Hello Colin
Seems that you like Airbus aircraft, so here are some interesting facts related to speebrake use in the A320 family.
*(A320) With autopilot on, the maximum deflection will be achieved when you put the speedbrake lever at the "1/2" position. Even if the lever is at the "Full", the system won't allow you go further than half.
Although you have limited authority, it's just fine for most STAR's and ATC requests.
For full speedbrake deflection, you'll need to disconnect the autopilot.
*Speedbrake will retract automatically if one of the below conditions occur:
1- Flaps at FULL (3 and FULL for the A321)
2- Thrust levers above the MCT detent
3- Alpha Floor activation
4- Angle of Attack protection active (...and much more!)
This is extremely useful in a GPWS "Pull Up" call, for example. When you apply TOGA, the speedbrake will retract (although the memory item asks for you to check the speedbrake lever in the retracted position!)
Hope you enjoy it
