Talk:Air India Flight 171: Difference between revisions

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:”’Exclude:”’ This is similar to what we were discussing in [[Talk:Air_India_Flight_171#Possible_Sources]] where a different lawyer put forth, without any evidence, that a software bug shut down the engines. She also has been involved in lawsuits against Boeing on behalf of victims’ families. The only way I would run this stuff is if there are RS which rebut these theories as fringe, speculative, ill-informed, etc. — [[User:Xan747|Xan747]] ([[User talk:Xan747|talk]]) 16:25, 14 September 2025 (UTC)

:”’Exclude:”’ This is similar to what we were discussing in [[Talk:Air_India_Flight_171#Possible_Sources]] where a different lawyer put forth, without any evidence, that a software bug shut down the engines. She also has been involved in lawsuits against Boeing on behalf of victims’ families. The only way I would run this stuff is if there are RS which rebut these theories as fringe, speculative, ill-informed, etc. — [[User:Xan747|Xan747]] ([[User talk:Xan747|talk]]) 16:25, 14 September 2025 (UTC)

:Agree with you. Paraphrasing a retired Boeing expert on PPrune, the engines are designed to keep running even on gravity fuel flow if needed. There is no likely way for the engines to stop other than putting switches on CUTOFF. It is unlikely that an electrical glitch would impact the engines, because designers want the engines to keep running unless commanded off. [[User:TBILLT|TBILLT]] ([[User talk:TBILLT|talk]]) 03:20, 1 October 2025 (UTC)

It has been reported on Twitter/X that the head of the American FAA has stated that the movement of the fuel cutoff switches does not seem to be a mechanical issue. Are there any better sources reporting this? He apparently said it to reporters, so it is likely to be reported somewhere. Mjroots (talk) 05:54, 26 July 2025 (UTC)[reply]

At least it should be quoted exactly as “we can say with a high level of confidence is it doesn’t appear to be a mechanical issue with the Boeing fuel control unit”, not that “FAA has stated that the movement of the fuel cutoff switches does not seem to be a mechanical issue”, as it is not clearly stated that the switches are a component of the fuel control unit. However, the consensus seems to be that the readers can make their own conclusion based on the facts already presented in the article. IlkkaP (talk) 10:16, 26 July 2025 (UTC)[reply]
NBC is reporting it and extensively quotes him by name:
“We can say with a high level of confidence is it doesn’t appear to be a mechanical issue with the Boeing fuel control unit,” Bryan Bedford, the FAA’s administrator, told reporters on the sidelines of an air show in Wisconsin. He said FAA employees had taken the units out, tested them and had inspectors get on aircraft and review them. “We feel very comfortable that this isn’t an issue with inadvertent manipulation of fuel control,” he said.
The initial reporting seems to be Reuters, but that is paywalled for me (though I was able to read the entire thing in a different browser).
So, not an anonymous source, who is an official of an investigating agency, quoted by a reputable wire news agency: I feel quite comfortable putting direct quotes with attribution into the article. Xan747 (talk) 19:08, 26 July 2025 (UTC)[reply]

Agree on the conclusion but we cannot put in the article that FAA administrator “feels very comfortable this isn’t an issue with inadvertent manipulation of fuel control”. IlkkaP (talk) 19:28, 26 July 2025 (UTC)[reply]

The administrator with direct knowledge of his own agency’s investigation of the relevant aircraft parts and flight data, who is on the record by name, is quotable *with attribution* in my book. But, I’d put it in the Reactions section, not Investigation, since it is not yet part of an official report. And I’d quote him directly instead of paraphrasing so that his exact language is preserved. Xan747 (talk) 19:35, 26 July 2025 (UTC)[reply]
Well hmm. On review, it is not clear to me whether the FAA had access to the parts from the incident aircraft, or if they were testing factory parts of the same type. The tipoff is He said FAA employees had taken the units out, tested them and had inspectors get on aircraft and review them. No way they got on the incident aircraft to do this. Xan747 (talk) 19:40, 26 July 2025 (UTC)[reply]
I have now added information regarding fuel control switch inspections according to a primary source published by air india themselves Prothe1st (talk) 18:33, 8 August 2025 (UTC)[reply]

And I have just reverted it because you copied it straight from the press release. It’s also not germane to the topic of this thread, which is the FAA conclusion there was no mechanical fault in the switches on the incident aircraft. Xan747 (talk) 18:35, 8 August 2025 (UTC)[reply]

Should the information still be added to this article? Prothe1st (talk) 18:42, 8 August 2025 (UTC)[reply]

It certainly doesn’t require a subsection of its own, and doesn’t belong to the Investigation section. If somewhere, a single sentence at the end of the Aftermath section. IlkkaP (talk) 18:52, 8 August 2025 (UTC)[reply]

Agreed. And here is a New York Times article to cite. Xan747 (talk) 18:54, 8 August 2025 (UTC)[reply]

I added the information to the article, with both NYT and Air India as sources (as NYT is apparently behind paywall) IlkkaP (talk) 07:12, 9 August 2025 (UTC)[reply]

Article currently reads in part both engines losing thrust after their fuel control switches moved from RUN to CUTOFF. But the timing for this seems unclear. The RAT deployed seconds before the switches were moved. Andrewa (talk) 10:43, 10 August 2025 (UTC)[reply]

How do you make that conclusion? The preliminary report states:
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.
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 IlkkaP (talk) 10:55, 10 August 2025 (UTC)[reply]

The event that interests me is the initial deployment of the RAT, as this indicates that both engines were already shutting down at that time. That and nothing else initiates automatic deployment of the RAT on this model of aircraft. The supply of hydraulic power is a later event than the triggering of RAT deployment. I don’t see the timing of this later event as significant. Do you? What does it tell you?
But if the engines were already shutting down at the time the fuel cutoff switches were operated, as the timing of the RAT deployment indicates, that tells me that something other than the operation of the switches caused the engines to start to shut down. Which is a very important thing to know, don’t you think?
Our article stated that the moving of the switches preceded the engines losing thrust. This is also a critical piece of information if true. But the evidence is that it’s not true. Andrewa (talk) 10:02, 11 August 2025 (UTC)[reply]

You misinterpret the preliminary report. IlkkaP (talk) 10:06, 11 August 2025 (UTC)[reply]

How? I didn’t think I was quoting it at all. Andrewa (talk) 22:00, 11 August 2025 (UTC)[reply]

On what basis do you conclude then “But if the engines were already shutting down at the time the fuel cutoff switches were operated, as the timing of the RAT deployment indicates”? IlkkaP (talk) 02:09, 12 August 2025 (UTC)[reply]

Please note the if. It’s the antecedent of a conditional statement, and you’re only citing half of that statement, which makes your question nonsensical. Andrewa (talk) 21:41, 12 August 2025 (UTC)[reply]

Let’s cite the other half as it is more relevant in this context: “Our article stated that the moving of the switches preceded the engines losing thrust. This is also a critical piece of information if true. But the evidence is that it’s not true.”
What is the “evidence” you are referring to? IlkkaP (talk) 02:49, 13 August 2025 (UTC)[reply]

This is actually a fair point; p. 14 of the report reads The CCTV footage obtained from the airport showed Ram Air Turbine (RAT) getting deployed during the initial climb immediately after lift-off (fig. 15). If we interpret “immediately” to be one second or less, then it could indeed seem that the RAT deployed before either of the switches moved to CUTOFF. However, the next sentence reads 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. We know from this source that the RAT deploys in case of dual engine failure or all three hydraulic losing pressure. Our article implies that the RAT deployed at 08:08:47 and instantaneously began producing power, but in reality it probably takes the RAT a few seconds to spin up. Putting it all together, it is probably fine to interpret the six seconds between liftoff and RAT producing power as “immediate”.
Here is the timeline for reference:

08:08:39 liftoff
08:08:?? RAT deployed “immediately” after liftoff
08:08:42 max velocity / fuel switch 1 CUTOFF
08:08:43 fuel switch 2 CUTOFF
08:08:47 RAT began supplying hydraulic and electrical power
08:08:52 fuel switch 1 to RUN
08:08:54 APU inlet door opens
08:08:56 fuel switch 2 to RUN
08:09:11 end of EAFR recording

Xan747 (talk) 15:17, 11 August 2025 (UTC)[reply]

It is clear from the report that RAT deployed after the fuel switches were cut off. Otherwise there would be other cause than the fuel cut off for engines losing thrust that would have been mentioned in the report. Agree that the word “immediately” is confusing in the report, but it is used in connection to the CCTV footage, not EAFR data. IlkkaP (talk) 15:26, 11 August 2025 (UTC)[reply]

Agree that this is what the report says. But it is a primary source and our article should not uncritically repeat its controversial claims. Andrewa (talk) 06:56, 12 August 2025 (UTC)[reply]

I would argue that the Preliminary report is actually a secondary source, as it provides thought and reflection based on primary sources, generally at least one step removed from an event. It contains analysis, evaluation, interpretation, or synthesis of the facts, evidence, concepts, and ideas taken from primary sources. IlkkaP (talk) 07:06, 12 August 2025 (UTC)[reply]

What are these primary sources? Andrewa (talk) 07:23, 12 August 2025 (UTC)[reply]

The CCTV footage for example IlkkaP (talk) 07:26, 12 August 2025 (UTC)[reply]

Which is not a source for the claim at all, as it does not show the order of these events, and no reliable source claims that it does. Andrewa (talk) 21:34, 12 August 2025 (UTC)[reply]
OK… looking at that timeline, it seems that the RAT deployed at a time that is uncertain, but is before the operation of the fuel switches, is that correct? Andrewa (talk) 03:01, 12 August 2025 (UTC)[reply]

No, we don’t know that. By the letter of the report, the RAT could have deployed any time between liftoff at 08:08:39 and when the EAFR shows it beginning to produce power at 08:08:47. Apologies for not more clearly indicating that uncertainty in the timeline. But as I said before, “immediately after takeoff” could reasonably be interpreted as “a few seconds after takeoff”, and I think that is the most reasonable interpretation. Interested as to why you consider this “controversial”. I’ve not seen any RS questioning that particular detail since the preliminary report was released. Xan747 (talk) 14:32, 12 August 2025 (UTC)[reply]

I’m not talking about the report, purely about your timeline, which states
08:08:?? RAT deployed “immediately” after liftoff
08:08:42 max velocity / fuel switch 1 CUTOFF
Now you don’t give a reason for having the events in this order, nor a time for the RAT deployment. Are you now saying that this order may also be questionable? Andrewa (talk) 21:36, 12 August 2025 (UTC)[reply]

08:08:39 liftoff
08:08:39 earliest RAT could have deployed per the letter of the report (“immediately after takeoff”)
08:08:42 max velocity / fuel switch 1 CUTOFF
08:08:43 fuel switch 2 CUTOFF
08:08:43 earliest RAT likely deployed per RS (“automatically deploys in flight when both engines lose power or if all three hydraulic systems register critically low pressure”)
08:08:47 latest RAT could have deployed
08:08:47 RAT began supplying hydraulic and electrical power
08:08:52 fuel switch 1 to RUN
08:08:54 APU inlet door opens
08:08:56 fuel switch 2 to RUN
08:09:11 end of EAFR recording
I consider it most likely the RAT deployed between 08:08:43 and 08:08:47 in response to both fuel switches moving to CUTOFF and subsequent dual-engine shutdown. The RAT deploying before the EAFR registered fuel switch CUTOFF events would point toward some sort of mechanical, electrical or software issue. Had that been the case, or even suspected, the report would have almost certainly mentioned it. I don’t see anything “controversial” about this, or any reason to change how the article reads. Xan747 (talk) 14:50, 13 August 2025 (UTC)[reply]
Additionally, all of the timed events in the relevant section (12) of the report are given in chronological order. The pilot asking why the other cut off fuel, the other pilot denying it, and the text about the CCTV footage showing RAT deployment “immediately after lift-off” both fall between the 08:08:42-43 fuel switch cutoffs and the 08:08:47 RAT producing power timestamps. This very strongly suggests that the AAIB finding should be interpreted as RAT deployment as a response to the fuel switches moving to CUTOFF, not some unspecified event causing engine shutdown prior to movement of same. Xan747 (talk) 16:07, 13 August 2025 (UTC)[reply]

The exact RAT timing is not disclosed but presumably the detailed data exists on the as yet undisclosed Data Recorder data and/or CCTV videos. The AAIB preliminary report strongly suggests it was the movement of both fuel switches to CUTOFF that caused the RAT deploy. There are several vocal YouTubers saying that they estimate/believe the AAIB preliminary report was incorrect re: RAT timing and crash cause, but I currently personally put those YouTubers in the zero proof/contrarian category. TBILLT (talk) 02:33, 11 September 2025 (UTC)[reply]

I hope you don’t mind, but I moved your comment down here into chronological order. I think we are in agreement. We of course could never use YouTube pundits on Wikipedia, but some I have seen have really done themselves and their viewers a disservice trying to second-guess the AAIB on this. Xan747 (talk) 02:52, 11 September 2025 (UTC)[reply]

No prob. I know, some are fellow citizen investigators from MH370 studies, that I do not always agree with. I hope we eventually see all of the raw data so we can sort out false accusations vs. facts. But there is no guarantee of transparent public disclosure. The obvious thing for AI#171, aside from the Prelim Report which was surprising in its candor re: preliminary cause, otherwise there has been terrible lack of transparency, which promotes rumors, accusations etc. In the USA we’d have NTSB giving detailed daily reports, but many other countries want secrecy, whereas secrecy does not work as well in today’s social media environment. TBILLT (talk) 17:42, 11 September 2025 (UTC)[reply]

– Mary Schiavo (former U.S. Department of Transportation Inspector General and aviation attorney) warned that the crash of Air India Flight AI-171 may have been caused by a **computer-triggered engine thrust rollback** — a known Boeing 787 software malfunction previously investigated by the U.S. National Transportation Safety Board (NTSB) ([latest.sundayguardianlive.com](https://latest.sundayguardianlive.com/investigation/boeing-787-software-may-have-caused-ai-crash-aviation-expert)).
—Andrewfromx (talk) 16:30, 8 August 2025 (UTC)[reply]

To me, doesn’t sound credible as a cause, as not mentioned in the preliminary report which I find more trustworthy than the Indian newspaper referred. IlkkaP (talk) 17:48, 8 August 2025 (UTC)[reply]
I’ll add that Schiavo has no official role in the investigation, and is talking about a software issue for which–according to her own statement–a corrective action was already issued. This is just more of the same type of speculation from the sidelines of the type we’re already not including. Xan747 (talk) 19:10, 8 August 2025 (UTC)[reply]
I would put forth all the garybpilot videos like https://www.youtube.com/watch?v=CCFfibo9uR4&pp=ygUVMTcxIGFpIGNyYXNoIHNvZnR3YXJl https://www.youtube.com/watch?v=VswFVpyg5ew https://www.youtube.com/watch?v=2s4IqA3xR20 Andrewfromx (talk) 08:26, 11 August 2025 (UTC)[reply]

YouTube is even worse than your previous suggestion as most videos are self-published (meaning there is no editorial oversight). YouTube videos can be considered reliable when taken from a channel that is verified to belong to a credible news agency. The videos you cite do not fit that description. See WP:RSPSOURCES for more information. Xan747 (talk) 15:28, 11 August 2025 (UTC)[reply]
Prior to the Preliminary Report, Mary Schiavo was referring to a hypothetical failure in the TCMA (thrust control) system that had caused a landing issue in one prior case. Now that we have the Preliminary Report, there is no mention of erroneous activation of the TCMA system, and the fact that both engines restarted successfully before the crash would suggest TCMA system was not involved, and furthermore the TCMA system would not be expected to be engaged off the ground and during takeoff. TBILLT (talk) 02:53, 11 September 2025 (UTC)[reply]

Prelim AAIB report issued within 30 days per ICAO guidelines on July 12 (not July 8 in article). TBILLT (talk) 03:16, 11 September 2025 (UTC)[reply]

Thanks for the notice, it has now been corrected IlkkaP (talk) 03:28, 11 September 2025 (UTC)[reply]

Recently some editors have added a link to https://www.independent.co.uk/asia/india/air-india-crash-theories-what-caused-lawyer-boeing-b2825181.html which presents a theory that a leakage from the plane’s water pipes could have caused FADEC to reset and therefore cutting off the engines.

This theory is inconsistent with the preliminary report as according to the report “Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another”. However, while FADEC reset might cause the engines to turn off, it doesn’t cause movement of the fuel cutoff switches in the cockpit.

Furthermore, the fringe theory is presented by a lawyer seeking damages from Boeing. Clearly he doesn’t understand how aircraft systems work. IlkkaP (talk) 14:35, 14 September 2025 (UTC)[reply]

Exclude: This is similar to what we were discussing in Talk:Air_India_Flight_171#Possible_Sources where a different lawyer put forth, without any evidence, that a software bug shut down the engines. She also has been involved in lawsuits against Boeing on behalf of victims’ families. The only way I would run this stuff is if there are RS which rebut these theories as fringe, speculative, ill-informed, etc. — Xan747 (talk) 16:25, 14 September 2025 (UTC)[reply]
Agree with you. Paraphrasing a retired Boeing expert on PPrune, the engines are designed to keep running even on gravity fuel flow if needed. There is no likely way for the engines to stop other than putting switches on CUTOFF. It is unlikely that an electrical glitch would impact the engines, because designers want the engines to keep running unless commanded off. TBILLT (talk) 03:20, 1 October 2025 (UTC)[reply]

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