Testpanel:
Why, why, does the speed brake does NOT "stow" when thrust levers advance?
Originally Posted by
misd-agin
AFAIR Airbus' speed brakes don't retract either. Instead it gives you and ECAM alert.
Why don't they? No idea. We'd have to be back to the later 1970's or early 1980's to ask why it was designed and certified that way. Perhaps it was "one step too far" for the parties involved in transitioning to the modern glass cockpits? Now we accept glass cockpits but there were significant trainings issues training pilots coming off of 'round dial gauges' to 'glass' /FMC cockpits.
Airbus FBW speed brakes DO automatically retract : if the thrust levers are set above MCT. (TOGA gate is above MCT gate, obviously).
From A320 FCOM: (my bold)
Speedbrake extension is inhibited, if:- SEC1 and SEC3 both have faults, or
- An elevator (L or R) has a fault, or
- Angle-of-attack protection is active, or
- Flaps are in configuration 3 or FULL, or
- Thrust levers above MCT position, or
- Alpha Floor activation.
If an inhibition occurs when the speedbrakes are extended, they automatically retract and remain retracted until the inhibition condition disappears and the pilots reset the lever. (The speedbrakes can be extended again, 10 s or more after the lever is reset).
In my opinion Airbus significantly improved aircraft design in many areas, including removing the 'external' TOGA switches to avoid accidental operation and re-siting the speed brake and flap levers away from the thrust levers.