Funny Airbus noises

[print744]

deadheading on an A320
funny“rih ruh “ noise coming from wing area while taxiing out.
Just curious what it might be. Aircraft already trimmed, tof flaps already set, but for several minutes there’s that noise... “rih ruh... rih ruh.., rih ruh...”
ive heard it a bunch times before, always wondered though.
Any ideas?

[Feather44]

The PTU (Power Transfer Unit) maybe?
A pump that pressurize hydraulic systems.

But its located in the main wheel well.

[eckhard]

Yes, it’s the PTU. Normally heard in the central cabin area (over the wing) after engine shutdown but will also run during second engine start on a single-engine taxi-out.

Some reckon it sounds like a dog barking; others say they think someone is trying to saw the wing off........

[eckhard]

We crossed!

[Capt Fathom]

Funny Airbus noises

Well at least it gave you a laugh !

[Chris Martyr]

Yes they like making funny noises them Airbus's do .
You've also got the 'ghostie noise' ,,,,APU running but no packs .
And the , "is there a combine harvester working around here somewhere" noise. [Brake Fans]
But the hydraulic transfer one is the one that gets most attention. I believe the MD-11 does similar .

[eckhard]

What about the “milk-bottle” howl from the fuel bladder inspection holes? Solved by attaching a small fairing.

[Dufo]

I remember flying out of Dublin on an A320. When boading, we saw several dogs in cages being loaded into cargo holds, then during start there was this famous PTU barking noise. One guy said 'poor dogs' and some ladies got really upset and called the cabin crew.