What's that noise?
Thread Starter
Joined: Oct 2009
Posts: 543
Likes: 15
From: North West UK
What's that noise?
On the many flights I have taken on Airbus planes (usually A320s or similar) there is a moderately high pitched 'winding' noise that comes on as we start to move away from the gate and after we park up.
It sounds a bit like an electric screwdriver but more painful.
Any ideas?
It sounds a bit like an electric screwdriver but more painful.
Any ideas?
Paxing All Over The World
Joined: May 2001
Posts: 10,842
Likes: 328
From: Hertfordshire, UK.
Probably the Power Transfer Unit.
http://www.pprune.org/passengers-slf...ound-a320.html
http://www.pprune.org/passengers-slf...ound-a320.html
Mmmmm PPruuune!
Joined: Jul 1998
Posts: 600
Likes: 5
From: UK
AB has 3 Hydraulic systems Blue Green and Yellow. Blue and yellow are connected by way of a power transfer unit (PTU) this allows the one hyd system to drive a pump pressurising the other & visa versa, they are normally powered by engine driven pumps. On pushback starting No2 (right engine) will pressurise the yellow system which will start a ptu test and power the blue system. It the PTU running which sounds like dogs barking or a sawing sound. The reverse happens on taxi in if the right engine is shut down unless the yellow electric pump is turned on.
Hope that helps but it is quite normal
Hope that helps but it is quite normal
