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The diagram shows the B777-200LR Payload/Range for 0.84 Mach Cruise (P.41 of Source)

enter image description here

The maximum payload range is around 7600 nmi, and after that payload have to be reduced in order to increase range. While the Operating empty weight of 777-200LR is 320Klbs, the horizontal-coordinate(range) of the diagram is around 10500nmi at 350Klbs, and there is a gap of 30Klbs.

Does that mean B777-200LR has theoretical maximum range over 10500 nmi if OEW plus payload is below 350Klbs? And how far can it fly potentially?

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    $\begingroup$ Yes $\endgroup$ – fooot Aug 26 '15 at 21:31
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    $\begingroup$ Not really understanding the question because you have already stated the maximum range for the boeing 777-200LR $\endgroup$ – Ethan Aug 26 '15 at 21:38
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    $\begingroup$ @fooot - make that an answer. (Might need more than the one word, though... ;) $\endgroup$ – FreeMan Aug 27 '15 at 12:04
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The vertical axis starts at 350 Klbs since the Boeing 777 is made to transport payload, not just itself. Any operator will be interested more in the upper part of the diagram, because only then the aircraft will earn money. This explains the gap of 30 Klbs - the people for whom this chart was made are simply not interested in the range without payload.

The range varies with flight parameters, and the upper left corner shows the most important ones, albeit in quite imprecise terms. If the flight speed is reduced, range will become higher until the aircraft flies at optimum range conditions. Airlines like to fly their aircraft faster that that to optimize transport performance (the maximum product of speed and payload relative to operating cost). If power extraction and air condition are run at their bare minimum, again less fuel will be needed per mile of flight. Flown this way, the 777 will easily fly more than 10500 nm with a zero-fuel weight (OEW + payload) of 350,000 lbs.

To eke out the maximum possible range, high-density fuel is used and the aircraft is flown at an optimum altitude and speed for range. The records which have been set this way (11,664 nm for the 777-200ER), however, are of little relevance to everyday operation. The longest commercial flight of that type will be the Dubai-Panama City connection of 7,463 nm which Emirates will begin to serve on February 1, 2016.

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    $\begingroup$ Plus that nobody would be interested in flying any further than half the circumference of the earth. You simply fly the other way around... $\endgroup$ – DeltaLima Oct 31 '15 at 10:34
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    $\begingroup$ @DeltaLima: I guess that Boeing marketing will be very keen to surpass any Airbus record and vice versa, whatever the practical relevance of that record. But beyond those two organizations, you are absolutely right. $\endgroup$ – Peter Kämpf Oct 31 '15 at 10:36
  • $\begingroup$ @DeltaLima That would be true in most circumstances, but wind could theoretically make it faster to fly a bit more than halfway around if the city pair in question was already close to being on opposite sides of the planet. Flights from Asia to North America routinely fly hundreds of miles farther than the shortest distance in order to use the Northern polar jet stream, for example. Granted, it might be harder to find similar conditions on routes between near-antipodal city pairs. $\endgroup$ – reirab Apr 3 '16 at 5:40
  • $\begingroup$ @DeltaLima You also have to keep in mind that airspace isn't always available for use. So you may end up flying the "long way around" just because the shorter route has a war going on in the middle of it. $\endgroup$ – Jay Carr Jan 11 '17 at 18:08
  • $\begingroup$ @reirab, "shorter" here needs to be understood as airspeed times time, so tailwind makes the distance "shorter" and headwind makes it "longer". The chart only shows distance with no wind and wind correction has to be applied and is rather significant. And in that respect, the route with more favorable wind is "shorter". $\endgroup$ – Jan Hudec Jan 11 '17 at 21:00
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The longest official non-stop flight by a commercial jet was a 777-200LR flight from Hong Kong to London in 2005 (without passengers). It was 13,422 miles (11,768 nm, more than 21,000 km).

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  • $\begingroup$ Given that the two furthest point on Earth are 20037 km apart, this can't be correct. And the London - Hong Kong distance is far less, about 11000 km. The furthest cities are in fact 19996 km apart (Rosario - Xinghua) furthestcity.com So the range of the 777-200LR is just not enough between any two cities. But almost :) $\endgroup$ – Csongor Szíjjártó Jan 11 '17 at 16:03
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    $\begingroup$ @CsongorSzíjjártó The Wikipedia page (citing the NY Times article) clarifies that they flew eastward from Hong Kong, which is not the shorter route that you are measuring. $\endgroup$ – fooot Jan 12 '17 at 0:29

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