Originally Posted by infrequentflyer789
Only two pure hydraulic, but also two hydraulic-electrical systems behind them for backup. The latter systems are new on the 380 I think - with previous airbus models having 3 hydraulic.
I've also seen these systems referred to as "hydro-electrical" - which could get awfully confusing to an EE...
The A380/787 are moving towards what I have been taught as more electric aircraft.
That is removing all the 'typical' engine driven hydraulic pumps and coloured systems (Blue, Green & Yellow for Concorde) with local electric motors powering local hydraulic pumps for flaps, slats, flying controls etc.
The use of electric motors powering flaps and slats was rejected due to the much higher probability of a mechanical system jamming vs a hydraulic one.
Apparently this 'contained' system of individual electrical motors and pumps gives weight savings and increased redundancy.
Unfortunately I cannot remember anymore details on all the MEA stuff I learn't!