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According to this question's answers, MTOW (or MTOM) is the Maximum Take Off Weight, which is everything up to and including trip fuel. Then there is one step above that, MRW, or Maximum Ramp Weight, which is MTOW plus fuel used to taxi out to take-off.

Can a plane be given too much roll-out fuel, so as the plane is actually too heavy to take off, without having to do perhaps another lap around the airport?

My thoughts are that there are simply no scheduled flights which require a total amount of trip fuel that would make roll-out fuel cause the plane to be too heavy for take off.

EDIT: Although (in a comment) I am asked to possibly change the title of the question to fit more closely (include fuel), after considering it, I've decided to leave it alone. It is unlikely that a plane would be loaded to the point that it is too heavy to take off, before fuel is added. I believe it would be a 100% certainty that it was the addition of fuel that will make (all)(commercial) aircraft go beyond MTOW. There might be some edge cases of contents (payload) being too heavy, but if that were the case the plane would not even be considered for take off (without fuel).

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  • $\begingroup$ You might edit the title of the question to make it a bit more specific, as the title questions stands it's very general (and the answer is quite clearly "yes", given no constraints). $\endgroup$
    – Jae Carr
    Commented Jun 25, 2015 at 19:52
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    $\begingroup$ @JayCarr I think the title's fine. Although the answer to the title question is trivially "yes", the title is only intended to be a guide to what the question is about. If it was always possible to make the title exactly describe the question, you wouldn't need anything else. $\endgroup$
    – David Richerby
    Commented Jun 25, 2015 at 20:59
  • $\begingroup$ @DavidRicherby That's true up to a point, but the title question is pretty far away from what the intent of the question is. All I'm saying is there are people who may want to ask that exact question, or who may be looking for the answer that exact question, and having this question have that title makes it a little harder for them. $\endgroup$
    – Jae Carr
    Commented Jun 25, 2015 at 21:02
  • $\begingroup$ @JayCarr I understand. I've considered it and have added a body edit. I'm leaving the title alone, because I do expect that the answer is yes. What I'm looking for is why and what then. If you can think of a 'better' title, please, do edit it. I'll roll back if I don't like the change. $\endgroup$
    – CGCampbell
    Commented Jun 26, 2015 at 12:43
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    $\begingroup$ From a historical standpoint, back in the 1990s, and especially on 747-100/200 cargo flights, it was common to "hide fuel" by specifying more taxi fuel than you knew you would use. Being a few thousand pounds over MTOW was not considered a problem. $\endgroup$
    – Terry
    Commented Jun 27, 2015 at 2:14

3 Answers 3

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It is possible to arrive at the runway with too much weight to takeoff, but this result is generally a mismanagement of fuel. The most likely scenario this happens is when you are going to be at MGTOW for takeoff but need fuel to get to the runway (putting you over MGTOW at the gate) and are anticipating a long taxi or long lines at a de-ice pad.

If the long taxi doesn't materialize this can result in getting to the runway with too much fuel. Recognizing this, fixing it is often as simple as taxiing with both engines instead of just one. If you are really overweight you just ask to get put somewhere you can wait while running both engines and wait for the weight to come down. There is really no benefit to taxiing around the airport versus just waiting in one spot to burn fuel.

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    $\begingroup$ This was exactly the scenario I had in mind, only couldn't come up with a use case (de-icing wait). Also, I didn't really mean a "go around" the airport, but guess I meant perhaps being routed on a return taxiway and looped back. $\endgroup$
    – CGCampbell
    Commented Jun 25, 2015 at 17:53
  • $\begingroup$ @CGCampbell ATC usually has somewhere close to the departure end of the runway they can let you wait out of the way. $\endgroup$
    – casey
    Commented Jun 25, 2015 at 17:55
  • $\begingroup$ How frequently might this happen, or is that a whole new question? $\endgroup$
    – FreeMan
    Commented Jun 25, 2015 at 18:44
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    $\begingroup$ @FreeMan not often. burning fuel is easy. More often (though still not common) the issue is getting to the runway with close to minimum or not enough fuel (requiring an amendment to the dispatch release). We are generally quite aware of the fuel situation and make sure to get to the runway with the right numbers. $\endgroup$
    – casey
    Commented Jun 25, 2015 at 18:46
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    $\begingroup$ AF 4950 was 810 kg over the maximum structural weight due to an unexpectedly short taxi prior to take off. Also the fuel was in the aft ballast tank, which should have been empty at take off until supersonic cruise. However the BEA did not think this contributed to the crash. $\endgroup$
    – Calchas
    Commented Jun 25, 2015 at 23:12
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Correct on virtually all points; it is possible for an aircraft with high payload or long range expectations to require more fuel be loaded at the gate than it could make it off the runway carrying; however, it wouldn't have to lift off with any fuel it needs to burn just to get to (or even down) the runway. The amount of extra fuel needed would be marginal; a couple hundred pounds at most, just a few minutes' worth at anything more than idle power.

You're also correct that the operator of the plane wouldn't be too eager to test these maximums with any fleet aircraft, and will have their own more conservative guidelines for loading an aircraft. These guidelines are typically only approached by cargo jets; people are relatively low-density given the amount of cabin volume required for each passenger. But, such limits are the reason, for instance, behind airline policies on number of checked bags (and the cost of each one) and the maximum weight of each one; more bags, and/or heavier ones, increase fuel requirements.

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    $\begingroup$ I thought bug policies where mostly about turnaround time and airport charges. $\endgroup$
    – Ian Ringrose
    Commented May 26, 2016 at 9:52
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    $\begingroup$ @IanRingrose: And airline profits. $\endgroup$
    – Vikki
    Commented May 2, 2018 at 15:24
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The MATOW (max allowable takeoff weight) isn't only limited by its structural weight limit (MTOW) but is absolutely limited by other factors. For transport category aircraft these other factors can limit max allowable takeoff weight.

  • Max structural weight
  • Brake energy for takeoff
  • Wheel brake cooling limits
  • Maximum tire speed
  • Required gradients for first, second and final segment climb to 1500' AGL.
  • Required runway distance to verify the takeoff weight will produce a runway distance below all runway declared distances.
  • Obstacles in the takeoff flight path

The pilot in command is required to verify they do not takeoff above any of those limits. The airlines have dispatchers that will calculate this information. If a mistake is made, it is possible to be loaded above the max allowable takeoff weight and not realize it. Most of the list above is accounting for an engine failure below or above the decision speed.

A popular runway analysis program (APG Genesis iPreflight) lists the limiting factors in their app that they use.

MATOW Factors from APG Genesis iPrefligtht IOS App

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    $\begingroup$ Have I understood correctly, that if the runway were e.g. 15 km long, MTOW would be the only limit in practice? $\endgroup$
    – Mikko Rantalainen
    Commented Oct 6, 2022 at 11:22
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    $\begingroup$ Well no. The runway length is only one factor to consider. If it 15 km long, you are still limited by obstacles, tire speed, turn radius, etc. $\endgroup$
    – wbeard52
    Commented Oct 6, 2022 at 12:46

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