Does this mean that 777 is using real world data, but somehow the equation is wrong, so using accurate data results in inaccurate FM-s? Because they always keep saying this is the data they have, therefore the FM-s are correct. Looks like it is not the case, then?
Great work by the way, I can't wait to try your Dr1, and I really hope 777 will decide to review the RoF Dr1 accordingly.
It is a very logic approach, but it also highlights the tremendous difficulty in creating a routine that translates real world profile data into actual flight behaviour. You have to cut an awful lot of corners to do that, as you don't want to overload your system with calculating aerodynamics.
For instance, XPlane was specifically programmed to be able to compute aerodynamics more acurate than other sims. But even they have to cut corners as any other sim, because also they cannot max system load with aerodynamic comutation. After all, there is still a world out there to display. Some say, their engine is superior, but looking at the final result, I'd say "it depends".
But if you are designing an airplane, you use a supercomputer to depict airflow alone to get it right. By limiting computing ressources, the computed result will diverge from the real thing. This is why it is absolutely required to follow up with fine-tuning your sim aircraft. In FSX there is a good example for that: use the stock Cessna 172, then compare it to A2A Accusim Cessna172. They share very little in their flight model except for respective speeds (to some degree).
After learning from you Chill, I'd be tempted to try to "heal" some of the Camel that is (as freeware) out for FSX... Going through the material presented here in this forum, I suspect the exaggerated aileron effectiveness and yaw stability as well as undermodelled adverse yaw (basically across most of the planeset) to be the largest deviation from the real flight characteristics of those planes.