Posts by user "Musician" [Posts: 83 Total up-votes: 0 Pages: 5]

Musician
July 18, 2025, 04:57:00 GMT
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Post: 11924842
Originally Posted by galaxy flyer
I would guess the OP on this subject is wildly overestimating “survivability”. Any chance off-airport barely controlled impact is gonna be catastrophic. There maybe survivors but that’s just luck.
To clarify, I did not mean to imply that a "miracle" was possible. There was always going to be a high chance (inevitability?) that the fuel would explode, especially with the engines relit.
We're speaking here on the amount of luck available. As it turned out, even crashing into buildings, it sufficed for one passenger to survive. So there's more luck here than with a CFIT from cruise—and some bad luck in not missing the house they crashed into.

Last edited by Musician; 18th July 2025 at 05:46 .

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Musician
July 18, 2025, 05:18:00 GMT
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Post: 11924846
Thank you for your reply, appruser , and apologies fur cutting most of it:
Originally Posted by appruser
Big questions in my mind:
1. If the loss of ADSB corresponds to the E1/E2Fuel Cutoff switches being moved from RUN -> CUTOFF, why is the airspeed declining for the prior 4 seconds?
2. In 4 seconds, why is there only 50ft of altitude gain? that seems odd.
3. To account for only 50ft of alt gain, if we assume the 1st reading is on the runway just before rotation, the intermediate +25ft alt gain is at rotation (Nose up but MLG still on the runway), and the last 4 readings are in the air (nose up an additional 25ft), that means that 1 second or less after lift-off, ADSB was lost - this is before E1/E2 FCO RUN-> CUTOFF.

It's just weird .
1. I don't know that the transponder lost power, because I don't have knowledge which electrical bus it is powered from on the 787. It may well have been powered from the main battery the whole time. The FR24 receiver may have stopped receiving data because it could no longer "see" the aircraft‐‐we know there are issues because it didn't even see the eastern half of the runway.
2. Altitudes are rounded, so this could be close to 75 feet gain‐‐or a gain and decline, if the data covers the top of the trajectory.
3. The first reading is definitely in the air, after rotation. FR24 does not report the altitude when the ADS-B data indicates that the aircraft is on the ground, and their data download confirms that.

The best bet to establish timing is to use rotation as datum, and then match the altitude/time estimates from the CCTV with position/time from the ADS-B and the estimated ground speed of the aircraft.

The fact that the ground speed is declining throughout the data sequence strongly suggests that it begins some time after the point, or at the point, when thrust was lost. And we know that didn't begin to happen until the aircraft was 3 seconds into the air.

Last edited by Musician; 18th July 2025 at 05:38 .

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): ADSB  CCTV  FlightRadar24  Fuel (All)  Fuel Cutoff Switches  RUN/CUTOFF

Musician
July 18, 2025, 05:36:00 GMT
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Post: 11924853
Originally Posted by andihce
[...snip...]
We are not conducting either a criminal trial, or a civil trial here. I would rather call it (perhaps optimistically) a "scientific enquiry". I think the standard to be applied is whatever we (individually or collectively) think is reasonable, is order to fairly reach a meaningful conclusion. The standard for a criminal trial need not apply.
[...snip...]
Inasmuch as a scientific enquiry is based partially on rumors and conducted before all the evidence is in, yes.

The disconnect in the discussion stems partially from some speaking to what is " reasonable " while others talk about what is possible , given that we don't have all of the evidence yet.

For example:
Is it reasonable to assume the switch was defective? No .
Is it possible that it was? Yes .
Could future evidence change what is reasonable? Yes, but it probably won't. Wait and see.

So all of this can be true simultaneously, and if you don't pay attention to the context, that "yes" and "no" clash. (Can we call that a hamster fight? )

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