Posts by user "digits_" [Posts: 5 Total up-votes: 0 Pages: 1]

digits_
June 12, 2025, 17:29:00 GMT
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Post: 11899514
What does a RAT deployment sound like inside the cabin? Could the mere deployment be perceived as the 'loud bang' in a high stress situation?

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): RAT (All)  RAT (Deployment)

digits_
July 11, 2025, 21:02:00 GMT
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Post: 11919794
It would be nice to see a graph of g forces/turbulence. An awkward arm or hand position in combination with sudden turbulence and perhaps worn out switches could hit both of them.

Sleeves or lanyards that got caught while moving around? Perhaps there was an attempt to press a radio button, although it would be a strange time to do that. But perhaps an 'oh crap, I forgot to get that frequency ready' moment.

Subjects: None

digits_
July 11, 2025, 21:05:00 GMT
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Post: 11919798
Originally Posted by The Brigadier
That \x93I didn\x92t\x94 on the CVR doesn\x92t sit right. If the cutoff switch movement was accidental, one would expect shock, confusion, or immediate troubleshooting, not a flat denial.
Not really. It might also indicate that he saw them move, knew his hands were somewhere else, or a plethora of other reasons. Even if one accidentally moves a lever or pushes the wrong button, the first response would likely be denial as well, then followed by an 'oh oops, turns out I did'.

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CVR  Fuel (All)  Fuel Cutoff Switches

digits_
July 11, 2025, 21:16:00 GMT
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Post: 11919815
Originally Posted by DTA
The switch state could be either on or off in that position. However, the CVR makes it pretty clear that the switches were moved deliberately to off. Just not why. Also, remember the report says one switch was moved then the other. Not together.
The exact quote was

"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."

Does anyone know what the sampling frequency of the data is? If we get one readout per second, then it's possible that a one second difference could only be a millisecond difference in real life, which doesn't necessarily rule out an accidental bump.
If there truly was a second of difference, there aren't many other options than an intentional act. Not necessarily with the purpose of crashing the plane though (confusion, hallucination, distraction, ..)

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CVR  Fuel (All)  Fuel Cutoff  Fuel Cutoff Switches  Preliminary Report  RUN/CUTOFF  Timeline (Preliminary Report)

digits_
July 11, 2025, 21:48:00 GMT
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Post: 11919851
Originally Posted by GroundedSpanner
With a one second gap between them?
Again, you can not conclude that from the report.

Different inputs are sampled at different rates. Some very basic info here: https://scaledanalytics.com/2023/04/...uses-767-data/

It's highly likely switch positions are only sampled at 1Hz, and not at 100 Hz. For engine parameters you'll likely want a higher sample rate, as the whole engine could go from perfectly fine to exploded in less than a second.

If you had something like:

08:08:42.96 UTC: cut off switch 1
08:08:43.01 UTC: cut off switch 2

It would likely be recorded as:

08:08:42 UTC: cut off switch 1
08:08:43 UTC: cut off switch 2

Leading you to believe there was one second between these 2 actions, whereas it was actually only 50ms.







Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All)  Fuel Cutoff Switches  Parameters  Preliminary Report  Timeline (Preliminary Report)