Had to chuckle at this: "If you have made it this far, I first of all commend your patience, and/or your nerdiness."
A thoroughly enjoyable write-up this was.
A Matter of Millimeters: The story of Qantas flight 32
271–280 of 307 posts
Re: A Matter of Millimeters: The story of Qantas flight 32
#27230 years ago I was in an emergency landing due to engine failure situation (flight attendants take away your shoes, practice crash position, rearrange the passengers etc) and the thing that stuck out the most for me was that everybody did as they were told. No self righteous people; it was clear to everyone why there are flight attendants aboard and that they were key to your survival. The evacuation was orderly, tho…
People evacuate with their luggage because in times of high stress, we fall back on habit. What do we do when it's time to leave an aircraft? We make sure we have all our belongings with us! That's just one reason why it's important to listen to the safety briefing, even if you've heard it before. The repeated drill helps us to remember what to do, even when there's added stress.
I don't really think the phenomenon is anything other than people selfishly wanting their belongings to be saved over another passenger's life.
Re: A Matter of Millimeters: The story of Qantas flight 32
#273Many things failed, at least:
(1) failure to identify safety-critical parts for review
(2) failure in design drawings made without regard for fabrication
(3) failure to make reference to original design goals when altering part designs
(4) bad machining plan altering work-holding during the machining
(5) failure to inspect finished parts
Re: A Matter of Millimeters: The story of Qantas flight 32
#274Earlier quoted context omitted.
An example of zipper failure in the Airbus incident is when a wire bundle gets cut, all the functions of all the wires in that bundle are lost. Having two or more smaller bundles physically separated would greatly reduce that risk. Certainly, having the primary and the backup system in the same bundle is a bad idea. On the 757, one set of control cables runs under the floor. The backup set runs in the ceiling.
It’s the same on Airbus aircraft, I can tell you from experience.
I thought Airbus was fly-by-wire, not cables?
Re: A Matter of Millimeters: The story of Qantas flight 32
#275Earlier quoted context omitted.
At this point the secret sauce is that the EAA isn’t tolerating the same degree of certification fucking and laxity from airbus, and that they generally seem to have their act together. Like what’s the secret sauce of nvidia vs radeon or AMD vs intel? Reliable execution, seemingly - and this is an environment where failures are supposed to be contained to very specific rates at given levels of severity. The FAA has g…
It's actually safer for new airplane types to have flying characteristics like the previous types. There have been many accidents where a situation happened and the pilot did the right thing for the previous airplane he flew, but was the wrong thing for the one he was currently flying. Most of what was written about the MAX crashes in the mass media is utter garbage and misinformation. No surprise there, as journalis…
Everything I wrote is true. The LA crew restored normal trim 25 times, but never thought to turn off the stab trim system. The trim cutoff switch is right there on the center console within easy reach for just that purpose.
The EA crew oversped the airplane (you can hear the overspeed warning horn on the CVR) and did nothing to correct it. This made things worse. They were also given an Emergency Airworthiness Directive which said to restore normal trim switches, then turn off the trim system. They did not.
That's it.
I'd say half the fault was Boeing's, the other half the flight crews'.
The MCAS is not a bad concept, note that MCAS is still there in the MAX.
Pilots are a brotherhood, and they don't care to criticize other pilots in public. But they will in private.
Re: A Matter of Millimeters: The story of Qantas flight 32
#276The part out of tolerance could have been caught by comparing it to a master part within tolerance?
Laserscan it or capacitor probe measure it and encounters the lack of material.
In car part companies there is usually a qm-lab drawing samples from production. Does airplane turbine production not have this step?
Re: A Matter of Millimeters: The story of Qantas flight 32
#277Earlier quoted context omitted.
The author is positive because of all the safety layers that existed and staid intact, despite how flawed humans and companies are. The culture of looking at previous accidents like the UA232, where they lost ann engine and ALL controls with it, meant the A380 control system was engineered to take even more damage and it worked. I do agree though it did not spend enough effort focusing on the areas to improve: - A co…
> - A fault management system that only shows you 1 or 2 at a time when you have 40. As long as the system prioritizes the warnings/cautions with the most pressing ones shown first, this is a very good thing. In a high-stress situation, you don't want the pilots to have to deal with figuring out which of the 40 warnings need to be taken care of first.
…none of which did happen. Checklists are not made for “prioritization”. Checklists are not made for “high-stress situations”. They simply had to do that because that was the intended way to diagnose a complex black box. If you don't have an hour to hang in the air, bad luck. There is an obvious unusable model of operation, and you praise it for being good… because someone said it's good?
Re: A Matter of Millimeters: The story of Qantas flight 32
#278The article is complex and well written, but I am a bit perplexed by the victorious tone and never-ending praise of safety. It resembles a sales pitch a bit too much, even though no one is selling anything. Maybe it's unintentional, and being around salesmen just does that to people. If you are like me, you've probably said “hmm…” to yourself multiple times when certain things were mentioned, because those were thing…
I've read dozens of Admiral Cloudberg articles, and when you do so you notice a pattern: in old aviation crashes, a single error or a single part failure usually took down a plane with tens of dead bodies. Also the story of how and why the sterile flight deck started in response to some crashes where the pilots were distracted talking. In modern aviation accidents, it seems very unlikely. Even with an engine explodin…
That's the problem. Even if there were victims, one could've written the exact same article about “flying even safer”.
Re: A Matter of Millimeters: The story of Qantas flight 32
#279The article is complex and well written, but I am a bit perplexed by the victorious tone and never-ending praise of safety. It resembles a sales pitch a bit too much, even though no one is selling anything. Maybe it's unintentional, and being around salesmen just does that to people. If you are like me, you've probably said “hmm…” to yourself multiple times when certain things were mentioned, because those were thing…
> the computer keeping the broken engine running That’s on purpose, you don’t want an automation decide such a drastic move as shutting down an engine. That’s the pilot’s decision. > absence of any physical kill switch to stop the engine There is, you shut down the fuel flow with a valve. But that “kill switch” was damaged. > An hour being generously available to go through ALL the checklists to clear the notificatio…
I'm not an idiot (citation needed). I can see that a storm unplugging some imaginary tiny heartbeat cable, which in turn shuts down all the engines instantly, is not how planes should operate. What I don't understand is the approach to defend status quo, and pretend that “randomness is now conquered”.
It seems to me that fixing one complex problem creates 10 other complex problems. They can be rare, but it's ignorant to shift focus from them.
Re: A Matter of Millimeters: The story of Qantas flight 32
#280Earlier quoted context omitted.
> - A fault management system that only shows you 1 or 2 at a time when you have 40. As long as the system prioritizes the warnings/cautions with the most pressing ones shown first, this is a very good thing. In a high-stress situation, you don't want the pilots to have to deal with figuring out which of the 40 warnings need to be taken care of first.
…none of which did happen. Checklists are not made for “prioritization”. Checklists are not made for “high-stress situations”. They simply had to do that because that was the intended way to diagnose a complex black box. If you don't have an hour to hang in the air, bad luck. There is an obvious unusable model of operation, and you praise it for being good… because someone said it's good?
We're not talking about checklists. We're talking about the ECAM warnings/cautions/advisories display. It's a well known fact that overwhelming human operators with large amounts of information all at once is a bad thing -- even just in aviation, there are numerous examples. That's why there's a 'clean cockpit' rule that the FAA enforces; Distracting pilots with either useless, or extraneous and not immediately actionable information one average, causes worse outcomes. Checklists largely come into play once you start acting on the ECAM warnings.
Also, as the article says, the pilots did their job following the aviate, navigate, communicate mantra. They first made sure they had the appropriate time to follow the checklists, and only then did they proceed to follow them.
There's over 100 years of aviation experience backing many of these procedures and approaches to dealing with problems. Many are hard-won with literal blood and lives.