Airbus noise question
 

A bit of an anorak question from a curious passenger, but:

On an A320 recently, we were, I'd say, a good 20ish miles out from the airport and descending, when a noise suddenly started as if something had disturbed the airflow, accompanied by (very mild) buffeting.

My wife, who is a very nervous flier, asked me what the noise was, and I automatically replied "spoilers", but when I looked out at the wing, everything appeared clean (spoilers down, flaps/slats up). This noise continued until it was eventually drowned out by the sound of flaps, gear etc.

Could a pilot out there suggest what the noise might have been?

What part of the wing were you able to see? The initial flaps setting only includes the slats on the leading edge. So maybe that was causing the noise and you were just unable to see them from your place...

If the crew was flying fast, you might have noticed the landing lights? Esp. at speeds over 300 they cause a light rumble in the airplane.

They hang on the inboard side of the wings aligned with the airfoil, and are extended into the airflow if selected from the cockpit, usually about 15 minutes before landing.

[ 20 February 2002: Message edited by: Pegasus77 ]</p>

I will bet my shirt it was the aircon ducts. very,very common phenomenon when the bleed valves are playing up a bit. <img src="tongue.gif" border="0">

Landing lights for sure, like Pegasus said. the most daft piece of design qwork on the Minibus <img src="rolleyes.gif" border="0">

Thanks guys. Landing lights make perfect sense. Now I can go back to appearing knowledgeable to the wife again <img src="smile.gif" border="0">

It might have been that awful "Buzzsaw" noise that the A320 is well known for having but I doubt you could here it sitting back behind the wing. <img src="tongue.gif" border="0">

747FOCAL

That buzzsaw sound! You should try it from the ground 3 miles out on departures. The little 319s are noisier than the full loaded 777s that just rumble past.

Strange that!

Speaking of noises from the 320, I have another one (I am not a pilot, so please bear with me). I was on an AF 320 the other day, and all during the taxiing (to the runway, and after landing), there was a loud noise coming from the plane that sounds as if something is trying to engage, but it fails. It was as if the plane had hiccups. The sound did not stop at all until the plane took off (or when engines where shut down when it arrived at the gate). It was annoying as hell. Any idea what that might be?

Many thanks.