What deceleration rates do Autobrake "low" and "medium" give on an A320 just out of interest (assuming dry runway; typical landing weight) and what sort of ground run distances do these translate to?
You select Max at take-off (if rejected) and it becomes active when ground spoilers are deployed. You use low and medium for landing:
LO waits 4 seconds (!!!) after ground spoilers are deployed and gives 1,7 m/s/s deceleration (5,6 feet/s/s)
MED waits 2 seconds only and gives 3 m/s/s (or 9,8 feet/s/s)
If the antiskid is active (slippery surface) you will not get those deceleration rates.
From experience and without saying it is what should be done, if I felt that even although the computed landing distance for very wet runway was available, the braking might be a serious concern, I would not use the autobrake, but slam both brake pedals "to the floor" as soon as on the ground and let the antiskid do its best with that.You can even brake as hard as you can before touching the ground.You will not block the wheels.