Civil Aviation Development & Discussion

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chetak
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Re: Civil Aviation Development & Discussion

Post by chetak »

Tanaji wrote: 13 Jul 2025 13:50
Vayutuvan wrote: 13 Jul 2025 06:13

Exactly my doubt as well. Switch positions can be seen only if there are pictures. Am I correct in saying that CVR and FDR do not have any imaging capability? My understanding is that they record voice and sensor data. I can understand why video is not there. But why not record images of the cockpit during take off and landing? Those are almost always the critical periods for the aircraft.
There was no video recording - the option is available for 787 but was not exercised. NTSB had suggested video feeds be sent to CVR but could not mandate it due to objections from the pilot lobby.

The report is remarkable for being thorough and not commenting on other aspects. I suspect that by the time they did not have enough information to say conclusively one or the other.

We don’t know if the switch is a physical switch or just one masquerading for a software one. I suspect it’s the latter.



Tanaji saar,

The switches are physical (switch is a two-position 'latching' switch with a physical detent to prevent inadvertent operation-- see red arrow in picture showing the detent) and the physically selected position of either "run" or "cutoff" is electrically sensed and recorded with time stamp by the flight data recorder

Ultimately, it is an electrical signal that is sent by this fuel cutoff switch(es) (when selected to the cutoff position) to the spar fuel valve(s) that cuts off fuel supply to the selected engine(s), and causing either one or both engines to shut down immediately

Image
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Re: Civil Aviation Development & Discussion

Post by tandav »

vera_k wrote: 13 Jul 2025 10:26 Expert Claims Pilot May Have Deliberately Crashed Air India Flight
many Indian airlines and even the Directorate General of Civil Aviation (DGCA) have failed to adopt mental health safeguards for pilots, despite repeated warnings.
Probably on the pay of Boeing. This expert has given similar testimony in other cases
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Re: Civil Aviation Development & Discussion

Post by chetak »

vi@shiv aroor

This 2018 FAA bulletin (SAIB NM-18-33) warns of a flaw in fuel control switches on Boeing models like 737 MAX, 787, etc. The locking mechanism can disengage, risking accidental engine shutdown mid-flight if a pilot bumps it. It's advisory, not mandatory—recommends inspections and replacements. Tied to recent Air India 787 crash probe, but no proven link yet. Boeing's fix: upgraded switches.



Image

Image
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Re: Civil Aviation Development & Discussion

Post by Ambar »

The above is a advisory and not mandatory because you may accidentally "bump" into one of the switches but not both which have independent controls. A pilot has made a video of him cutting off the engines by operating one switch after another and you can watch for yourself and see how likely it is for an experienced pilot to accidentally cut off both engines at the same time.

https://www.instagram.com/reel/DMBK6JoS ... U2c3FnaHo0

As for the theory that engine had a malfunction which necessitated recycling it, there are 3 things to remember -

1. Nothing in the FVR contents releases so far suggests there was a problem with the engine.
2. If there was then both pilots would agree to recycle the engine and not one making a unilateral decision just after hitting VLOF.
3. Boeing and Airbus both have strict guidance against restarting the engines during TOGA below 400ft.

Not sure the hate for Capt Mohan Ranganathan, he flew Boeings throughout his career and was also a trainer, i'd take his words over someone like Capt Augustine who have no experience flying these planes.

The unfortunate thing is it maybe years before we get the full report, and the usual conspiracies will continue until then if we haven't moved on already to a different tragedy.
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Re: Civil Aviation Development & Discussion

Post by chetak »

Ambar wrote: 13 Jul 2025 19:30 The above is a advisory and not mandatory because you may accidentally "bump" into one of the switches but not both which have independent controls. A pilot has made a video of him cutting off the engines by operating one switch after another and you can watch for yourself and see how likely it is for an experienced pilot to accidentally cut off both engines at the same time.

https://www.instagram.com/reel/DMBK6JoS ... U2c3FnaHo0

As for the theory that engine had a malfunction which necessitated recycling it, there are 3 things to remember -

1. Nothing in the FVR contents releases so far suggests there was a problem with the engine.
2. If there was then both pilots would agree to recycle the engine and not one making a unilateral decision just after hitting VLOF.
3. Boeing and Airbus both have strict guidance against restarting the engines during TOGA below 400ft.

Not sure the hate for Capt Mohan Ranganathan, he flew Boeings throughout his career and was also a trainer, i'd take his words over someone like Capt Augustine who have no experience flying these planes.

The unfortunate thing is it maybe years before we get the full report, and the usual conspiracies will continue until then if we haven't moved on already to a different tragedy.



Ambar ji,

you are quoting instagram and drawing conclusions from a barebones preliminary report. The CVR itself has just one sentence that has been made public. Nothing about what was said either before or after the engines lost thrust

ye to sirf trailer hai, picture abhi baaki hai

that's probably what that clown m0h@n r did, go on teevee and blame people who cannot defend themselves. That's mean, arrogant and motivated, and downright stupid. No other "aviation expert" has done so in India, so what's so very special about this conceited dirtbag that he has to mouth off in public.


This report could take about a year to compile and release

It cannot be stalled, doctored, or delayed without serious consequences for a number of aviation entities world wide

too many airlines spread globally, aviation professionals worldwide, and many countries (all flying the 787) are anxiously awaiting this report. If not released on time, it could have disastrous consequences for Indian aviation regulatory authorities and the civil aviation aviation industry. As of now, one hears that the sarkari babooze will all be replaced by seasoned aviation professionals in the short to medium term

opinions are like @h0le$, everyone has one, especially those intent on airing their gavar opinions on teevee



Preliminary crash report contains this image — grab of AI171 from a third CCTV that captured the takeoff.

Image

Meaning that at this point of the takeoff, the engine rpms had already rolled back and slowed to some sub optimal levels that took the engine driven generators off line, and triggering the software to deploy the RAT. The APU was also in the process of starting up

It is not clear as to which flight control laws or flight mode that they were in, but possibly, their full functionality would have been degraded, allowing limited flight control options available to the flight crew
Aircraft with fly-by-wire flight controls require computer controlled flight control modes that are capable of determining the operational mode (computational law) of the aircraft. A reduction of electronic flight control can be caused by the failure of a computational device, such as a flight control computer, an information providing device, such as the Air Data Inertial Reference Unit (ADIRU) or the failure of multiple systems (dual hydraulic failure, dual engine failure etc). Electronic flight control systems (EFCS) also provide augmentation in normal flight, such as increased protection of the aircraft from overstress or providing a more comfortable flight for passengers, by recognizing and correcting for turbulence and providing yaw damping.

Two aircraft manufacturers produce commercial passenger aircraft with primary flight computers that can perform under different flight control modes (or laws). The most well-known are the Normal, Alternate and Direct Laws.

Boeing flight control laws can degrade due to various factors, leading to reduced functionality or even complete loss of some flight control protections. These degradations can be caused by system failures, sensor malfunctions, or when the aircraft transitions between different flight phases or control modes. Understanding these degradation modes is crucial for pilots to maintain safe aircraft control.

A reduction of electronic flight control can be caused by the failure of a computational device, such as a flight control computer, an information providing device, such as the Air Data Inertial Reference Unit (ADIRU) or the failure of multiple systems (dual hydraulic failure, dual engine failure etc). Electronic flight control systems (EFCS) also provide augmentation in normal flight, such as increased protection of the aircraft from overstress or providing a more comfortable flight for passengers, by recognizing and correcting for turbulence and providing yaw

The 787 is a fly by wire platform
There were no unilateral decisions in the cockpit. Both pilots were trying to salvage the situation. The pilot flying (PF) was Kundra, the Copilot, and the pilot monitoring (PM) was the Captain.

One is pretty sure that the captain, who was also instructor qualified, would have taken over the controls within a few seconds of the emergency manifesting. Dual engine failure on take off is a single point failure mode and there are very few instances of recovery, unless the aircraft has gained sufficient height, allowing the flight crew to circle back and land back on the runway or find some clear ground to let down. This crew did not have either of those options.



Boeing and Airbus both have strict guidance against restarting the engines during TOGA below 400ft.

BTW, In an actual emergency, no one ever follows this rule. They all get on the controls ASAP, and handle the emergency as best they can, but in a simulator they always do or else they get failed and rescrubbed leaving a black mark on their records, and probably get invited to the chief pilot's office for some tea and biscuits which will precede the unpleasantries that will surely follow
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Re: Civil Aviation Development & Discussion

Post by Ambar »

You're making a series of assumptions to support your narrative and appear to have a particular grievance against Capt. Mohan Ranganathan who, incidentally, is far more qualified than many self-styled "keyboard pilots." This isn’t just some "random Instagram video"; it's a demonstration by a Boeing pilot showing the exact operation of the engine cutoff switches identical to those used on the 787, including how long it takes to shut down both engines.

Manufacturer guidelines exist for a reason. Neither the AAIB nor the Min of Civil Aviation has indicated that the pilots were attempting to recover from an emergency by restarting the engines immediately after VLOF. In fact, the released portion of the CVR suggests the opposite: one pilot questions why the engines were shut off, and the other denies having done so.

The irony here is striking the same people who applauded the PMO’s decision to withhold the black boxes from the NTSB and have the AAIB investigate at home are now questioning the government’s motives. But then again, conspiracy theories sell, while straightforward facts are boring.
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Re: Civil Aviation Development & Discussion

Post by chetak »

Ambar wrote: 13 Jul 2025 22:12 You're making a series of assumptions to support your narrative and appear to have a particular grievance against Capt. Mohan Ranganathan who, incidentally, is far more qualified than many self-styled "keyboard pilots." This isn’t just some "random Instagram video"; it's a demonstration by a Boeing pilot showing the exact operation of the engine cutoff switches identical to those used on the 787, including how long it takes to shut down both engines.

Manufacturer guidelines exist for a reason. Neither the AAIB nor the Min of Civil Aviation has indicated that the pilots were attempting to recover from an emergency by restarting the engines immediately after VLOF. In fact, the released portion of the CVR suggests the opposite: one pilot questions why the engines were shut off, and the other denies having done so.

The irony here is striking the same people who applauded the PMO’s decision to withhold the black boxes from the NTSB and have the AAIB investigate at home are now questioning the government’s motives. But then again, conspiracy theories sell, while straightforward facts are boring.
just drop this matter.
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Re: Civil Aviation Development & Discussion

Post by Vayutuvan »

chetak wrote: 13 Jul 2025 15:20 The switches are physical (switch is a two-position 'latching' switch with a physical detent to prevent inadvertent operation-- see red arrow in picture showing the detent) and the physically selected position of either "run" or "cutoff" is electrically sensed and recorded with time stamp by the flight data recorder

Ultimately, it is an electrical signal that is sent by this fuel cutoff switch(es) (when selected to the cutoff position) to the spar fuel valve(s) that cuts off fuel supply to the selected engine(s), and causing either one or both engines to shut down immediately
...
I am sure there are several analog circuit designer here.

I forgot most of my electrical engg but isn't it possible to rig a simple RLC circuit (we don't even need a 555 but it would make it much easier) to send the electrical signal? It has to have a self-destruct feature (a zener diode with a enough low resistance which will not limit the current flowing through the zener diode in the reverse direction). One can even think of a small amount of explosive that explodes the circuit away. After the crash, it would be very difficult to recover the circuit, especially if a small amount of explosive is used.
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Re: Civil Aviation Development & Discussion

Post by A_Gupta »

The CVR itself has just one sentence that has been made public. Nothing about what was said either before or after the engines lost thrust.
I repeat, some information has been provided to draw the reader to a conclusion, but there are simply not enough relevant facts provided to support this seemingly natural conclusion. Nor does the report itself draw this conclusion. The final report with full details could go any direction as to the cause of the accident without contradicting the preliminary report.

For example:
"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."

No timestamp is given for this. It is immediately followed by something else with no timestamp.

"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 CCTV footage obtained from the airport showed Ram Air Turbine (RAT) getting deployed during the initial climb immediately after lift-off (fig. 15). No significant bird activity is observed in the vicinity of the flight path. The aircraft started to lose altitude before crossing the airport perimeter wall."

Time stamps are given for everything else:

Timestamps:

1. As per the EAFR data, the aircraft crossed the take-off decision speed V1 and achieved 153 kts IAS at 08:08:33 UTC.

2. The Vr speed (155 kts) was achieved as per the EAFR at 08:08:35 UTC. T

3. he aircraft air/ground sensors transitioned to air mode, consistent with liftoff at 08:08:39 UTC.

4.. The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off.

Break from timestamps: "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 CCTV footage obtained from the airport showed Ram Air Turbine (RAT) getting deployed during the initial climb immediately after lift-off (fig. 15). No significant bird activity is observed in the vicinity of the flight path. The aircraft started to lose altitude before crossing the airport perimeter wall."

Resume timestamps:

5.. As per the EAFR data both engines N2 values passed below minimum idle speed, and the RAT hydraulic pump began supplying hydraulic power at about 08:08:47 UTC.

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

7. The APU Inlet Door began opening at about 08:08:54 UTC, consistent with the APU Auto Start logic.

8. Thereafter at 08:08:56 UTC the Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN.

9.. At about 08:09:05 UTC, one of the pilots transmitted “MAYDAY MAYDAY MAYDAY”.

Why is the timestamp missing from what one pilot is saying to the other, and the reply? It is a deliberate ambiguity, in my opinion; and the sentence about no bird strikes also doesn't belong there either. We know about the RAT from the EAFR (5.), with a precise timestamp.
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Re: Civil Aviation Development & Discussion

Post by Vayutuvan »

Ambar wrote: 13 Jul 2025 19:30 The above is a advisory and not mandatory because you may accidentally "bump" into one of the switches but not both which have independent controls.
I am questioning why Boeing didn't make into an AD, i.e. directive which is mandatory. The problem seems top be serious enough to warrant a mandatory directive.
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Re: Civil Aviation Development & Discussion

Post by vera_k »

Amid Air India probe, US FAA, Boeing notify fuel switch locks are safe, document, sources say
The FAA's notification to Civil Aviation Authorities, seen by Reuters, said: "although the fuel control switch design, including the locking feature, is similar on various Boeing airplane models, the FAA does not consider this issue to be an unsafe condition that would warrant an Airworthiness Directive on any Boeing airplane models, including the Model 787."
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Re: Civil Aviation Development & Discussion

Post by Vayutuvan »

A_Gupta wrote: 14 Jul 2025 00:51 ...
4.. The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off.

Break from timestamps: "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 CCTV footage obtained from the airport showed Ram Air Turbine (RAT) getting deployed during the initial climb immediately after lift-off (fig. 15). No significant bird activity is observed in the vicinity of the flight path. The aircraft started to lose altitude before crossing the airport perimeter wall."

Resume timestamps:

5.. As per the EAFR data both engines N2 values passed below minimum idle speed, and the RAT hydraulic pump began supplying hydraulic power at about 08:08:47 UTC.
...
Isn't it safe to assume then that short conversation took place between 08:08:42 UTC and 08:08:47 UTC?
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Re: Civil Aviation Development & Discussion

Post by vera_k »

The only thing that makes sense to me as to why the CVR transcript is not released is that an active investigation is under way. And they do not want to tip off any actors involved.
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Re: Civil Aviation Development & Discussion

Post by Vayutuvan »

vera_k wrote: 14 Jul 2025 01:21
The FAA's notification to Civil Aviation Authorities, seen by Reuters, said: "although the fuel control switch design, including the locking feature, is similar on various Boeing airplane models, the FAA does not consider this issue to be an unsafe condition that would warrant an Airworthiness Directive on any Boeing airplane models, including the Model 787."
It is quite possible that someone at FAA called this incorrectly. I am still at a loss as to why and how the locking mechanism can be disabled. Whether a pilot can cutoff both within a second accidentally is besides the point. I am inclined to believe that this is a red herring and make way to the accusing one or both the pilots of incompetence at best.

But both have 19K hours of flying time. They had adequate rest and also passed the breathalyzer test (just before they got into the cockpit, I presume, unless ofc one of the crew members handed them a couple of stiff scotches).
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Re: Civil Aviation Development & Discussion

Post by Vayutuvan »

vera_k wrote: 14 Jul 2025 01:30 The only thing that makes sense to me as to why the CVR transcript is not released is that an active investigation is under way. And they do not want to tip off any actors involved.
That makes eminent sense.
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Re: Civil Aviation Development & Discussion

Post by A_Gupta »

Vayutuvan wrote: 14 Jul 2025 01:25 Isn't it safe to assume then that short conversation took place between 08:08:42 UTC and 08:08:47 UTC?
You should not be forced to make that assumption. ( It might turn out to be a safe assumption, of course.)

IMO, and it is just me, I would have broken out the EAFR evidence as one section, the cockpit voice recorder as a second section, the CCTV as a third section and so on.

Since the fuel switches are crucial, not just telling us that the fuel switches were found in the RUN position in the wreckage, but also that the locking mechanism against accidental switch flips was (or was not) still working. (Section 6, Wreckage and Impact: "Both fuel control switch were found in the “RUN” position. (fig.13)")"

In the cockpit voice recorder section, either they say, the analysis is ongoing, or they give a more complete narration - e.g., from pre-flight checks to takeoff, the pilot and co-pilot said the standard things that are said during this phase and all seems normal. At timestamp XYZ, N seconds (plus or minus as it is) the captain (or whomever) is heard asking the co-pilot why he flipped the fuel control switch, etc. In the subsequent few seconds we hear the captain saying he is taking over, mouthing the standard emergency checklist (or not, as the case may be). At timestamp ABC, the Mayday, Mayday, Mayday is heard.

Then a section to say what has been ruled out:

1. CCTV (and maybe EAFR) rules out bird strike.
2. Lines of evidence A,B,C rule out any obvious equipment malfunction (or don't rule it out, so still under analysis)
3 Other causes - still under investigation, or name them as ruled out.

In this kind of report, no one should have to draw inferences. Assumptions are dangerous.
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Re: Civil Aviation Development & Discussion

Post by srin »

Only two questions:
- Is it possible to turn off both fuel control switches within 1 second of each other ?
- Is it possible that the switches turn off automatically (without manual intervention) under some circumstance?
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Re: Civil Aviation Development & Discussion

Post by sanjaykumar »

When the Air France went down in the south Atlantic because of pilot inability to fly the machine, I had posted the possibility of real time remote piloting of stricken aircraft. Apparently this is doable/being done. According to X.

Boeing also had non mandatory inspection advisories regarding these very switches from 737 experience.

The truth may never be known. There are tens of billions in share holder vale, corporate and national prestige at stake.

India will not cancel the hundreds of Boeings on order.
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Re: Civil Aviation Development & Discussion

Post by vera_k »

Prior incident a long time back where both both engines were shut off by mistake due to other things happening with the plane.

INADVERTENT ENGINE SHUTOFF PROMPTS F.A.A. ORDER ON BOEING 767'S
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Re: Civil Aviation Development & Discussion

Post by A_Gupta »

From Bing Co-Pilot (i.e., AI)
Sample Transcript of a Normal Boeing 787-9 Takeoff (Pilot & First Officer)
Below is a representative cockpit‐voice transcript from a routine Boeing 787-9 departure. Actual airline CVR recordings for non-incident flights are not publicly released, so this sample is constructed from standard Boeing call-out procedures.

Code: Select all

Time (Local)	Speaker	Callout / Dialogue
07:15:00	FO	Pushback clear. Commencing engine start.
07:15:05	Capt	Engine 1 start valve—open.
07:15:20	FO	Engine 1 stabilized at idle.
07:15:25	Capt	Engine 2 start valve—open.
07:15:40	FO	Engine 2 stabilized at idle.
(APU off, IRS alignment complete)
07:17:10	FO	“Flaps 5, trim green.”
07:17:12	Capt	“Flaps 5, trim green.”
07:18:00	ATC	“Expect runway 09R departure, heading 090, cleared for taxi.”
07:18:15	FO	“Taxi checklist complete. Line up runway 09R, call when ready.”
07:19:30	Capt	“Ready on 09R.”
07:19:32	ATC	“Cleared for takeoff 09R, heading 090.”
07:19:40	FO	“Thrust levers—takeoff detent.”
07:19:45	Capt	“Thrust set. Engine instruments—green.”
07:19:50	FO	“80 knots.”
07:19:55	FO	“100 knots.”
07:20:00	FO	“V1.”
07:20:01	FO	“Rotate.”
07:20:04	Capt	“Positive rate.”
07:20:07	FO	“Gear up.”
07:20:15	Capt	“Flaps up.”
07:20:30	FO	“Autopilot on. Heading select.”
07:21:00	Capt	“Climb thrust. Passing 2 000 feet.”
Pilots say “Rotate” when the airplane reaches its predetermined rotation speed (Vr), the minimum speed at which the nose can be lifted safely to generate enough lift for takeoff.

“Positive rate” is the callout confirming that the aircraft’s vertical speed indicator shows any climb rate above zero, meaning the airplane is safely ascending off the runway. Once this is observed, the pilot monitoring announces “Positive rate, gear up,” and the flying pilot retracts the landing gear to reduce drag and continue the climb.

The prelim report says: "The Vr speed (155 kts) was achieved as per the EAFR at 08:08:35 UTC." So we expect pilot/co-pilot to have said "Rotate" or its equivalent at that time.

In this: "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." --- insert this into the normal sequence.
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Re: Civil Aviation Development & Discussion

Post by A_Gupta »

This commercial pilot (American I think) raises much the same questions everyone else is.

https://www.youtube.com/live/VI4fY-CJ1D ... Vho-FGIn_s

And upfront:
And the more I've read through this preliminary report, it shows me that, you know, people are already jumping to conclusions. And I just want to say right off the bat, let's not forget when the 737 Max crashed, we had an issue where everybody basically in the media and just the general consensus was putting the blame on the pilots instead of oh wait, it turned out to be a software glitch glitch from Boeing. So I am just want to say that we still need to be very careful. We can talk now about theories because at this point I think it's okay to speculate and at least talk about the the what options we have because we're basically down to three. But keep that in mind. We had the Boeing 737 Max where everybody basically said, "Oh, these pilots I remember the the the logic at the time." And I remember pilots talking and just saying, "Man, look at that training in those other countries." And turns out that was very premature.
So, going back to this preliminary report, I wanted to point out that a lot of what you guys said. So, this is insinuation but not proof because remember they I don't want to say conveniently, but they left out some critical timestamps in this this report.
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Re: Civil Aviation Development & Discussion

Post by A_Gupta »

FYI, apparently some planes do not let you cut off the fuel to the engines unless the throttle is in the idle state.
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Re: Civil Aviation Development & Discussion

Post by vera_k »

From the passengers' point of view, the preliminary report is being seen as a coverup protecting both the airline and the manufacturer.

Probe report a cover up
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Re: Civil Aviation Development & Discussion

Post by Amber G. »

Image
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Re: Civil Aviation Development & Discussion

Post by Cyrano »

This is the Google translation of a post on Quora by a certain Jean Philippe Brunet, ex Directeur of Innovation, Thales Air Systems. He doesn't cite a source for this, was posted on 7 July . Take it FWIW
Crash of Air India Flight 171 on June 12, 2025 Of course, we'll have to wait for the final report, but the facts revealed by the black boxes are damning. We now know the cause of the Air India crash, which saw a Boeing Dreamliner on takeoff crash into a medical school building after losing thrust in both engines. The black boxes have spoken, and it's not to Boeing's credit. The captain's seat suddenly moved backward at the most critical moment when maximum thrust was applied on takeoff. Surprised, he grabbed the throttle levers and violently forced both levers fully backward, causing both engines to idle and then shut down. Surprised, he reacted by concentrating for a few seconds on his seat problem while the co-pilot noticed the total loss of thrust and took a few seconds to realize the situation without immediately understanding what was happening with the thrust levers. During these few lost seconds, both engines stopped. From then on, the plane was doomed and the fatal outcome became inevitable. It crashed into the medical school building at more than 300 km per hour.
This type of incident had already occurred on a Dreamliner, but the pilots managed to recover from the situation because it was at a less critical moment in the flight. The plane that crashed had experienced problems with the captain's seat, which had been repaired the day before. The pin that prevents the seat from moving backward had been replaced, but preliminary investigation findings show that the seat had not been tested following this part change. It is unclear at this time whether this was an error in Boeing's confidential maintenance manual or negligence on the part of the Indian technicians responsible for the repair. At the time the Dreamliner was being designed, Boeing was still in its cost-cutting phase to increase profits and maintain its market share. This dramatic period is now, in principle, over following the two 737 MAX crashes and the serious quality problems that arose in its production, which forced the company to rectify its situation following the complete loss of confidence of certification authorities and airlines.


At the time, Boeing was heading for a crash, and unfortunately, a Boeing Dreamliner literally did. As usual in this type of accident, it took several slices of cheese with a hole in the same place for the deficiencies to ultimately cascade and cause a catastrophe. The investigations show how saving on a pin costing a few euros for a pilot's seat costing tens of thousands of euros could have caused the loss of an aircraft worth several hundred million euros and the deaths of several hundred people. The investigation will show whether the technicians who changed the pin and did not test the seat were negligent or whether Boeing's maintenance manual was at fault. What is certain is that this defect was known to Boeing, that it had already nearly caused a catastrophe, and at the current stage of the investigation, there had been no response from Boeing. I will complete this publication when the preliminary report is published...
Link to the original post on Quora
https://fr.quora.com/profile/Jean-Phili ... _type=post
Cyrano
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Re: Civil Aviation Development & Discussion

Post by Cyrano »

^^^ JP Brunet in the comments says the source was Israel Times, but they scrubbed that article. It's available on
https://alyaexpress-news.com/une-goupil ... e_vignette

May be this is fake news. In which case apologies in advance.
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How did they figure out that the captain seat moved ? That wasn’t in the AAIB report
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This was posted on 7 th july on Quora, before the preliminary report was released.
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Great find, many thanks! Given that input,

Investigation into LATAM 787 nosedive reveals possible cockpit pilot seat fault
https://www.aerotime.aero/articles/lata ... seat-fault

FAA requires inspection of Boeing 787 pilot seats after mid-air dive injured more than 50
https://www.cbsnews.com/news/faa-requir ... lot-seats/
Federal safety officials are requiring inspections of cockpit seats on Boeing 787 Dreamliners after one of the jets went into a dive when the captain's seat lurched forward without warning and disconnected the plane's autopilot system.

Within days of the incident, Boeing recommended that airlines look at the cockpit seats on 787s for loose caps on the switches and told them how to turn off power to the motorized seats.

The FAA said it has received four other reports from Boeing of cockpit seats moving when not intended to, including one in June.
https://www.motorbiscuit.com/faa-boeing ... ts-faulty/

The Federal Aviation Administration is looking into more than 700 Boeing 787 commercial airplanes for possible defective pilot seat switch caps or covers. The captain or first officer seat could unintentionally move, shutting off autopilot and leading to unexpected dive behavior mid-flight.
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https://simpleflying.com/faa-boeing-787 ... directive/

The Federal Aviation Administration has mandated an inspection of all Boeing 787 aircraft worldwide for switches responsible for the movement of the pilots’ seats in the cockpit. This relates to the LATAM Dreamliner incident in which the aircraft faced a sudden drop after the captain’s seat inadvertently moved forward.

Boeing 787 Dreamliner operators around the world have been asked by the Federal Aviation Administration (FAA) to inspect the seats of the captain and first officer on all three 787-8, 787-9, and 787-10 types for missing or cracked rocker switch caps or for cracked switch cover.

Airlines operating these planes have been asked to complete inspections within 30 days and perform any required corrective actions. According to Reuters, the directive affects 158 planes in the United States and 737 planes worldwide.
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Added: presumably, if captain seat movement was relevant, the preliminary report would mention it. In the final report one would expect a definite statement that inadvertent movement of the captain's seat was not detected.
Last edited by A_Gupta on 14 Jul 2025 17:55, edited 1 time in total.
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If, and that's a big IF, such a seat malfunction happened in this case, it will not be recorded on the DFDR. Perhaps the CVR may have some clues, and may be the cockpit debris but the chances are very very slim given the fireball that occurred after the crash.
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There is a fake news item that covers the pilot seat scenario, published June 25th
https://charlesokogene.com/2025/06/25/p ... t-reveals/
A faulty locking mechanism in the captain’s seat led to the deadly Air India Boeing 787 crash that killed 270 people, a preliminary report has revealed.

The investigation found that the pilot’s seat slid backwards during takeoff, causing the captain’s hands to unintentionally pull the throttle levers to idle.

This sudden loss of engine thrust just seconds after liftoff caused the plane to stall and crash into a nearby building housing medical workers.

According to the report, the co-pilot’s attempt to regain control was blocked by the captain’s reclined position.

Key cockpit data showed:

+12 seconds: Seat slides back

+15 seconds: Co-pilot shouts, “We’re losing thrust!”

Investigators also noted the absence of key safety features in the 787’s throttle system, such as reverse-motion protection and weight-based lockouts.

In response, the FAA and EASA have ordered urgent inspections of all Boeing 787 pilot seats.

Air India has grounded 12 planes with similar maintenance records, and Boeing has promised a seat redesign by 2026.

The crash killed passengers, crew, and residents in the building. A British national is the sole survivor.

The final report is due in July, with authorities promising stricter inspections and global aviation safety reforms.
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Post by vera_k »

There is this bit in the preliminary report that *may* align with what was posted earlier.

Doesn't make sense to me. Why would the thrust levers be found at idle and that movement not be recorded in the EAFR data?
Is it possible to move them easily such that they get into the idle position due to the force of the impact?
The thrust lever quadrant sustained significant thermal damage. Both thrust levers were found
near the aft (idle) position. However, the EAFR data revealed that the thrust levers remained
forward (takeoff thrust) until the impact.
Possible then that the report includes the fuel switches and limited CVR conversation as a red herring while continuing to investigate along other lines.
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How the AIR INDIA Kanishka plane (1985) was found and important items were recovered:

https://youtu.be/byNJ6g1JVqY
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