The black boxes from Air india disaster.

[DaveReading]

The stop/start of the fuel is the correct procedure to an engine failure (stall, fire etc). Apparently something pilots are trained to immediately and quickly akin to a reflex. Is it conceivable that there was a false warning for the engines and the pilots did what they’re trained to automatically do and restart them?

No.

If an engine fails on takeoff, attempting to restart it would be nowhere the list of recommended immediate actions. Flying the aeroplane is the priority.

If both engines on a twin fail on takeoff, we're in uncharted territory that simply isn't trained for.

 

[Psamathe]

Good grief! Complete anal speculum speculation! Nobody will know until the investigation is complete and then we probably won't know the full facts anyway! I don't think it's helpful to make assumptions at this stage.

For me it's not about my personal views but wanting all those planes taking-off today, tomorrow, etc. to not be at similar risk. Without speculating) if the switches can represent a risk easy and cheap to make all pilots aware of the risk whilst switches/guards are designed and tested.

If some other cause then sooner identified sooner steps to avoid put in place.

Ian

 

[albion]

https://news.sky.com/story/backlash...human-error-heres-what-experts-think-13395845
"The Ram Air Turbine (RAT), which deploys automatically when both engines fail and power drops below a threshold, was observed as deployed in CCTV footage when the aircraft was approximately 60ft above ground level," Mr Singh said.
"This suggests that the dual engine failure likely occurred before the official timestamp of 08:08:42 UTC, implying a possible discrepancy."
......
Mr Singh said it was also "of particular note" that the plane's emergency locator transmitter (ELT) did not send any signal after the crash.
"Was the ELT damaged, unarmed, mis-wired, or malfunctioning?" he said.
The report has generated more questions than answers on topics including human error, power source failures and mechanical or electrical malfunction.
The final report is expected to take a year. Meanwhile, families grapple with the unimaginable loss of loved ones in one of the worst disasters in India's aviation history

​

 

[Beebo]

Apparently the investigation team are bringing in “Aviation Psychologists” as part of the next phase.

Whilst I’m sure the investigation will be thorough they do seem to be pointing towards a deliberate act.


View: https://youtu.be/00ooqCuRoU8?si=K9wIuIGeI1twH9kF

 

[DaveReading]

https://news.sky.com/story/backlash...human-error-heres-what-experts-think-13395845
"The Ram Air Turbine (RAT), which deploys automatically when both engines fail and power drops below a threshold, was observed as deployed in CCTV footage when the aircraft was approximately 60ft above ground level," Mr Singh said.
"This suggests that the dual engine failure likely occurred before the official timestamp of 08:08:42 UTC, implying a possible discrepancy."
......
Mr Singh said it was also "of particular note" that the plane's emergency locator transmitter (ELT) did not send any signal after the crash.
"Was the ELT damaged, unarmed, mis-wired, or malfunctioning?" he said.

That reads a bit like Sky scraping the barrel and Mr Singh looking for his 15 minutes of fame.

The report describes that timestamp for the engine failure as "about 08:08:42" (given that it takes about 5 seconds for a GEnx to spool down after the fuel is cut).

Re the ELT not being triggered, it's located in a relatively undamaged part of the 787 (upper fuselage crown in the tail) and it's possible that the g forces sustained by that part of the structure in the crash didn't reach the 5g or so necessary to activate it.

 

[Regular.Cyclist]

The timings on the report are interesting. Both full cutoff switches were set to shutdown, 1 second apart, 3 seconds (and 4 seconds) after liftoff and were transitioned back to run at 10 and 14 seconds after.

The first officer was pilot flying and the captain, pilot monitoring.

It has been commented on a lot that the landing gear was never raised. I imagine things would have become quite busy in the cockpit three seconds after takeoff when the aircraft would have begun to lose thrust.

 

[DaveReading]

It has been commented on a lot that the landing gear was never raised. I imagine things would have become quite busy in the cockpit three seconds after takeoff when the aircraft would have begun to lose thrust.

Landing gear is only raised once a positive rate of climb has been established, for obvious reasons. Though clearly the aircraft did become airborne, it struggled to climb much above the airport level.

Once the engines had shut down, the RAT would provide sufficient hydraulic power for the flying controls, but not enough to raise the gear.

The irony is that, had enough power been available to raise the gear, it seems likely that the reduced drag would have provided enough breathing space for the engines (or at least one) to spool up and fly the aircraft out of trouble.

 

[presta]

I think pilots are given some credit for common sense. The switches are used at the end of the flight to shut down the engines, and it's assumed that they will very rarely be used at any other time.

It would be a bit like having a warning placard on the control column saying "Don't keep this pushed fully forward for any length of time or you'll hit the ground". Pilots are assumed to know when to do and when not to do things.

I recall an episode of Horizon years ago which was about the way aircraft cockpits were so full of warning lights and bleepers that they'd become like the boy who cried wolf.

 

[lazybloke]

I recall an episode of Horizon years ago which was about the way aircraft cockpits were so full of warning lights and bleepers that they'd become like the boy who cried wolf.

From the tiny amount of voice recorder transcript i saw, one interpretation is apparent pilot confusion about fuel being cut off. My immediate thought was a bloody great klaxxon to eliminate any such doubt.

Maybe such a warning DOES exist? Although if i remember correctly, the fault warning for MCAS was an $80k option. Whoops.

 

[DaveReading]

There are plenty of aural alarms on a modern jet airliner. I don't think the confusion resulted from lack of one.

 

[Mike_P]

I

There are plenty of aural alarms on a modern jet airliner. I don't think the confusion resulted from lack of one.

Problem identified in many crashes is too many alarms/warnings occurring at the same time.

 

[lazybloke]

There are plenty of aural alarms on a modern jet airliner. I don't think the confusion resulted from lack of one.

And yet the "MCAS crashes" had missing alarms or indicators, and google reports the seriousness of the underlying sensor problem had been known in advance by the manufacturer.

I wasn't trying to start a serious discussion, as none of us have enough facts. My only point was there should never be any doubt about whether or not the fuel has been cut off or not.

 

[DaveReading]

My only point was there should never be any doubt about whether or not the fuel has been cut off or not.

The doubt appears to have been about how and why, not whether. Both engines spooling down is hard to miss.

 

[presta]

Problem identified in many crashes is too many alarms/warnings occurring at the same time.

That's precisely the point that was being addressed in the Horizon programme I was referring to. The argument was that there were so many that there was a risk not only of them going unnoticed, but ignored like the boy who cried wolf.