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There's an old saying that there's never too much fuel left in your tanks or too much altitude below you.

However, in terms of airline fuel planning, could there be a situation where an airliner would land with more fuel than is needed for its next flight, to the point that this extra fuel would be problematic?

Would this, or other circumstances, necessitate that fuel be removed from an airliner before a flight, for example due to a higher payload on the upcoming flight?

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    $\begingroup$ I have de-fueled airplanes for just this purpose, because the needed cargo or passenger payload with the current fuel weight would have exceeded the max gross weight. However, those instances were not airline flights, as your question specifies. $\endgroup$
    – J W
    Jan 24, 2016 at 19:36
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    $\begingroup$ Those old sayings are not much use in commercial aviation. There is such a thing as too much fuel. Take-offs are often made with "runway behind" or with tailwind components and so on. $\endgroup$
    – Simon
    Jan 24, 2016 at 20:55
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    $\begingroup$ @RalphJ -- it can also occur if the flight plan depends on the availability of a long runway to take off, and that long runway suddenly becomes unavailable (say due to winds, debris on the runway, etal) $\endgroup$
    – UnrecognizedFallingObject
    Jan 25, 2016 at 0:14
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    $\begingroup$ It can also happen when a plane scheduled (and fueled) for a long-haul flight is swapped into a short-haul flight; the plane may be under its max takeoff weight, but will be too heavy to land at its destination. (While waiting for a flight, I overheard a captain at the next gate trying to explain a defueling delay to annoyed passengers who could not understand how a plane can be too heavy to land.) $\endgroup$
    – Jeffrey Bosboom
    Jan 25, 2016 at 4:10

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This would be an uncommon situation and the decision on what to do will typically be handled by your dispatcher.

  • Take the extra gas and restrict passenger/cargo weight as necessary.

    This is the easy option but it could mean leaving people behind.

  • Defuel to the normal amount of fuel needed (e.g. release + taxi + contingency fuel)

    This normally means the fuel is considered contaminated and will be disposed of. There are ways of de-fuelling and re-using that fuel for another plane, but it requires specific operations and equipment that only likely to be available in the hub or perhaps a maintenance station. De-fuelling can be slow and will delay the flight.

In the end this comes down to either weight restricting the plane or taking a delay and wasting some fuel. The timing and economics of the decision will depend on many factors and each case would be judged individually.

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The people refueling the plane just subtract the amount of fuel in the plane from what the plane needs for the next trip from what I understand your question is. The other thing is that because the saying is true, airplanes come in with just enough fuel and not really enough to go anywhere else.

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    $\begingroup$ The question is, what happens if the result of that subtraction is a negative number. $\endgroup$
    – David Richerby
    Jan 24, 2016 at 18:25
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    $\begingroup$ So they would be in the side business of importing avgas? $\endgroup$
    – DJohnM
    Jan 24, 2016 at 19:30
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    $\begingroup$ @DJohnM Most airliners are turbine aircraft burning Jet-A (similar to kerosene), rather than AvGas (gasoline). $\endgroup$
    – J W
    Jan 24, 2016 at 19:37

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