A programmer from another of Hitech's games came up with this info in 1997. For AH purposes it's dated but, closer than Tank-Aces guessing "Corner Velocity" instead of looking for something on the Internet.
BF 109-K4
-CornerVelocity: 275mph
-CornerRadius: 551ft
-Sust.NoFlapSpeed: 170mph
-Sust.NoFlapsRadius: 817ft
-360degreeNoFlaps: 20.6sec
-Sust.FullFlapsSpeed: 140mph
-Sust.FullFlapsRadius: 657ft
-360degreeFullFlaps: 20.1sec
P51D
-CornerVelocity: 270mph
-CornerRadius: 531ft
-Sust.NoFlapSpeed: 165mph
-Sust.NoFlapsRadius: 789ft
-360degreeNoFlaps: 20.5sec
-Sust.FullFlapsSpeed: 145mph
-Sust.FullFlapsRadius: 731ft
-360degreeFullFlaps: 21.6sec
Source:
http://www.rdrop.com/users/hoofj/corner.htmGonzo's page seems to have java exploit popup at the moment.