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Preliminary report into Air India crash released

bbc.co.uk

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Re: Preliminary report into Air India crash released

#381

Post by 0_-_0 »

sitharus wrote: post #351
bombcar wrote: post #92

Earlier quoted context omitted.

It's interesting to try to imagine a device that would prevent that, without causing more issues. My preliminary idea is a "fuel bladder" for take-off that inflates with enough fuel to get the plane to a recoverable altitude, maybe a few thousand feet?

Or you simply interlock the engine cutoff with the thrust lever position, any position other than idle prevents shutdown. This all goes through the flight computers already. If there’s a fire or similar problem the fire handles will cut off fuel without the normal shutdown procedure, but the normal switches only need to be used at idle thrust. I wonder if Airbus has this logic, since their philosophy is to override t…

According to AI, Airbus places these switches on the overhead panel, so that alone would make it harder to inadvertently move them. Apparently, Airbus "protections do not extend to mechanical or FADEC‑controlled systems like the engine‑fuel shutoff valves. If you deliberately pull and flip the ENG MASTER lever to OFF, the FADEC will immediately close the LP and HP fuel valves and the engine will flame out. If you then return the lever to RUN (and you meet relight conditions), it will automatically relight."

Re: Preliminary report into Air India crash released

#382

Post by i_have_to_speak »

decimalenough wrote: post #11

> The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off. So the fuel supply was cut off intentionally. The swi…

[flagged]

Re: Preliminary report into Air India crash released

#383

Post by toast0 »

stephen_g wrote: post #214
bombcar wrote: post #154

Earlier quoted context omitted.

The idea would be something that is ONLY operational after V₁ and until some safe height. Or maybe a design that prevents both switches being off (flip flop?) for X minutes after wheel weight is removed? Again, it’s probably pointless but it’s an interesting thought exercise. Suicidal pilots are apparently more common than we’d want.

It’s a pointless exercise though - if one of the pilots wants to crash the plane, there’s almost nothing that can possibly be done. Only if someone can physically restrain them and remove them from the controls. There’s always going to be many ways they could crash the plane, such a feature wouldn’t help. The pilots are the only people you can’t avoid fully trusting on the plane.

It's only pointless if we assume crashing was the intended result of the pilot. If the switches failed, or the pilot activated the switches by mistake, it's worth considering options for handling the inputs.

There's a balance of accidents to be found, I think. There are likely cases where fuel does need to be cut off to both engines, and preventing that would lead to accidents that might have been recoverable. This case shows that cutting off fuel to both engines during takeoff is likely unrecoverable. There have been cases where fuel is cutoff to the wrong engine, leading to accidents. Status quo might be the right answer, too.

Re: Preliminary report into Air India crash released

#384

Post by cjbprime »

vishnugupta wrote: post #333
cjbprime wrote: post #156

Earlier quoted context omitted.

> There is no possible way to confuse these two actions. This is obviously an overstatement. Any two regularly performed actions can be confused. Sometimes (when tired or distracted) I've walked into my bathroom intending to shave, but mistakenly brushed my teeth and left. My toothbrush and razor are not similar in function or placement.

If I were to apply OPs assertion to your actions it’s like brushing your teeth with razor. I guess that’s what they meant.

Not really, though. They're both (retracting the gear, and cutting off fuel) just toggle switches, as far as your brain's conscious mechanisms go. Doing them both on every flight dulls the part of your brain that cares about how they feel different to perform.

(I'm not strongly arguing against the murder scenario, just against the idea that it's impossible for it to be the confusion scenario.)

Re: Preliminary report into Air India crash released

#385

Post by rurban »

sillysaurusx wrote: post #50
lazystar wrote: post #17

Earlier quoted context omitted.

https://ad.easa.europa.eu/ad/NM-18-33 well hold your horses there... from the FAA in their 2019 report linked above: > The Boeing Company (Boeing) received reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The fuel control switches (or engine start switches) are installed on the control stand in the flight deck and used by the pilot to sup…

https://www.youtube.com/live/SE0BetkXsLg?si=LPss_su3PVTAqGCO Both of these extremely-experienced pilots say that there was near zero chance that the fuel switches were unintentionally moved. They were switched off within one second of each other, which rules out most failure scenarios. If it was an issue with the switches, we also would have seen an air worthiness directive being issued. But they didn’t, because this…

Only the captain was extremely experienced, the FO was a rookie. He wouldn't have had enough hours for an European airline

Re: Preliminary report into Air India crash released

#386

Post by t0mas88 »

tzs wrote: post #346
maxbond wrote: post #295

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…

> British Airways 5390: An incorrect repair causes the windshield of a plane to be blown out mid flight. A pilot is nearly sucked out. This one is a good illustration of how better design can help prevent accidents or make them less severe. The error the maintenance people made was that when they replaced the window and the 90 screws that hold it on 84 of the screws they used were were 0.66 mm smaller in diameter tha…

Aviation is full of those design choices. Similar to how a multi-engine propeller plane will use oil pressure to keep the props in the flying angle, which means that when oil pressure is lost (catastrophic engine failure) it will feather giving the other engine the best chances of keeping the plane flying with the least amount of drag. While on a single-engine plane it's installed exactly opposite, in case of oil pressure loss the prop goes to fine pitch giving you the best hope of creating some trust in case the engine may still be working.

Most of these things were figured out over 100 years of carefully analysing accidents and near accidents to continuously improve safety.

Re: Preliminary report into Air India crash released

#388

Post by burnt-resistor »

imoverclocked wrote: post #358
burnt-resistor wrote: post #297

Earlier quoted context omitted.

Yep. Fan blade off, shroud separation, HP disc separation, compressor stall, FOD ingestion/bird strike, EGT rise, oil system issues. Very unlikely events but still possible events that need a prepared response to and capabilities to manage the aircraft. The presumption is that the crew is trained, diligent, disciplined, and concerned with survival. Without that, aircraft would need to be unmanned and flown by AI lack…

I'm not sure you want a creative AI flying a plane anyway.

I don't want AI planes either, but the alternative of unmanned is ground-based drone operators who lack the survival interests of being on the planes. As such, I want non-AI flown planes with sane, stable, rested, practiced, experienced, sober pilots on the plane that isn't overly complicated and is reliable.

Re: Preliminary report into Air India crash released

#389

Post by anal_reactor »

notpushkin wrote: post #301
maxbond wrote: post #295

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…

Mentour Pilot is a fantastic channel.

Eh. His older videos are indeed phenomenal, but newer ones are "you won't believe what happened, right after this sponsor break"

Re: Preliminary report into Air India crash released

#390

Post by burnt-resistor »

epolanski wrote: post #331
burnt-resistor wrote: post #320

Earlier quoted context omitted.

Bad analogy because pilots are trained and rehearse and practice memory items until they are instinctual. > impossible by design. Deflecting that the human is the weakest part of the system. One or other may have panicked and made a mistake, made a mistake unintentionally, went crazy and doomed the flight, or intentionally doomed the flight for some socioeconomic reasons. These are speculative possibilities that we d…

Forget my words then and take those from aviation experts. The fact that a pilot would cut off fuel from both engines, in sequence while taking off is virtually impossible to happen unless deliberate. Hence the hand brake comparison, it does not come natural to use it while driving.

It was done. Yes. There is no way to determine from the evidence why it was done, how much conscious or not thought was put into it, or the thought process behind it.
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