Preliminary report into Air India crash released • Hacker News Board

Re: Preliminary report into Air India crash released

#51

Post by cosmicgadget » Fri, Jul 11, 2025, 10:49 PM UTC

lazystar wrote: post #44

ggreer wrote: post #30

Earlier quoted context omitted.

The only affected models were 737s with the 766AT613-3D fuel control switch. The bulletin recommended that other models be inspected and any defects reported. It's unclear if any 787s were discovered to have the issue. Also the preliminary report mentions that the switches were replaced in 2019 and 2023, after the 2018 bulletin.

still, it at least shows that there's been issues with the locking mechanism in the past. inadvertently bumping something that was assumed to be locked is a simpler theory; i find it hard to believe that a murder suicider would take this route, when the china nosedive option is easier, faster, and has a higher chance of success.

Cutting fuel just after takeoff leaves almost zero time for the other pilot to recover.

Re: Preliminary report into Air India crash released

#52

Post by joshAg » Fri, Jul 11, 2025, 10:51 PM UTC

mdavid626 wrote: post #45

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…

Well, can you move it back, when accidentally activated?

at least one of the pilots did. according to the preliminary report, the switches were only in the cutoff position for 10 seconds before being switched back to the run position and the engines started to spin up again

Re: Preliminary report into Air India crash released

#53

Post by sillysaurusx » Fri, Jul 11, 2025, 10:51 PM UTC

cosmicgadget wrote: post #47

The report says the co-pilot was flying so it's most likely the pilot cut the fuel?

Correct. Which means it’s the older of the two.

Re: Preliminary report into Air India crash released

#54

Post by cosmicgadget » Fri, Jul 11, 2025, 10:52 PM UTC

dcreater wrote: post #46

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…

Do you know if the mechanical position of the switch guarantees its electronic state without any possibility for hardware malfunction? If no, then you are claiming a person made one of the most grave acts of inhumanity ever. This sounds to me like an electronics issue - an intermittent, inadvertent state transition likely due to some PCB component malfunction

Murder-suicide has happened on a few occasions. How many times has your malfunction occurred on an aircraft fuel system?

Re: Preliminary report into Air India crash released

#55

Post by pigbearpig » Fri, Jul 11, 2025, 10:55 PM UTC

__turbobrew__ wrote: post #49

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…

I wonder if the switches are still in tact after the crash? Can they verify that the switches are mechanically sound? If so, seems highly likely it was intentional.

There are pictures of them in the report.

Re: Preliminary report into Air India crash released

#56

Post by [deleted] » Fri, Jul 11, 2025, 10:57 PM UTC

__turbobrew__ wrote: post #49

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…

I wonder if the switches are still in tact after the crash? Can they verify that the switches are mechanically sound? If so, seems highly likely it was intentional.

[deleted]

Re: Preliminary report into Air India crash released

#57

Post by sillysaurusx » Fri, Jul 11, 2025, 10:58 PM UTC

[flagged]

Re: Preliminary report into Air India crash released

#58

Post by alphabettsy » Fri, Jul 11, 2025, 10:59 PM UTC

Jtsummers wrote: post #39

breadwinner wrote: post #37

Earlier quoted context omitted.

> post-flight muscle memory (of shutting off the engines) kicked in Possible, and if so it is too early to conclude it was murder-suicide. See also: https://www.thehindu.com/news/national/dgca-slaps-80-lakh-fi...

The report shows 0 flight hours during the prior 24 hours for both pilots, and 7 hours and 6 hours each for the previous 7 days. It seems they were both fresh pilots for this flight.

that doesn’t tell us they were fresh. Only that they hadn’t flown. They could’ve slept 0 hours before or any number of things.

Re: Preliminary report into Air India crash released

#59

Post by stefan_ » Fri, Jul 11, 2025, 11:00 PM UTC

dcreater wrote: post #46

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…

Do you know if the mechanical position of the switch guarantees its electronic state without any possibility for hardware malfunction? If no, then you are claiming a person made one of the most grave acts of inhumanity ever. This sounds to me like an electronics issue - an intermittent, inadvertent state transition likely due to some PCB component malfunction

And then 10s later the switches magically fixed themselves? The likely not electronically connected switches since that would compromise engine redundancy?

Re: Preliminary report into Air India crash released

#60

Post by nikanj » Fri, Jul 11, 2025, 11:01 PM UTC

bgwalter wrote: post #25

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…

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…

Airlines are decades behind on tech. You can get satellite internet almost anywhere on the planet and GPS can give you ten-foot accurate positioning, but we've still _lost_ planes because we haven't mandated a system that sends the realtime position of the plane over the satellite internet. The days of limited storage are still going strong in the industry.