I wouldn't be so sure about saying no. I believe radar did have a maximum altitude, but I'm not sure about now.
Maybe it was a bug or maybe it was by design, but I do remember that if you coaxed a plane up to XX,000' (I want to say 32,000', but I just can't remember clearly) no bar or dot would appear on radar, but fields and strats would blink.
It would be fun if HTC would answer a few of these kinds of questions once in a while. Unlock the 'mysteries' of Aces High...
