June 14, 2025, 12:22:00 GMT
permalink Post: 11901428
What evidence do we have that the RAT was deployed? All I can find is people talking about a "noise" which seems very thin evidence indeed.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): RAT (All) RAT (Deployment)
June 14, 2025, 16:56:00 GMT
permalink Post: 11901658
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): RAT (All)
June 15, 2025, 09:56:00 GMT
permalink Post: 11902306
(Sorry, Airbus here and not familiar with Boeing) Flap 5 to 1 reduction on the Boeing triggers autothrust reduction, is that correct? If so, are there any other conditions that need to be met for this to happen like being in some kind of takeoff mode? Just thinking whether this would have potential otherwise in other regimes to cause issues, discontinued approach perhaps.
Am slightly puzzled as to why if flap reduction triggering climb thrust is part of the standard logic (and presumably clean-up technique) then partial dual thrust loss wouldn’t be immediately recognised as the classic symptom of gear / flap retraction handling error? I presume Boeing pilots / air India are just as aware of this it as everyone else, strikes me as odd that one would immediately go into full dual EF mode. My instinctive reaction without knowing the Boeing would be to firewall both TLs, would this have worked in the early flap retraction logic scenario? Many thanks all
Am slightly puzzled as to why if flap reduction triggering climb thrust is part of the standard logic (and presumably clean-up technique) then partial dual thrust loss wouldn’t be immediately recognised as the classic symptom of gear / flap retraction handling error? I presume Boeing pilots / air India are just as aware of this it as everyone else, strikes me as odd that one would immediately go into full dual EF mode. My instinctive reaction without knowing the Boeing would be to firewall both TLs, would this have worked in the early flap retraction logic scenario? Many thanks all
Last edited by sorvad; 15th June 2025 at 10:15 .
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Engine Failure (All) Memory Items RAT (All)
June 15, 2025, 12:39:00 GMT
permalink Post: 11902431
So for those getting in the weeds with one in several trillion (or lower) probabilities of systems failures have you considered that that improper RTOW (with or without improper flap setting), flap retraction / climb thrust trigger, is of much higher probability and has actually happened ?
Anyway I think we’ll find out soon if a systems failure was involved.
The FLCH Hold thing (Asiana) was never an issue and well known (at least on our line). And for a crew of 3 (or 4) to press a destabilized approach getting 40-ish knots too slow (!) isn’t a systems problem — it’s a breach of basic airmanship.
Anyway I think we’ll find out soon if a systems failure was involved.
The FLCH Hold thing (Asiana) was never an issue and well known (at least on our line). And for a crew of 3 (or 4) to press a destabilized approach getting 40-ish knots too slow (!) isn’t a systems problem — it’s a breach of basic airmanship.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): APU
June 15, 2025, 17:19:00 GMT
permalink Post: 11902647
After hours of reading I conclude that so far nobody has the slightest clue about what happened.
1: Flaps were down
2: The RAT story is based on a single unsharp video frame. Earlier frames were much sharper but the RAT could not be seen (although there was a sound).
3. Lack of evidence
I could be wrong, in that case please link QUALITY evidence so that we can learn something new.
This way thousands of people are wasting countless hours.
1: Flaps were down
2: The RAT story is based on a single unsharp video frame. Earlier frames were much sharper but the RAT could not be seen (although there was a sound).
3. Lack of evidence
I could be wrong, in that case please link QUALITY evidence so that we can learn something new.
This way thousands of people are wasting countless hours.
Last edited by sorvad; 15th June 2025 at 17:35 .
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): APU RAT (All) RAT (Deployment)
June 15, 2025, 19:15:00 GMT
permalink Post: 11902740
We agree that there was a lack of thrust. Possibly caused by a dual engine failure. But the sharpest frames in the video do NOT show the RAT and this is counter evidence to the RAT theory. If there were substantial technical failures who knows what sounds could be generated. I find the evidence weak at best. And we immediately get into a chicken-egg problem: did some power issue of unknown nature cause an engine failure or did a dual engine failure occur, resulting in a power loss? Both are extremely unlikely and need to be backed by quality evidence. The video is not it, in my opinion. I don't know the APU intake mechanism and whether it could open after the impact.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): APU Dual Engine Failure Engine Failure (All) RAT (All) RAT (Deployment)
June 15, 2025, 19:34:00 GMT
permalink Post: 11902757
I've been sitting on my hands for days now...but please stop linking RAT deployment evidence with some blurry cluster of pixelation, which proves nothing.
This Pprune-forensic audio analysis (and subsequent posts) by Kraftstoffvondesibel, although completely ignored by many it seems, is the only clear proof there was a deployed RAT sound recorded in the young boy's video clip. You may disprove the analysis as much as you like, but referring to blurry video regarding possible RAT deployment or not, is indeed " thousands of people are wasting countless hours "
I'm rather under the impression that many recent discussions are going backwards or h amsterwheeling.
But thank you for your valuable audio analysis
This Pprune-forensic audio analysis (and subsequent posts) by Kraftstoffvondesibel, although completely ignored by many it seems, is the only clear proof there was a deployed RAT sound recorded in the young boy's video clip. You may disprove the analysis as much as you like, but referring to blurry video regarding possible RAT deployment or not, is indeed " thousands of people are wasting countless hours "
I'm rather under the impression that many recent discussions are going backwards or h amsterwheeling.
But thank you for your valuable audio analysis
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): RAT (All) RAT (Deployment)
June 17, 2025, 10:43:00 GMT
permalink Post: 11904189
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CVR
June 17, 2025, 11:11:00 GMT
permalink Post: 11904210
There is a possibility that doesn\x92t get much air time on this forum that satisfies all the \x91facts\x92 ( pprune facts mind you), and requires less mental gymnastics to believe than many of the theories put forward. I\x92m not saying it\x92s what happened at all but it seems much more likely than a TCMA fault to me.
This link is to a Japanese report on a Jetstar 787-8 with GE engines that had both engines drop below idle while airborne due to magnesium salts effecting the operation of the FSV spools. The Magnesium salts came from a biocide dose by maintenance two days earlier.
For some reason I can\x92t paste the link but if you google JTSB the report number is AI2020-2.
I think it\x92s quite easy to imagine that a simple maintenance error ( 1000ppm instead of 100ppm) combined with extremely bad luck on timing lead to this accident.
I think I\x92m favouring a theory like this for its simplicity and the fact that fuel is the elephant in the room when you are dealing with a dual engine failure.
This link is to a Japanese report on a Jetstar 787-8 with GE engines that had both engines drop below idle while airborne due to magnesium salts effecting the operation of the FSV spools. The Magnesium salts came from a biocide dose by maintenance two days earlier.
For some reason I can\x92t paste the link but if you google JTSB the report number is AI2020-2.
I think it\x92s quite easy to imagine that a simple maintenance error ( 1000ppm instead of 100ppm) combined with extremely bad luck on timing lead to this accident.
I think I\x92m favouring a theory like this for its simplicity and the fact that fuel is the elephant in the room when you are dealing with a dual engine failure.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Engine Failure (All) Maintenance Error
June 17, 2025, 19:59:00 GMT
permalink Post: 11904605
Couple of recent bits of news….
https://www.reuters.com/sustainabili...ne-2025-06-17/
https://www.reuters.com/world/india/...et-2025-06-17/
https://www.reuters.com/sustainabili...ne-2025-06-17/
https://www.reuters.com/world/india/...et-2025-06-17/
Subjects: None
June 18, 2025, 17:17:00 GMT
permalink Post: 11905409
Water was mentioned earlier in the previous iteration of this thread, as I recall by one of the most well respected contributors on the forum and an expert in flight testing and certification issues. There have been a couple of well known incidents of flight deck screens going blank due to all sorts of electrical problems caused by water ingress into the E&E bay, fortunately in daytime vmc and not on particularly electric jets, and both I believe at rotation. The one I recall had it’s L1 door left open during a black rainstorm in Hong Kong. It’s also been said that total electrical failure can’t result in in a double engine failure on the 787, but I wonder what multiple sequelae could result from such water contamination with an aeroplane that relies so much on electrical power and software? Another very remote probability but many accidents and incidents are. I don’t even know if there was any inclement weather before this flight, maybe someone could confirm?
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Electrical Failure Engine Failure (All)
June 18, 2025, 17:35:00 GMT
permalink Post: 11905416
Water was mentioned earlier in the previous iteration of this thread, as I recall by one of the most well respected contributors on the forum and an expert in flight testing and certification issues. There have been a couple of well known incidents of flight deck screens going blank due to all sorts of electrical problems caused by water ingress into the E&E bay, fortunately in daytime vmc and not on particularly electric jets, and both I believe at rotation. The one I recall had it’s L1 door left open during a black rainstorm in Hong Kong. It’s also been said that total electrical failure can’t result in in a double engine failure on the 787, but I wonder what multiple sequelae could result from such water contamination with an aeroplane that relies so much on electrical power and software? Another very remote probability but many accidents and incidents are. I don’t even know if there was any inclement weather before this flight, maybe someone could confirm?
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Electrical Failure Engine Failure (All)
June 19, 2025, 06:29:00 GMT
permalink Post: 11905757
Non-aviation engineer here: I have a question about the low level altitude capture theory that I've been a bit hesitant to ask, since no-one else seemed to be bringing it up.
My understanding of altitude capture is that the autopilot will automatically adjust both thrust and pitch to intercept the requested altitude. However to my eyes there is very little pitch adjustment in the CCTV video of the plane taken from behind, until the very end of the video when it pitches up somewhat (obscured by buildings, more visible in the smartphone video). Please correct me if I'm wrong but I'd have thought that if the autopilot was trying to capture a very low altitude it would start pitching down (quite noticeably!) to do so, not remain at what looks like 10+ degrees nose-up. I honestly struggle to reconcile what I'm looking at in the video with an attempt to level off at 0ft, 200ft, or any of the other mentioned low-level altitudes.
Also maybe I'm missing something 787-specific but generally doesn't the autopilot have to be activated for the aircraft to automatically attempt to capture the pre-selected altitude? That was the case in this incident involving a Dash 8 and a target altitude of 0 feet that I am reading about ( https://www.gov.uk/aaib-reports/aaib...-dash-8-g-ecoe ). I'd have thought the PF would still be hand-flying the departure at the point that things went wrong, considering that the gear hadn't even been retracted yet...
My understanding of altitude capture is that the autopilot will automatically adjust both thrust and pitch to intercept the requested altitude. However to my eyes there is very little pitch adjustment in the CCTV video of the plane taken from behind, until the very end of the video when it pitches up somewhat (obscured by buildings, more visible in the smartphone video). Please correct me if I'm wrong but I'd have thought that if the autopilot was trying to capture a very low altitude it would start pitching down (quite noticeably!) to do so, not remain at what looks like 10+ degrees nose-up. I honestly struggle to reconcile what I'm looking at in the video with an attempt to level off at 0ft, 200ft, or any of the other mentioned low-level altitudes.
Also maybe I'm missing something 787-specific but generally doesn't the autopilot have to be activated for the aircraft to automatically attempt to capture the pre-selected altitude? That was the case in this incident involving a Dash 8 and a target altitude of 0 feet that I am reading about ( https://www.gov.uk/aaib-reports/aaib...-dash-8-g-ecoe ). I'd have thought the PF would still be hand-flying the departure at the point that things went wrong, considering that the gear hadn't even been retracted yet...
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CCTV
July 10, 2025, 16:03:00 GMT
permalink Post: 11919111
Aaaaand here we go again 🤦♂️
Subjects: None
July 11, 2025, 21:56:00 GMT
permalink Post: 11919865
It would be nice to see a graph of g forces/turbulence. An awkward arm or hand position in combination with sudden turbulence and perhaps worn out switches could hit both of them.
Sleeves or lanyards that got caught while moving around? Perhaps there was an attempt to press a radio button, although it would be a strange time to do that. But perhaps an 'oh crap, I forgot to get that frequency ready' moment.
Sleeves or lanyards that got caught while moving around? Perhaps there was an attempt to press a radio button, although it would be a strange time to do that. But perhaps an 'oh crap, I forgot to get that frequency ready' moment.
Subjects: None
July 12, 2025, 07:42:00 GMT
permalink Post: 11920296
Timeline of known events with source attribution from the preliminary report:
08:07:33 ATC: Takeoff clearance
08:07:37 A-SMGCS: Aircraft starts rolling
08:08:33 EAFR: V1 153kts
08:08:35 EAFR: Vr 155kts
08:08:39 EAFR: Gnd-Air mode transition
08:08:42 EAFR: Max IAS 180kts, Eng 1/2 Cutoff switches activate within 1 second of each other
08:08:42 CVR: "Why did you cut off", "I did not" (exact time not specified)
08:08:42 A-SMGCS: RAT deployed (exact time not specified)
08:08:47 EAFR: Both engine N2 below min idle. RAT hyd pwr commences
08:08:52 EAFR: Eng 1 cutoff to RUN
08:08:54 EAFR: APU inlet door opens (auto start logic)
08:08:56 EAFR: Eng 2 cutoff to RUN
08:09:05 ATC: Mayday call
08:09:11 EAFR recording stops
Fuel cutoff switches operated within 1 second of each other suggests to me that the locking mechanism wasn't working as per (SAIB) No. NM-18-33. Any loose item could have accidentally (or not) operated the switches (including hands).
08:07:33 ATC: Takeoff clearance
08:07:37 A-SMGCS: Aircraft starts rolling
08:08:33 EAFR: V1 153kts
08:08:35 EAFR: Vr 155kts
08:08:39 EAFR: Gnd-Air mode transition
08:08:42 EAFR: Max IAS 180kts, Eng 1/2 Cutoff switches activate within 1 second of each other
08:08:42 CVR: "Why did you cut off", "I did not" (exact time not specified)
08:08:42 A-SMGCS: RAT deployed (exact time not specified)
08:08:47 EAFR: Both engine N2 below min idle. RAT hyd pwr commences
08:08:52 EAFR: Eng 1 cutoff to RUN
08:08:54 EAFR: APU inlet door opens (auto start logic)
08:08:56 EAFR: Eng 2 cutoff to RUN
08:09:05 ATC: Mayday call
08:09:11 EAFR recording stops
Fuel cutoff switches operated within 1 second of each other suggests to me that the locking mechanism wasn't working as per (SAIB) No. NM-18-33. Any loose item could have accidentally (or not) operated the switches (including hands).
Last edited by sorvad; 12th July 2025 at 08:03 . Reason: Clarification
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): APU CVR EAFR Fuel (All) Fuel Cutoff Fuel Cutoff Switches MAYDAY Pilot "Why did you cut off" Preliminary Report RAT (All) RAT (Deployment) RUN/CUTOFF SAIB NM-18-33 Special Airworthiness Information Bulletin Timeline (Preliminary Report) V1
July 12, 2025, 08:26:00 GMT
permalink Post: 11920339
Probably not during Takeoff I wouldn\x92t have thought.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Fuel Cutoff Switches Fuel Cutoff Switches (detent)
July 12, 2025, 22:28:00 GMT
permalink Post: 11920888
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Switches
July 14, 2025, 08:44:00 GMT
permalink Post: 11921964
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Fuel Cutoff Switches
July 14, 2025, 16:17:00 GMT
permalink Post: 11922332
Former Boeing Engineer who was in the room for some 787 AD discussions.... What exactly would you expect Boeing to put in the AD? "Don't put the fuel switches to cutoff unless you really mean to"? Let alone ADs are not in anyway a method for pilot training or actions, they are for the airline engineering and maintenance teams. What would you think Boeing should ask airlines to do in this proposed AD?
I'm sure the current team has already done the systems analysis to see if there was any possible way these weren't completely isolated systems (which I'm pretty confident they are). Let alone the initial report categorically says at this point there are no design issues found with Boeing or GE.
I'm sure the current team has already done the systems analysis to see if there was any possible way these weren't completely isolated systems (which I'm pretty confident they are). Let alone the initial report categorically says at this point there are no design issues found with Boeing or GE.
Last edited by sorvad; 14th July 2025 at 21:11 .
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Air Worthiness Directives Fuel (All) Fuel Cutoff Switches Preliminary Report