what most aircraft suffer from is simply dynmaic pressure from the airspeed on the control surfaces making them very stiff and hard to move.
The only birds that actually have compression effects right now are the P38 and the P47. All the others are sipmly the dynamic pressure from moving through the air at high speed
Funkedup posted a novella about the difference between compression and dynamic pressure, and can explain it much better than I can. Do a search on the name funked in this board and the gameplay/feedback board, then select threads he has posted to w/ compression topics.