Hi
Rarife,
Yea, I think it is mess.
It certainly is. Please see MEL - 28: Fuel CTR TK Pump 1(2) LO
PR procedure.
"FLIGHT PREPARATION/LIMITATIONSThe fuel in the center tank should be considered as not usable for the flight and counted as part of the ZFW.
Operational Flight Plan (OFP), Fuel Planning:
The minimum block fuel (TOTAL on the OFP) must be increased by the unusable fuel in the center tank.
This gives the new minimum block fuel to operate with Both Center Tank Pumps inoperative.
Weight and Balance:
Enter the total fuel in the LOADSHEET application (LOADING <F4>

. If there is unusable fuel in the center tank, use the FUEL DISTR <Alt F2> tab and select MANUAL DISTR. Enter the fuel as shown on the ECAM FUEL page.
As the LOADSHEET application cannot include some fuel in the Zero Fuel Weight (ZFW), proceed as follows: Check manually that the Actual Zero Fuel Weight (AZFW) is equal to or lower than the Maximum Structural Zero Fuel Weight minus the unusable fuel (AZFW ≤ MZFW – unusable fuel).
If there is unusable fuel in the center tank, the landing weight CG (LWCG) shown in the RESULTS panel (or MORE<F10>

must be within the following limits:
- Center tank unusable fuel less than 3 300 kg: LWCG within the MLW envelope reduced by 2 % in the forward and aft limit.
- Center tank unusable fuel between 6 600 kg and 3 301 kg: LWCG within the MLW envelope reduced by 4% in the forward and aft limit."
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