Jason290

Forget the calculus for a moment and think about it in terms of what an airspeed indicator's job is. As I see it, the two most important jobs it does are, (1) at the low end--help you to keep from stalling, and (2) at the high end--help you to keep from ripping the wings off your aircraft. So in the latter case, what it's really telling you is how much stress there is on the airframe! At any given speed, the thinner the air, the less stress there is on the airframe; and for that reason, the higher the allowable max speed. Doesn't that make logical sense?

If anybody here flies a real-life King Air C90B, it would be interesting to hear how the overspeed barber pole moves when altitude increases. In other sims I have flow, it increases as altitude increases, which makes sense because the air is getting thinner. But in the Carenado sim, it decreases as altitude increases, which makes no sense to me.