No it doesn’t have the geared turbo fan, just a GEnX design, just another iteration of the CF6-80/GE-90 line. The sound is just due to the acoustical design consideration and knowledge gained over the years. It’s a rather silent engine all in all!
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You post in jest but these things can be real issues… when RAAF replaced the F-111 with the F/A-18F the noise complaints around Amberley spiked through the roof. Not because the F-18 is actually any louder than the F-111 when going flat out, but because the F-18 uses a much higher power setting in the circuit than the F-111 does.
Actually, this might be the first time any group of people has seriously preferred the TF-30 over another engine 
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Some more information in this aviation herald post… Fuel cut to both engines. One was in-progress to recovery and the other was attempting to stop its own decelaration when recordings stopped.
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29 seconds, bless their souls. What is the likelihood that those switches both moved to cutoff without human intervention?
Zero chance.
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It was the same in the Global - Zero chance and I would hazard a guess that it would be the same for all FADEC aircraft. I am surprised that Run Switches are not guarded though.
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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.
Well that’s creepy.
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Question: Are the physical positions of the switches known, or are we looking at FDR/FADEC data indicating the switches were turned off?
Wiring/Electrical issue independent of the physical switches themselves?
Human fault is more likely, but worth a thought.
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I was thinking about the pilot asking the other one why he did the cutoff. Do you think that he would have asked that, without checking their physical condition? IMHO, with both engines off, the PF must have jumped on those fuel valves pretty quickly.
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Yup, after my post I read the report and it’s pretty clear. How awful…
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Since those switches doesn’t control the shutoff valves mechanically, but through an electrical circuit, that’s a valid question…
But, as @chipwich points out…
…one would guess that the position of those switches were checked.
The physical position of the switches may be hard to verify, post crash, but the investigators will be listening carefully for the sound of the switches, on the CVR.
That said, the question ”why did you turn them off” seems very strange as there is no reason for turning the fuel valve switches off, because the inevitable result is that the engines would die. So asking why it was done, seems a bit odd to me. OTOH, the stress level that comes from realizing what has happened may explain the dialogue.
It could also be a language translation error.
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Bbc is reporting that after shutdown, the switches were flipped back and automatic relit started. One engine was spooled and producing thrust and the other was lit but not thrusting yet.
Is that right @smokinhole? If you flipped those switches back to on, would the plane automatically relight?
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I read that the FDR shows the switches were flipped at 0.1sec interval… I guess that they are referring to the signals to the shutoff valves, as I doubt the physical position of the switches is recorded…?
Is it possible to flip both switches that fast, with one hand? Is it possible to flip both, simultaneously with one hand?
How many persons in the cockpit?
I assume the cockpit door is closed?
Ah! Strange way to write 1 second… But that may explain why it’s been reported as 0,1 sec in the media.
I have only read about two on the flight deck.
I assume so too.
Yes, the preliminary report lists a flight crew of 02 and a cabin crew of 10 people.
So we either have a suicidal crew member who shut off the switches, or some gremlin in the system spontaneously tripped the switches?
Are these switches guarded in any way, or have a pull-out before moving mechanism?
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Spring loaded pull and move. Both ways
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How close, physically are the two switches, If they are next to each other then a 1 second gap between activation is fairly believable