Air India crash

[Blueadventures]

There are reports now that the Captain had some health issues over recent years that took him from flying for some periods, and a family death had occurred, and he was cleared to fly again after that recent absence.

 

Also investigators will consider if the situation arose where the person switching the FCS to off sought to cover the action by asking the other why they moved the switches; such typically occurs in some crimes. Just one of many questions the investigation team may chase.

[danny_galaga]

This is a great write up from a crash investigator basically pointing out we are only at the moment seeing a preliminary report. There is not much we can yet surmise. Something I've been guilty of in this case. Pointing out for instance the pilots conversation in the report apparently regarding the fuel switches is out of context and paraphrased.

 

https://theconversation.com/was-the-air-india-crash-caused-by-pilot-error-or-technical-fault-none-of-the-theories-holds-up-yet-261102?utm_medium=article_native_share&utm_source=theconversation.com

Edited Monday at 11:08 AM by danny_galaga

[Roundsounds]

21 minutes ago, danny_galaga said:

This is a great write up from a crash investigator basically pointing out we are only at the moment seeing a preliminary report. There is not much we can yet surmise. Something I've been guilty of in this case. Pointing out for instance the pilots conversation in the report apparently regarding the fuel switches is out of context and paraphrased.

 

https://theconversation.com/was-the-air-india-crash-caused-by-pilot-error-or-technical-fault-none-of-the-theories-holds-up-yet-261102?utm_medium=article_native_share&utm_source=theconversation.com

What makes this a great write up? It makes statements contrary to the AAIB report. 

[onetrack]

I personally think it's disgraceful that so many people in so-called "authoritative positions", who should know better, are jumping on the "pilot suicide" bandwagon.

 

The figures bely their definitive, hard opinions. There have been maybe 10 pilot suicides in commercial aircraft in the last 30 or 35 years (taking out deliberate acts of aircraft terrorism such as 9/11) - with perhaps another half dozen crashes where the reason was never found, but suicide was on the suspicion list.

 

In contrast, in the same time frame, there have been hundreds of incidents, some resulting in major crashes, where inadvertent pilot error, mistakes in switch and controls selection by crew, major errors in following emergency procedures, and even distraction by crew members, or concentration on less important warnings resulted in the overlooking of major warning signals, occurred.

 

As a result, the chances of this crash being caused by a pilot suicide is a vastly less likelihood, than the likelihood of one of the range of crew errors mentioned above.

[Roundsounds]

On 13/7/2025 at 2:24 PM, kgwilson said:

I don't think it is obvious at all that the cutoff switches were moved in the cockpit. That may just have been an assumption by the pilot when power was lost and the other pilot said he didn't. This assumes the 2nd pilot was not planning a crash.

 

The reports states 

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. 

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.  

 

There are likely to be plenty of conspiracy theories going around but a software or system logic failure cannot be ruled out. If it was a system failure then over 1100 787s would be immediately grounded and that could put another nail in the Boeing & US Aviation industries coffin.

Maybe you should review what you’ve written against what you’ve quoted from the report. The report doesn’t say a signal to the fuel firewall shutoff valves caused them to close, it says the fuel cutoff switches transitioned from RUN to CUTOFF. There’s no suggestion of a software or system logic failure. 
Facts are both FCS weren’t moved from RUN to CUTOFF causing a loss of thrust. What is not know is how or why this occurred. 
To suggest a software fault caused the loss of thrust;

- ignores the report findings

- displays a lack of understanding of Air Transport Category aircraft design criteria.  

Edited Monday at 12:05 PM by Roundsounds

[danny_galaga]

1 hour ago, Roundsounds said:

What makes this a great write up? It makes statements contrary to the AAIB report. 

Which statements are they?

[BrendAn]

8 hours ago, onetrack said:

I personally think it's disgraceful that so many people in so-called "authoritative positions", who should know better, are jumping on the "pilot suicide" bandwagon.

 

The figures bely their definitive, hard opinions. There have been maybe 10 pilot suicides in commercial aircraft in the last 30 or 35 years (taking out deliberate acts of aircraft terrorism such as 9/11) - with perhaps another half dozen crashes where the reason was never found, but suicide was on the suspicion list.

 

In contrast, in the same time frame, there have been hundreds of incidents, some resulting in major crashes, where inadvertent pilot error, mistakes in switch and controls selection by crew, major errors in following emergency procedures, and even distraction by crew members, or concentration on less important warnings resulted in the overlooking of major warning signals, occurred.

 

As a result, the chances of this crash being caused by a pilot suicide is a vastly less likelihood, than the likelihood of one of the range of crew errors mentioned above.

An experienced pilot turns both switches off by mistake . I don't think so. And they can't be bumped off either as Juan stated.

[Thruster88]

A few points. 

 

Although not mentioned in the preliminary report, the cut off switch movements were likely recorded on the cockpit audio recorders. 

 

There is no mention of any engine change in either engine N1, N2, egt ect prior to the cutoff off switch movements that would have required any pilot memory action.

 

The only pilot actions required at that stage of flight is to retract under carriage and pitch for desired airspeed.

[kgwilson]

10 hours ago, Roundsounds said:

Maybe you should review what you’ve written against what you’ve quoted from the report. The report doesn’t say a signal to the fuel firewall shutoff valves caused them to close, it says the fuel cutoff switches transitioned from RUN to CUTOFF. There’s no suggestion of a software or system logic failure. 
Facts are both FCS weren’t moved from RUN to CUTOFF causing a loss of thrust. What is not know is how or why this occurred. 
To suggest a software fault caused the loss of thrust;

- ignores the report findings

- displays a lack of understanding of Air Transport Category aircraft design criteria.  

The transition from one state to another is reported via programs to the FDR (software). The reported transition is electro mechanical if induced by the pilot. It could also be induced by a short circuit in the wiring or switch itself. While highly unlikely it is still possible.

[facthunter]

There is NOTHING in those switches that could make the Lever change position.   nev

[spacesailor]

Unless those switches were not locked into that indented position. 

But left on the Ridge before  locked position!.

spacesailor

[onetrack]

41 minutes ago, spacesailor said:

Unless those switches were not locked into that indented position. 

But left on the Ridge before  locked position!.

spacesailor

If that were the case, the incorrect switch position would immediately be obvious to anyone in the cockpit - and the contacts for each position wouldn't be activated.

In addition, how could BOTH switches be left incorrectly located on the locking ridge? One, perhaps, but not both.

 

Just one switch left in an incorrect centre position would stand out even more than both being incorrectly positioned.

 

Edited yesterday at 02:37 AM by onetrack

[onetrack]

3 hours ago, kgwilson said:

The transition from one state to another is reported via programs to the FDR (software). The reported transition is electro mechanical if induced by the pilot. It could also be induced by a short circuit in the wiring or switch itself. While highly unlikely it is still possible.

Yes, a wiring short circuit could possibly activate one of the HPSOV's - but not both, they are totally independent switches, circuits and engine ECU's.

[BrendAn]

Pilot mental health in spotlight after Air India Flight 171 disaster©Daily Mail

Investigations into the Air India plane crash are looking into the pilots' medical records as it's claimed one of them had depression and mental health issues. Captain Sumeet Sabharwal, an experienced pilot with more than 8,200 hours in the cockpit, was piloting the Boeing 787 Dreamliner when it plummeted into a residential area, called Meghani Nagar, killing 241 people on board and claiming 19 more lives of those on the ground.

[BrendAn]

[BrendAn]

Pilot mental health in spotlight after Air India Flight 171 disaster

©REUTERSCaptain Mohan Ranganathan, a leading aviation safety expert in India, has revealed that 'several' Air India pilots had allegedly confirmed that the well-experienced pilot had suffered from poor mental health. Speaking to The Daily Telegraph , he claimed: 'He had taken time off from flying in the last three to four years. He had taken medical leave for that. Captain Sabharwal is also understood to have taken bereavement leave after the death of his mother, though it is believed by Mr Ranganathan that he had been 'medically cleared' by Air India prior to the fatal crash last month.

[spacesailor]

So ' lift and  turn ' 

what would happen if that turn didn't happen ?.

spacesailor

 

[facthunter]

"Turn' is viewed from the side. It's Badly described The switch  lever moves in an arc about a pivot point UP and DOWN. Nev

[onetrack]

An Indian pilot demonstrates the operation of the B787 fuel cutoff switches.....

 

 

[Thruster88]

In the above video the microphone picks up the sound of the switch movement quite easily. 

 

I guess it may be possible to move the switch somewhat more quietly. 

Edited yesterday at 08:48 AM by Thruster88

[Garfly]

Russ Niles of AvWeb adds this take:

 

 

Without Video, We'll Never Really Know - AVweb

AVWEB.COM

---

Will the real cause of the crash of Air India 171 ever be known?

 

Excerpt:

"As with everything else it seems, those switches feed wires that end up at a computer, which has the final decision on whether the simple opening or closing of a circuit can proceed. That little box, strapped unceremoniously to the main fan housing of the massive engine, controls all things to do with the fuel, including its sudden absence, a handy feature if it’s on fire but a disaster a few seconds after the mains have air under them. A solder joint on that control unit is prone to cracking and airlines were advised to replace them in 2021.

This plane was said to be up to date on all those sorts of maintenance advisories, so I assume it was done. But the working theory heading around the airline blogs and forums is that it’s possible that a cracked solder joint interrupted the current from the switches under the Gs of rotation to stop the fuel flow long enough to shut down both engines. As far-fetched as it seems, it introduces enough doubt to lay waste to all the other depressing scenarios being bandied about and the arguments that flow from there."

 

 

 

Edited 23 hours ago by Garfly

[Roundsounds]

5 minutes ago, Garfly said:

Russ Niles of AvWeb adds this take:

 

 

Without Video, We'll Never Really Know - AVweb

AVWEB.COM

---

Will the real cause of the crash of Air India 171 ever be known?

 

Excerpt:

"As with everything else it seems, those switches feed wires that end up at a computer, which has the final decision on whether the simple opening or closing of a circuit can proceed. That little box, strapped unceremoniously to the main fan housing of the massive engine, controls all things to do with the fuel, including its sudden absence, a handy feature if it’s on fire but a disaster a few seconds after the mains have air under them. A solder joint on that control unit is prone to cracking and airlines were advised to replace them in 2021.

This plane was said to be up to date on all those sorts of maintenance advisories, so I assume it was done. But the working theory heading around the airline blogs and forums is that it’s possible that a cracked solder joint interrupted the current from the switches under the Gs of rotation to stop the fuel flow long enough to shut down both engines. As far-fetched as it seems, it introduces enough doubt to lay waste to all the other depressing scenarios being bandied about and the arguments that flow from there."

 

 

 

The ignorant people who dream up this sort of rubbish obviously don’t understand the certification requirements for these types of airplane. 

[facthunter]

Apparently the CVR didn't. They reckon you'd need a camera to confirm it. We still have a fair idea..  Nev

[Roundsounds]

9 hours ago, kgwilson said:

The transition from one state to another is reported via programs to the FDR (software). The reported transition is electro mechanical if induced by the pilot. It could also be induced by a short circuit in the wiring or switch itself. While highly unlikely it is still possible.

Not to shut down both engines. The systems architecture ensures this cannot occur. 

[facthunter]

These aircraft microprocessors are just there to run a Programme defined by the LOGIC the designers have decided to build into it which has many FAIL SAFE aspects and backups making it more suited to being in an aircraft. Mt  Brother lectured at Uni On Computers  before everybody had one and said at the time HE wouldn't fly in a plane CONTROLLED by a computer.  Neither would I.

  These are very Limited application devices. Nothing much like computers in general. They are also good at reducing human error.  Nev