frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

OpenAI’s Windsurf deal is off, and Windsurf’s CEO is going to Google

https://www.theverge.com/openai/705999/google-windsurf-ceo-openai
457•rcchen•6h ago•306 comments

ETH Zurich and EPFL to release a LLM developed on public infrastructure

https://ethz.ch/en/news-and-events/eth-news/news/2025/07/a-language-model-built-for-the-public-good.html
345•andy99•9h ago•44 comments

Replication of Quantum Factorisation Records with an 8-bit Home Computer [pdf]

https://eprint.iacr.org/2025/1237.pdf
25•sebgan•1h ago•1 comments

Faking a JPEG

https://www.ty-penguin.org.uk/~auj/blog/2025/03/25/fake-jpeg/
109•todsacerdoti•5h ago•26 comments

Preliminary report into Air India crash released

https://www.bbc.co.uk/news/live/cx20p2x9093t
157•cjr•7h ago•255 comments

jank is C++

https://jank-lang.org/blog/2025-07-11-jank-is-cpp/
200•Jeaye•10h ago•69 comments

FEMA Didn’t Answer Thousands of Calls From Flood Survivors

https://www.nytimes.com/2025/07/11/climate/fema-missed-calls-texas-floods.html
52•standardUser•1h ago•11 comments

A software conference that advocates for quality

https://bettersoftwareconference.com/
56•leoncaet•6h ago•33 comments

Leveraging Elixir's hot code loading capabilities to modularize a monolithic app

https://lucassifoni.info/blog/leveraging-hot-code-loading-for-fun-and-profit/
10•ronxjansen•3d ago•1 comments

Dict Unpacking in Python

https://github.com/asottile/dict-unpacking-at-home
48•_ZeD_•3d ago•11 comments

HDD Clicker generates HDD clicking sounds, based on HDD Led activity

https://www.serdashop.com/HDDClicker
34•starkparker•3h ago•14 comments

Andrew Ng: Building Faster with AI [video]

https://www.youtube.com/watch?v=RNJCfif1dPY
176•sandslash•1d ago•46 comments

Bill Atkinson's psychedelic user interface

https://patternproject.substack.com/p/from-the-mac-to-the-mystical-bill
381•cainxinth•16h ago•204 comments

Upgrading an M4 Pro Mac mini's storage for half the price

https://www.jeffgeerling.com/blog/2025/upgrading-m4-pro-mac-minis-storage-half-price
314•speckx•13h ago•199 comments

Measuring power network frequency using junk you have in your closet

https://halcy.de/blog/2025/02/09/measuring-power-network-frequency-using-junk-you-have-in-your-closet/
20•zdw•5h ago•4 comments

Astronomers race to study interstellar interloper

https://www.science.org/content/article/astronomers-race-study-interstellar-interloper
108•bikenaga•12h ago•56 comments

Apple vs the Law

https://formularsumo.co.uk/blog/2025/apple-vs-the-law/
346•tempodox•21h ago•351 comments

Repaste Your MacBook

https://christianselig.com/2025/07/repaste-macbook/
185•speckx•15h ago•91 comments

Monorail – Turn CSS animations into interactive SVG graphs

https://muffinman.io/monorail/
51•stanko•3d ago•5 comments

Activeloop (YC S18) Is Hiring AI Search and Python Back End Engineers(Onsite,MV)

https://careers.activeloop.ai/
1•davidbuniat•6h ago

Introduction to Digital Filters

https://ccrma.stanford.edu/~jos/filters/
38•ofalkaed•8h ago•7 comments

Computer Scientists Figure Out How to Prove Lies

https://www.quantamagazine.org/computer-scientists-figure-out-how-to-prove-lies-20250709/
12•pseudolus•2d ago•1 comments

OpenAI delays launch of open weights model

https://twitter.com/sama/status/1943837550369812814
64•martinald•2h ago•50 comments

'123456' password exposed chats for 64M McDonald's job applicants

https://www.bleepingcomputer.com/news/security/123456-password-exposed-chats-for-64-million-mcdonalds-job-applicants/
82•nan60•6h ago•47 comments

Show HN: RULER – Easily apply RL to any agent

https://openpipe.ai/blog/ruler
54•kcorbitt•10h ago•9 comments

Tell HN: uBlock Origin on Chrome is finally gone

73•ipsum2•2h ago•40 comments

Lead pigment in turmeric is the culprit in a global poisoning mystery (2024)

https://www.npr.org/sections/goats-and-soda/2024/09/23/nx-s1-5011028/detectives-mystery-lead-poisoning-new-york-bangladesh
315•perihelions•12h ago•156 comments

At Least 13 People Died by Suicide Amid U.K. Post Office Scandal, Report Says

https://www.nytimes.com/2025/07/10/world/europe/uk-post-office-scandal-report.html
568•xbryanx•16h ago•482 comments

AWS Free Tier Changes on July 15, 2025

https://freetier.co/articles/aws-free-tier-changes-july-15-2025
9•coop182•4h ago•1 comments

2-4 wire converters / hybrids (2009)

https://sound-au.com/appnotes/an010.htm
10•userbinator•4d ago•1 comments
Open in hackernews

Preliminary report into Air India crash released

https://www.bbc.co.uk/news/live/cx20p2x9093t
157•cjr•7h ago
Report: https://aaib.gov.in/What%27s%20New%20Assets/Preliminary%20Re...

Comments

rawgabbit•7h ago
Quote:

       As we just reported, the report says that according to data from the flight recorder both the fuel control switches, which are normally used to switch the engines on or off when on the ground, were moved from the run to the cutoff position shortly after takeoff.  This caused both engines to lose thrust.

The preliminary report suggests this is pilot error.
lazharichir•7h ago
From my (limited) understanding you cannot really switch these off inadvertently as they require a couple of actions in order to be switched off. So it would mean one of the pilots switched these off (and they were a few seconds later switched on again but it was too late).

But there was audio, too, and one pilot asked the other "why did you switch these off" and the second one said "I didn't".

Was there are third one in the jump seat?

rawgabbit•7h ago
The report only said the copilot was flying and the pilot was monitoring.
fracus•6h ago
Sounds likely that one of them was sabotaging the flight.
zihotki•5h ago
It does not suggest that. It only says they were turned off and no other conclusion given.
mallets•7h ago
Well, shit. Suicidal?

And this can't possibly be all the audio if the other pilot noticed the switch position, I would expect a lot more cussing and struggle.

So they didn't notice the switch position? The switch was in the right position but not really? Is this a rarely used switch that one might not look at (or know where to look) during regular use?

10 seconds between OFF and ON.

chupchap•6h ago
From what I've read, it comes on the display as a warning
lazide•3h ago
Dual engine failure on takeoff gives them about as much time to react as if the front passenger grabbed the steering wheel while on a windy mountain road and yanked them off a cliff.

It only takes a few seconds to completely screw everyone, but a bit longer for the consequences to occur.

rwmj•7h ago
The India AAIB website (https://aaib.gov.in/) is not responding ... For anyone who read the report, was there information about the age & experience of the pilots?
mtmail•5h ago
56 years old, 15638 hours (8596 on this type) and 32 years old, 3403 hours (1128 on this type). Page 11 of the PDF report.
foldr•7h ago
Report PDF here: https://aaib.gov.in/What's%20New%20Assets/Preliminary%20Repo...
belter•7h ago
Not accessible. Have they heard about S3 ?
foldr•7h ago
It loads for me, so I think the link will be useful for some people at least.
shoghicp•6h ago
mirror https://web.archive.org/web/20250711203907/https://aaib.gov....
d_silin•6h ago
Report page that matters: https://x.com/exodusorbitals/status/1943782924576309732
decimalenough•6h ago
> 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 switches in question are also built so they cannot be triggered accidentally, they need to be unlocked first by pulling them out.

> In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff. The other pilot responded that he did not do so.

And both pilots deny doing it.

It's difficult to conclude anything other than murder-suicide.

chupchap•6h ago
Or a mechanical failure
ceejayoz•6h ago
Both switches, at slightly different times? Seems pretty unlikely.
userbinator•2h ago
A rodent chewing on wires. Vibration-induced chafing. Tin whiskers causing an intermittent short. There are many possibilities, those came to mind first.
Epa095•2h ago
But why does the pilot then comment that they are in the CUTTOF position and move it to RUN? A mechanical failure would have to also move the physical switch in the cockpit for the audio recording to make sence.
userbinator•1h ago
You have the exact CVR audio? The report says "one of the pilots is heard asking the other why did he cutoff" which I interpreted to mean one of them noticed the engines shutting down, and asked the other if he did that.
bronson•1h ago
Then he would have asked the other pilot why the engines are shutting down. It seems a lot more probable that he glanced at the switches before asking such an explicit question.
apical_dendrite•1h ago
We know that the switches physically moved from the run to the cutoff position because one of the pilots noted that they were in the wrong position. We know that they were moved back to the run position because they found in that position. I don't understand how a short could explain that - it really seems like someone would have had to physically move the switches.
ceejayoz•6h ago
> 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.

> As per the EAFR, the Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN at about 08:08:52 UTC.

Damn. That's pretty quick to diagnose and take action.

Boeing's probably gonna have a big sigh of relief over this one.

dehrmann•3h ago
> Boeing's probably gonna have a big sigh of relief over this one.

The 787 is 15 years old, and this particular plane was 10 years old. It always seemed unlikely to be a major, new issue. My money was actually on maintenance.

alephnerd•6h ago
> It's difficult to conclude anything other than murder-suicide.

Is it possible it could have been an accident or a mistake by one of the pilots? How intention-proofed are engine cutoffs?

ummonk•6h ago
You have to pull the switches out (against a spring) to be able to move them over a notch and flip them. Not really something you can just mistake for another switch or bump into by accident.

I'd liken it to turning off the ignition by turning the key while driving your car. Possibly something that could happen if you're really fatigued, but requires quite a mental lapse.

joezydeco•6h ago
Report says the switches went to cutoff one second apart from each other. Can a human do the physical operation on two switches that quickly?
snypher•6h ago
There's a good photo of them here; https://theaircurrent.com/aviation-safety/ai171-investigatio...

You can do them both with one hand.

zihotki•5h ago
Are you completely sure you can considering that they are spring loaded and they are like 7-10cm apart judging by the size of other controls?
snypher•4h ago
I don't understand your question. I have done this myself, am I completely sure?
cosmicgadget•4h ago
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.
mvdtnz•3h ago
It didn't happen simultaneously so this is irrelevant.
cosmicgadget•3h ago
It is relevant to the interaction I replied to.
ryandrake•11m ago
You’re the only one who said “simultaneously.”
lanna•2h ago
Above commenter said _quickly_, not simultaneously
cosmicgadget•3m ago
Jesus...

joey: Can you switch them quickly?

snypher: You can do them with one hand. [Ed. This is ambiguous and could be read as "one hand, simultaneously". In fact, doing it with one hand non-simultaneously would be a weird claim to make of a simple knob]

zihotki: Really? They are not close together and have a spring mechanism. [Ed. Seems to believe snypher is claiming simultaneous operation]

snypher: I am confused by the response.

Me: [Tries to facilitate clarification]

ajb•4h ago
If you do them both with one hand, would they not be moved at the same instant rather than 1 second apart?
lazide•4h ago
They require a per-switch motion, so unlikely.
arp242•2h ago
Is there just one set of switches? Or do both pilots have their own set?
heisenbit•5h ago
The timing is really curious.

08:08:35 Vr

08:08:39 Liftoff

08:08:42 Engine 1 cut-off

08:08:42 Engine 2 cut-off

08:08:47 minimum idel speed reached

?? One pilot to other: why cut-off. Other: Did not do it

08:08:52 Engine 1 run

08:08:52 Engine 2 run

1 second to switch them both off and then 4 seconds to switch them both on. No one admitted to switch them off. They are probably going with fine comb over the audio and also the remains of the chared switches.

Looks like the engines react very quickly to cut-off so it is not clear whether the question about the cut-off is prompted by a glance to the switches or the feel of the airplane.

The big question is whether the switches were moved or something made it seem as if the switches were moved.

cosmicgadget•4h ago
Well in the murder-suicide scenario it makes sense for the culprit to turn them off as quickly as possible. The longer time to turn them on could plausibly be a struggle or simply needing to fly the plane while reaching for each switch individually.
XorNot•1h ago
Assuming the person trying to kill themselves and a plane load of people would respond in an expected way to inquiry is also just a mistake.

It's not a rational decision, so there's no reason to expect rational decision making or explanation on the output.

magicalhippo•1h ago
Is it possible to rest the switch on the notch? Does the switch make contact if the switch is in the RUN position but the switch is not completely down?

That is, is it possible they flipped the switches over to RUN but did not seat the switches properly, and instead leaving them on top of the notch, with later vibration causing the switches to disengage?

Just trying to think of some semi-plausible non-active causes.

xenadu02•5h ago
It could be defective switch springs, fatigue-induced muscle memory error, or something else. The pilot who did it saying he did not may not have realized what he did. It's pretty common under high workload when you flip the wrong switch or move a control the wrong way to think that you did what you intended to do, not what you actually did.

That said Boeing could take a page out of the Garmin GI275. When power is removed it pops up a "60s to shutdown dialog" that you can cancel. Even if you accidentally press SHUTDOWN it only switches to a 10s countdown with a "CANCEL" button.

They could insert a delay if weight on wheels is off. First engine can shutdown when commanded but second engine goes on 60s delay with EICAS warning countdown. Or just always insert a delay unless the fire handle is pulled.

Still... that has its own set of risks and failure modes to consider.

rogerrogerr•4h ago
Delay is probably worse - now you're further disassociating the effect of the action from the action itself, breaking the usual rule: if you change something, and don't like the effect, change it back.
aerospace83•3h ago
Armchair safety/human factors engineering, gotta love HN.
zahlman•3h ago
This is a place that puts "Hacker" in the name despite the stigma in the mainstream. Given the intended meaning of the term, I would naturally expect this to be a place where people can speculate and reason from first principles, on the information available to them, in search of some kind of insight, without being shamed for it.

You don't have to like that culture and you also don't have to participate in it. Making a throwaway account to complain about it is not eusocial behaviour, however. If you know something to be wrong with someone else's reasoning, the expected response is to highlight the flaw.

macintux•1h ago
For me it's mainly about intent/unearned confidence.

If someone is speculating about how such a problem might be solved while not trying to conceal their lack of direct experience, I'm fine with it, but not everyone is.

If someone is accusing the designers of being idiots, with the fix "obvious" because reasons, well, yeah, that's unhelpful.

sdgsdgssdg•54m ago
(Different user here) Hacker News' "culture" is one of VC tech bros trying to identify monopolies to exploit, presumably so they can be buried with all their money when they die. There's less critical thinking here than you'd find in comments sections for major newspapers.
aerospace83•54m ago
> That said Boeing could take a page out of the Garmin GI275

This is not "reasoning from first principles". In fact, I don't think there is any reasoning in the comment.

There is an implication that an obvious solution exists, and then a brief description of said solution.

I am all for speculation and reasoning outside of one's domain, but not low quality commentary like "ugh can't you just do what garmin did".

This is not a throwaway, I'm a lurker, but was compelled to comment. IMHO HN is not the place for "throwaway" ad hominems.

pixl97•3h ago
When your engine catches on fire/blows apart on takeoff you want to cut fuel as fast as possible.
OneMorePerson•3h ago
Was thinking this same thing. A minute feels like a long time to us (using a Garmin as the example said) but a decent number of airplane accidents only take a couple minutes end to end between everything being fine and the crash. Building an insulation layer between the machine and the experts who are supposed to be flying it only makes it less safe by reducing control.
p1mrx•1h ago
Proposed algorithm: If the flight computer thinks the engine looks "normal", then blare an alarm for x seconds before cutting the fuel.

I wonder if there have been cases where a pilot had to cut fuel before the computer could detect anything abnormal? I do realize that defining "abnormal" is the hardest part of this algorithm.

SJC_Hacker•1h ago
If its both engines you're fucked anyway if its shortly after takeoff.

But I'm an advocate of KISS. At a certain point you have to trust the pilot is not going to something extremely stupid/suicidal. Making overly complex systems to try to protect pilots from themselves leads to even worse issues, such as the faulty software in the Boeing 737-MAX.

lazystar•6h ago
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 supply or cutoff fuel to the engines. The fuel control switch has a locking feature to prevent inadvertent operation that could result in unintended switch movement between the fuel supply and fuel cutoff positions. In order to move the switch from one position to the other under the condition where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch position. If the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown. Boeing informed the FAA that the fuel control switch design, including the locking feature, is similar on various Boeing airplane models. The table below identifies the affected airplane models and related part numbers (P/Ns) of the fuel control switch, which is manufactured by Honeywell.

> If the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown

barbazoo•6h ago
Same manufacturer, Air India 171 was a 787-8 though.
shoghicp•6h ago
The affected table includes these models as well: 787-8, -9, and -10
barbazoo•6h ago
Thanks for pointing it out.
ggreer•6h ago
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.
lazystar•5h ago
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.
cosmicgadget•5h ago
Cutting fuel just after takeoff leaves almost zero time for the other pilot to recover.
bombcar•4h ago
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?

cosmicgadget•3h ago
I think engine fires are still more common than suicidal pilots and inadvertant fuel shutoff activations.
bombcar•3h ago
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.

cosmicgadget•2h ago
The flip flop thing is a neat idea since a single engine can typically maintain level flight and two burning engines is rare.
stephen_g•1h ago
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.

ggreer•3h ago
The preliminary report says the switches were triggered a second apart, so it would have to have been faulty switches and two inadvertent bumps. That seems unlikely to me.
somat•1h ago
Within a second apart. If I read the report right. The time resolution of the recorder?

And yes, it does sound like it was probably intentional. I would still like to see an engineering review of the switch system. Are they normally open or normally closed, In the end the switch instructs the FADEC to cut the fuel, but where does the wiring go in the meantime? what software is in the path? would the repair done before the flight be in that area?(pilot defect report for message STABS POS XCDR), and perhaps compromised the wires?

lazystar•12m ago
.1 second apart, not 1 second.
tekla•6h ago
They don't mention the locking mechanism being disabled
cosmicgadget•5h ago
Is it easy to inadvertantly move both switches in such a scenario?
lysace•4h ago
No.
sandspar•1h ago
The switches are spring-loaded, notched in place, and have a rubber knob on the top. A pilot must squeeze the knob, remove the switch from its ON notch, press the switch, click it into the OFF notch, then release the knob.

Doing it accidentally is impossible.

mdavid626•5h ago
Well, can you move it back, when accidentally activated?
joshAg•5h ago
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
the__alchemist•4h ago
Yes, and it restarts the engines, but it takes on the order of seconds; too long at that altitude. One of the pilots did that, but it was too late.
TylerE•1h ago
More like 30 seconds. Just throttling an already running engine up from idle (which is quite a bit above zero throttle in most respects) takes seconds.
alvah•3h ago
Turbines take a while to spin up again, it's not like start/stop in a car.
stetrain•2h ago
They were moved back to the run position 10 seconds after being switched off, and the engines were in the very early stages of restarting by the time of the crash. It was too late.
sillysaurusx•5h ago
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 was a mass murder.

longos•3h ago
If this is what actually happened it would be the second in recent memory: https://en.wikipedia.org/wiki/Germanwings_Flight_9525.
decimalenough•3h ago
Third, since there's no other plausible explanation for this and China has classified the report.

https://en.wikipedia.org/wiki/China_Eastern_Airlines_Flight_...

lanna•3h ago
Fourth? https://en.wikipedia.org/wiki/Malaysia_Airlines_Flight_370#M...
pineal•2h ago
Fifth. https://en.wikipedia.org/wiki/EgyptAir_Flight_990
CBMPET2001•1h ago
Sixth (and this one is pretty indisputable): https://en.wikipedia.org/wiki/LAM_Mozambique_Airlines_Flight...
ekianjo•46m ago
We dont know about that one at all.
bdangubic•14m ago
we do here on HN :)
darth_avocado•4h ago
One would assume a toggle like that would come with blaring alarms and blinking lights… right? Right??

Edit: It also seems like the engine cutoff is immediate after the toggle. I wonder if a built in delay would make sense for safety.

lazide•4h ago
Low altitude, stall, and impact with terrain certainly will.

And with how low and slow they were during takeoff, those would have been going off almost instantly.

cjbprime•3h ago
> I wonder if a built in delay would make sense for safety.

(Presumably delaying the amount of time before a raging engine fire stops receiving fuel would also have an impact on safety?)

russdill•3h ago
These switches are operated at startup and shutdown. So pretty much daily. By pilots and likely maintenance crews. Such a defect with not to unnoticed for long
noduerme•1h ago
What is "01 second" as quoted above? If it's 1 second, you could possibly conclude that it was intentional. If it's 0.1 second you might think it was an accident and the lock was disengaged.
sugarpimpdorsey•9m ago
Totally different airplane with a totally different flight deck, designed generations apart. The fact that the manufacturer is the same is irrelevant.

You are trying to draw parallels between the ignition switch in a 1974 Ford Pinto and a 2025 Ford Mustang as if there could be a connection. No.

sbuttgereit•2m ago
[delayed]
ummonk•6h ago
Yeah and the other pilot flipped the switches back on and one of the engines started spooling up but it was too late.

Murder-suicide looks like the likely conclusion, given that flipping the cutoff switches requires a very deliberate action. That said, it's not entirely impossible that due to stress or fatigue the pilot had some kind of mental lapse and post-flight muscle memory (of shutting off the engines) kicked in when the aircraft lifted off.

breadwinner•5h ago
> 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...

Jtsummers•5h ago
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.
alphabettsy•5h ago
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.
bgwalter•6h ago
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 days of limited storage are over.

tekla•6h ago
Yes there is.
ssl232•5h ago
> EDIT: Why is there no Cockpit Video Recorder? The days of limited storage are over.

Pilots unions are dead against it.

bombcar•4h ago
And now some pilots are dead.

Just allow cockpit video recorders, and if they're ever used for anything, the pilots (or their heirs) get $250k in cash.

gnulinux996•2h ago
Are you actually using a tragedy like this to launch an assault on organized labour?
ekianjo•43m ago
And Pilots end up dead because of it.
nikanj•4h ago
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.
karlgkk•1h ago
There are reasons they don’t. This is a deceptively difficult problem

Cost is a big one (satellite data is still quite a bit more expensive than you think, especially with many stations)

And by stations, I mean aircraft. There are a TON. Current constellations probably wouldn’t even be able to handle half the current aircraft transmitting all at once. Bandwidth, in the physical sense, becomes a limiting factor

Coverage (different constellations have different coverage, which means planes would not have transmit guarantees depending on flight path). So you’d have huge gaps anyways

There have been alternative solutions posed, some of which are advancing forward. For example, GPS aware ELTs that only transmit below certain altitudes. But even that has flaws

Anyways I think we’ll see it in the next decade or two, but don’t hold your breath

ekianjo•42m ago
> Cost is a big one (satellite data is still quite a bit more expensive than you think, especially with many stations)

You get free Starlink on several airlines now, so won't that be a solved problem soon?

WalterBright•1h ago
I've had discussions on HN with people who insisted that having a video camera always pointed out the control tower at the runway was some sort of impossibility. Despite every 7-11 having such a system.

This would leave accident investigators with a lot of work to do to try to figure out how a collision happened.

dcreater•5h ago
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

cosmicgadget•5h ago
Murder-suicide has happened on a few occasions. How many times has your malfunction occurred on an aircraft fuel system?
bgwalter•4h ago
Not precisely the electrical malfunction, but dual engine shutdown has occurred, fortunately after landing:

https://www.aerosociety.com/news/ana-787-engine-shutdown/

cosmicgadget•4h ago
That doesn't seem to be a malfunction at all.
stefan_•4h ago
And then 10s later the switches magically fixed themselves? The likely not electronically connected switches since that would compromise engine redundancy?
lazide•4h ago
The other pilot likely flipped them back - but at that point, it was impossible to avoid crashing.
dcreater•3h ago
intermittent state switching is absolutely a thing in (poorly designed/manufactured/tested/QC'd) electronics
pixl97•3h ago
It is, and one would expect that a single switch failure would be far more probable, so how often have we had switch failure single engine cutoff in the 787?
userbinator•2h ago
All this rests on whether we have CVR audio of the pilot(s) manipulating the switches.
ekianjo•40m ago
The rodents were remorseful and fixed the cables in the meantime. /s
K0balt•4h ago
The time between the two switches being activated and then them being switched back on after being noticed strongly suggests that they were actually manipulated. Malice looke very likely to me. An investigation into the pilots life may turn something up, I guess.

It’s worth noting that Premeditation or “intention” doesn’t have to factor into this.

Studies of survivors of impulse suicides (jumping off of bridges etc) indicate that many of them report having no previous suicidal ideation, no intention or plan to commit suicide, and in many cases no reported depression or difficulties that might encourage suicide.

Dark impulses exist and they don’t always get caught in time by the supervisory conscious process. Most people have experienced this in its more innocuous forms, the call of the void and whatnot, but many have also been witness to thoughtless destructive acts that defy reason and leave the perpetrator confused and in denial.

dcreater•2h ago
> The time between the two switches being activated and then them being switched back on after being noticed strongly suggests that they were actually manipulated

How so? It is just as likely to be an intermitted electronic malfunction.

pixl97•2h ago
For both switches on seperate systems and wires that are independant.

I mean, it's not impossible, but it sure the hell is improbable.

postingawayonhn•4h ago
There is also audio of the pilots discussing the issue.
__turbobrew__•5h ago
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.
pigbearpig•5h ago
There are pictures of them in the report.
ls-a•3h ago
So you're telling me that those switches don't have a voice that says "fuel cutoff switches transitioned" like in the movies? That's bad design
Waterluvian•3h ago
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.
yardstick•2h ago
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.
userbinator•3h ago
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

Or more precisely, the signals which come from them were found to behave as such.

Without any audible record of turning the switches off, I wouldn't blame the pilots without first checking the wiring and switches themselves for faults. This reminds me of the glitches caused by tin whiskers.

crtified•2h ago
I agree, there's a significant distinction between "the switches were (physically) flipped" and "the circuit was opened/closed".

In this case, it may be a moot distinction, particularly if no physical evidence of fault or tampering has been discovered in investigation. But, in theory, very important - there's a lot of potential grey-area between the two statements.

The proximity of the incident to the ground may also increase the possible attack vectors for simple remote triggers.

usefulcat•2h ago
If that was the case, it does seem a bit odd that there was a one second gap. But yeah, still worth investigating, if that’s even possible given the extensive damage.
Epa095•2h ago
But from the audio recording it seems like one pilot is noticing them bering in the CUTOFF position, and asking why (and moving it back). If the switch was actually in RUN, but some other issue caused the signal to be sendt, the pilot would see it beeing in the RUN position, not CUTTOF.
groos•1h ago
Suicide is quite a stretch without any supporting evidence from the pilots' backgrounds. I would take mental fog, cognitive overload, wrong muscle memory, even a defective fuel cutoff system over suicide.
prepend•1h ago
I once worked with a software engineer who would do things and then bald face lie about it. This reminds me of that person.

Me: “The build is breaking right after you checked in. Why did you do that?” Him:”I did not do so.” Me: “The commit shows it as you. And when I rolled back everything builds.” Him:”It must have been someone else.”

That person was really annoying.

WalterBright•1h ago
> It's difficult to conclude anything other than murder-suicide.

Remember that incident where a cop pulled out his taser and tased the suspect? Except he pulled out his pistol and fired it.

The taser looks nothing like a pistol, feels nothing like it, yet it is still possible to confuse the two in the heat of the moment.

throwawaycan•12m ago
It’s always easy in those threads to see who’s familiar with the world of aviation and who’s not.

No it’s not comparable to a cop that confuses things in the heat of the moment. Not anywhere close to be relatable.

If it was, planes would be crashing down the sky quite often (and it would have been fixed for decades already).

YetAnotherNick•1h ago
Reminds me of 2017 Las Vegas shooting. The perpetrator looked and acted completely normal till the day of shooting and all his issues like anxiety or losing money was nothing far from ordinary. And what seems all of a sudden did a well planned shooting and didn't bother to leave a note or tell his story.
refulgentis•1h ago
Free memento mori: you're both free-associating.

There's 0 reason to conclude murder-suicide, there's an infinitude of things that could have the same result, and both pilots denied it to eachother: how is that presented as proof?

I hope I don't need to explain why the fact no one knew in advance the Las Vegas shooter was going to shoot has ~0 similarities with the situation as we know it, and banal similarities with every murder.

bob1029•6h ago
> The EGT was observed to be rising for both engines indicating relight. Engine 1’s core deceleration stopped, reversed and started to progress to recovery. Engine 2 was able to relight but could not arrest core speed deceleration and re-introduced fuel repeatedly to increase core speed acceleration and recovery.

I know it's probably not worth the hazmat tradeoff for such a rare event, but the F-16 has an EPU powered by hydrazine that can spool up in about a second.

ceejayoz•6h ago
I suspect any civil aviation engineer who goes "let's add hydrazine!" to fix problems has a fairly short career, lol.
lazide•4h ago
Yeah, now you have at least two problems.
SJC_Hacker•1h ago
The only solution I can think of is emergency parachutes. Like lots of them. would also be useful for other types of in air engine/control failures.

At least it worked for me on Kerbal Space Program. At least sometimes.

maxbond•1h ago
There's precedent.

https://www.youtube.com/watch?v=2_8qCTAjsDg [30s]

https://www.youtube.com/watch?v=zT58pzY41wA [15m]

The Cirrus system is deployed by rockets, allowing it to function at a very low altitude. They say that you should deploy it no matter what altitude you are at, and it will add at least some friction. The system has a very impressive track record.

However, at this altitude, with an airplane this heavy, you might have to put the rockets on the plane to decelerate enough to save lives.

ChrisArchitect•5h ago
More discussion: https://news.ycombinator.com/item?id=44536691
cosmicgadget•5h ago
The report says the co-pilot was flying so it's most likely the pilot cut the fuel?
sillysaurusx•5h ago
Correct. Which means it’s the older of the two.
janice1999•4h ago
The report does not identify which pilot said what. Attempting to extrapolate their identities is speculation.
cosmicgadget•4h ago
The report specifically says the FO was flying. The conversation is immaterial since the person who cut the fuel could have made either statement.
fsckboy•4h ago
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 youtube pilot/analysts I watch but dismissed as unlikely.
codefeenix•4h ago
even though that raising the gear is a up motion and fuelcut off is a down motion?
rogerrogerr•4h ago
And fuel cutoff is _two_ down motions? That's the death knell for this theory, imo.
fsckboy•3h ago
i have several passwords i type all the time. sometimes i get them confused and type the wrong one to the wrong prompt. i type them by muscle memory, but i also think about them while typing and i think thoughts like "time to reach up and to the left on the keyboard for this password". I couldn't tell you the letter i'm trying to type, i just know to do that.

not all my passwords are up and to the left, some are down and to the right, but when i type the wrong one into the wrong place, i type it accurately, i'm just not supposed to be typing it.

"time to do that thing i've practiced, reach to the left". shuts two engines off by muscle memory.

WalterBright•47m ago
My editor is MicroEmacs, which I've been using since the 1980s. I no longer remember what the commands are, but my fingers do.

I remember once writing a cheat sheet for the commands by looking at what my fingers were doing.

zarzavat•3h ago
Would anyone be surprised if an accomplished concert pianist played C Bb Bb instead of C E in a piece they had played thousands of times correctly?

The only difference here is that the consequences are death instead of mere head shaking.

Murder needs more proof than just performing the wrong action. Until then we should apply Hanlon's Razor.

dyauspitr•3h ago
Sometimes I drive all the way home without being aware of what I did in between.
adrianmonk•1h ago
I don't think the theory is that the muscle memory sequences resemble each other.

Instead, it's that because muscle memory allows you to do things without thinking about it, you can get mixed up about which action you meant to perform and go through the whole process without realizing it.

mcpeepants•51m ago
Is actuating the fuel cutoff switches something that is done routinely in these aircraft, to the extent it could reasonably become muscle memory?

ETA: downthread it is mentioned that these switches are used on the ground to cut the engines

fsckboy•4h ago
that makes it less likely, not impossible, we're trying to match against the data we have. I think distracted muscle memory is more likely than suicide and sounding innocent while lying about it
russdill•3h ago
There is no possible way to confuse these two actions. There's a reason a wheel is attached to the gear lever.
chmod775•3h ago
Sometimes people put cleaning liquid in the fridge.

Given a long enough span of time, every possible fuck up eventually will happen.

dboreham•2h ago
Probably time to design a plane that can't be sent into terrain in seconds by flipping a switch.
zamadatix•2h ago
"Sent into terrain in seconds by flipping a switch" is both too inaccurate and feels too cursory to take as impetus for serious design criticism, especially when the extensive preliminary report explicitly does not recommend any design changes with the current information.
sxg•2h ago
Now try to design a plane that also lets you rapidly shutoff fuel to both engines in case of fire.
cjbprime•3h ago
> 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.

resize2996•2h ago
you probably shouldn't be a pilot, bub
sxg•2h ago
Studying how humans make errors is a fascinating field. Simply banning someone who's made a "slip" error as hypothesized wouldn't actually reduce the likelihood of this error occurring in the future. These sorts of errors are stochastic and could happen to anyone at any time. Preventing them requires a lot of thought.
bigDinosaur•1h ago
If someone confused their steering wheel for the brake you'd probably be surprised - there are indeed errors that are essentially impossible for a competent person to make by mistake. No idea about the plane controls, though.
energy123•1h ago
I want you to guess how many traffic accidents are caused by accidentally reversing when you intended to go forward.

Test your mental model against the real world. This is your opportunity.

zamadatix•3h ago
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 comments on this post remind me it'll just be a brand new set of random guesses until the final report is released. Or worse - the final report reaches no further conclusions and it just has to fade out of interest naturally over time.

747fulloftapes•3h ago
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 behind the throttle stalks above the handles to release the engine fire suppression agents. These switches are markedly smaller and have guards on each side protecting them from accidental manipulation. You need to reach behind and twirl your fingers around a bit to reach them. Actuating these switches requires pulling the knob up sufficiently to clear a stop lock before then rotating down. There are two switches that were activated in sequence and in short order.

The pilot monitoring is responsible for raising the gear in response to the pilot flyings' instruction.

I would find it very difficult to believe this was a muscle memory mistake. At the very least, I would want to more evidence supporting such a proposition.

This idea strikes me as even more unlikely than someone shifting their moving vehicle into reverse while intending to activate the window wipers.

macintux•1h ago
> 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.

dyauspitr•3h ago
If you shut off the engines a couple of dozen meters above ground shouldn’t every alarm be blaring or there should be some sort of additional lever you have to pull way out of the way to enable shutting off the engine that close to the ground.
WalterBright•49m ago
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.

celsoazevedo•4h ago
Report mirror as the site seems to be down:

https://celsoazevedo.com/files/2025/Preliminary_Report_VT_AN...

comrade1234•4h ago
Why can the pilot shut off the fuel during takeoff?
jeffbee•3h ago
Suggest a system that would prevent this, but only this, without causing other risks.
bob1029•3h ago
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 if you are heading into terrain.

dboreham•2h ago
Sounds good, but I'm not sure I trust Boeing outsourced software developers to implement that absolutely correctly.
yongjik•2h ago
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.
baseballdork•3h ago
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.
dboreham•2h ago
I can't put my car into reverse gear while driving down the freeway.
stetrain•2h ago
There’s no good reason to do that.

There may be a good reason to cut fuel to one engine shortly after takeoff.

You could have a system that prevents both switches being thrown, and only in the specific window after takeoff, but you’ve also now added two additional things that can fail.

arp242•2h ago
You also can't reverse a plane while flying it...

This is a rather odd comparison. You can slam the brakes, yank the steering week, and do all sorts of things to intentionally make the car crash.

sgentle•1h ago
Sure, but you can open the door, pull the handbrake, or turn the wheel so hard you lose control of the vehicle. These are all similarly preventable, but maybe not worth the risk of being unable to open the door, brake or steer if the safety mechanism fails closed, or if your situation is outside the foresight of its designer.

Also, you don't need multiple certifications and 1500 hours of experience to drive a car.

berti•1h ago
You can turn the ignition off. The reversers will not unlock on an airliner that's airborne either.
WalterBright•44m ago
Remember the "surging" incidents where the driver insisted he was stepping on the brake but was actually stepping on the gas?
testing22321•15m ago
A friend did exactly that in a manual transmission, doing 100km/h.

She was mad and said she has to jam it hard ( going for 5th and missed), but it went into reverse. And the gearbox literally hit the road when she let out the clutch.

rhcom2•3h ago
Completely uneducated guess but if one engine bursts into flames you might want to kill the fuel.
lysace•3h ago
What you are really asking is: would we, the passengers, be safer without human pilots?

Eventually, yes. Soon? Maybe.

bigtones•3h ago
Each of the fuel switches on the 787 is equipped with a locking mechanism that is supposed to prevent accidental movement, experts said. To turn the fuel supply on, the switch must be pulled outward and then moved to a “RUN” position, where it is released and settles back into a locked position. To turn the fuel supply off, the switch must be pulled outward again, moved to the “CUTOFF” position and then released again.

https://www.nytimes.com/2025/07/11/world/asia/air-india-cras...

apt-apt-apt-apt•3h ago
Even if the plane had no power, why couldn't they have glided it down safely?
detaro•3h ago
how do you "safely" glide into a city?
russfink•2h ago
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.
stetrain•2h ago
It did glide briefly, the glide path took it directly into a school building.

Right after takeoff at low altitude is basically the worst place for this to happen. Speed and altitude are low so gliding is going to be a short distance and happen quickly.

If there had been a perfect empty long flat grass field in that location it may have been salvageable, but also right after takeoff the plane usually has a heavy fuel load which makes for a much riskier landing.

Edit: This article has a map showing the glide path:

https://www.theguardian.com/world/2025/jun/12/air-india-flig...

appreciatorBus•2h ago
They only ever got a few hundred feet off the ground.

Yes of course the plane glided once the engines stopped, producing thrust, just like all planes do. But just like all planes, and all gliders, gliding means trading altitude for velocity - giving up precious height every second in order to maintain flight. At that stage in the flight, they just didn’t have enough to give. If the same thing had happened at 30,000 feet, it would be a non-event. They would glide down a few thousand feet as the engines spool back up and once they return to full power, everything will be back to normal. Or if for some reason, the engines were permanently cooked, you’d have maybe 20 to 30 minutes of glide time so you’ve got a lot of time to look around and find a flat spot. But you just don’t have enough time for all that to happen When you’re a few hundred feet off the ground.

WalterBright•38m ago
Speed can be traded for altitude, and altitude can be traded for speed. If you have neither, you're dead.

Engine failure shortly after takeoff is a major cause of fatal accidents.

1970-01-01•3h ago
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.
WalterBright•42m ago
Fire isn't the only instantly severe problem with engines. Another is violent shaking if, say, part of the rotating assembly came off.
xyst•2h ago
A simple wrong flip of a switch killed 260 people and leaving 1 lone survivor who walked away from the plane crash nearly unscathed.

Dudes is extremely lucky or the character from Unbreakable.

stetrain•2h ago
A flip of two switches, in sequence, with a locking mechanism on each switch.
resist_futility•2h ago
In this YouTube short you can see the pilot switching both fuel cutoff to run

https://www.youtube.com/shorts/bd4Bler36Nk

deadbabe•1h ago
there's literally two other similar switches right next to those?
resist_futility•1h ago
The switches on the lower panel that are switched, are the fuel cutoffs
Anishx7•1h ago
reached v1, then when airborn fuel cut off. Seems like there was a FAA report like in 2018 that recommended few airplane models (incl this one) to check the fuel valves correctly, seems like air india didn't do it. Turns out it was made by Honeywell
jeswin•34m ago
I know that the switch had to be operated deliberately, but still a UX fail on a modern aircraft if cutting off fuel to the engines does not result in an audible alert/alarm which both pilots can hear - especially at that altitude.