A320: Loss of G+B System
 

Hello fellows,

quick one: on the G+B loss Ecam says: do not use Speedbrake. I know why, but do they really deploy when you pull it or do we get a caution and nothing happens?

Thanks

SW

With G+B fail speed brake 2&4 is available and deploy if used. That's why.

No, speedbrake is inhibited, if the lever is moved nothing happens...

Hope I could help

Simon

Hi Simon, sorry you’re not correct.
From FCOM DISC-27-10-20 “Speedbrake extension is inhibited, if one of the following occurs:
- SEC1and SEC3 both are faulty, or
- An elevator (L or R) is faulty, or
- Angle-of-attack protection is faulty, or
- Flaps are in configuration FULL, or
- Thrust levers are above MCT position, or
- Alpha Floor is activated.”
Cheers.

When GB is lost you end in single elevator operation :)

yes I know. Tried it in the sim. There’s a speedbrake fault, it does not extend

Just out of curiosity: Next time you are in the sim, try the following (if they let you): G-B fail, as you already did and then switch off ELAC2. SEC becomes active on elevator and then try again deploying the Speedbrakes.

Cheers

And then it will extend? So airbus is covering the case that the sec takes over control?

G+B fail both ailerons are lost so spoilers 2&4 are only flight controls for bank. So may they are inhibited as speed brakes or don't deploy if you are banking.

Got that. But why do they write „do not use“ into the status?

I would then expect spoiler 2 to follow the order and spoiler 4 stays inhibited. That’s most likely why the ecam memo/fault whatever is generated…