usable fuel
usable fuel is the fuel available for flight planning. Unusable fuel is the quantity of fuel that can not be safely used in flight
en-US/ˈjuzəbəl ˈfjuəl/
en-GB/ˈjuːzəbəl ˈfjuːəl/
usable fuel is the fuel available for flight planning. Unusable fuel is the quantity of fuel that can not be safely used in flight