Nose Down Cruise

I have read some current and older posts questioning why some planes cruise with a nose down or nose up pitch angle. Some have indicated this is due to incorrect physics. Some of these planes may have incorrect physics, but planes do not always fly nose level. I will explain.

A wing generates a certain amount of lift. The amount varies based on speed, altitude and flap configuration. The wing is designed to generate a specific amount of lift for typical aircraft weight, cruise speed and altitude. If a aircraft is traveling outside of the optimal lift envelope changing the pitch of the aircraft will be the only way to maintain level flight at a specific altitude, weight and speed. On some real world aircraft this can be compensated for by proactively loading passengers and cargo to change the center of gravity. Or it can be done during flight by transferring fuel to fore or aft tanks. If your plane in cruising nose up or nose down and you wish to correct it adjust your weight before take off or adjust your speed and/or cruising altitude during flight. Changing the lift characteristics by using flaps can correct a nose up pitch, but in real flying certain flap setting can not be used at certain speeds so it is typically best to ensure you are flying at the optimal altitude and speed to achieve a neutral nose pitch angle.

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Some commercial airlines do not cruise at a neutral pitch angle, but maintain a slight pitch up angle while at cruise. You shouldn’t be using flaps to control pitch at cruise.

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No flaps should never be used during cruise, however IF does not prevent this. Therefore some are using them outside of safe margined in IF that wouldn’t be possible in real flying. I wanted to express that yes this may achieve what you want in IF, but it is not a realistic solution.

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It most likely has something to do with the wings’ designed washout angle, engine thrust angle, and fuel allocation.

if you’re talking about the 757 and A388 it’s because their models are old and haven’t been touched. i believe staff are aware as well

The fore/aft cargo holds aren’t modeled differently in IF. Putting 2000lb in both is the same as putting 4000lb in one. The caveat is that a lighter load reduces cruise pitch while a heavy load increases it.

Unfortunately doing that increases efficiency and range for some aircraft in IF. As I see it that’s the real problem.

It is the delta between drag produced by the fuselage in a nose up pitch vs the drag produced by the flaps to achieve a neutral pitch.

Certainly. Load balancing would only apply to real world flying. Total aircraft weight is the significant item for IF.

When the physics break, the witches come out to play

Also. If you see the dash 8-Q400 the nose points down while on the ground so it also points nose down while cruising

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