A320 Loss of F/Ds
 

Hi,

I just wanted to ask you guys a question that my instructor asked me.
What are failures that causes the loss of F/Ds?
I can´t get the logic of F/D, do I need to check every abn procedure from the fcom?

thanks

Inboard and Outboard DU failure?:)


I'd imagine loss of the things it needs to monitor- ADC info, IR data etc

DSC 22_30-20 FD engagement, Disengagement and Automatic FD Removal.

Flight directors receive information from their respective FMGCs so a Dual FMGC failure results in the loss of both FD1 and FD2.
AUTO FLT FCU 1 + FCU 2 FAULT results in the loss of both FD1 and FD2.
In the Emergency Electrical Configuration, AP, ATHR and FD are lost.

Vilas: Yes I read that section but no information of the systems that effect fd removal

The question per se is totally meaningless. Have you tried asking him what is the benefit of knowing all the circumstances that will lead to the loss of FDs rather than knowing what is the impact of losing FDs in the various flight phases ?

I am totally agree with you but I am curious if people knows the answer or not
:8

The answer is whatever failure leads to the loss of FDs. They will disappear and you will get a red FD box on your PFD. Difficult to miss it.

Speed Protection.If you are flying without AP and don't follow FD then if the speed exceeds VFE or decrease below VLS the FDs are removed and ATHR changes to speed mode, the managed speed target becomes selected and ATHR maintains the speed.
But loss of FDs in abnormal conditions you will have to go through Abnormal procedures.

Have you thought that maybe HE is the one that doesn't know the answer? Maybe his question is just that, a question. It wouldn't be the first time I ask a question to the FO and he/she stares at me waiting for clarification.

We all get old and eventually start developing memory gaps. Next time he asks you, you ask him what he had for breakfast.

yeah I tought so.

Exactly. If it happens, it happens. What's more important is how you deal with it.

Perhaps the questioner wanted the OP to understand the generator fmgc logic and the fact that the apu gen cannot recover the landing capability.

Exactly.
Magenta over Blue; One Flight Director 2.
There's a totaled 320 sitting on the field in PHL that lies testament to the fact nursery rhymes can save the day....

Tell him you don’t care as you fly without them anyhow. 😜

I could be wrong, but I think they had the FD. Either way, that’s not why it’s there.

I do like the mnemonic though

No nursery rhyme was required for that accident.THRUST NOT SET message check the Thrust lever position if not set in Flex set it. If in Flex hit TOGA and continue or close thrust levers to idle, go back and find out.