The problem with using Wet runway data on a Dry runway is that it's illegal.
The normal rules require that a 35 ft screen height be obtained within the TODA, and that one means of retardation (inevitably reverse thrust) be kept in reserve. That's the rules.
Then, along comes a
DISPENSATION for Wet runways (Wet, not Dry or Damp) which allows the use of Reverse Thrust, and allows for a reduced screen height to 15 ft. The dispensation is allowed to be used,
ONLY IF THE RUNWAY IS WET!
The dispensation entirely removes the ONLY spare performance capability remaining on a Dry runway for a RTO, and significantly reduces obstacle clearance for the continued Takeoff.
There's absolutely nothing wrong with using the more limiting of the Wet and Dry RTOW for any runway condition (except Contaminated), provided that the chosen Thrust and V-Speeds used with the actual weight are for the actual prevailing conditions, i.e. Dry (including Damp) or Wet.
Regards,
Old Smokey
Old Smokey
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Some Facts given by someone much more knowledgeable in this area than I---
PA