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I'm new to flight dynamics programming and am curious to know how people model an aircraft's resistance to rolling in very simple force-based flight models (not CFD, etc.). For example, after a full deflection of the ailerons, the stick is returned to center and the aircraft will stop rolling.

I assume I should be looking at factors including dynamic pressure, wing area, and a center of pressure for the wing. I'm just not sure if I should just be modeling the "wing pushing against the air that it is rolling into" or if there are other more significant physical principles at play.

Essentially I am trying to create a model in which I can tune maximum roll rates against an aircraft's tendency to want to stop rolling.

Thanks, and sorry in advance if this is too vague, but any info will certainly be appreciated and will help steer me.

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The way this is commonly done in simulators is using linearized stability derivatives. For your example, one could calculate the rolling moment on the aircraft as the sum of such terms as: rolling moment due to aileron deflection angle, rolling moment due to roll rate (roll damping), roll moment due to side slip angle, roll moment due to yaw rate, roll moment due to rudder. For doing simulation each of these coefficients can be precalculated based on flight testing or CFD and then during simulation lookup tables can be used to find the current value. My suggestion is that you take a look at JSBSim which is a cross platform opensource flight dynamics model that is used by FlightGear for example. JSBSim allows one to build an aircraft model by defining the values in an XML file. The website includes documentation, some links to papers and books, and example aircraft that are very useful.

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  • $\begingroup$ Thanks! That's the basic approach I take, although a bit simplified as this is for a mobile game. Basically, I'm adding new terms to the model as it gets more sophisticated. I don't need precision, I just need it to "feel good" and allow me to differentiate between aircraft. I've looked at JSBSim and LarcSim in the past as references, but it takes me a while to digest the math ;-) $\endgroup$ – Matthew Harmon Dec 2 '20 at 19:44

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