60k extra fuel? Are you serious?
Yeah, not sure why thatās weird considering thereās a 3 hour flight time difference between the two.
At what speed do you cruise at?
Not sure how thatās relevant if Iām going the same speed both ways.
Well I always follow the speeds given for the corresponding altitude and there could be variations during step climb and I always try to round it off and hence for your final leg you will have enough fuel.
Also have you checked fuel used for your takeoff and climb?
Iām not OP but I donāt think you fundamentally understand the problem. OP is facing a near as much 70% increase in fuel burn over what is normal. He should be able to make ICN DXB carrying 118k lbs of fuel carrying regular load. He loaded Simbrief (195k), meaning an extra 80k roughly. He burned enough to need 230k, while carrying the extra 80k. An extra 80k makes his 77W go from 436k ZFW to 516k simulated ZFW, meaning he would need 137k for the flight itself. So, heās burning 230k for a flight that should take at most 140k, which is basically 70% more than normal.
I donāt think adjusting your mach by 0.01 during a step climb or climbing funny is going to burn an extra 90k pounds of fuel.
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Seoul to DXB is usually crosswind heavy route. Hence you gonna burn more fuel.
This might be ragebait but Iāll bite, that doesnāt matter because Simbrief would account for that.
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Well in that case it could be something else? I mean I pretty much fly on 777 and easily make over 20k fuel onboard after landing.
Yes, 70% is fairly similar to spoilers flight deployment (about 65%) or flaps 15 (75%). However, OP seems pretty professional and they have stated spoilers flush so I donāt think they would have either.
Okay so confirming that both SimBrief and Infinite Flight are set to kilograms, so no unit mismatch there. I double-checked that when setting up the flight. And yep, Iām Aussieānot American haha.
I use SimBrief for all my flights and havenāt had any fuel issues with other aircraftāthis has only happened with the 777-300ER. Iāll attach the full OFP from the ICNāDXB flight for you to have a look at. Appreciate you taking the time to go over it!
I wish everyone would have this much info ready when posting topics like this, thank you!
Just to confirm, you said you ran out with roughly an hour ETE left?
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Looking at your flight plan documents - your took 80t of fuel.
Even to use that entire amount in the 9h24m flight time equates to an average fuel burn of roughly 8400kg/hour, which is rather high, and considerably more than the average fuel burn Simbrief is stating in those documents of 7647kg/hour, even with a P02 fuel factor. Whenever Iāve done flights in the 777 in Infinite Flight, my fuel burn at cruise has never been more than 6500kg/hour.
If you are running out of fuel even before arriving, then we are getting into fuel burn territory of 9-10t/hour, which is absurd in the 777. Say you use that amount in 8.5 hours (running out an hour before landing) - thatās 9400kg/hour.
Something else is going on hereā¦
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Hahaha youāre welcome, Iām very thorough and OCD so that probably helps and yes I had around 1-1.5 hours left but only 25-35 mins of fuel time left
Do you remember what you ended up at altitude wise? I assume you started at 340 and ended 360?
Edit: nevermind, you said 342.
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Hahaah thatās what Iām saying, even though Iām not exactly following the step climb perfectly in the South Korea to Dubai, youād think it wouldnāt be that high even though Iām flying a little bit above at M0.86ish
Are you using flaps at cruise? Thatās the only thing I can think of that could even possibly result in that sort of fuel burn.
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Hahaha absolutely not, always take my flaps out of the equation after maybe 2-3 minutes from airport departure
Ok good 
Problem though is that makes this even more perplexingā¦
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At 342, 0.86 I am pulling about 7200 kg/hr at TOC and it would be roughly 5900 kg/hr when almost empty, so figure an average of 6500 kg/hr. In order to burn off 80.5 tons in 8.4 hours (1hr before landing) youād need to be burning 9600 kg, so 50% more than usual. The only way I can get the math to check out is 0.89 set on the autopilot, flight spoilers, or flaps 15. But since you said itās none of those Iām really not sure.
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