A320 FMS inputs

[Rarife]

Great. To make it more complicated. Captain called and he said they have 700 kg trapped fuel in center tank and that it is included in total 6300 kg block fuel. It is supposed to be something what we call final fuel and it should be real value that is in the aircraft. I do not where they get this value but I always expected this to be FOB from ECAM. I think that means they really want to have or already have that 6300 kg of fuel on board. This is the value I would put into FMS as expected fuel but maybe they do that earlier. However we use two load sheets for each flight. First is preliminary, sent 30 minutes before STD after recieving final fuel from crew. Second, is final, very short one and this can be sent just before take off. It is just confirmation that there is no or very small difference from the preliminary version.

So it ended up like
Preliminary LS
ZFW was 700 higher than real one
TOF was 700 kg lower (5400 kg take off fuel. Instead of 6100 which would be 6300-200 for taxi)
TOW was ok

Final LS was same.
I understand that crew can not know ZFW. it is our job and they put what they recieve to FMS. But as I pilot I would not like why my take off fuel does not match what I wanted. And after start up my fuel would be ok (I mean ok with what I wanted, not the load sheet) but my TOW would suddenly jump up.Than I recieve the final LS and my TOW on LS is lower by that 700 kg.
We can make non-standard fuel loading. It is ok but there is another box called trapped fuel which moves the amount of fuel from block fuel to ZFW. And it causes all this mess. As I said. For B777 we have to send them that they are supposed to use another ZFW for FMS. Not the one from load sheet but the one from aditional information on LS where we manualy put ZFW lowered by that trapped fuel. Not really lowered but in fact the correct one.

For calculation take off performance, do they use the expected fuel mass they put intially or the real fuel? But I guess it depends on airline when they do that. I think that they use the real values because I guess they can not do performance calculations without load sheet and we send load sheet after we get final fuel from them.