A320 ELEC EMER + Auto FLT

[Sylphe]

In ELEC EMER CONF,
why A/P, FD, A/THR can't use ???
And other system such as NWS , REV , eventhrough HYD still operate ?

[I-2021]

Hi,

You can't use them because they are inoperative. So they are because not electrically supplied as a result of the emergency electrical configuration (the word emergency should make it easier to understand;)). To go deeper in the subject, check in your FCOM 1 the bus equipment list for the various aircraft systems to understand what is powered by what.

Cheers.

[Microburst2002]

You can survive without autoflight, specially if you still have navigation still available.

You can't survive without hydraulics. You don't have NWS, by the way.

[ReverseFlight]

And there is no REV either under EMER ELEC CONFIG.

[Sylphe]

So sorry , it's because of short question.. !!!!

The point is, why the AP, FD, A/THR can't use while Main vital system still available??
ELAC1, SEC1, FAC1, MCDU, FCU1 -> Flight computer can operate normally.
G HYD, Y HYD, some of B HYD -> Still normal.
Navigation still operate.
Most system still operate in main function. -> Aircraft can fly normally... (only fly)


Why the AIRBUS have to downgrade or disable AP, FD, A/THR?
The AP, FD, A/THR can reduce work load dramatically !!!!!

[mcdhu]

The quote below from the FCTM (AO 24) gives you the philosophy:

"The electrical distribution has been designed to fly, navigate, communicate and ensure passengers comfort. The ELEC EMER CONFIG SYS REMAINING list is available in QRH. The significant remaining systems are:

Significant remaining systems in ELEC EMER CONFIG
FLY; PFD1, alternate law
NAVIGATE; ND1, FMGC1, RMP1, VOR1/ILS1, DME1
COMMUNICATE; VHF1, HF1, ATC1
On BAT, some additional loads are lost such as FAC1 and FMGC1"

So they have allocated the electrical demands above to the busbars which remain powered in the Emergency Electrical Config.

mcdhu

[Microburst2002]

We would have to look at which are the conditions required to have AP, FD and A/THR. Probably they are not met with the remaining equipments. Also, flight control law is alternate, which doesn't mean that AP or FD are lost, but means that there are shortcommings in the flight controls due to the loss of equipment.

[Sylphe]

To mcdhu ...
i already know about that.........
but it's not the answer of my question.....
Is A/P FD and A/THR consume the electric power too much ????

The point is.... why A/P FD and A/THR can not use ?????

[dovish]

Sylphe,

I believe it is not a lack of electrically power related but rather a loss of other systems that will not allow the aircraft to use A/P and A/THR. Just like Microburst2002 said.

If both RA fail you dont have AP either and you are not in ELEC EMERG CONF ...