the 737 QRH. I know its an absolute brick of a book. The trim runaway memory item on the MAX is the same as the one issued in 1967 on the original 737.

Sitting on the jump seats and an occasional job interview sim there is a hellava lot going on constantly in a 737 on departure all the way up to cruise.

A220 not a lot happens even flying it manually, gear up. 400ft the autopilot can go in. If not you just accelerate, a blue bug is on your speed tape showing you the speed the plane is trimmed to. You just adjust it as you go faster, clean up the flaps and then climb away. We don't have a manual trim wheel.

If the computers are out you don't get a blue bug, but the stick is neutral when at trim speed and you need constant input if not. But as everything is powered surfaces wise there is no requirement to brute force anything. The only force is the spring on the stick.



 
"The training was the existing stabilizer runaway training." That was one of the key issues - the runaway stabiliser in previous versions of the 737 could be halted by pulling back on the control column to stop the stabiliser movement. Also you could disable the trim system commands separately from the trim switches. In MCAS it didn't work like that and nowhere in the emergency AD does it tell you that regardless of what you do with the control column, the trim keeps moving unless you hit the cut out switches. It doesn't tell the pilots that moving the trim buttons is the ONLY way to stop the system moving the trim.

For classic runaway trim the trim would start to move as soon as you released pressure on the control column. MCAs worked differently. It commanded nose down trim for up to 10 seconds. That's a hell of along time while the pilots are suddenly confronted with an airplane heading for the brown stuff and desperately pulling back on the control column. Nor does it say that even if you trim it back using the trim buttons and get level flight, you think it's all going well and 5 seconds later it nose dives again. Again not written into the emergency AD.

All this was designed to happen.

The upside down switch wasn't - that is poor QA and poor CRM to somehow use something marked an inoperative. Massively different.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
"That was one of the key issues - the runaway stabiliser in previous versions of the 737 could be halted by pulling back on the control column to stop the stabiliser movement."

That was step 1. If that failed, as it did, there was step 2. No one seems to remember there was step 2.

"For classic runaway trim the trim would start to move as soon as you released pressure on the control column."

Since pulling the column did not stop the movement, then using "start to move as you release pressure" has nothing to do with diagnosing the problem, but the requirement is that if it did not stop one was to trim to neutral and use the CUTOUT switch.

The guy with 154 hours on type was not so ingrained as to have been taken by surprise. The captain certainly had not had so many stabilizer runaway events as to only recall step 1.

"All this was designed to happen."

No, it wasn't. It was never "designed" to operate with an invalid AoA sensor that was given the OK signal by the SMYD. This is called "oversight" or "mistake."

The`10 second stop was a fail-safe. It was assumed that the pilot would return the plane to a lower AoA and keep it there. 5 seconds is following the pilot input to the trim system.

"The upside down switch wasn't - that is poor QA and poor CRM to somehow use something marked an inoperative. Massively different."

Continuing to confuse cause with symptom and response. It doesn't matter what the cause was; deal with the symptom. The symptom was stabilizer trim changing and those calling for some specific cause to be addressed miss the point that the cause is immaterial to the pilot response. Want "MCAS training"? Require training for every possible cause; maintenance f'up is a pretty common. By-design the switch was allowed to be installed upside down. By design the maintenance procedure did not use the related trim cutout.
 
Doesn't the DOT do inspections of airplanes? Don't the mechanics do inspections? So why would this be a Boeing issue and no one else?
Where is the head of the DOT on the values there inspectors bring?
 
Crankie where i am they can do but tend not to because they don't have anyone licensed to take panels off and a few other things. You need approval via the airlines QA system to document things so its not just the case of going in and having a look and leaving it how you found it. It needs to be signed off that it is and the DOT don't have those approvals.

Yes technicians/mechanics do inspections, there is daily checks, weekly checks etc etc all documented by approved individuals.

The findings are passed to the regulators via the QA system, anything major and a mandatory occurrence report needs to be generated. And to the OEM's but that side of things I have no clue about.

Aircraft these days speak to the OEM's digitally. And its not unheard of for phone call from Canada for us on the A220 to the continuing airworthiness maint officer (CAMO) to occur and the plane is grounded next time it comes back to base.

 
I don't think they are having anything special with the fleet size that they have.

Its just every little event is in the media especially if its a Boeing.

It does seem to happen in groups of stuff in most company's you can go for weeks with zero Aircraft on Ground and then there is three or four of them go on the same day.

And I know this sounds very unscientific and none engineering.... I tell ya full moon is a time of incidents both pax related and equipment.

 
Is it worth having another thread on general issues?

Seems things are moving away from 737 singular issues.


Oh and the human performance characteristics from the 50's which have been used by Boeing will be officially out the door in 6-12 months apparently. According to EASA real pilot types that are guinea pigs forming the new ones. They also have groups from the other cultural groups and world wide training areas including FAA.

30 seconds recognition seems to be banded about min. With 60 seconds the norm without pilot input to rectify. There are discussions about pilot lockouts on some features. And also the use of AI
 
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