As far as I know and checked in 320s . . the APU (HONEYWELL 131-9A) they do not supply any HYD system in any way.
HYD system is powered by Green EDP, Yellow EDP and ELEC pump, Blue ELEC pum and RAT, and NO APU BLEED is supplied to any.
Add to this both Engines failed, do you generally start APU for ELEC power ?
simply my question is based on these two, why APU is not used to supply ELEC power or HYD during engines failures ?
@Admiral346 : as far as I checked no APU BLEED is connected to HYDs in A320.
Also add more hey into the my fire of confusion! in case of an in flight engine shutdown, if the CSD is disconnected, No ELEC could ever get even if the engine is restarted. so we get another abnormal event. So my point is in a acse like that y can't we use the APU to supply ELEC? Am i making sense?
@Pontius : yes, all engines failure will bring in the RAT . . that is exactly my point, why can't the APU does what a RAT does? provided fuel, why can't it provide ELEC (or BLEED) to control the airplane more efficiently?
Thanks for replies! i cant dream peacefully!
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