Hi again, TO MEMO,
Thanks, I see that the decrement for "fluid contaminated" runway case is much greater (by about 2T) if the dry RTOW allows for the clearway, just as you said.
Does your dry RTOW of 69.1T allow for the clearway or not, and what flap is it based on? I do not fly A320s any more, so I don't have access to any A320 performance manuals, even if I knew which A320 you are flying.
So I am going to need 2 dry RTOWs to complete my explanation, and they must both be based on the flap you intend to use in the "fluid contaminated" case:
(1) Dry RTOW for TORA=1800m and TODA=1800m (i.e., no clearway);
(2) Dry RTOW for TORA=1800m and TODA=1980m (clearway=180m).
I realise that if you are using airport-specific tables you may not be able to give me a figure for (1). But if you can, I suspect that the dry RTOW (2) may be in the order of a couple of tonnes greater than (1). By the way, if you are not sure whether to use Flaps 2 or Flaps 3, let's look at the dry figures for both.
Chris