'It is interesting to note that in 2003 JAR-25.109(d) (Now CS-25) (well after JAR-OPS) was amended to include "Wet Grooved performance", which can be calculated on the basis that braking action on Wet grooved runway is seven times better than wet braking action on a smooth wet runway (Dry braking action is ten times better than that on a smooth wet runway).'
Oldflyer,
That's excellent stuff. I wonder if EU-Ops has left that bit unchanged? This reinforces my point that there is practically a big difference in braking action between stopping distance on a wet (i.e. covered in up to 3mm water) runway and on a well drained 'so called wet' grooved runway.
A duty officer, who checks a grooved runway can be reassured of this fact when he/she declares the runway technically 'damp', instead of erring on the side of caution and declaring it 'wet'.
I haven't noticed that I use any more RW at LCY on wet days compared with dry.
FODCOM 3/09 has given UK Operators just another deviation from EU-OPS to contend with.
