Boeing 787-8 Dreamliner just crushed in India right after take off. Again Boeing.

[unicorn]

https://www.cnn.com/2025/07/11/india/air-india-crash-report-intl-latam

"A cut in the fuel supply to the engines caused last month’s Air India crash that killed 260 people, a preliminary report has found. The London-bound plane had barely left the runway at Ahmedabad airport when it hurtled back to earth. Everyone on board was killed, except for one passenger. According to the report by India’s Aircraft Accident Investigation Bureau, obtained by CNN, the fuel control switches in the cockpit of the Boeing 787 Dreamliner had been flipped, starving the engines of fuel.

Investigators were able to get data out of the plane’s “black box” recorders, including 49 hours of flight data and two hours of cockpit audio, including from the crash. The aircraft had reached an airspeed of 180 knots when both engines’ fuel cutoff switches were “transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec,” according to the report. “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,” the report reads. Shortly after, the switches were reversed back to where they should have been, and the engines were in the process of powering back up when the crash happened..."

We may never know, but this could have been a deliberate murder-suicide à la German suicidal pilot.

[PeterRS]

9 minutes ago, unicorn said:

We may never know, but this could have been a deliberate murder-suicide à la German suicidal pilot.

Indeed, we may never know, but somehow I suspect this is not similar to the German Wings crash. Although we do not know the mental state of the two Air India piots, we did learn following the German WIngs crash that the co-pilot had quite serious mental problems which included thoughts of suicide. He had earlier been hospitalised for depression.

When searching his apartment a few days after the crash investigators found a doctor's letter declaring the co-pilot was unfit for work. As a result of doctor/patient confidentiality in Germany, the doctor could not pass any medical information on to the airline. 

Investigators also found he was taking two anti-depressants, escitalopram and mirtazapine, and a sleep medication. All were found in his body. Apparently escitalopram is associated with suicidal thoughts, especially soon after treatment is commenced. He had been prescribed this drug nine days earlier. Criminal investigators then discovered on his computer "ways to commit suicode" and "cockpit doors and their security provisions." As if this was not enough, doctors were aware that for years he had feared he was going blind. He had consulted no less than 40 doctors and feared his pilot's licence could be revoked. He should never have been in a cockpit, but German Wings did not know that in advance.

[Travelingguy]

In many ways, the preliminary findings are reassuring with regard to a safety problem with the 787.  This seems most likely to be a mass murder suicide, or less likely an accident.

The German Wings pilot flew into a mountain and killed everyone.  But when you are learning to fly, you learn very quickly that a crash on take off is usually a fatal event.  Whereas crashes on landing, especially in small planes, tend to have lots of damage to the plane, but fewer fatalities.  They teach you this, because everyone is so afraid of landing with the ground coming up to meet you.  But the take off is more dangerous and you need to respect the take off, be on your game and following your checklists and have a plan if you lose an engine.

[PeterRS]

1 hour ago, Travelingguy said:

In many ways, the preliminary findings are reassuring with regard to a safety problem with the 787.  This seems most likely to be a mass murder suicide, or less likely an accident.

 . . . But the take off is more dangerous and you need to respect the take off, be on your game and following your checklists and have a plan if you lose an engine.

Sorry but I do not agree with the murder/suicide theory for the very reasons i outlined in my earlier post. The co-pilot of the German Wings plane had a long history of psychiatric problems, had ingested a cocktail of drugs no active pilot should be taking, and had previousy researched suicide and how to lock cockpit doors tightly. Presently we have no reason to believe that either of the Indian cockpit crew had suicide on their minds.

The key question surely is: why did both fuel switches turn to off within a second of each other? I accept one pilot could have done it but as the co-pilot was flying the plane, it would have to have been the senior pilot who activated the switches. Both pilots denied responsibility just prior to the crash. The captain had logged 8,596 hours on the 787. It is impossble to believe that he had accidentally turned both switches off - each action itself requiring two actions. But for the time being it must remain one possible theory.

My primary concern is much more all the very major problems the 787 has experienced in the production plant in North Charleston, a totally new facility for Boeing plane manufacture. Books and endess articles have been written about this and whistleblowers have added to Boeing's problems. One whistleblower died the day before he was due to give testimony to Congress! All of which may mean nothing. But then the 787 problems keep cropping up, many just this year. The Dreamliners have been grounded several times, once when Boeing itself grounded 8 of them after discovering structural problems. More recently KLM has grounded 7 of their 787s, 30% of its long haul fleet. British Airways grounded 4 of its 787s for months, and has announced it expects to experience regular 787 groundings this year. 

Sam Selehpour, one of the whistleblowers, went public on the NBS Nightly News claiming there are small unplugged gaps in the welding of sections of the fuselge that could result in the plane literally coming apart. in mid-air.  Boeing has warned several airlines of design problems with the rear fuselage. Just this year, all airlines were ordered to ground their 787s for inspections. This is a plane that clearly seems feted to suffer major flaws. Could a computer malfunction - or indeed an unknown function as on the 737 Max crashes - be to blame? Eventually we will find out.

I often refer to the professional pilots website pprune.org but it is based in the USA and has not yet caught up with the AAIB findings.

[unicorn]

1 hour ago, PeterRS said:

Sorry but I do not agree with the murder/suicide theory for the very reasons i outlined in my earlier post. The co-pilot of the German Wings plane had a long history of psychiatric problems, had ingested a cocktail of drugs no active pilot should be taking, and had previousy researched suicide and how to lock cockpit doors tightly. Presently we have no reason to believe that either of the Indian cockpit crew had suicide on their minds...

Well, I doubt the evidence will ever be is iron-clad as the German Wings case, in which the evidence of murder-suicide was overwhelming. That being said, two fuel cut-off switches were flipped over, one right after the other. The other pilot became alarmed and switched them back, but too late. Any theory as to the ultimate cause has to take those facts into account. I suspect that the pilots' recent events/activities will now be researched. Murder-suicide was also postulated in that infamous Malaysian Airlines disappearance. 

Also from the CNN article: "...On the 787, the fuel cutoff switches are between the two pilots’ seats, immediately behind the plane’s throttle levers. They are protected on the sides by a metal bar and have a locking mechanism designed to prevent accidental cutoff...". So it's hard to imagine that the flipping of both fuel cut-off switches was accidental. 

[PeterRS]

3 hours ago, unicorn said:

1. Well, I doubt the evidence will ever be is iron-clad as the German Wings case . . .

2. I suspect that the pilots' recent events/activities will now be researched. Murder-suicide was also postulated in that infamous Malaysian Airlines disappearance . . .

3. it's hard to imagine that the flipping of both fuel cut-off switches was accidental. 

1. Totally agree.

2. I think when it comes to the possibility of murder/suicide, both the German Wings crash and the disappearance of Malaysian 370 have a major difference: both occurred well into the fight, between 30 and 40 minutes well after the aircraft had reached initial cruising altitudes. We still have little clue about the MH dsappearance, but the co-pilot could have downed the German Wings flight at any time on the outward sector from Dusseldorf or on the return - provided the captain was not in the cockpit. He waited until over the Alps and - I suspect - the authorities might have believed it was a result of a technical malfunction. He might have thought crashing into a mountainside at full speed would destroy the black box and the VCR. Without them, they would have little clue about his computer inputs or the attempt by the captain to reenter the cockpit. Pure speculation, I fully admit.  

3.The key difference for me betwen the AI crash and the other two is that it took place only seconds after take-off. If we assume for the sake of discussion that the captain was suicidal and intended to down the plane, why activate the fuel switches so close to the ground? As a highly experienced pilot, he will have known that investigators can find out vastly more about a crash when it happens on the ground rather than after spiralling down from 35,000 ft in the air or is out at sea. Bound for London, he knew he would have to fly over water - perhaps the Indian Ocean towards Dubai and then up over the Gulf, then just off the north coast of Turkey over the Black Sea or with a more northern route over the Caspian Sea, and finally on the descent over the English channel.

Remember Air France 447, the flight from Rio to Paris which crashed into the Atlantic in 2009 after the crew were completely mystified as to what was happening to the aircraft when the pitot tubes iced up? The investigation found that this was in part a result of crew failure, but it took two years to locate the flight recorders and for the exact cause of the crash to be known. For a long time it was assumed the black boxes would never be found. For a country like India where family is so important, surely it would be a monstrous disgrace and loss of face if known that one of their number had deliberately crashed a plane? Better to do it where the one whose actions caused it are less likely to be discovered? Again speculation.

4. Which then leaves one with the greater possiblity of a technical/computer malfunction. And here the BBC's website gives us another twist. It quotes from the Report that in December 2018, the US Federal Aviation Administration issued a Special Airworthiness Information Bulletin highighting that some Boeing 737 fuel control switches had been installed with the locking feature disengaged. It adds -

"While the issue was noted, it wasn't deemed an unsafe condition requiring an Airworthiness Directive (AD) - a legally enforceable regulation to correct unsafe conditions in a product.

"The same switch design is used in Boeing 787-8 aircraft, including Air India's VT-ANB which crashed. As the SAIB was advisory, Air India did not perform the recommended inspections."

And the technical issue theories do not end here. One former AAIB inspector wonders if the fuel switches tripped due to a problem with the plane's electronic control unit. Now we must sit and await further news.

Photo: BBC/Getty Images showing the fuel switches with their metal covers 

[PeterRS]

Just for info, I realise I added to my post above after @Moses gave it a like. 

[10tazione]

https://www.bbc.com/news/articles/cx2gy78gpnqo

[...]

It says in December 2018, the US Federal Aviation Administration issued a Special Airworthiness Information Bulletin (SAIB) highlighting that some Boeing 737 fuel control switches were installed with the locking feature disengaged.

While the issue was noted, it wasn't deemed an unsafe condition requiring an Airworthiness Directive (AD) - a legally enforceable regulation to correct unsafe conditions in a product.

The same switch design is used in Boeing 787-8 aircraft, including Air India's VT-ANB which crashed. As the SAIB was advisory, Air India did not perform the recommended inspections

[PeterRS]

2 hours ago, 10tazione said:

https://www.bbc.com/news/articles/cx2gy78gpnqo

[...]

It says in December 2018, the US Federal Aviation Administration issued a Special Airworthiness Information Bulletin (SAIB) highlighting that some Boeing 737 fuel control switches were installed with the locking feature disengaged.

While the issue was noted, it wasn't deemed an unsafe condition requiring an Airworthiness Directive (AD) - a legally enforceable regulation to correct unsafe conditions in a product.

The same switch design is used in Boeing 787-8 aircraft, including Air India's VT-ANB which crashed. As the SAIB was advisory, Air India did not perform the recommended inspections

FYI I think that is exactly what I wrote at the end of my earlier post - the same BBC quote although I had omitted the BBC link, so thank you for that.

[unicorn]

Most analysts now agree that it was something that one of the pilots did. Whether it was serious negligence or deliberate (murder-suicide) is not known, and may never be known. 

[PeterRS]

Looking at the photo in my earlier post, it is clear that the fuel cut off switches are very close to the engine throttles. As we know each fuel cut off switch requires two separate actions -a pull out locking device and then a move down.  We know from the USFAA SAIB notice in 2018 that some 737s had been delivered with the locking device disengaged. The advisory note provided to airlines was simply that: note it and take action. But it was not mandatory. The switch designs on the 787 are identical to those on the 737 and it is not known if the locking device was in fact operational on the doomed 787. If not, then even accidentally brushing the switches with simple hand movements would be enough to activate the cut off.

To me that seems simple. But it fails to take into account that there is no record of such accidental touches had happened on take-off before. It also assumes the cut off switch was in fact disengaged. Additionally, when taking off, for full power the thrust levers are pushed forwards, not backwards. Accidentally touching the fuel supply switches would be extremely unlikely.

But then there is concern that the aircraft was fitted with a computerised autothrottle device. To my understanding, this means pilots input the desired flight parameters including engine thrust. The computer then ensures that thrust management provides optimal engine thrust under varying flight conditions. Thus at take-off, the computer effectively takes control ensuring that the pilot flying does not require his hands on the thrust levers shortly after the aircraft leaves the ground. What a hand does thereafter is up to the pilot flying.

It is known that this autothrottle computer programme caused issues with the 787 fleet on October 23 2024 when the FAA issued a mandatory Airworthiness Directive for all 787s. This gave airlines 6 months to correct safety concerns related to "erroneous autothrottle behaviour". The Directive continues -  

"The directive was prompted by incidents where the autothrottle system exhibited erroneous behavior during critical flight phases such as balked landings, with the system failing to properly adjust thrust levels. Additionally, the low range radio altimeter (LRRA) has shown potential for erroneous readings, which can lead to inadequate airspeed protections. These issues could result in unsafe conditions, including runway overruns or controlled flight into terrain."

We have no idea if Air India had acted on the Directive. Even so, we also do not know if such an action would automatically push the autothrottle switches downwards.   

There is also the fact that on the flight from Delhi to Ahmadabad this 787 was beset by several internal electrical problems. Passengers sat on the ground with the doors shut for more than 15 minutes with no air conditioning despite intense heat. The in-flight entertaiment system did not work. Passenger lighting and the crew call buttons did not work. As the passenger who took the video said "Nothing is working!" Often on the ground, the a/c will be supplied by an external power unit. But that is disconnected around five minutes prior to push-back when the engines are started. Even then, as this aircraft was taxiing the on board a/c was still not working. Was there perhaps a greater electrical problem that came to affect the aircraft on the second leg of the flight to London. More speculation.

https://www.aviacionline.com/faa-issues-airworthiness-directive-for-boeing-787-dreamliners-due-to-autothrottle-and-radio-altimeter-issues 

 

[unicorn]

Captain Steeeve feels convinced that the switching of the fuel cutoff switches must have been intentional and neither due to accident nor negligence:

 

[PeterRS]

9 hours ago, unicorn said:

Captain Steeeve feels convinced that the switching of the fuel cutoff switches must have been intentional and neither due to accident nor negligence:

I have watched several of this captain's videos and have basically agreed with almost every part of his various analyses. The one second gap between the fuel control switches being turned off is certainly an issue that needs very close investigation. If, as my earlier posts have considered, there was a major technical malfunction, the assumption would have to be that both switches turned to the off position at precisely the same time. But we should recall he states that in the history of aviation there is no procedure where immediately after "rotate" you grab both conrol switches and place them to cut off. It therefore had to be intentional.

Probably beause he was not aware of it, there is a very roughly similar example of power being cut from engines (along with other wrongly activated pilot procedures) which @Keithambrose mentioned early in this thread. In June 1972, a Britsh European Airways Trident aircraft crashed soon after take off. At 16:09:10 the aircraft left the runway at London's Heathrow en route to Brussels. As the aircraft climbed, due to a severe loss of power the Trident entered a deep stall and crashed into the ground at 16:11:00. In this case the crew had overridden the standard stall warnings.

There were, as noted, several reasons which caused that crash which included the state of health of the captain, failure to monitor speed, specific actions which led to early retraction of the flaps and others largely involving the crew. It can not be identical to the AI crash if only because the cockpit layouts and computerisation more than 50 years ago were vastly different. But there are certainly some rough similarites - notably a loss of engine power. 

The only other concern I have about the Report is that it took 12 seconds from discovery that the fuel supply had been cut off for the switches to be reactivated. Granted there will have been massive confusion in the cockpit. But one of the pilots in the vdo states that the other pilot saw out of the corner of his eye that his colleague had swtiched the fuel supply switches to off and asks whey he did that. That being the case, why - despite all the confusion - why did it take the one who made that comment a full 12 seconds to switch fuel supply to one engine back on followed two seconds later by the second fuel supply switch? If you know you have lost power because the fuel supply switches are in the wrong position, is not your primary reaction at that utterly critical stage in the flight to do everything possible to switch them back on? That in my view could surely not have taken more than 5 or 6 seconds.

[unicorn]

16 minutes ago, PeterRS said:

...The only other concern I have about the Report is that it took 12 seconds from discovery that the fuel supply had been cut off for the switches to be reactivated... That in my view could surely not have taken more than 5 or 6 seconds.

In hindsight, it shouldn't have taken that long, but as the captain explained, it's not as if alarms would have gone off immediately. He asked "Why did you switch the fuel cut-off levers?", then the other replied "I didn't switch the fuel cut-off." Then a few seconds to realize what was going on. Or maybe the suicidal pilot kind off fought him off. We now have a good feeling of what happened, but at the time it probably wasn't immediately obvious. 

[PeterRS]

3 hours ago, unicorn said:

In hindsight, it shouldn't have taken that long, but as the captain explained, it's not as if alarms would have gone off immediately. He asked "Why did you switch the fuel cut-off levers?", then the other replied "I didn't switch the fuel cut-off." Then a few seconds to realize what was going on. Or maybe the suicidal pilot kind off fought him off. We now have a good feeling of what happened, but at the time it probably wasn't immediately obvious. 

Yes, that all makes sense. But it again assumes one pilot intent on suicide, something that has very rarely happened in the history of flight - as rare as fuel supply switches cutting off unexpectedly. Had it been the captain switching off the levers intentionally, I can understand that he could have made sure his hand stayed on the control switches thereby making reactivation by the copilot much more difficult, the more so as the copilot was still busy flying the aircraft. If the copilot - whose left hand would have been on the throttle levers and his right on the yoke - had switched them off, I suspect it ought to have taken the captain mere seconds to switch them back on without even the need to ask "Why did you do that?" Brain memory would surely have kicked in immediately. We also have no indication in the report of what the poilots may have been saying to each other both before and after the two sentences in the report. These may offer more clues. Also, the thrust levers were both found to be in the standard forward take-off position. If you are cutting the fuel, why keep the throttles in the maximum thrust position? Until we know about these and who asked the question, we'll not know the answer.

Apart from German Wings, the only other crash i know to have been attributed directly to pilot suicide was an Egyptian Air 767 on October 31 1999. Ths is described in amazing detail in a long article in The Atlantic by a former professional pilot. That 767 flight had originated in Los Angeles and had stopped in JFK to refuel, change crews and pick up new passengers. For the rest of the flight, there were two crews on board. Additionally Egypt Air's Chief 767 pilot and instructor had deadheaded - picked up a lift on the flight to get back to Cairo. Twenty minutes into the flight, the two crews swapped positions. In the co-pilot's seat now was the portly 60-year old Gameel al-Batouti. Generally too old for a co-pilot but his English was poor and having joined the airline much later than younger co-pilots he was perfectly happy being in the right cockpit seat. He was married and had five children. He and his wife had a vacation home on the beach. On the flight he had in his bag some boxes of viagra to hand out back in Egypt as gifts!

The flight lasted 31 minutes. By this time al-Batouti was in the co-pilot's seat. He was an old friend of the captain who called him by his nickname "Jimmy". As occurred on the German Wings flight, the captain decided to take a toilet break. The 767 was cruising at 33.000 ft and al-Batouti was alone in the cockpit. Softly al-Batouti can be heard on the CVR saying "I rely on God." The autopilot was then disengaged. Four seoonds later, al-Batouti repeated "I rely on God", a phrase he was to continue uttering during the next horrifying minutes aways in a calm tone. Almost simultaneously the throttles were pulled back to minimum idle and the horizontal stabiliser dropped to a 3-degree down position. The 767 was now starting a deadly dive. 

The captain had quickly made his way back into the cockpit. Three times he is heard asking "What is happening?" Probably unable to reach his seat due to the G-forces, he leant over and desperately tried to use his control to pull up the nose. The aircraft was now falling at the speed of sound. al_Batouti reached over and cut the fuel supply switches. During all this time all manner of alarms were going off including a master alarm.

As a result perhaps of the captain's efforts, the aircraft gained altitude. But with no power, at 24,000 feet and with its rate of velocity, the aircraft began to break apart. It took 114 seconds for what was left of it to crash down into the Atlantic Ocean. Soon the US media had begun to get hold of the flight's final details and blamed suicide. The NTSB, aware of the cultural impact between two nations, was less direct. Cairo was furious and spent the next two years trying to find ways to absolve al-Batouti of any guilt.

In New York, it was soon discovered that al-Batouti was a bit of a playboy and mild sexual molester (although never rape or inded much more than groping). Worse, in the crew's hotel during the NYC layover, there had been a major bust up with the captain who, it has been allleged, had threated al-Batouti with disciplinary action once back in Cairo. In the end, neither country agreed on what exactly had happened. But the evidence held in the USA very clearly pointed to suicide causing the deaths of 217 passengers and crew. Unlike the German Wings crash, though, there seemed to be no clear reason for al-Batouti to take such devastating action. Yet again, though, he had crashed the aircraft when it was well into its flight. And this is one reason surely for at least wondering why, if the Air India crash was indeed a suicidal action, why whichever crew member switched off the fuel supply did so just as the aircraft was taking off rather than waiting until much later into the flight. That surely leaves some room for doubt.

https://www.theatlantic.com/magazine/archive/2001/11/the-crash-of-egyptair-990/302332/

[PeterRS]

On 7/12/2025 at 10:29 AM, Travelingguy said:

They teach you this, because everyone is so afraid of landing with the ground coming up to meet you.  But the take off is more dangerous and you need to respect the take off, be on your game and following your checklists and have a plan if you lose an engine.

Sorry but the degree of danger is not quite the view of professional pilots - and the statistics agree with them. According to Tom Ferrier, a retired US Air Force Commander, from 1959 to 2016 48% of all fatal accidents have occured on final approach or landing. By contrast, during take-off and the start of the climb the figure is only 13%. This 13% takes into account the difficulties pilots often faced in the earlier days between V1 and V2 - the times when an aircraft must take off and secondly can actually take off with one engine out. Since engine power was less, there were more take-off accidents in those days.

https://www.forbes.com/sites/quora/2017/10/25/when-flying-is-taking-off-really-more-dangerous-than-landing/

In my flying days I have been in four aborted landings, two for other aircraft on the runway and two for weather. The last was last year when flying from Taipei to BKK. A major monsoon storm was moving over BKK and the pilot tried to land twice, each time aborting. We ended up having to fly to Chiang Mai to refuel and finally get back to BKK four hours late.

On the other hand, I have only been on one aborted take-off. That was almost three decades ago on a Cathay Pacific flight from HKG to Beijing. Hurtling down the runway, we were suddenly thrust forward in our seats as the plane shuddered to a halt - thankfully missing hurtling into the sea at the end. The captain quickly came on the intercom and quite noncholantly said "My apologies ladies and gentlemen for that sudden halt. A red light suddenly lit up in the cockpit and I'd rather have it fixed on the ground than try to do so in the air!"

One new China Airlines 747-400 made a botch of the landing in the early-1990s and literally ended up in HKG harbour. No one was injured but the plane was a write-off.

[thaiophilus]

41 minutes ago, PeterRS said:

Sorry but the degree of danger is not quite the view of professional pilots - and the statistics agree with them. 

 

I think you're both right. @Travelingguy is talking about light aircraft, not airliners, and crashes, not necessarily fatalities. The detailed statistics are no doubt different but I don't think that's the issue. The point is that takeoff is a dangerous phase of flight because everything mechanical is under maximum stress, so undetected problems may make themselves known,  and when they do you have neither height nor speed in reserve to deal with them.

[PeterRS]

2 hours ago, thaiophilus said:

I think you're both right. @Travelingguy is talking about light aircraft, not airliners, and crashes, not necessarily fatalities.

Sorry for misreading that point. Frankly I am not a pilot and know little about actual flying. I was once a passenger on a small microlite plane in Thailand where we took off and landed from a field with some cows! But I loved that little flight.

The only time my travels have been affected by a small plane was at the small airport on the Argentine side of the Igazu Falls. I was boarding an Aerolineas Argentinas 737 to Buenos Aireas domestic airport before transerring to the international airport for a LAN Chile flight to Santiago.

Fortunately I had allowed lots of time for the transfer. Before boarding was complete, we were asked to deplane and wait in the small departure lounge. We had no idea why and it took about 10 minutes for one of the airline staff to explain. A small single seater aircraft had crash landed on the single runway. No flights could get in or out until the wreckage had been cleared. My ticket to Santiago was part of an 8-sector air miles ticket. So I had to make it or the computer would kill all my remaining bookings. I called the nearest air miles HQ which happened to be in Miami. If I missed the Santiago flight, the next flights I could get on would be about 3 weeks later! Had that not been possible I would have had to fork out thousands of $$. I started to panic! Needlessly as it turned out.

[young11]

It's daily mail but could be worth considering 

https://www.dailymail.co.uk/news/article-14902331/Air-India-crash-pilots-medical-records-examined-mental-health.html

[Travelingguy]

I am a pilot.  Small single engine only.

[floridarob]

6 hours ago, PeterRS said:

I started to panic! Needlessly as it turned out.

it's what you do 😁

[unicorn]

11 hours ago, PeterRS said:

..., if the Air India crash was indeed a suicidal action, why whichever crew member switched off the fuel supply did so just as the aircraft was taking off rather than waiting until much later into the flight...

When the fuel is cut at altitude, the plane doesn't simply drop like a lead cannonball. It's when the plane is taking off that the most fuel is needed, and immediately. The other pilot (they haven't said whether it was the captain or co-pilot) would have almost no time to react when the fuel is cut off during take-off. The 10-second delay is explained in this video. I suspect that the non-suicidal pilot simply didn't catch on immediately that the guilty pilot was intent on killing himself and everyone else on board. I don't think anyone else has used this method to commit murder and suicide. I don't understand why people who want to off themselves don't just blow their brains out or jump from a very high place. I suppose that in many jurisdictions, perhaps most, it's very difficult to buy a gun. I guess some nut-cases feel they need to go in a "spectacular" way, or want to make sure their name is remembered by as many people as possible. 😒