When calculating the max T/O fuel you must consider the MAX
T/O mass and MAX LANDING mass.....ZFM is not relevant....zero fuel mass
T/O Mass = DOM + TL + T/O FUEL
LANDING Mass = DOM +TL + LANDING FUEL....(and LANDING FUEL = T/O FUEL - TRIP
FUEL)
So:
MAX T/O MASS = DOM + TL + MAX T/O FUEL
64400 = 35500 + 14500 + MAX T/O FUEL
Therefore MAX T/O fuel = 14400kg
MAX LANDING MASS = DOM + TL + MAX LANDING FUEL
56200 = 35500 + 14500 + MAX LANDING FUEL
Therefore MAX LANDING FUEL = 6200kg
BUT, if we land with 6200kg, we must T/O with (6200+TRIP FUEL), or 11100kg.
So we end up with 2 figures....14400kg (T/O) and 11100kg (Landing)....to stay
within both limits we must take the lower...