Yeah, that's what I was getting, too. Ya know what? I'm going to runs some tests in KSP to see what Mach .92 is at various heights. Good thing I've got an F-104 to help me! I'll be right back. - - - Updated - - - Ok. 100m = 325 max 500m = 320 max 2000m = 313 max 3500m = 305 max 5000m= 300 max 7000m = 285 max 8500m = 275 max 11000m = 275 max Seeing as the speed at 10000m is ~275 m/s, I'm inclined to keep the max speed the same. What I will do is clarify the scoring a bit: Be subsonic in level flight @ 10 Km Max Speed @ 10 Km is 275 m/s (+15) Cruising speed @ your cruising altitude is 275 m/s (+15) Speed Limit: During level flight @ 10 Km, go faster than 295 m/s (-10) Definitions: Level Flight is flying with +/- 10 m/s vertical speed Operations @ 14 Km means taking no more than 30 seconds to do a 180 horizontal turn