Dear Mr. Mercy, I found the rudder of your MiG19's MDL has trim tab problem, which I think is from the old version of Yan Tao's MiG. Attached please find the 2nd version MDL. regards, Kuang-yu Lin (Taiwan) I tried this and it improves the roll rate significantly! To update the C model open the MODEL file in the Clean (MIG_19_clean) version right click on the mig19c.mdl file and rename it to mig19c.mdl.BAK and replace it with this one. Thank You, Kuang-yu.