more nuanced sound to better judge engine status

Hey,

while i think the audio for the warbirds is decent and good enough to give you an immersive experience, i feel that it is not detailed enough to give any meaningful input to your flying besides power setting and rpm.

It would be great, if you could better judge the status of the engine by ear: in which condition it is - how smooth it runs, if you are mistreating it, if it is damaged etc.

I know, this is a very complex task, but it still would be very nice to have - especially with the new damage model on the horizon, that will probably introduce a little bit more complexity with engine damage modeling.

thanks!