A320 QRH - Dry ALD > Wet in ELEC EMER CONFIG
Having studied and worked in Performance Engineering in an earlier life I'm embarassed to ask this here but so far I've had no luck explaining the following Actual Landing Distance (ALD) anomaly:
Between the older and newer models we have 5 different groups of A319s, A320s and A321s.
With regard to the ELEC EMER CONFIG checklist from Abus
4 fleets shows the ALD (DRY) < ALD (WET).
1 fleet (older 319s) ALD (DRY) > ALD (WET).
(That would mean in a true emergency we should call CFR to hose down the runway?)
Airbus say the numbers are correct. The failure factors for that fleet group, particularly the dry factor, as defined by the various regulatory bodies, are significantly higher than for the other groups and when applied to normal performance data result in the anomaly described above.
Am I missing something here?