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Preliminary report into Air India crash released

bbc.co.uk

571–580 of 924 posts

Re: Preliminary report into Air India crash released

#571

It's safe to state these fuel cutoff switches aren't to be touched in-flight unless the word 'fire' is said beforehand. Even then, you only perform fuel cutoff for the flaming engine. If the copilot was busy with takeoff, there is exactly one other person in the entire world that could have flipped both switches. We may never know which one flipped them back.

There is a visual cue in the case of fire so the pilot won't turn off the wrong engine.

Re: Preliminary report into Air India crash released

#572

Earlier quoted context omitted.

Consider a case where the engine starts to violently vibrate. This can tear the structure apart. Delaying shutting off the engine can be catastrophic. It's very hard to solve one problem without creating another. At some point, you just gotta trust the pilot.

If you read through the boeing procedures, if an engine fails just after take off you delay cutting throttle or hitting the cutoff until you have positive climb and pass a certain altitude. Specifically because a mistake here would be so incredibly catastrophic. The following number of steps and verbal cross checks for then shutting down the engine are quite daunting. Not something applicable here, but still interest…

That’s absolutely applicable here. It means that an engine cutoff shouldn’t be allowed at all during certain parts of flight. It’s not crazy to think that a design fix would be to prevent those engagements during certain parts of takeoff (a certain window). It’s fly by wire anyway so it could presumably be done programmatically.

MCAS was basically made to prevent user input that would send the plane into a dangerous angle. The computer overrode the inputs. So there’s precedent for something like it.

Re: Preliminary report into Air India crash released

#573

Three things:- 1) Pilot clearly said I didn't do it. 2) Report talks about the second switch being turned off in a second. 3) Known advisory on switches getting flipped. If you see these three together, it becomes easy to deduce that based on point 2, switch was not human induced as the actions required take more than a second. Next the third point, advisory was for this exact scenario which played out, though rare b…

The advisory was for the lock being disengaged meaning you would still need to manually move it. it wasn't for being moved by factors such as vibrations also If it was from vibration how would a crash impact not move them back to cut off?

Re: Preliminary report into Air India crash released

#574
Most importantly it's extremely problematic that BBC is pushing the pilot error angle subtly! This is a preliminary report! No news organization should spread opinion pieces based on this. Somehow it feels like Boeing paid BBC to shift the narrative.

We should all wait for the final report. Pilot error or Machine fault, either way it's a huge tragedy.

Re: Preliminary report into Air India crash released

#575

I recall something similar to this happened in the USA in 2023. An off-duty pilot in the cockpit tried to pull that fuel shut-off handle (edit: I'm informed it's a different fuel shut-off mechanism), but was overpowered by the other two: > "Both pilots then saw Emerson grab on to the red fire handles, also known as the “T-handles,” which are used to extinguish engine fires and shut off all fuel to the engines, potent…

That's not the same one, that's the big red FIRE ones on the overhead panel. They're not reversible and are under a plastic cover. As far as I know these ones are. They're also used to just switch them off at the end of a flight which can of course be reversed. But I guess in this case there wasn't enough time. They only had 30 seconds.

Re: Preliminary report into Air India crash released

#576
post #396

Earlier quoted context omitted.

> Did you ever always push the right buttons every time? A whole world full of 787’s is pushing the right buttons every single day. If we’re talking about accidentally pressing buttons it seems we’d have seen incidents before.

> If we’re talking about accidentally pressing buttons it seems we’d have seen incidents before. Well, of course I talk about an accidental touch of the wrong buttons. Flying is very safe, but at the same time, you will never know how many near misses happen daily that don't become accidents.

Actually we do https://en.wikipedia.org/wiki/List_of_US_aircraft_near-miss_...

Re: Preliminary report into Air India crash released

#577

Earlier quoted context omitted.

Is there a video feed of the cockpit inside the black box? If not there should be one as even my simple home wifi camera can record hours of hd video on the small sd card. And If there is, wouldn't that help to instantly identify such things?

No neither black box stores video. One stores audio on flash memory and the other stores flight details, sensors etc. I don’t think video is a bad idea. I assume there is a reason why it wasn’t done. Data wise black boxes actually store very little data (maybe a 100mbs), I don’t know if that is due to how old they are, or the requirements of withstanding extremes.

In the US, the NTSB has been recommending it for over 20 years. The pilot unions have been blocking it, due to privacy and other things.

I'm not in aviation. But my between-the-lines straightforward reading is that unions see it as something with downsides (legal liability) but not much upside. It could be that there are a million tiny regulations that are known by everyone to be nonsensical, perhaps contradictory or just not in line with reality and it's basically impossible to be impeccably perfect if HD high fps video observation is done on them 24/7. Think about your own job and your boss's job or your home renovation work etc.

Theoretically they could say, ok, but the footage can only be used in case the plane crashes or something serious happens. Can't use it to detect minor deviations in the tiniest details. But we know that once the camera is there, there will be a push to scrutinize it all the time for everything. Next time there will be AI monitoring systems that check for alertness. Next time it will be checking for "psychological issues". Next time they will record and store it all and then when something happens, they will in hindsight point out some moment and sue the airline for not detecting that psychological cue and ban the pilot. It's a mess. If there's no footage, there's no such mess.

The truth is, you can't bring down the danger from human factors to absolute zero. It's exceedingly rare to have sabotage. In every human interaction, this can happen. The answer cannot be 24/7 full-blown totalitarian surveillance state on everyone. You'd have to prove that the danger from pilot is bigger than from any other occupation group. Should we also put bodycam on all medical doctors and record all surgeries and all interactions? It would help with malpractice cases. How about all teachers in school? To prevent child abuse. Etc. Etc.

Regulation is always in balance and in context of evidence possibilities and jurisprudence "reasonableness". If the interpretation is always to the letter and there is perfect surveillance, you need to adjust the rules to be actually realistic. If observation is hard and courts use common sense, rules can be more strict and stupid because "it looks good on paper".

You also have to think about potential abuses of footage. It would be an avenue for aircraft manufacturers, airlines, FAA, etc to push more blame on the pilots, because their side becomes more provable but the manufacturing side is not as much. You could then mandate camera video evidence for every maintenance task like with door plugs.

I wonder how the introduction of police body cam footage changed regulations of how police has to act. Along the lines of "hm, stuff on this footage is technically illegal but is clearly necessary, let's update the rules".

Re: Preliminary report into Air India crash released

#578

Earlier quoted context omitted.

No neither black box stores video. One stores audio on flash memory and the other stores flight details, sensors etc. I don’t think video is a bad idea. I assume there is a reason why it wasn’t done. Data wise black boxes actually store very little data (maybe a 100mbs), I don’t know if that is due to how old they are, or the requirements of withstanding extremes.

This isn’t true. This was a 787. It does not use a separate recorder for voice and data (CVR, FDR). (Most media outlets also got this wrong and were slow to make corrections. ) Rather, it uses a EAFR (Enhanced airborne flight recorder) which basically combines the functions. They’re also more advanced than older systems and can record for longer. The 787 has two of them - the forward one has its own power supply too.…

That's really interesting. From reading air crash reports there's a lot of times I've seen."Nothing is known about the last 30 seconds because the damage broke the connection to the flight recorders in the tail"

Re: Preliminary report into Air India crash released

#579
post #72

it makes sense to me that the pilot who said "I did not do it" actually did do it without realizing it, was supposed to be putting the landing gear up when he committed a muscle memory mistake. it happened around the time the landing gear should be up, and this explanation matches what was said in the cockpit, and the fact that the landing gear wasn't retracted. I think this idea was even floated initially by the you…

The landing gear lever is rather prominently featured in the 787 in a panel central to the cockpit layout so that either pilot can easily reach it. For decades and across many manufacturers, the landing gear lever has traditionally featured a knob that deliberately resembles an airplane wheel. It's very hard to mistake it for anything else. It's actuated by simply moving it up or down. The fuel control switches are b…

> It's very hard to mistake it for anything else. It's actuated by simply moving it up or down.

On some aircraft types you also have to pull it towards you before moving it to avoid hitting it by mistake.

But I agree it's very unlikely to be a muscle memory mistake.

Re: Preliminary report into Air India crash released

#580
post #467

I just want to call out that, whatever the facts of this case, pilot heroism is way more common than pilot murder. This is off the top of my head, so don't quote me on the precise details, I'm probably misremembering some things. But a few of my favorite examples: - British Airways 5390: An incorrect repair causes the windshield of a plane to be blown out mid flight. A pilot is nearly sucked out. The head flight atte…

Here's another one: Air Canada 143 - Pilot calculated incorrect fuel due to metric/imperial unit mixup, and ran out of fuel midair. - Said pilot performed an impossible glider-sideslip maneuver to rapidly bleed airspeed just-in-time for an emergency landing at an abandoned airfield, having to completely rely on eyeballing the approach. - No fatalties or serious injuries. https://www.youtube.com/watch?v=jVvt7hP5a-0

It was a series of events and failures rather than simply “pilot calculated incorrect”. And it was a bit more nuanced than metric/imperial conversion.

Via wiki (but accident section is more detailed):

“ The accident was caused by a series of issues, starting with a failed fuel-quantity indicator sensor (FQIS). These had high failure rates in the 767, and the only available replacement was also nonfunctional. The problem was logged, but later, the maintenance crew misunderstood the problem and turned off the backup FQIS. This required the volume of fuel to be manually measured using a dripstick. The navigational computer required the fuel to be entered in kilograms; however, an incorrect conversion from volume to mass was applied, which led the pilots and ground crew to agree that it was carrying enough fuel for the remaining trip. ”

https://en.m.wikipedia.org/wiki/Gimli_Glider

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