Hello Nebula, thanks for you reply. In the mean time I also found that WorldViz Vizards, VR Eye tracking analytics lab has also capable of extracting the eye tracking analytics.
So and there are some software's claiming that capable of analyzing eye tracking data for a good price and also some SDK's. I am not an expert in programming but at least have basic knowledge on general aspects.
My plan is record eye tracking data of users in a 15-20 minutes flight simulation(Xplane or Prepar3D) session, and thereafter analyze it. It seems to be more complicated than I thought.
Now at least I know that it is possible, so the right thing to do from my side is buy the product start testing it.
Thanks again.