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Bluffontheriver123
2025-06-13T07:30:00 permalink Post: 11900107 |
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culzean12
2025-06-13T07:31:00 permalink Post: 11900108 |
The only thing that is clear from the footage is that the gear remains down. Which has led to the theory that the loss of lift is a result of the flaps being raised by mistake.
However a deployed RAT would be compelling evidence of dual engine failure or shutdown. Another explanation for the gear remaining down could be startle/distraction caused by engines rolling back at around rotate or liftoff. 2 users liked this post. |
FullWings
2025-06-13T07:36:00 permalink Post: 11900111 |
People on here seem convinced the RAT was deployed because they\x92ve seen it/heard it so many times before. They may be right. But if they are, then it means the RAT has deployed countless times before without both engines having failed, so it doesn\x92t definitively tell us anything.
System-wide electrical issues Double engine failure Selection of fuel switch and/or fire switch on both engines Any speculation about gear, flap, runway, etc. is redundant if the RAT did auto-deploy as it points to a very serious technical issue with the airframe rather than what was done with thrust levers or what the pilots had for breakfast. I haven\x92t seen what the 787 cockpit looks like on battery power only but on the 777 it gets pretty dark with only the essential P1 instruments and VHF1 available until the RAT comes online, which is a measurable amount of time after deployment is triggered. 2 users liked this post. |
TBL Warrior
2025-06-13T08:06:00 permalink Post: 11900137 |
![]() 6 users liked this post. |
Captain Biggles 101
2025-06-13T08:07:00 permalink Post: 11900140 |
There isn't enough clarity on numerous issues, and without answers to the following, zero conclusions can be made as to a possible cause. This is definitely one that could go in numerous directions. Anyone claiming to have the definitive answers must have the FDR data, and I'm assuming that shouldn't take too long to be located and analysed.
1a. Were flaps deployed at start of take off roll? 1b. Were flaps retracted coinciding with climb rate reduction? 2. Did the RAT definitely deploy? The videos are grainy low quality. AI improvement surely isn't reliable. 3. If the RAT deployed, would that indicate complete power loss? 4. Was there any other audio indicating thrust loss or variations during departure? 5. Can we confirm the pilot Mayday indicating thrust loss? If so, that needs investigation as a first priority. The pilot was telling us the cause. Unless we have alternative information he should be believed. 6. Why was the gear not retracted? Distraction, hydraulic failure, flap instead of gear, intentionally, the possibilities are endless. 7. If complete thrust loss occurred, other than a severe fuel issue, what could cause simultaneous flameout? That would be almost unimaginable, yet this is what the pilot allergy said happened. It would have massive ramifications if that gets confirmed. I don't think the video clips we have are clear enough to say anything at all at this stage. Flaps are hard to see on 787 imo for departure settings. All I can say is it appeared to climb well in the first seconds, then coinciding with the point that gear would usually be retracted, lift appears to very quickly be lost. That indicates sudden speed loss, or lift loss. Speed loss would be thrust, lift loss would be flap retraction if thrust was still available. The pilot allegedly reported thrust loss, that should be highest on the list of causes imo. In the case of double engine failure without any apparent outside influence visible on videos, that would be quite something for investigators to fathom. I don't know if anyone has data to show speed trend at the point the aircraft starts to descend, or a better audio for thrust variations at that point. I'm guessing that the update frequency on FR24 would be too slow to show that sudden change at the highest point achieved. We'll have the answers soon enough, all I can say is there appears to be no clear answers here without the data recorders or clear improved information. Indeed no conclusions whatsoever can be made as to crew actions either. RIP crew and passengers, condolences to the families. 1 user liked this post. |
tumtiddle
2025-06-13T08:16:00 permalink Post: 11900154 |
Are you kidding? The RAT is deployed (at least on Airbus) when you lose normal electrical supply. This will most likely never (or maybe once) happen in any pilots career.. So you most definitely have not heard "many hundreds" of 777/787 in that abnormal state.
As to the no flaps / flaps debate, time will tell. But what is definitely obvious is that they never raise the gear. Now that is tangible, and to me it seems that initially the aircraft is climbing at a somewhat steady climb until it doesn't. Having flown both Boeings and Airbus+ numerous other types over the years, on every type I have ever flown the initial action once positive climb is determined, is to raise the gear. This goes for every takeoff, normal or with failure of any sort (with the exception of a dual engine failure at rotation, which is not the case here, as they initially climbed to xxx hundred feet). So, initially the gear should have been retracted in order to minimise drag, and the question is, why was it not? Of course, once the gear is up, and in an instance where you get a dual engine failure at low level (highly rare) over land, then it is good arimanship to extend the gear in order for it to take some of the impact when a forced landing is inevitable. But why they did not raise the gear after rotation is a mystery to me. 23 users liked this post. |
MyTH
2025-06-13T08:47:00 permalink Post: 11900195 |
RAT? Here\x92s an unprocessed frame from the video. I really don\x92t see that the RAT has deployed.
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A4
2025-06-13T08:54:00 permalink Post: 11900208 |
Electrical AC loss results in the activation of an emergency geberator driven by the green system.
​​​​​​​A4 |
lakedude
2025-06-13T09:04:00 permalink Post: 11900214 |
Probably the best, early stage theory of the the cause that I have seen as yet. By a current 777 captain:
https://www.youtube.com/watch?v=z7EZkungFEE 4 users liked this post. |
Ngineer
2025-06-13T09:11:00 permalink Post: 11900223 |
I didn\x92t think this could be a dual engine failure related accident until reports of RAT deployment started to gather steam.
A few years back a B787 previously had a dual engine shutdown after rollout when the TR was deployed too quickly and not allowing the air/GND logic time to transition to ground mode before the TR deployed. If the TCMA had inadvertently latched the TR deployment from the previous rollout then it theoretically could be possible to shutdown on transition back to air mode. Anything is possible with these high tech machines. 2 users liked this post. |
flemingcool
2025-06-13T09:26:00 permalink Post: 11900239 |
I didn\x92t think this could be a dual engine failure related accident until reports of RAT deployment started to gather steam.
A few years back a B787 previously had a dual engine shutdown after rollout when the TR was deployed too quickly and not allowing the air/GND logic time to transition to ground mode before the TR deployed. If the TCMA had inadvertently latched the TR deployment from the previous rollout then it theoretically could be possible to shutdown on transition back to air mode. Anything is possible with these high tech machines. RIP to all the victims. |
Screamliner
2025-06-13T09:36:00 permalink Post: 11900252 |
Hi everyone, 787 driver here, well lets look at the facts we see
very late rotation, but pitch and departure path look like normal up until stalling point. mayday was called but without clarification or purpose, for me this indicates stress in the flight deck, especially low level no smoke or fire from engines, I would rule out severe damage or birdstrikes at this point Flaps 5 departure would be difficult to see as a pixel on a bad video, but they would not have made the rotation at that speed so I assume they used flaps during departure, also you would neglect to ECL's and a config warning no RAT to be seen either, again ruling out dual engine failure, also the climb would not have been so parabolic maybe single engine fuel starvation/Mechanical issue/dirty fuel, but seems unlikely, the flight path is too gentle Gear stays down, and even though the pitch remains the same, they start losing lift and basically stall the aircraft into the ground don't forget, Air India uses 64/67K engines on they're 787's, with temp of 41 degrees (ambient, so even more above tarmac) and a QNH of 1001, those engines will be pushed to "hard work mode" already IMHO, two things I could assume happend - either single engine failure, no pitch adjustment and speed fell below Vstall, OR, most likely - mixup of Flaps moved to up position in stead of Gear moved to up position, that would clarify the gear, would clarify the loss of lift and that the engines have no smoke, and no RAT, 10 users liked this post. |
DaveReidUK
2025-06-13T09:49:00 permalink Post: 11900263 |
4 users liked this post. |
bobbytables
2025-06-13T10:01:00 permalink Post: 11900273 |
Hi everyone, 787 driver here, well lets look at the facts we see
very late rotation, but pitch and departure path look like normal up until stalling point. mayday was called but without clarification or purpose, for me this indicates stress in the flight deck, especially low level no smoke or fire from engines, I would rule out severe damage or birdstrikes at this point Flaps 5 departure would be difficult to see as a pixel on a bad video, but they would not have made the rotation at that speed so I assume they used flaps during departure, also you would neglect to ECL's and a config warning no RAT to be seen either, again ruling out dual engine failure, also the climb would not have been so parabolic maybe single engine fuel starvation/Mechanical issue/dirty fuel, but seems unlikely, the flight path is too gentle Gear stays down, and even though the pitch remains the same, they start losing lift and basically stall the aircraft into the ground don't forget, Air India uses 64/67K engines on they're 787's, with temp of 41 degrees (ambient, so even more above tarmac) and a QNH of 1001, those engines will be pushed to "hard work mode" already IMHO, two things I could assume happend - either single engine failure, no pitch adjustment and speed fell below Vstall, OR, most likely - mixup of Flaps moved to up position in stead of Gear moved to up position, that would clarify the gear, would clarify the loss of lift and that the engines have no smoke, and no RAT, very late rotation - stated several times on this thread but zero evidence for it and some analysis suggests the rotation was at roughly the same location as previous departures of the same flight no RAT - others, including one with a lot of experience with the sound of a deployed RAT, insist that it was deployed. The video evidence is unclear. Not saying you\x92re necessarily wrong about anything but I take issue with those that state as fact things that are not (yet) supported by any evidence at all 18 users liked this post. |
tumtiddle
2025-06-13T10:10:00 permalink Post: 11900286 |
One has to assume that, given the seeming lack of lateral deviation from the flight path, and with no obvious yawing or rudder input visible on the videos, there's only two realistic conclusions here? Simultaneous dual engine failure of unknown cause if the RAT was indeed deployed; or flaps reduced too early leading to a stall if the RAT wasn't deployed.
Evidence in this thread would lean me toward the RAT deployed and therefore dual engine out scenario. As for the cause of that, well, only a couple of likely scenarios exist that could cause simultaneous shutdown of both engines, including mistaken or intentional use of the fuel cutoff levers. 3 users liked this post. |
Damonjames
2025-06-13T10:12:00 permalink Post: 11900291 |
I\x92d like to ask a legitimate question here regarding the runway footage.
there seems to be little to no change in aircraft attitude from point of lift off until just before impact. I have no experience on commercial jets, so I am waiting to be corrected, but first thing in engine failure after take off is lower the nose? If RAT deployed they should have at least been able to do so? The fact the attitude remains unchanged, would this not suggest they at least thought they had a chance of flying their way out of this situation? im sure 787 is not prone to pitot/static blockage? time will tell, until then we can only speculate I guess. |
MPN11
2025-06-13T10:28:00 permalink Post: 11900312 |
1 user liked this post. |
pampel
2025-06-13T10:46:00 permalink Post: 11900336 |
The idea that the flaps weren't set for take off also seems incredibly dubious given that in several frames of the original footage you can see the engines through the wings, on both sides, something not explainable by grainy footage or compression artifacts, and only possible if the flaps are down. Edit to add: the reports on social media from the previous passengers complaining about non-functional electronics have been confirmed Last edited by pampel; 13th Jun 2025 at 11:31 . 3 users liked this post. |
C2H5OH
2025-06-13T11:32:00 permalink Post: 11900388 |
One has to assume that, given the seeming lack of lateral deviation from the flight path, and with no obvious yawing or rudder input visible on the videos, there's only two realistic conclusions here? Simultaneous dual engine failure of unknown cause if the RAT was indeed deployed; or flaps reduced too early leading to a stall if the RAT wasn't deployed.
Evidence in this thread would lean me toward the RAT deployed and therefore dual engine out scenario. As for the cause of that, well, only a couple of likely scenarios exist that could cause simultaneous shutdown of both engines, including mistaken or intentional use of the fuel cutoff levers. |
Someone Somewhere
2025-06-13T11:34:00 permalink Post: 11900389 |
It's fine that the \x93Enhanced Airborne Flight Recorders\x94 have 10 minutes battery backup. If the bits of equipment/sensors sending data to be recorded don't have power, you will be recording 10 minutes of silence/blank data.
The concept of powering 'critical (sensor) equipment' has been floated - the problem being that it must be possible to power down malfunctioning equipment in case of fire - real or suspected. Having independent power supplies and battery back-ups all around the airframe, each with an ability to lose their magic smoke, is a poor idea. Commercial passenger jet aircraft already have robust power supplies with multiple generators and emergency battery support. However, if one malfunctions, rather than fails completely, it can be difficult to decide which one to disable, as it can cause problems in all systems. Once the RAT deployed at least some data should have come back.
Now, I am probably wrong about this, but if you forget to set the altitude window to the first altitude in departure and leave it at 0 (which with some airlines the previous crew will do on shutdown) the following might possibly occur. At 50 feet LNAV engages, at 100 feet the autopilot engages, at 400 feet VNAV engages but as the altitude window is set to 0 the aircraft (on autopilot) now descends to capture 0 feet. The speed at this point in VNAV is low (max V2 + 20 kts) so, to maintain that, both thrust levers close. This, of course, would be totally unexpected and could have a startle effect. If you do not realise what has caused this you might think that there is a problem with the engines and you have very little time to deal with it. I would suggest that putting out a Mayday call at this stage is not a good use of time.
As I stated at the beginning this is probably very unlikely and may not be possible, but could be tried in a simulator. It does not explain the RAT and generally you would expect crews to shove the thrust levers fully forward. 1 user liked this post. |
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