Civil Aviation Development & Discussion

[srin]

If only they mandate video recording of cockpit…

[A_Gupta]

Just how much would inspection of the cockpit fuel switches in an airline's Boeing fleet cost?

[vera_k]

Not substantial, and definitely not material. If your flight has ever been delayed due to a "technical issue" you've seen that airlines do work on the planes as a routine part of daily operations. This would get added to that list.

This report from ToI today also confirms that the fuel control switches were previously replaced in 2023 since they are an integral part of the throttle control module.

AI 171 crash aftermath

[jrjrao]

Another exclusive in the WSJ. Today's paper:


New Details in Air India Crash Probe Shift Focus to Senior Pilot

Black-box recording and report details indicate the flight’s captain switched off fuel flow to engines

[vera_k]

AAIB is pushing back on the WSJ report.

AAIB slams irresponsible conclusions

[Amber G.]

AAIB is pushing back on the WSJ report.

AAIB slams irresponsible conclusions

WSJ Aritcle- (New Details in Air India Crash Probe Shift Focus to Senior Pilot)
summary:
-New cockpit‑voice recordings and flight‑data evidence now suggest Captain Sumeet Sabharwal may have switched both engine fuel-control switches to “cutoff” shortly after takeoff from Ahmedabad—causing a loss of thrust and ultimately triggering the crash .

- The first officer, Clive Kunder, is heard sounding panicked, asking “why” the switches were moved; the captain responds calmly and seemingly denies the action .

- At this stage, investigators haven’t concluded whether this was an intentional act or a mistake; U.S. authorities are considering whether criminal charges are warranted if deliberate action is confirmed.

AAIB has urged caution, stating conclusions are premature and criticizing what it called “irresponsible” media speculation ..

.

[Tanaji]

How are such details being leaked to the media?

[chetak]

AAIB is pushing back on the WSJ report.

AAIB slams irresponsible conclusions

vera_k ji,

Do we discern a difference in the approaches (and thereby the diverging interests) of the FAA and the NTSB, with one being openly partisan to the interests of the amriki deep state asset, while the other proceeds with the caution warranted by the gravity of the situation.

The AAIB is right to callout the WSJ, toilet, et al but at least for the moment, aren't the AAIB and the NTSB in the same corner

[Hriday]

https://www.businesstoday.in/india/stor ... e_vignette

Some excerpts,

Top aviation expert: 'Boeing Dreamliner software can cut fuel without pilot input, has happened twice'

Aviation attorney and former US Department of Transportation Inspector General Mary Schiavo has cautioned against rushing to blame the pilots in the Air India crash. She pointed out that the Boeing Dreamliner has a system capable of cutting fuel to the engines on its own.
...
Schiavo pointed to prior incidents involving the same aircraft model where onboard systems, without pilot input, cut fuel to the engines mid-air. She cited a 2019 All Nippon Airways incident where a Boeing 787's system mistakenly shut off fuel mid-air after misjudging that the aircraft had already landed. "That system — TCMA — has already been faulted in a prior incident. It can and will cut the thrust to both engines if it malfunctions," she said.
...

She also referred to a more recent case involving a United Airlines Dreamliner flight between Washington DC and Nigeria. "The plane itself put the plane into a nose dive. There was a thrust issue, there was an engine issue, and the plane experienced some deviations," she said.
..
The TCMA is a system that the FAA mandated so that the plane itself can assess when it needs to cut back the power. And that is tied in with the flight controllers, which are on both of the engines," she explained.
..
"In about 75% of the cases the pilots are blamed and in many cases… we’ve been able to disprove that," she said.

[vera_k]

Do we discern a difference in the approaches (and thereby the diverging interests) of the FAA and the NTSB, with one being openly partisan to the interests of the amriki deep state asset, while the other proceeds with the caution warranted by the gravity of the situation.

Conjecture, but any leaks would come from the NTSB as they are part of the investigation team. The FAA is not directly involved. However, an article can well be published on second or third hand information.

This daily mail article today attributes to two unnamed Western sources. So not from within the AAIB team.
Eerie words

[chetak]

महात्मा गांधी राष्ट्रपिता नहीं है, RTI में सरकार का खुलासा..

Mahatma Gandhi is not the Father of the Nation, government reveals in RTI...

WATCH VIDEO

[A_Gupta]

महात्मा गांधी राष्ट्रपिता नहीं है, RTI में सरकार का खुलासा..

Mahatma Gandhi is not the Father of the Nation, government reveals in RTI...

WATCH VIDEO

Netaji was the first to call him that.

[sanjayc]

Gandhi's pernicious influence on the mind of the masses has to go down if Hindu society has to survive. His name has to be purged from the Hindu memory. His philosophy is nothing but glorified suicide. A beginning has to be made by removing his face from our currency.

[chetak]

WATCH VIDEO

Netaji was the first to call him that.

A_Gupta ji,

It makes no never mind. May be Netaji was being sarcastic because ghundhy disliked him and manoeuvred Netaji out of the congress to accommodate his own favourites

It was also the britshits who called him that and treated him as such because they themselves realized and admitted as much that he was worth at least two divisions to them.

That was strategy, mind games and psychological manipulation of the society at large, a tactic that the britshits employed by cleverly using him to enhance their colonial power, and maintain law and order in India.

He was the one who "approved" the use of Indian troops in WWII and there was no significant opposition to this, because he was used as the front to project the harmonious cooperation. This resulted in the butchering, maiming and grievously injuring of tens of thousands of Indians, especially when India had no dog in a fight that was taking place in another, very different, and faraway world, for reasons that did not concern the Indians in any way.......

That was true ahimsa, no ..........


But let's not continue with this on this thread

The original post on this thread was my inadvertent mistake. Apologies

The birds of prey will arrive soon enough

[Prem Kumar]

...

He was the one who "approved" the use of Indian troops in WWII and there was no significant opposition to this, because he was used as the front to project the harmonious cooperation. This resulted in the butchering, maiming and grievously injuring of tens of thousands of Indians, especially when India had no dog in a fight that was taking place in another, very different, and faraway world, for reasons that did not concern the Indians in any way.......

That was true ahimsa, no ..........

He was the consummate coward & hypocrite. Preached Ahimsa when Indians took up arms against the Brits. But exhorted Indians to take up arms on behalf of the Brits

If that doesn't make him a traitor, I don't know what does

P.S. Was tempted to add one more before the birds of prey arrived

[gakakkad]

And he was a pedo . Mahatma mohandas Epstein.

[tandav]

AI171 Engine fuel cutoff occured nearly immediately after take off. There is evidence that the takeoff took longer than usual. This may have triggered the TCMA to initiate automatic fuel cutoff as the aircraft transitioned to air.

The pilots realized dual engine shutoff had occurred and initiated engine relight procedure 6 seconds later by cycling the fuel cutoff switch as per standard procedures fighting

The Blackbox recorded the TCMA initiated dual engine shutoff and the subsequent pilot initiated engine relight

[Vayutuvan]

There is evidence that the takeoff took longer than usual.

Genuine doubt. What are all the circumstances which delay the takeoff of a plane? My guess is that pilots didn't something on time or the engines were not getting enough fuel or some (discrete) contaminant was in the fuel which throttled the flow momentarily.

CT alert:

Is it possible to put a solid plug (something like stent) in the piping that would slowly dissolve into the fuel and contaminate the fuel? A cleverly calculated and designed plug can make this happen a the most critical time. Obviously it had to be done by someone who knows all the parameters of the Dreamliner engine - pipe width, flux, how much contaminant required to trigger a malfunction etc.

But Occam's razor says there may be simpler explanation.

[pravula]

Hotter temp, heavier loadout, wind direction...Could be anything...

[tandav]

https://www.businesstoday.in/india/stor ... 2025-07-17

There is no other viable theory of crash given what we know from AAIB report.
1) TCMA or other SW/HW fuel shutoff (very high probability)
2) Pilot Suicide (highly unlikely)

[nachiket]

Would the switches be accessible to

> a jumpseat passenger in the cockpit, like a deadheading crew member
?

My guess is that (long time back I had a glance into a cockpit of a plane, pilot and copilot are seated such that, if anybody accesses any of the dials or switches they have to reach out from behind the pilot/co-pilot to do so. One or both would have noticed immediately that somebody else is trying to access the dashboard.

The reason I speculated about this is because this scenario actually happened once in an Alaska Airlines flight where a mentally disturbed off-duty pilot in the jumpseat who hadn't slept for 40 hours and was possibly on drugs attempted to pull the fire handles for the engines. If he had succeeded, that would have not only cut the fuel but also discharged the fire extinguisher making it impossible to restart the engines. Thankfully the pilots noticed him doing so and were able to stop him in time but it was very close. But that was a small Embraer 175. I don't know what would happen in a large B787 cockpit - whether the switches would be accessible to a jumpseater and if they are whether the pilots would notice especially in a high workload situation during takeoff.

But since there has been no news whatsoever since then about any jumpseat passenger this is very unlikely. So we are only left with the pilots themselves. Giving the pilots the benefit of the doubt I suppose it is possible that the pilot monitoring (which was the Captain I believe) absent-mindedly moved the fuel cutoff switches while trying to do something else entirely and it didn't even register in his mind. This would be similar to the Captain of Yeti airlines 691 who feathered the props instead of setting the flaps without even realizing it. This would explain the F/O's "panicked voice" once he realized what had happened and the captain's denial of having moved the switches since in his own mind he doesn't even remember touching them. The F/O would have been fully concentrating on flying the aircraft at this point with both hands on the control column and eyes on his primary flight display. So you would not expect him to figure out that the switches were moved for several seconds which is exactly what happened.

But this is a stretch. Pilot suicide theory is unfortunately the most likely scenario given the details released so far. This could change if the AAIB decided to release more info like the entire CVR transcript instead of just two sentences.

[Vayutuvan]

Hotter temp, heavier loadout, wind direction...Could be anything...

Yes, those are far simpler explanations and probably are the correct explanations (applying Ockham's razor).

[tandav]

Would the switches be accessible to

> a jumpseat passenger in the cockpit, like a deadheading crew member
?

My guess is that (long time back I had a glance into a cockpit of a plane, pilot and copilot are seated such that, if anybody accesses any of the dials or switches they have to reach out from behind the pilot/co-pilot to do so. One or both would have noticed immediately that somebody else is trying to access the dashboard.

Snip

But this is a stretch. Pilot suicide theory is unfortunately the most likely scenario given the details released so far. This could change if the AAIB decided to release more info like the entire CVR transcript instead of just two sentences.

Any reasons to discount the far more probable TCMA HW/SW fault?

[Ambar]

Snip

But this is a stretch. Pilot suicide theory is unfortunately the most likely scenario given the details released so far. This could change if the AAIB decided to release more info like the entire CVR transcript instead of just two sentences.

Any reasons to discount the far more probable TCMA HW/SW fault?

That argument doesn’t hold up. It’s based on a post by a U.S.-based aviation attorney who likely smells blood for litigation against Boeing. The TCMA system operates through independent EECs, with built-in redundancy precisely so that a malfunction in one engine doesn't impact the other. For TCMA to activate, the throttle must be at idle and the asymmetric thrust threshold exceeded. Even then, it does not cut fuel to both engines simultaneously each EEC makes that determination independently and only for its own engine.

You can read how it functions in Boeing's patent - https://patents.google.com/patent/US6704630B2/en

The lawyer cites two unrelated incidents. In the first, the aircraft was still on the ground. In the second, the thrust wasn't the issue the pilot’s seat unexpectedly shifted forward, causing them to push the control column and unintentionally pitch the nose down.

Let’s also be clear: neither DGMO, AAIB, NTSB, ICAO, nor Boeing has issued any technical or procedural advisories about this. Both the AI CEO and Air India stated yesterday that all 787s in their fleet have been inspected, and no faults were found with the fuel control switches. The investigators have access to the full CVR and FDR and all we have are speculative theories.

[A_Gupta]

Appeals not to speculate AAIB, NTSB
https://indianexpress.com/article/busin ... -10136202/

[Cyrano]

An interesting analysis. I too wondered re the photo in the preliminary report and how early the RAT was deployed.

[tandav]

An interesting analysis. I too wondered re the photo in the preliminary report and how early the RAT was deployed.

Its even more convincing evidence that Engines Quit simultaneously by a TCMA glitch. As per video above the RAT was definitely fully deployed at an altitude of 167 ft probably even earlier and by my assessment near the ground itself perhaps within 50ft of ground. The aircraft was ascending at 40 ft/s so the flight and was in air for 167 ft/40 ft/s = 4 seconds.

I strongly believe The Fuel Cutoff switches in the cockpit console were still in run position in the cockpit but the fuel had been cutoff by TCMA in the backend. The pilots followed protocol in restarting engine 1 by cycling (Run->Shutoff->Run Cycle) and subsequently engine 2 by cycling (Run->Shutoff->Run) after a few seconds when they later realized that not just 1 but both engines were inactive.

There is no startle effect as the American commentators are alluding too to support their pilot suicide nonsense.



The immediate 1+2 shutoff implies a TCMA failure more details below.

https://www.reddit.com/r/AskIndia/comme ... e%20AI171.