The black boxes from Air india disaster.

[si_c]

The video never indicated a strike of any kind as you'd have seen the results.

It's a system failure, I am sure of it and the thing of the fuel vapourising is fairly credible.

I expect to be proven wrong however.

There are a number of issues from what I've been reading - a few engineering sources have discounted the possibility of it being an issue with vapourlocking but it is certainly one of the more popular/credible theories. Other options are that the plane was right at the edge of it's operating environment - altitude, plane weight and weather conditions were somewhat borderline apparently - there was a headwind which was providing lift and the plane left the runway only just above it's stall speed so if the headwind had ceased at the wrong moment then it could have caused a stall.

Ultimately we'll only find out when the investigation concludes, at the moment it's just guessing.

 

[Jameshow]

There are a number of issues from what I've been reading - a few engineering sources have discounted the possibility of it being an issue with vapourlocking but it is certainly one of the more popular/credible theories. Other options are that the plane was right at the edge of it's operating environment - altitude, plane weight and weather conditions were somewhat borderline apparently - there was a headwind which was providing lift and the plane left the runway only just above it's stall speed so if the headwind had ceased at the wrong moment then it could have caused a stall.

Ultimately we'll only find out when the investigation concludes, at the moment it's just guessing.

But that would imply that there is no safety margin, and that aircraft when loaded to max capacity are like a mini 850 going up a hill??

 

[Regular.Cyclist]

There was a ‘technical issue’ the other day on Air India flight 315, another 787. Turned out to be a fuel filter alarm.

 

[Bonefish Blues]

All of which is complete speculation, of course, because we simply don't know at this point.

One of, if not the most respected commentators is Juan Brown (his youtube channel is here: https://www.youtube.com/@blancolirio/videos) He's gone no further than the facts available to us at the moment, publishing 2 videos covering it - the latter confirming deployment of the RAT (Ram Air Turbine) and the context around when it can be deployed. Worth a watch:


View: https://youtu.be/MPk31EhtakE?si=fgZEYaYSXooK9K30

 

[Bonefish Blues]

The must be an interim report within 30 days under international rules, so it won't be long before we have an inkling

Link here

https://aaib.gov.in/What's New Assets/Preliminary Report VT-ANB.pdf

In short, one pilot switched the fuel off for both engines in quick succession, then denied he'd done it. By the time the switches were turned back on it was too late.

 

[Beebo]

Very odd.

 

[markemark]

Link here

https://aaib.gov.in/What's New Assets/Preliminary Report VT-ANB.pdf

In short, one pilot switched the fuel off for both engines in quick succession, then denied he'd done it. By the time the switches were turned back on it was too late.

Not quite. They were cut off but we don’t know that one of the pilots did it. Could be faulty switches. Could be faulty wiring. Could be a pilot.

 

[Bonefish Blues]

Not quite. They were cut off but we don’t know that one of the pilots did it. Could be faulty switches. Could be faulty wiring. Could be a pilot.

The design is such that they have positive detents to prevent their accidental operation. The switches are not reported as faulty in the interim report. If it was 'faulty wiring' then the black box record of each switch being turned off in sequence within a second of each other would be an incorrect system record, which is rather unlikely. The switches are also on separate circuits, so their failing within a second of each other, and then switching back on - in conjunction with the voice recording of one pilot questioning the other all indicate human operation.

Everything points to manual intervention, both in their switching off - overcoming the detents on each switch sequentially, and similarly on switching back on c10 secs later (the design means it's almost impossible to us both switches together)

Just as a final thought - if there had been any reasonable suspicion that this was a system of electrical failure, no matter how unlikely, 787s would have been grounded, or at least subject to an urgent update. Neither has happened.

 

[Beebo]

It does seem to point to a deliberate act by one of the pilots.

The switches require a dual movement, they have to be pulled out and twisted, So it would be impossible to turn both switches accidentally.

 

[Mad Doug Biker]

Sobering stuff and reminds me a bit of the German guy who crashed his plane full of passengers into the side of a mountain.

 

[Illaveago]

So one pilot was having a bad day and the other a very bad day!

 

[Bonefish Blues]

It does seem to point to a deliberate act by one of the pilots.

The switches require a dual movement, they have to be pulled out and twisted, So it would be impossible to turn both switches accidentally.

Juan Brown, who I've linked before, raises the possibility, based on the Report, that it might possibly have been accidental. There was an advisory on those switches in 2018, to check their operation*, and particularly that the detent was operating as designed. He speculates that there might be a scenario where one pilot was covering the throttles and the switches were faulty, and they jogged both switches to off. That doesn't explain the sequential nature of the cut-off (i.e. the 1 second between each operation) I think it's an unlikely scenario, but pending further investigation (if possible) of the switches, he's right to put it out there.


View: https://youtu.be/wA_UZeHZwSw?si=s3tmmURjGbVJeJad


*Not done on this plane. Faulty switches were not reported by the pilots who operated this aircraft in the intervening years.

 

[wiggydiggy]

Sobering stuff and reminds me a bit of the German guy who crashed his plane full of passengers into the side of a mountain.

View: https://admiralcloudberg.medium.com/the-madness-in-our-methods-the-crash-of-germanwings-flight-9525-and-our-broken-aeromedical-system-5b95abd4fe6d


Excellent write up of that, and it's exact causes. I regularly read that authors articles as they are excellent.

 

[markemark]

The design is such that they have positive detents to prevent their accidental operation. The switches are not reported as faulty in the interim report. If it was 'faulty wiring' then the black box record of each switch being turned off in sequence within a second of each other would be an incorrect system record, which is rather unlikely. The switches are also on separate circuits, so their failing within a second of each other, and then switching back on - in conjunction with the voice recording of one pilot questioning the other all indicate human operation.

Everything points to manual intervention, both in their switching off - overcoming the detents on each switch sequentially, and similarly on switching back on c10 secs later (the design means it's almost impossible to us both switches together)

Just as a final thought - if there had been any reasonable suspicion that this was a system of electrical failure, no matter how unlikely, 787s would have been grounded, or at least subject to an urgent update. Neither has happened.

I get all that. But the report didn’t say the pilot did it. Everybody is drawing a very obvious conclusion and there’s little to no evidence to contradict it. But the report didn’t say the pilot switched the off.

 

[Bonefish Blues]

I get all that. But the report didn’t say the pilot did it. Everybody is drawing a very obvious conclusion and there’s little to no evidence to contradict it. But the report didn’t say the pilot switched the off.

Air accident reports don't make statements like that for long-established reasons.

It is clear from the Interim Report that it was a human hand that intervened - indeed we have a first-hand witness* who is reported to have asked the other pilot why did he cutoff (not if)

*via the cockpit voice recorder, not fully transcribed in the report.