Alaska Airlines flight forced to make an emergency landing... 82

[Alistair_Heaton]

I wouldn't call it an apology.... but its better than blaming the pilots which was what they have previously done for pretty much everything.

(To be fair most of the time it is the pilots..)

https://edition.cnn.com/2024/01/09/business/boeing-safety-meeting-737-max-factory/index.html

 

[zeusfaber]

What will people with "severe intellectual disabilities" contribute to the FAA?

Logistics for the entire UK Armed Forces used to be run out of a decaying abandoned fever hospital overlooking the city of Bath. One of its few redeeming features was the tea and bun trolley that meandered aimlessly around the site, operated by an unlikely looking pair - one physically capable of pushing the trolley around and the other intellectually capable of handling cash.

 

[Alistair_Heaton]

I was told that the one pushing the trolley was a decorated Military Police undercover... The other dealing with the cash was NAAFI.

 

[dik]

There's one huge difference. With engineering decisions, I think I'm reasonably good. I have reasonable time to develop these. A pilot may not have that luxury; his decisions may be 'split second'.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Alistair_Heaton]

There are very few infrequent situations a snap decision is required. Fire and smoke, rejected takeoffs in the sim and the last 10ft landing in pretty bad weather in my experience and that only happened once last year.

 

[dik]

Thanks Alistair... didn't know that... thought the decision process was a lot faster; I suspect under some circumstances it may require prompt action.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Alistair_Heaton]

Yes when your close to the ground or on fire.

But most of the time you have time for running a decision making algorithm.

Which is why the MACAS was so shocking for the majority. 5 seconds to spot it, analysis it, then action. Any longer and control forces were to much.

When the FAA test pilots went into the SIM pre warned it was going to happen the majority of them messed the first one up and couldn't recover.

There were only a couple of max Sims at the time world wide with the ability to simulate it.

And the is this landing not going to work decision isn't really a high level data processing. It's more of a picture isn't right let's get the hell out of here and do it again.

 

[3DDave]

5 seconds? That is as incorrect as possible. After 9 seconds the controls moved to put about 20 pounds on the controls and then would do nothing unless the pilot altered the trim.

It required at least 30 cumulative seconds of mistrim operation to become too much to handle and at no time did pilot electric trim become disabled.

The sim was - what if at 450 knots and full down trim could the pilots recover.

No one recalls that the first flight MCAS was seen as annoying before the pilots finally remembered the trim disable switch - 20 or so separate operations of MCAS, all fully retrimmed. Not only were they handling the issue, they even tried an experiment to turn the trim back on - MCAS responded to their trim input and they shut it back off.

The second flight - same result from the captain. No loss of control until his first officer thought the goal was to stop the trim wheels from moving instead of returning the plane to trim.

The third flight - they had plenty of time and made every wrong decision from the first stall warning. To know how bad this was - there were no sims in the world that could manage MCAS because no sim in the world had a way to falsify the AOA data but remain valid. Ethiopia had at least one MAX sim and would have known they could not train that scenario because the sim didn't support it; they didn't call Boeing to ask for a simulator software update, but put an inexperienced First Officer into the cockpit anyway.

 

[LionelHutz]

MCAS was pretty much beaten to death already. There is lots of blame to go around and Boeing certainly has their share.

Neither of the last 2 posts are correct about the details either.

 

[3DDave]

Show the errors based on the FDR data.

 

[waross]

5 seconds? That is as incorrect as possible. After 9 seconds the controls moved to put about 20 pounds on the controls

Respectfully, it may have been a good part of that 9 seconds or even a little more before the pilots started the 5 second "recognition" time.
That's strange the controls are getting heavy, to the controls are too heavy to manage.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[waross]

What is DEI?
I don't mean the textbook definition, but the real world application.
If the short list has only qualified candidates, then DEI may be acceptable and certainly can not be blamed for poor performance.
But, when some MBA thinks that DEI driven PR will improve the bottom line, and sets quotas, then middle managers have a choice:
Fudge the qualifications to make the quota,
or
Do an honest an professional job of screening candidates for the short list and watch the cheaters get the bonuses.
Not DEI but the implementation of DEI.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[3DDave]

As noted before - the controls become too heavy to manage after nearly 30 seconds of uncountered trim. The first crew and second captain managed to 100% undo the trim increment. The second F/O didn't offset any trim increment. The crew of ET-302 failed to counter the majority of the trim increment, but compounded the problem by failing to pull back the throttle as part of the required stall warning response.

 

[3DDave]

DEI needs a separate thread.

 

[Alistair_Heaton]

Much like Sullys situation which was later proved in the sim about the ditch or try to return to the airport, Startle effect of anything usual happening has to be removed from the time line.

 

[Alistair_Heaton]

oh btw in this one.

The previous events with the pressure controller throwing an error. Apparently the other two controllers didn't throw an error. If it had been uncontrollable cabin pressure because the door was off its seal then all 3 would have failed so I can understand why the techs went down a sensor failure route.

Apart from anything else a visual inspection outside shows up if a door isn't where it should be.

 

[1503-44]

The one common thing I've personally seen with "sensor failures" is that its never sensor failure.
The MTTF of pressure sensors is several hundred years. Not to say they don't happen, but it can make even one PI error potentially quite serious. If 3 are not actually monitoring pressure of the exact same point, ie different locations in the same containment envelop, there will be a restriction or opening in the envelop. Voting only works well if all are measuring pressure at the exact same place. The Boston gas explosion occured because the PI became disconnected.

 

[Alistair_Heaton]

We get a fair few of them on older types.

Mainly because they don't change them due certification cost.

Bit like AoA sensor on the max.

 

[1503-44]

I should clarify, its pressure sensors I mean specifically.

Yes, they happen, but instrument error shouldn't be the first thing the tech guys think about and its like always #1. I don't know the MCs, but pressure sensors usually work. The computer reading them always bums out first. Big pet peve. Home appliances only run 2 yrs now without a microprocessor replacement. Before I could get 10 to 15yrs of trouble free (maybe not at max efficiency) ops out of them. Now it's $250 every 2 to 3 yrs. and its 2/3 to full cost of item to replace the micro.

DEI is just the new hip name for the old "affirmative action". Nothing's really changed there since 1978, except the people complaining about it. All the big problems still originate at the top and they keep blaming it on the bottom. I liked SBF's novel reason,"My girlfriend and my mom did it". At least that was original.

 

[LittleInch]

Three pressure controllers on the Max?

Thought they worked 1oo2 for most bits of control gear. Not airbus 2oo3.

Door sealing errors are also rather rare I would think. Those spare doors have been around for a long time since the 737-900 I think so many hours of service and they haven't fallen off before...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.