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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

#171

Why can the pilot shut off the fuel during takeoff?

Fire, probably. But also, how complicated would you make the system if you needed to prevent certain switches from working during certain times of flight? At some point... we're all just in the hands of the people in the cockpit.

I can't put my car into reverse gear while driving down the freeway.

Re: Preliminary report into Air India crash released

#172

Earlier quoted context omitted.

Suggest a system that would prevent this, but only this, without causing other risks.

Disable the fuel system cutoff controls during the takeoff climb phase of flight. Once the aircraft loses contact with the runway, these controls shouldn't function without tripping certain thresholds (speed & altitude), or following a two-man procedure that is physically impossible to execute solo. In any other flight regime, the controls function as originally designed. The danger of a burning engine is irrelevant…

Sounds good, but I'm not sure I trust Boeing outsourced software developers to implement that absolutely correctly.

Re: Preliminary report into Air India crash released

#173

Earlier quoted context omitted.

Suggest a system that would prevent this, but only this, without causing other risks.

Disable the fuel system cutoff controls during the takeoff climb phase of flight. Once the aircraft loses contact with the runway, these controls shouldn't function without tripping certain thresholds (speed & altitude), or following a two-man procedure that is physically impossible to execute solo. In any other flight regime, the controls function as originally designed. The danger of a burning engine is irrelevant…

Now you created a fuel system cutoff control inhibition system which may malfunction in its own ways, e.g., refuse to cut off fuels from a burning engine because it thinks the plane is too low due to faulty altimeter reading.

Re: Preliminary report into Air India crash released

#174

Even if the plane had no power, why couldn't they have glided it down safely?

I’ll take this as an honest question. The simple answer: too much mass, no clear landing path, not enough speed or altitude to turn to find one and glide to it. In short, not enough time. Once the engines cut, that thing probably dropped like a brick.

Re: Preliminary report into Air India crash released

#176

> 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…

Not that humans are known to behave rationally when trying to commit suicide, but it’s interesting that the switches were re-engaged successfully without protest or a fight. It’s just an interesting detail to wonder about.

The reasoning I’ve heard is: it didn’t matter anymore, the damage was already done and there was no way any attempts at recovering from it would have been successful.

Re: Preliminary report into Air India crash released

#177
post #35

Earlier quoted context omitted.

Does the Flight Data Recorder consider the physical position of the fuel switches or does it get the information from some fly-by-wire part that could be buggy? The conversation would suggest that the switches were in CUTOFF position, but there is also a display that summarizes the engine status. There is no conversation that mentions flipping the switch to RUN again. EDIT: Why is there no Cockpit Video Recorder? The…

> EDIT: Why is there no Cockpit Video Recorder? The days of limited storage are over. Pilots unions are dead against it.

Are you actually using a tragedy like this to launch an assault on organized labour?

Re: Preliminary report into Air India crash released

#178
post #35

Earlier quoted context omitted.

> EDIT: Why is there no Cockpit Video Recorder? The days of limited storage are over. Pilots unions are dead against it.

Are you actually using a tragedy like this to launch an assault on organized labour?

[dead]

Re: Preliminary report into Air India crash released

#179
post #66

Earlier quoted context omitted.

I don't understand your question. I have done this myself, am I completely sure?

Did you mean to say you can activate the switches with one hand simultaneously ? That is probably what the above commenter assumed you meant. Since lifting and twisting two switches simultaneously with one hand seems challenging.

Above commenter said _quickly_, not simultaneously
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