Originally Posted by
seanthornton
Anyone know exactly what the pulsating and whining or groaning noises are when the Airbus powers up or down? Sounds like a dinosaur calling for its mother.....Just curious
It is the hydraulic
Power Transfer Unit, The PTU is used when there is right hydraulic system pressure but no left hydraulic system pressure. It transfers hydraulic power from the right hydraulic system to the left hydraulic system. There is no intermixing of hydraulic fluid between the left and right hydraulic systems during PTU operation. The PTU is able to operate the hydraulic motor generator during all phases of flight.
On start up it goes through a self test.
I thought it sounds more like a german shepard barking..
