Well, the flight models have good potential, but whomever made them, doesn't seem to really know anything about how planes fly except for hitting top speed numbers. AH or WB it is not. Out of the box, the planes are mushier than WB and fly as if they have no fin or rudder for stability. You will need almost full rudder input just to maintain a 45 degree bank else it will roll back level on you (dutch roll). I fixed that...
Yet at the same time, they were able to yaw over 45-60 degrees in some cases (the prop blast makes it worse), so I reduced the yaw angle a bit, to about 15 degrees, the typical angle that a thin airfoil would stall at...
When I first looked at the CFS flight models, there were cries of US bias and such, which I didn't really believe at the time. The P-51 weighed 7000 lbs full of fuel and ammo, for example, which is it's empty weight, IRL. Anyway, back to CFS2, I noticed the same kinda theme going on with the F4u and Hellcat models, so now I'm thinking they did this on purpose...shame really when they're supposed to be known for realism. I fixed all the aircraft weights and compression effects.
The flaps made no lift at all, so I fixed that based on clean/dirty stall speeds in the pilot's handbook. The landing gear didn't make enough drag, fixed that. The F4u had WAY too much WEP (over 10 inches, MP), so I reduced that. The P-38f was using 100 octane manifold pressures, so I fixed that for 91 octane rating. That's about it! Now, on to the AI planes!!