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It is known that - for example - LaMia Airlines Flight 2933 needed to travel 1,605 nautical miles (2,972 km), which exceeds the range of the Avro RJ85 at 1,600 nautical miles (2,963 km). At what point in flight planning does the airline calculate and determine if an aircraft has enough fuel/range for its intended flight?

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    $\begingroup$ range depends on payload and fuel on board. where does the range computation appear? what data has been used for it? $\endgroup$ – Federico Nov 29 '16 at 15:38
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    $\begingroup$ There is no reliable information that it ran out of fuel. The investigation is just beginning. Claims that it ran out of fuel are based solely on the lack of an explosion/fireball on impact. Someone has been watching too many Hollywood movies. $\endgroup$ – abelenky Nov 29 '16 at 16:40
  • $\begingroup$ The article states that the pilots requested a hold to troubleshoot electrical problems. This tells me that fuel was not a priority at the time (unless they both didn't notice they were low on fuel). It says they asked for priority handling, but the article doesn't state the nature of the emergency. Unfortunately until the accident report comes out or transcripts are released, this is going to be pure speculation. $\endgroup$ – Ron Beyer Nov 29 '16 at 19:15
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    $\begingroup$ @KorvinStarmast, the question "when does the airline check to see if the airplane can carry enough fuel to reach its destination?" can be answered regardless of the status of LaMia 2933. $\endgroup$ – Mark Nov 29 '16 at 22:00
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    $\begingroup$ There is now (1 day after original post) credible information that the plane likely ran out of fuel, based on recordings of the crew's conversations with ATC. (cnn.com/2016/11/29/americas/colombia-plane-crash-investigation/…) $\endgroup$ – abelenky Nov 30 '16 at 21:26
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The spec-sheet range is not a fixed value—

  • The range of the RJ85 (BAe 146-200) is 1,570 NM with standard fuel capacity.
  • Range values are only valid for certain (marketable) payload/fuel levels.
  • If you have less payload and/or more fuel, you increase the range. Example here.
  • If there is tailwind, the [air] distance to destination is reduced (apparent range is increased). That's why marketed range circles are not circles, as shown below. Example here.

The wind may provide a head- or tailwind component, which in turn will increase or decrease the fuel consumption by increasing or decreasing the air distance to be flown.— Wikipedia

Corrected distance (after the average-wind is taken into consideration) is checked in the flight planning phase, and the plane is loaded accordingly (fuel and payload). If the aircraft can't reduce the payload to reach its destination, then a technical stop to refuel is planned.

Google Flights shows all the airlines stopping at least once on the way.

enter image description here

(Source) Range circles take into account the trade winds.

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The accident happened less than 24 hours ago, and any talk of fuel exhaustion at this stage is simply speculation.

The answer to your question is the pilots check if they have enough fuel to make the destination before every single flight. As others have said, the actual range of the aircraft is dependant on so many variables, that the quoted figure is effectively just a guideline for marketing purposes.

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    $\begingroup$ This doesn't at all answer the question, which is "When does the airline check if ..." $\endgroup$ – kebs Nov 29 '16 at 22:46
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    $\begingroup$ @kebs I disagree - the question specifically mentions flight planning which is completed by pilots, usually with assistance from dispatchers, who are all part of the airline, and completed before each flight. $\endgroup$ – Ben Nov 30 '16 at 0:00

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