Electric Hydraulic Pumps

The electric hydraulic pumps are controlled by the HSMU, in both automatic and manual operation. Only 1 electric pump runs at a time - the others are load shed.

On each system, electric pump flow is about 18% of engine-driven pump flow. Electric pumps can be used to retract surfaces, but are not a replacement for engine-driven pumps.

Green system

Has an automatically or manually controlled electric pump. Automatic operation:

in the event of failure of one engine, when the landing gear lever is selected up (runs for 25s)

Manual operation:

for the retraction of green actuated surfaces in case of loss of both engine driven pumps

Blue system

A330 basic

Has a manually controlled electric pump. Manual operation:

can be used to pressurise the park brake

A330E

Has an automatically controlled electric pump. Automatic operation:

in the event of failure of engine 1, and PRIM1 and PRIM3 faults - this provides backup for rudder operation (see backup control module)

Yellow system

Has an automatically or manually controlled electric pump. Automatic operation:

in flight in the event of failure of engine 2 with the FLAPS lever not 0, if the green electric pump is not running - in this case, the pump will continue to run unless turned off manually
on the ground during cargo door operation

Manual operation:

if manually used, has to be switched off after flap retraction

Categories: Airbus A330 | Hydraulics