Saltair said,
Obaalspop said,
""I think you miss my point, indeed if you dump a tonne of cargo and uplift a tonne of extra fuel, of course you will still have that full tonne of fuel available to you at the other end."
This statement is not true. The tonne of cargo will weigh the same at destination, naturally, but the extra tonne fuel you carry some will be burned enroute, UNLESS you account for it in the fuel burn or carry extra fuel to account for that.
The statement, stating the statement is not true, is not true. Saltair you are not adding extra weight to the aircraft if you REMOVE a ton of cargo and add a ton of fuel. The aircraft will weigh the same at take off therefore the fuel burn to destination will be the same in both cases. As a matter of fact, the case where you have the extra ton of fuel will actually burn less because the ton of fuel is pumped around the aircraft to optimize the C of G thereby saving fuel (airbus fuel system).
You must account for extra fuel burn only if the resulting take off weight is more than the original flight planned weight.
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