Reaching cruising altitude

I.e once you get to cruise you can put your trim at +100 or -100 or 0 and your range will be exactly the same

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I thought that but my bad 😅

Here are the things that effect your cruise pitch angle:

Altitude: higher alt → higher pitch angle (so it’s good you’re at FL300, that’s low compared to irl but it’ll help you out)

Airspeed: slower → higher pitch (again so .86-.91 is unrealistic but helps you with this.)

Weight: more weight → higher pitch (you’re not helping yourself with this one- the pax/cargo are just numbers on a slider. Don’t take any and you’ll get a more realistic pitch. Again you’re trading realism in one area for realism in the flight attitude, that’s worth it imo)

Configuration: this is the most egregious so I recommend using the previous three options. But if your flaps are down it’ll decrease pitch. Flaps 5 isn’t that visible but makes a very noticeable difference in pitch angle.

Hope this helps!

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You’re all good! Technically it should make a difference irl so your intuition is right. It’s just not modeled in IF at this time

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Your pitch problem is most likely due to how physics actually works. All aircraft have to have a very slight positive Angle of Attack (AOA) in the air in order to keep level flight. This is due to many factors including weight, altitude, speed, etc. If the AOA was zero or less than it needs to be in order to maintain level flight, then the aircraft would start descending.

From Principles Of Flight :
“…in straight-and-level flight, cruising along at a constant altitude, altitude is maintained by adjusting lift to match the aircraft’s velocity or cruise airspeed while maintaining a state of equilibrium in which lift equals weight.”


If you don’t want the aircraft to pitch a lot at your cruise altitude, I’d recommend step climbing. This will help burn off weight from the fuel, therefore requiring less positive pitch while on cruise. It is often more fuel-efficient as well which might solve your fuel problem. As mentioned above, trying different trim inputs might help a bit too.

Step Climb Guide by the one and only DeerCrusher:


Hope this helps :)

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A318: .78
A319: .78
A320: .78
A321: .79
A333: .82
A346: .82
A359: .85
A380: .85
B712: .76
B737-700: .78
B738: .79
B739: .78
B742: .83
B744: .85
B748: .86
B752: .80
B763: .80
B772ER: .84
B772F: .84
B772LR: .84
B77W: .84
B787-8: .85
B789: .85
B78X: .85

These are the cruising speeds I use.

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Ig it is because u kinda have too much fuel, try higher altitudes, ur nose may stay a bit up, that’s usual. Also, there may also be wind hitting ur plane

Sorry but i can tell you that it does when you set it up correctly it has impact to the fule burn its not much but it has and i know that because i made tests whil i am flying if in my 12.000+ flight hours i did tests like two devices fly on live both same route same Aircraft same wight one with the correct trim one without and the one with exact trim had more fule at the end.

I have done tests for this before by checking the fuel burn at different trim levels. If there is any difference it is neglegible (like less than .5%).

I should also note that your methodology is unreliable. IF’s autopilot does not show the third mach decimal place, so your two flight’s speed might be off by as much as M.01. This would have a larger impact on fuel burn than trim.

Yeah doesn’t just have a negligible impact: it has no impact at all. Trimming in IF effectively changes your accelerometer calibration point. When you’re in cruise on AP you can do whatever to your accelerometer and it won’t change anything.

Trim in IF just changes what the elevator is doing so when the AP is holding altitude it does nothing (once stabilized).

The DC-10 has good physics, and is a recent aircraft.

I always trim the aircraft until the magenta line disappears. That’s when the aircraft is trimmed appropriately, for older non-reworked aircraft this could mean ridiculous amounts of trim at the higher flight levels.

that happens to me all the time. check the flap limit online and maybe add some flaps. if that does not work, do negative trim. You are fine. you did not do anything wrong I believe.

Some trim may help you out. The pink line off to the side of the trim is showing what trim is needed

How much is the plane pitching up?

Yeah I think some newer aircraft actually animates the trim now but still no effect.