Flyingnewbie
What was: The plane had a given deceleration
What we don't know whether it was or not as yet: The runway was (very) slippery
I don't know how you read the FDR graphs but to me, if an aircraft only achieves a deceleration of 1.2m/s/s with
full brake pedal pressure, that braking indeed qualifies as very *poor* and the runway as *slippery*.
It deals with a "Minimum Hydroplanning Speed" i.e., a threshold above which you should not apply braking when facing a slippery runway.
No, it does not say that at all.
Min hydroplaning speed is the speed above which your tyres might face dynamic hydroplaning, whether they are turning or not.
Now the technique, and its explanation :
..."
The anti-skid system will not operate until the main wheels of the aircraft spin... don't lock your brakes before touchdown"...
For a better illustration of the phenomenon and recommended piloting techniques , see the links I provided in some of my latest posts : #2165 "BAC wet runway guide", which deal with physics, really, and #2177 "Landing on slippery runways".
Worth a read, really !
Lemurian