Airbus Lounge What is that noise?

[Soul Brotha']

When descending at around 2-3 thousand feet there is a whoosh/almost light flushing sound on the A320 family(not sure if the other types do it). I’ve asked numerous people including a check airmen and no one knows. It only happens on descent. What is that sound?

 

[BobDDuck]

When descending at around 2-3 thousand feet there is a whoosh/almost light flushing sound on the A320 family(not sure if the other types do it). I’ve asked numerous people including a check airmen and no one knows. It only happens on descent. What is that sound?

The engines rolling back to idle will cause a whooshing noise in the air system. But that's generally not happening at 3000 feet.

 

[SteveC]

I don't know squat about the Airbus, but on my old plane there would be a whoosh when thrust was reduced and the pack/pressurization system would switch from the low pressure bleed source to the high pressure side to keep up with demand.

 

[///AMG]

I've noticed something similar in the 737, sometimes more noticeable than other times.....just assumed it was the pressurization system doing its thing. Or the avionics fans, or something.

 

[turbojet28]

Could be the avionics ventilation system switching from closed to intermediate configuration? But that only happens if descending into a pretty warm area.

 

[Cory Trevor]

My guess is the spoilers. They’re definitely noisy on the bus. I live right by the DPA VOR where planes will generally be slowed to 210 and turned onto base into ORD and you can hear it from the ground too.

 

[Boots2Wings]

Maybe just increased airflow to the packs, caused by the engine idle changing to approach mode as Flaps 3 are selected? I think thats how that works *shrugs*.

 

[Autothrust Blue]

Could be the avionics ventilation system switching from closed to intermediate configuration? But that only happens if descending into a pretty warm area.

Everywhere is a warm area nowadays so this is probably it. Sounds like a toilet tank fill shutting during climb out, when it goes the opposite direction.

Maybe just increased airflow to the packs, caused by the engine idle changing to approach mode as Flaps 3 are selected? I think thats how that works *shrugs*.

IMS, approach idle is selected when the flap lever is moved to 1 or greater.

 

[Chief Captain]

I think it's got to do with the pressurization system. The sound stops and starts at a differential pressure of ~1.9 in the climb and descent.

 

[roundout]

Thank you for not asking about the barking dog, though.

 

[Soul Brotha']

Thank you for not asking about the barking dog, though.

It’s not a barking dog. Everyone knows that it’s a little person sawing something. Duh.

 

[///AMG]

It's the langoustines coming out of the cargo bay. Super French. You probably wouldn't understand. They're small lobsters, you uncultured American pilots

 

[Skåning]

Super French. You probably wouldn't understand.

Some ‘Buses are made in Alabama!

 

[Minuteman]

It's the langoustines

Langoliers?

View: https://www.youtube.com/watch?v=ZcmnG8ttLbU

 

[///AMG]

Langoliers?

View: https://www.youtube.com/watch?v=ZcmnG8ttLbU

haha such a 90's plot

 

[ERfly]

haha such a 90's plot

It was a great movie, until you find out the killer is Pac Man.

 

[vheissu]

I know the sound you're talking about. This is the best explanation I've been able to find.

 

[Soul Brotha']

I think this is what I was looking for.

 

[Itchy]

As long as it keeps making the noise I say. Otherwise that write up is gonna sound goofy.

 

[///AMG]

View attachment 74198

I know the sound you're talking about. This is the best explanation I've been able to find.

I think Sullenberger op checked this as go