QANTAS A330 Air Con Noise?

[blueloo]

Having flown in QFs A330's a few times now, and on their newest A330-300 the other day, can anyone explain why there is a really annoying and a little concerning noise from the overhead middle (lengthwise) aircondition ducts in the cabin - I have heard it on a few of the planes now - it sounds like little jagged pebbles being blown through the air con system - it occurs just after engine start up (presumably when packs are switched back on) and regularly during cruise - most pax look up at the ceiling with concern...

Is it leftover debris/offcuts from manufacture or something shredding itself in the system?

[The The]

It's ice crystals.

[Rabbit]

The The is correct. The Air Con' system is too efficient in order to cater for weather in any part of the world, so in certain conditions you will hear the tinkle tinkel of ice particles mainly on the left side middle where the riser tube joins the horizontal above the windows.

Have a nice day

[Beer Can Dreaming]

Dunno what the hell the noises are but it was mentioned in another thread about Airbus vs Boeing.

Find the A340 in particular very noisy on long haul flights and the temp vary wildly throughout the cabin.
On a flight to Santiago recently it sounded like the hound of the baskervilles!
A few years ago on a flight to Cairo with Air Egypt they couldnt cool down First/Business Class and we had to swelter.
No reasons supplied.

To make matters worse have you heard the hydraulic noises mid cabin in those babies???
Sounded like grinding metal or someone trying to kill the Baskerville pooch!
No wonder they went through phases of hydraulic pumps catching fire and burning the aircraft into two pieces on the ground whilst under tow.
Really instills confidence.

As for the other manufacturers they aint saints either with Capton wiring fires and fuel pump hassles etc.

Havent yet had the honour of riding the A330 but I can tell you I quiver with anticipation..............
Beats a Tupolev/Illyushin or Yak anyday though.

[AN LAME]

Sorry, I can't resist what is probably obvious to most... the sound from the main wheel well is the hydraulic Power Transfer Unit, not an hydraulic pump which makes that jerking whining noise. I think it was a Yellow hydraulic pump which caught fire after it was left running for a couple of hours due to a mis-positioned cargo door switch.

"You can teach a monkey to ride a bike...":ok:

[ZK-NSJ]

an old air con installers trick if they have been pissed off by someone in management, they go to novelty shop and buy a whole lot of 25cent whistles, they then proceed to pot-rivet the whistles throughout the ductwork.........