1) Open editor, load Stratis
2) Place yourself as a flying Independent > AAF > Air > A-143 Buzzard
3) Fly straight and level, go into the 3rd person mode and use your freelook key to move the camera around, observe that it behaves as expected, it looks left when you want to look left, etc.
4) Bank the plane to the right at a 90 degree angle and again use your freelook to look around
5) Observe that looking around now longer feels awkward, looking to the sides will now feel difficult and you'll most likely end up looking behind the plane in a snap fashion. Attempting to look up or down will still feel somewhat ok, but it will happen in a diagonal fashion
6) Bank the plane more so it's upside down
7) Observe that now attempting to look left will look right and look right will look left. Trying to look up or down will still work somewhat as expected but will try to fight you so that the camera also rotates.
8) Do a barrel roll!