This guy posted a better quality video than most uploaded and makes a strong case that the RAT was deployed.
Assuming the original files are as recorded, that sound is extraordinary. And it includes another relevant sound, or perhaps lack of sound…we should be hearing a pair of engines at full power. If the RAT is extended, then the entire tone of this event changes, and people will start looking at Boeing again.
As we know though, the RAT only extends for a couple of reasons, one of which is dual engine failure. The likelihood of that is vanishly small, so many commentators are dismissing it and moving towards more likely causes. As Captain Steve says, birds are unlikely, because we don’t see any smoke or flashes of flame, and anyway, they’re huge engines and would be reasonably resilient. Any shutdown would also tend to destabilise the aircraft in yaw, and we don’t see that, or any rudder input.
Fuel contamination. Not likely either. There would have been many other aircraft affected, and it wouldn’t strike both engines at the same instant. Fuel actually comes directly from individual collector tanks, so even though the aircraft was refuelled, most likely, most, if not all, of the fuel in those tanks was from the previous, successful flight.
Flaps. Images in the air definitely show the slats to be extended, and I’m pretty certain that you can make out the break line at the trailing edge. Shots of the wreckage would seem to confirm that. Wrong flap? We’ll come back to that.
So, people come back to what is possibly the most popular explanation. What if the non flying pilot select flap up instead of gear up. The wreckage images seem show flaps at least partially extended, but I suppose they could have been retracted and then reextended. Well, then the event as described in Captain Steve’s YT would play out.
In large part, the idea of a support pilot mistake is based upon the landing gear remaining down. It’s worth noting that the landing gear on the Concorde that crashed in Paris was also down, even though it was selected up. The gear won’t retract if there’s no hydraulics, and probably won’t with a range of electrical issues.
Take off configuration error. This is checked electronically (though from what I hear, not quite as robustly as Airbus), but it is still checked multiple times. The aircraft would not have rotated normally, and most likely would have suffered a tailstike. The rotation numbers (Vspeeds) would have been wrong.
People like the pilot error side because it has lots of form, and seems to fit the video images, although I think it fails given that slats are clearly visible in flight, and the wreckage seems to show extended flap. If the aircraft took off at flap 5, and the flaps were accidentally taken to flap 1, the wreckage would probably look much the same, but going from the 767 numbers, I think it would have flown. I’m sure that’s currently being run in many sims around the world. Historically, when I’ve made (or seen others) a switching error, the immediate reaction is to reverse whatever you’d just done.
But, right now, for me, the sound and its lack is the most compelling item. The apparent lack of the engines at full charge, combined with the unusual whine as made by a RAT. If what that implies is true, then everything else follows on. The gear won’t come up, and the aircraft won’t fly for long.
So, let’s just add a question. If we assume that it isn’t pilot error, then what could possibly cause a SIMULTANEOUS shutdown of both engines? Pretty well every failure that I can think of would have some level of lag between the shutdowns, which means I’d expect to see some sort of yaw/rudder activity, even if only momentary.