B777-200 descent

[Hokulea]

Hello all,

First post here and hope someone with a little knowledge will be kind enough to reply.

I'm a fairly regular long-haul passenger and am used to most of the noises heard on an airliner, but for the first time in ages I recently found myself sitting right over the middle of the wings on an American Boeing 777-200 on a flight from Chicago to London.

At around 15,000 ft descending into London I heard what I can only describe as a loud whining noise beneath me and I've not heard that noise before. It went on for a few minutes. We were too high and fast for flaps or landing gear and I also looked out of the window and the spoilers/speed brakes weren't deployed, so don't think it was any of those things. I'm just curious as to what it might have been. Sad question, I know, but I'd love to find out what it was.

Thanks.

[TightSlot]

Hokulea - we'll leave it here for now, and if there are no bites then maybe I'll move it to a more tech forum for an answer.

[perkin]

Could it be noise generated by flap extension? Perhaps not if flying at 15000ft, but just a thought. I've heard this on 146's and to a lesser extent 737's. By noise I mean a weird whiny sort of noise created by the change in airflow, as opposed to the sound of the actuators doing their job...Just a thought, happy to stand corrected :)

[slim_slag]

If all the stories are true they are probably on reserve fuel by that stage so all the pumps are turned on to find the last dregs of Jet A. lol.

[Habster]

Ralph Fiennes flying??

[apaddyinuk]

Hekoula, its possible that the noise you heard was infact one of the air conditioning packs. I have heard some rather odd noises through the years of working on the 777 that I have been concerned enough over to call in the chaps and chapettes from the front to come down and listen too! Always the same answer..."A/C PACKS"!!!

[Hokulea]

Hello again,

Thanks to all for replying to my original question. Perkin - definitely not flaps as we were high and still flying quickly, plus I did look outside and they weren't extended. The noise was very mechanical, I don't think it was airflow. Slim_slag mentioned fuel pumps, and I know the post was made in jest, but I did wonder if that's what it was although I'm quite confident we weren't running out of fuel ;). I think on several aircraft the fuel is balanced before landing so maybe that's what it was, but I really don't know. Apaddyinuk (great name!) - that sounds utterly feasible although I have no idea what one of those packs sound like, and as I said, I've not heard the noise before. Then again, sounds can be different depending where you're sitting so that might explain it.

TightSlot, thanks for the offer. If you think it's worth it I don't mind the thread being moved, but it really is just a question from a curious passenger. If I'd been a bit more awake when we left the aircraft I might have thought of asking the crew. Oh well, too late now.