Preliminary report into Air India crash released

       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.

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.

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?

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.

> 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.

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

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

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.

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.

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.

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.

You can do them both with one hand.

Pilots unions are dead against it.

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...

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.

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.

This sounds to me like an electronics issue - an intermittent, inadvertent state transition likely due to some PCB component malfunction

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.

This implies intent.

> One pilot asked “why did you turn them off?” and the other said “I didn’t.”

To me this reads like an unintentional error with colossol implications.

Are you suggesting there was malicious intent and then a delibrately crafted denial by the perpetrator?

> This was not suicide, or murder-suicide; it was one of the most horrific mass murders in history, in which the guy that did it happened to lose his life in the process.

Why wouldn’t this qualify as a murder-suicide, assuming your theory is correct?

Pilots are drilled from day one that the fuel switches are sacred. After a few accidents where one engine failed and the pilot accidentally turned off the remaining functional engine, the training was overhauled so that it would be impossible for it to be an easy action done by mistake. One pilot is required to ask the other for confirmation before toggling the switch, I believe. It wouldn’t be something you’d do from muscle memory.

The report says the black box reports the fuel cutoff switches being activated. That doesn't necessarily mean that either of the two pilots activated them, it just means that the fly-by-wire system reacted to a fuel cutoff event.

"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 cutoff.

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."

It feels qualitatively different than someone pointing a gun at someone else and then themselves, which is usually what pops to mind when you hear “murder-suicide”.

You’re correct though, it qualifies.

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

It easy to say that when you know there's likely no way to prove or disprove whether it as an accident or not. Unless a pilot left a note stating his future intentions, there's no way to determine their state of mind.

If there was no mechanical failure, the only remaining possibility is deliberate action. And if it was mechanical failure, we’d see an emergency air worthiness directive being issued, which we haven’t.

It does:

1. Those switches have physical interlocks and cannot be manipulated by any computer system.

2. The flight data recorder is measuring the position of the switches; they aren't inferring the position from some system state. There's a "position of this switch" channel.

The switches were physically moved in the cockpit, that's basically ground truth. The question now is who and why.

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.

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.

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

If he was trying to do something else, he would have called it out. E.g. an audible “gear up.”

And, it's _two_ switches.

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?

https://simpleflying.com/boeing-787-technical-features-guide...

" Advanced electric controls

The 787 entered service with an improved fly-by-wire flight control system. Rather than mechanical processes, the systems convert flight deck crew inputs into electrical signals. Still, there were additional advancements with the type."

So I can't imagine how it could have been done accidentally.

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

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

Honestly I think the chances are good that you're right, but the way you're presenting it as absolutely certain strikes me as overconfident, borderline arrogant.

Also, what's with the whole "staking your reputation" thing? What reputation? Are you some kind of famous journalist? Is there some reason we should care about you "covering live news" ? Serious questions -- I personally have no idea who you are.

I'm also interested in the earlier switch defects where the switches were installed with the locking mechanism disengaged on some 737s and inspection was advised for 787, but the incident aircraft was not inspected.

The airworthiness directive for that [1] indicates switches with locking disengaged should be replaced, but I wonder if it's possible to reingage the locking somehow, which could result in a situation where the locking wasn't engaged, the switches changed inadverdently and then when restored the run position the lock was engaged... that's a big reach, of course.

All that said, assuming the switch was working as designed, there's a semantic argument around deliberate and intentional. If the switch requires specific action, it's fair to call it deliberate action; but if the switcher thought they were activating a different switch, it's not murder.

Either way, there's no sense rushing to a conclusion of murder. Assuming one of the pilots activated the switch, they have already died and they are beyond the effects of human judgement; so we may as well wait for further information.

[1] https://ad.easa.europa.eu/blob/NM-18-33.pdf/SIB_NM-18-33_1

I also don't recognize this guy's name, but I do find it ironic that his profile is possibly the most well-linked to a other identities I've ever seen on HN: https://news.ycombinator.com/user?id=sillysaurusx

https://www.cnn.com/2019/04/30/politics/boeing-sensor-737-ma...

787 (Dreamliner) was pushing hard for weight reduction, and it would not surprise me at all if the switch output fed a digital computer input rather than routing directly to the fuel shutoff valves, but I don't have any direct knowledge of this.

It’s mostly a very public "If I’m wrong, I won’t ever do this again." I’ve been writing informative HN comments since 2008 on various accounts. It’s a big deal to me not to spread misinformation or be mistaken in a situation like this.

The victims also deserve to be acknowledged. At this point the overwhelming body of evidence points to a deliberate act. Pilots are trained never to touch the fuel switches in flight, and (I believe) there is a verbal confirmation required before toggling. This captain had over 8,000 hours.

The reason I’m so confident is because I trust the system. It’s designed so that if either of the two pilots do anything, they verbally call it out, e.g. "gear up." A callout like that followed by fuel switch cutoff would indicate it was accidental. But as far as I know, there was no callout.

The pilot flying is also the one who asks for gear up and such. It’s the job do the pilot monitoring to perform those actions.

Suppose it was accidental. That would mean the pilot flying was fiddling with switches instead of flying; that’s against SOP. Or it would mean the pilot monitoring was performing uncommanded actions, which is also against SOP. It’s not something that happens on a whim. Both are contradictions, hence, no accident.

As for being overconfident or arrogant, what matters to me is accuracy, and passing along that accuracy. No one seemed to be willing to publicly call this a malicious action, so I did. If I’m wrong, you can be sure I’ll feel terrible for weeks, post an apology in the thread that shows I was wrong, and then bow out in disgrace, never to cover news again.

People here did the same thing when the common belief was that there was a non-zero chance of nuclear war. I was one of the few voices in that thread saying absolutely not, stop stressing yourself out for no reason.

I’m simply one voice of many. As always, it’s up to the reader to decide what to believe.

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.

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.

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.

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

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.

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

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.

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

In my view it would be quite hard to move them by accident, and probably not possible to move at once.

It would be interesting to know if the plane has any other switches of the same type, that are routinely activated.

The danger of a burning engine is irrelevant if you are heading into terrain.

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

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.

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

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.

Eventually, yes. Soon? Maybe.

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.

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.

Even taking intent for granted, to deny suicide in a case like this would be to suppose that the person responsible expected to survive while everyone else died. What could possibly support that conclusion?

Then why not either wait until there's more information or temper your remarks by acknowledging there's still ambiguity? That would directly hedge against spreading misinformation, whereas staking your reputation on it and then shutting up if you're wrong only works after the misinformation has spread and doesn't seem very productive.

I think the right response to realizing you've spread misinformation (in the event that you turn out to be mistaken [I think it's 60-40 in favor of deliberate]) is to temper your statements and rededicate yourself to checking the facts, not removing yourself from the discussion altogether. And if you were keeping your mouth shut, wouldn't you continue to see discussions you could meaningfully contribute to, and after a while wouldn't you wonder whether anyone was really benefitting from your silence?

Dudes is extremely lucky or the character from Unbreakable.

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.

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.

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

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...

I take your point that we should always be suspicious of complicated, digital buses, and this is not the final report, so there’s still plenty of time to uncover weirdness. However, if the flight date reporter shows the switch being thrown, and then a few milliseconds later, shows the valve starting to close, and the same sequence happening shortly there after on the second switch and valve, I feel this would really limit the likelihood of any digital shenanigans.

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.

It's quite possible it's a "performed the wrong muscle memory at the worst possible moment" type of accident. This is unlikely, but anyone who thinks such a mistake is impossible doesn't know anything about human factors.

Unlikely just means "low probability." There are thousands of flights per day, so it's only a matter of time.

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

The fact that your car's engine stops doesn't mean you turned the ignition switch off. Anyone who has had to troubleshoot a car with intermitent electrical faults knows that.

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.

I understand that you appear earnest. However, your history of multi-accounting on this site makes your promise to never post on a given topic again meaningless to me, because I have no expectation that you wouldn’t continue to post about it on other accounts that we don’t know about at this time, possibly because they haven’t even been created yet.

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

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.

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

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.

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.

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.

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

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

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.

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.

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.

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.

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

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?

Doing it accidentally is impossible.

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

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.

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

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.

I suspect you've never driven an older vehicle with the shifter on the steering column.

The switches physically moved, and there is no motor to actuate them without physical intervention.

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.

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

It's very hard to solve one problem without creating another. At some point, you just gotta trust the pilot.

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

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

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

I think you have to really reach to make this not pilot error. I know it’s appealing to call this a Boeing problem, but the evidence just from this prelim report is very compelling.

If you think it’s not pilot error, you can make some fake Manifold dollars: https://manifold.markets/JohnHughes/what-will-be-the-officia...

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.

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).

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.

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. See also ajb's comment below.]

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]

"The FAA issued Special Airworthiness Information Bulletin (SAIB ) No. NM -18-33 on December 17, 2018, regarding the potential disengagement ofthe fuel control switch locking feature. This SAIB was issued based on reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The airworthiness concern was not considered an unsafe condition that would warrant airworthiness directive (AD) by the FAA. The fuel control switch design , including the locking feature, is similar on various Boeing airplane models including part number 4TL837-3D which is fitted in B787-8 aircraft VT-ANB. As per the information from Air India, the suggested inspections were not carried out asthe SAIB was advisory and not mandatory. The scrutiny ofmaintenance records revealed that the throttle control module was replaced on VT-ANB in 2019 and 2023. However, the reason for the replacement was not linked to the fuel control switch. There has been no defect reported pertaining to the fuel control switch since 2023 on VT-ANB."

So while I agree that this being the cause sounds unlikely, referencing the switch issue is something relevant enough for the report itself.

You're leaping into the minds of others and drawing conclusions of their intent. One of them moved the levers. It could've been an unplanned reaction, a terrible mistake, or it could've been intentional. We may never know the intention even with a comprehensive and complete investigation. To claim otherwise is arrogance.

Will the bladder be marketed by Kramerica Industries?

The 787 and nearly every other commercial aircraft with powered flight controls [1] (fly-by-wire or traditional) has emergency power available via RAT and/or APU, and any fly-by-wire aircraft has batteries to keep the flight control computers running through engine failure to power supply being restored by the RAT and/or APU. Due to its unusually high use of electrical systems, the 787 has particularly large lithium batteries for these cases. There is no need for an additional EPU because the emergency systems already work fine (and did their jobs as expected in this case). You just can't recover from loss of nearly all engine thrust at that phase of takeoff. [2]

1. The notable exceptions to having a RAT for emergency flight controls are the 737 and 747 variants prior to the 747-8. In the 747 case, the four engines would provide sufficient hydraulic power while windmilling in flight and thus no additional RAT would be necessary. The 737 has complete mechanical reversion for critical flight controls, and so can be flown without power of any kind. There is sufficient battery power to keep backup instruments running for beyond the maximum glide time from altitude - at which point the aircraft will have "landed" one way or another.

2. There is only one exception of a certified passenger aircraft with a system for separate emergency thrust. Mexicana briefly operated a special version of the early 727 which would be fitted with rocket assist boosters for use on particularly hot days to ensure that single-engine-out climb performance met certification criteria. Mexicana operated out of particularly "hot and high" airports like Mexico City, which significantly degrade aircraft performance. On the worst summer days, the performance degradation would have been severe enough that the maximum allowable passenger/baggage/fuel load would have been uneconomical without the margin provided by the emergency rockets. I'm not aware of them ever being used on a "real" flight emergency outside of the testing process, and I think any similar design today would face a much higher bar to reach certification.

Edit: I recently saw an SF50 YT video. It's pretty awesome with the V/X tail.

That's very hard to do by panic and mistake, if not impossible by design.

Not within the context of the thread.

Fuel levers are designed to only be moved deliberately; they cannot be mistaken for something else by a professional pilot. It's literally their job to know where these buttons are, what they do, and when to (not) push them.

It's not arrogance to assume the most likely conclusion is true, despite how uncomfortable that outcome may be.

- 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 attendant holds onto his legs to keep him in the plane. The copilot and flight attendant think he is dead, but they keep the situation under control and land the plane.

Everyone survives - including the pilot.

https://www.youtube.com/watch?v=rGwHWNFdOvg

- United 232: An engine explodes in the tail of an MD-10. Due to rotten luck and weaknesses in the design, it takes out all three of the redundant hydraulic systems, rendering the control surfaces inoperable.

There's a pilot onboard as a passenger who, it just so happens, has read about similar incidents in other aircraft and trained for this scenario on his own initiative. He joins the other pilots in the cockpit and they figure out how to use the engines to establish rudimentary control.

They crash just short of the runway. 112 people die, but 184 people survive.

https://www.youtube.com/watch?v=pT7CgWvD-x4

- Pinnacle 3701: Two pilots mess around with an empty plane. They take it up to it's operational ceiling. While they're goofing off, they don't realize they're losing momentum. They try to correct too late and cannot land safely.

In their last moments they decide to sacrifice any chance they have to survive by not deploying their landing gear. They choose to glide for the maximum distance to avoid hitting houses, rather than maximizing how much impact is absorbed. They do hit a house but no one else is killed.

https://www.youtube.com/watch?v=DCMmCekKO_c

But I did burn out on Mentour Pilot after a while, I just had my fill of tragedy.

I do not trust these air worthiness directives 100.0%. The 737 Max also required two catastrophic failures before it was grounded.

The cost of hardware and additional fuel consumption due to drag aren’t nothing, but the data used itself is essentially a rounding error. (Iridium for example has tiny antennas, and SBD data costs about a dollar per kilobyte, and position data is tiny.)

Of course, that’s all little help when a pilot acts adversarial; on MH370, the breakers for both satcom and transponder were likely pulled, for example.

In safety-critical engineering, you generally either automate things fully (i.e. to exceed human capabilities in all situations, not just most), or you keep them manual. Half-measures of automation kill people.

You’re trying to prove a negative here.

I am not familiar with the 787 operations, but there are a few issues that need to be sorted out first: - altitude when pilots start the after takeoff checklist

- if there are any other switches that are operated in tandem in the general vicinity of where the engine cutoff switches are

- if the cutoff switches had the locking mechanisms present, and if not, if they could be moved inadvertently by the pilot flying hand

Discarding other possibilities in an investigation can have adverse consequences.

Did you ever always push the right buttons every time?

FAA issued a Special Airworthiness Information Bulletin SAIB NM-18-33 in 2018 warning that on several Boeing models including the 787 the locking mechanism of the fuel switches could be inoperative.

https://www.aviacionline.com/recommended-versus-mandatory-th...

Per FAA the checks were recommended but not mandatory.

This kind of attitude gets innocent people behind bars for life. Disgusting.

It's difficult to conclude anything until the investigation is finished and I hope the ones who are carrying it out are as levelheaded, neutral and professional as possible.

For instance, you might deliberately kill yourself by driving your car really fast into something solid, but you probably wouldn't try to do that while backing out of the garage.

However, the only relevant evidence that exists suggests they had enough rest. You don't build verdicts on suppositions, you build them on proven facts.

This does not guarantee you will reach the truth, but it's miles better than admitting every baseless hypothesis that comes up.

Hard to believe the other pilot wouldn’t have said anything.

Recovering the airplane and have some people survive the crash are two very different things.

> 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 don't know yet, and may never know; we only know what has definitely happened from the evidence per the investigation. It's standing way out over one's feet to declare from an armchair that it was "definitely" X or Y before the investigation is complete.

All the controls would be on a giant touchscreen, with the fuel switches behind a hamburger button (that responded poorly and erratically to touch gestures). Even a suicidal pilot wouldn't be able to activate it.

There's no handbrake to pull, and turning the wheel so hard to lose control is next to impossible. Maybe on an oily wet or loose surface.

Assumption. Big ass assumption.

Pilot are trained until actions are instinctual and certain memory items are almost unconscious. But pilots are still people and people are fallible and make mistakes, and sometimes act unreasonably. Intent cannot be determined without clear evidence or statements because that's now how thoughts locked away in people's minds work.

> It's not arrogance to assume the most likely conclusion is true

You don't know this. This is beyond the capability to know and is therefore pure speculation. That is the definition of arrogance.

Don't sentence people on unfinished investigations. This is why most trials are not public, because of people like you.

As a software engineer myself I think it's interesting that we feel software is the true solution when we wouldn't accept that solution ourselves. For example typically in a company you do code reviews and have a release gating process but also there's some exception process for quickly committing code or making adjustments when theres an outage or something. Could you imagine if the system said "hey we aren't detecting an outage, you sure about that? why don't you go take a walk and get a coffee, if you still think there's an outage in 15 minutes from now we will let you make that critical change".

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.

1: https://news.ycombinator.com/item?id=44539508

The workload is pretty high during the takeoff phase. The engines react right away when fuel flow is stopped. The engine displays can have some lag before data is updated.

Relighting an engine at low speed is not feasible - most need 230-250kts IAS before attempting the operation. Maybe you could do it if the APU was still running and could provide compressed air, but it takes about 20-30 seconds to start up amd then probably 5-10 more to spool up to full thrust. I am speculating here a bit, but the pilot did not have enough time to save the plane even if he did everyting right and as fast as humanly possible.

All this aside is overshadowed by the limited amount of time the pilot flying (I would assume the captain in this case since there was only one ATPL pilot in the cockpit) had to troubleshoot the issue of a dual engine failure - as this is what would have felt to him - during takeoff.

This comment stream on HN is not a jury. We don’t have to refrain from making judgments right now about what happened. There is nothing wrong with rational people reaching a preliminary conclusion based on available evidence.

Rational people should also remain open to revising their judgments/conclusions if new information becomes available.

And we shouldn’t demand any specific consequences for anyone absent a trial.