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[Chris Scott]

Fuel Distribution

Lonewolf50,

As you still seem to be waiting for an answer to your fuel-tank management question, and with A330-drivers PJ2 and CONF_iture apparently AWOL, I'll try and shed some non-definitive, tentative light (thanks for that link).

Fuel is fed to the engines from the inner wing-tanks. For efficiency, in the cruise the CG is normally adjusted aft of the ideal for take-off and landing. On all A330s, the tailplane trim-tank helps, but I'll ignore that for the moment. This A330-200 also has a centre tank. This is, broadly speaking, forward of the wings, so is generally only used if the crew needs more than full-wings (71.7T) for the flight. In flight, it is emptied first, into the inners, which may also help with wing-bending relief. (Fuel will never be transferred from wings to centre tank.) In this case, the take-off fuel was only 70.4T, so the centre tank would have been empty throughout. In the climb, some fuel is normally transferred to the tailplane trim-tank, unless it's already full, pushing the CG aft by a suitable amount.

Wing-bending relief is also achieved by retaining full outer wing-tanks until the fuel in the inners is fairly low. When there's about 7T (tonnes) between the 2 inners, the 2 outers transfer their combined 5.7T into them. This does not happen until the trim tank has been emptied (via the inners). So at this point there is about 12.7T fuel remaining (< 3 hrs).
Normally, all this is controlled automatically (no grizzled flight-engineer...).

At the LKP, with nearly 7 hrs still to go to CDG, the fuel distribution should have been roughly as follows:
Tailplane full (4.9T) or part-full; *
Centre empty;
Inners part-full; **
Outers full (each 2.8T);
Vent Tanks empty (outboard of the Outers).

* According to the zero-fuel CG, and the current fuel distribution elsewhere, to optimise CG (relative to MAC).
** They were nearly full (all but ~0.6T each) at take-off, and would have been depleted to the extent of the total fuel burned (in 3:41 of flight) PLUS whatever was in the Trim tank at the time. (I think it would have been empty on departure.)

Hope this helps,
Chris