Somethings wrong with the 747-8

Device: iPad Pro 6th generation
Operating system: iPadOS 17.0.3

Hello everyone

So I am flying Frankfurt-buenos aires about 13 hours

I packed 8 hours refuel and I am low on fuel? I am at 29000 feet with Mach 0.82 (most fuel efficient I think)

So you packed 8 hours fuel for a 13 hour trip?

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No he packed 8 hours reserve fuel by my understanding

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May I know your total load %? And At cruise ideally you should be going anywhere between FL310 to FL410, as far as I’m aware, and cruising at M0.85, by any chance are you using any positive trim?

Seems a little over excessive however I’ve heard this plane has had fuel problems. So it’s actually quite smart on his part. @Lufthansa1 hopefully you’re able to do the flight at some point my friend.

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Yes true, personally, although I rarely fly any of the 747s, I never had any issues.

Well there was a guide for fuel burn and this was the result shown

Usually I found the other aircraft of this guide work for me in line with it, I don’t fly the 748 tho, but he’s going west so I think his altitude is fine. Maybe it’s the speed, but idk.

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Remember, Higher the Flight Level/Altitude, the more fuel efficiency there is

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FL280 M 0.85 is most efficient.

Seeing as you just departed, you are probably near 100% weight. At FL290 M 0.85 90%, you will burn 32k lbs/hour at M 0.85 which means you will show about 12.2 hours of fuel (which is short). However, the 748’s fuel burn drops off a cliff as you get lighter, to the point where you’ll be burning less than half that when empty. I did the math and with 21 hours of fuel packed you will make it no matter what, as long as you drop to FL280 and increase to M 0.85.

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@Lufthansa1 I recommend based off my knowledge so I may be wrong, there’s more people on the IFC with more knowledge than me, that you climb to at least FL319 and cruise at M0.85, climb at M0.83 and use some negative trim if the aircrafts AOA (Angle of Attack) is too high.

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Yup but I think the 747 model might be a little flawed- not taking the fuel burn guide as gospel, but it gives a pretty weird discrepancy when flying west or east. Regardless, you’re right about that when it comes to the newer reworked aircraft imo, but again I never fly the 747 so idk how accurate this is with regards to the sim

Speed up, but don’t climb. Climbing a 748 usually results in extra fuel burn. Also, trim has 0 impact on fuel burn, I’m not sure where this rumor came from but it’s not rooted in fact.

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As Andrew nicely said, he’s more of an expert than me, I’m not much knowledgeable about the 748

Probably the best advice, it was your guide that I pulled the pic from lol

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Glad people are actually using it lol

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Ahh okay, I saw somewhere that it can affect the AOA which therefore affects fuel flow and burn but that was the 787, sorry for the confusion

The trim just affects how much pressure the computer puts on the elevators, but AoA remains the same.

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Tbh it’s been a life saver for me especially with long hauls cuz it’s a reliable way to know what altitude to use and when to step climb etc

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Oh okay, Thank you for the info! Good day/Night :)

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My flight will land in 5 hours with 4 hours left. I think the wind changed to tailwind and that’s why i need less fuel

Still kinda confusing especially when im doing ultra long hauls like this one