A320 Hyd G + Y SYS LO PR

[dream747]

Hi all,

Just a quick question, I noticed that on the A320 if you lose both green and yellow hydraulic systems, the procedure does not call for the selection of the yellow electrical driven pump. I can't find any explanations as to why we can't use the yellow electrical pump if we have electrical supply?

What happens if I turn on the yellow electrical pump? Is the pressure sufficient and will the PTU power the green hydraulic system? And we can possibly have some flaps?

Thanks for any suggestions. Still learning very much on the A320.

[Checkboard]

HYD G + Y SYS LO PR
...
-PTU OFF

-Affected PUMPS OFF


if yellow sys lost by ENG 2 PUMP LO PR
-YELLOW ELEC PUMP ON



:confused:

[macdo]

Just an added thought,
the Yellow Electric Pump is primarily used to raise and lower the hold doors when the EDP's are off.
As such, it is auxiliary to the main functions of the Yellow EDP systems and may Overheat if used for long periods.
This is alluded to, but not expanded on, in the HYD Y ELEC PUMP LO PR or OVHT ecam procedure.
In addition, I have had several instances where the Yellow Elec Pump has stuck on after the Loaders have opened the Hold Doors, unless noticed on the SD page, this invariably ends up with an ECAM Caution for pump ovht.
Lastly, the a330 has an additional electric pump which activates during Gear Up. This remains on during the EFATO procedure and also overheats unless manually switched off.
Better than nowt, but I wouldn't rely on it!

[Microburst2002]

One thing is a lost pump and quite another thing is a lost hydraulic system.

If a system is lost, it is lost, no matter how many pumps you have. Actually, you have to switch them all, including the PTU if any. isolating the system and thus preventing it from creating more problems, means that we lose the system.

If only the y eng pump is lost we can use the Y elec, if we were so unlucky that we lost the PTU, too. otherwise it is better to let the PTU do its job.

[dream747]

Thanks guys... cleared things up!

[Microburst2002]

iI said "switch them all" instead of "swith off them all"