A320 A/Thrust Failure
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A320 A/Thrust Failure
A/Thrust fails in flight with AP1 engaged so to recover autothrust you can engage AP2 so that it runs on the FMGC 2 channel. With the APP p/b pressed on the FCU for an ILS approach, you go to press AP1 again. After looking through the FCOMS and other notes I reckon you will only get CAT3 single as AP1 will not engage.
My reasoning behind this is that AP1 is the master when you have AP2 engaged also (CAT 3 Dual) and therefore runs off FMGC 1 however the Autothrust cannot run off FMGC 1 due to the earlier failure of the A/Thrust. I have gathered an understanding of what is going on here but cannot find a definitive answer after sifting through the books.
My reasoning behind this is that AP1 is the master when you have AP2 engaged also (CAT 3 Dual) and therefore runs off FMGC 1 however the Autothrust cannot run off FMGC 1 due to the earlier failure of the A/Thrust. I have gathered an understanding of what is going on here but cannot find a definitive answer after sifting through the books.
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Hi Easy226,
You have 2 options:
1) Leave only AP2 engaged and do CAT3 Single.
2) Engage both APs - but Autothrust will fail because FMGC1 is the master - thus CAT2 only.
Edit Σεβασμός aristoclis.
You have 2 options:
1) Leave only AP2 engaged and do CAT3 Single.
2) Engage both APs - but Autothrust will fail because FMGC1 is the master - thus CAT2 only.
Edit Σεβασμός aristoclis.
Last edited by rudderrudderrat; 16th Sep 2010 at 18:06.
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Hi there,
Option 1: You do not select AP1 after APP is armed. You have AP2 and A/Thr operating, you are CATIII single.
Option 2. You want for whatever reasons 2 APs. So you engage AP1 after APP is armed (I understand in your case A/thr Ch1 was the problem and not AP1). FMGC1 becomes master, A/thr fails again (if not transient failure). So you have 2APs but no Autothrust. You are CATII.
Regards.
Edit: Respect Rudderrudderrat
Option 1: You do not select AP1 after APP is armed. You have AP2 and A/Thr operating, you are CATIII single.
Option 2. You want for whatever reasons 2 APs. So you engage AP1 after APP is armed (I understand in your case A/thr Ch1 was the problem and not AP1). FMGC1 becomes master, A/thr fails again (if not transient failure). So you have 2APs but no Autothrust. You are CATII.
Regards.
Edit: Respect Rudderrudderrat
