I am still in the testing process, but there are some problems with the behavior of the flight model, in my opinion.
It seems the earth effect is not working correctly, or wing and flaps lift and drag coefficients nedds to tune.
Try to explane. When taking off and after the aircraft leaves the ground, it tends to lower its nose, with a pitch of about 10-15 degrees. At the same time, a significant consumption of the steering wheel in pitch is required, up to the point that the steering wheel comes to an emphasis on itself. V1, VR, V2 are calculated according to the take-off weight and alignment.
Similar behavior of the aircraft and on landing, in some cases, a significant consumption of the steering wheel is required by pitch on flare, up to the point that the steering wheel comes to an emphasis on itself. Similarly, the speeds correspond to Vref. Sometimes it is necessary to flare the aircraft with the thrust of the engines, not on idle
Although according to the datarefs of the Xplane itself, the earth effect is present and is worked out by the model.
On the other hand, this behavior of the flight model is quite interesting )), since it is necessary to break the established stureotypes on takeoff and landing and take into account the new behavior of the flight model.