OpenVSP 3.52.1. Strange values of roll , pitch and yaw moments.

[Mike Novikov]

Please check out this simple plane case that I made to demonstrate the strange behavior of the plane's moments.
The pictures show the results of runs with two different tail deflections (10 and -10 degrees).
I expect that with β = 0 (the geometry is symmetrical), I will get the same magnitudes for all moments, but the roll and yaw will have opposite signs.
As you can see, even the pitching moment differs by 18% in magnitude.
Could someone explain where I am wrong? 

[Mike Novikov]

For version 3.49.0, the difference in moments is much smaller!

понедельник, 21 сентября 2026 г. в 17:17:14 UTC+4, Mike Novikov:

[Rob McDonald]

I've pushed up a 3.52.2 with a fix that might also be this -- please give it a try.

Rob

[Mike Novikov]

I checked version 3.53.0. It looks like the difference is within 10% for the test case (I updated the panel distribution a bit to make it more feasible: Test2.vsp3).
For CMytot, the difference is still 10%; I believe that's a big value.
In a different (more complex) project, I got a difference of up to 24% in Cmxtot and 19% in Cmytot.

Should I try 3.52.2?

четверг, 24 сентября 2026 г. в 07:58:21 UTC+4, Rob McDonald: