Preliminary report into Air India crash released • Hacker News Board

Re: Preliminary report into Air India crash released

#681

Post by gmokki » Sat, Jul 12, 2025, 5:29 PM UTC

yason wrote: post #672

It is known that the switches cannot effectively be flipped by accident. It is known that the switches were set to "cut-off" because they were then later restored to "run", so it was not an electrical fault (i.e. switches pointing to run but reporting cut-off). Pilot dialogue and engine telemetry confirms the cause of power loss was fuel cut-off. The question I can't help but think is how did the pilot realize it was…

I would assume that the engines cur of due to fault in the shared control system. And to restore power the pilots toggled the switches to off and then back on to get them running again.

Hopefully the timestamps tell if the engines lost power before switches were turned off? Or is there some time window that was not recorded due to the lost power to systems?

Re: Preliminary report into Air India crash released

#682

Post by demondlee » Sat, Jul 12, 2025, 5:38 PM UTC

fsckboy wrote: 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…

Not possible. Two fuel cutoffs. Two engines. Two intentional acts in rapid succession. Plane would have survived one cutoff. It is what it appears. Captain crashed the plane.

Re: Preliminary report into Air India crash released

#683

Post by lxgr » Sat, Jul 12, 2025, 5:43 PM UTC

ekianjo wrote: post #420

lxgr wrote: post #309

Earlier quoted context omitted.

Free to passengers doesn’t mean free to the airline, and Starlink in commercial airliners is very new.

sure but if the airline already pays for the service for passengers surely it can be used for the planes as well

Not necessarily. Required certifications, SLAs etc. for safety critical systems are vastly different from those only handling passenger entertainment/connectivity. For example, Iridium has been around for almost 30 years now (launched in 1998), but it only became certified for safety of life applications at sea in 2019, and for aviation around 2010.

Many planes still use completely separate systems for non-critical communication (often Ku or Ka band based geostationary satelliets) and for ATC or operational communication (usually L-band based Inmarsat or Iridium) as a result.

Re: Preliminary report into Air India crash released

#684

Post by whatever1 » Sat, Jul 12, 2025, 5:46 PM UTC

topbanana wrote: post #648

whatever1 wrote: post #645

These airplanes reject a lot of the pilot inputs if they don’t align with the expectations. Any idea why the system even allows the cut engine fuel input at that time of flight? Sounds to me that it should be just ignored. Even if both engines were on fire while climbing that early, what could cutting fuel offer?

In case of engine fire they need to cut fuel

In general yes. But that early in the takeoff sequence cutting fuel will only kill you. If the engines can still provide thrust, I would take it.

Re: Preliminary report into Air India crash released

#685

Post by demondlee » Sat, Jul 12, 2025, 5:48 PM UTC

zamadatix wrote: post #130

fsckboy wrote: 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…

One of the nice things about finally having the preliminary report is I get to stop hearing all of the same assumptions/theories/YouTuber said/"a guy I know got a leaked report"/etc in water cooler talk at work because the preliminary report solidly disproved all of them so far. If anyone even had and stuck with an idea matching this report it wouldn't have stood out in the conversations anyways. The collection of co…

Double engine failure was confirmed, not disproven. RAT deployment was confirmed, not disproved. Pilot error, confirmed, not disproven. Preliminary and final aviation reports are mostly guesses.

Re: Preliminary report into Air India crash released

#686

Post by tim333 » Sat, Jul 12, 2025, 5:55 PM UTC

noqc wrote: post #661

SAI_Peregrinus wrote: post #629

Assuming this is a murder-suicide and not a mistake or malfunction somehow, it's very damning of the FAA's policy to revoke the pilot's licenses of anyone seeking treatment for mental health issues. This was in India and thus not FAA jurisdiction, but it still would be a case where an untreated mental health issue lead to hundreds of deaths. By making pilots choose between their careers & medical treatment (since the…

The murder suicide angle isn't particularly worthy of assumption yet. Have you ever put your phone in the fridge? Pilots deactivate the fuel cutoff at the end of the final taxi to the gate. This makes flipping these switches a practiced maneuver , capable of being performed without conscious thought, regardless of whether they came with safety locks installed. Brain farts are a real phenomenon, and an accidental fuel…

Turning the fuel off seems roughly equivalent to turning the ignition off when you've parked your car. It's really something rather unlikely to do as a brain fart during takeoff.

Re: Preliminary report into Air India crash released

#687

Post by sjsdaiuasgdia » Sat, Jul 12, 2025, 6:08 PM UTC

tim333 wrote: post #686

noqc wrote: post #661

Earlier quoted context omitted.

The murder suicide angle isn't particularly worthy of assumption yet. Have you ever put your phone in the fridge? Pilots deactivate the fuel cutoff at the end of the final taxi to the gate. This makes flipping these switches a practiced maneuver , capable of being performed without conscious thought, regardless of whether they came with safety locks installed. Brain farts are a real phenomenon, and an accidental fuel…

Turning the fuel off seems roughly equivalent to turning the ignition off when you've parked your car. It's really something rather unlikely to do as a brain fart during takeoff.

Most commercial aircraft have quite a few more buttons, knobs, levers, dials, etc than a car.

Re: Preliminary report into Air India crash released

#688

Post by jahewson » Sat, Jul 12, 2025, 6:10 PM UTC

noqc wrote: post #661

SAI_Peregrinus wrote: post #629

Assuming this is a murder-suicide and not a mistake or malfunction somehow, it's very damning of the FAA's policy to revoke the pilot's licenses of anyone seeking treatment for mental health issues. This was in India and thus not FAA jurisdiction, but it still would be a case where an untreated mental health issue lead to hundreds of deaths. By making pilots choose between their careers & medical treatment (since the…

The murder suicide angle isn't particularly worthy of assumption yet. Have you ever put your phone in the fridge? Pilots deactivate the fuel cutoff at the end of the final taxi to the gate. This makes flipping these switches a practiced maneuver , capable of being performed without conscious thought, regardless of whether they came with safety locks installed. Brain farts are a real phenomenon, and an accidental fuel…

Brain farts are literally not a real phenomenon.

Re: Preliminary report into Air India crash released

#689

Post by patch_cable » Sat, Jul 12, 2025, 6:14 PM UTC

yason wrote: post #672

It is known that the switches cannot effectively be flipped by accident. It is known that the switches were set to "cut-off" because they were then later restored to "run", so it was not an electrical fault (i.e. switches pointing to run but reporting cut-off). Pilot dialogue and engine telemetry confirms the cause of power loss was fuel cut-off. The question I can't help but think is how did the pilot realize it was…

I’m more familiar with the 737 (as a hobby, not as a pilot), but for that aircraft the “loss of thrust on both engines” checklist has the start levers as the second item on the list.

Note that in the checklist I am looking at the goal is to restart the engines rather than diagnose the failure and that involves these levers. I suspect you’d notice pretty quickly if they were not in the expected location.

Re: Preliminary report into Air India crash released

#690

Post by jolt42 » Sat, Jul 12, 2025, 6:16 PM UTC

justsid wrote: post #628

macintux wrote: post #245

Earlier quoted context omitted.

> This idea strikes me as even more unlikely than someone shifting their moving vehicle into reverse while intending to activate the window wipers. I suspect you've never driven an older vehicle with the shifter on the steering column.

But the 787 doesn’t have an easily confused layout like that. The landing gear lever and fuel cut off switches are not two stalks on the yoke. Aircraft cockpits are deliberately designed in such a way that important things have differently shaped actuators that feel different from each other. Precisely so that you are not accidentally flipping the wrong switch by accident.

Actually the birth of Human Factors was related to this... Alphonse Chapanis, a psychologist working at the Army Air Force Aero Medical Lab in 1942, investigated the issue and discovered a design flaw. He observed that the controls for the flaps and the landing gear in the B-17 cockpit were nearly identical and located close to each other.