I don't even know how to use time acceleration in DCS. When you're used to flying a 747 across the ocean at around Mach 0.84, getting from one end of the map to the other in DCS at Mach 1+ doesn't really seem like it takes all that long. ;)
It's all 1:1 speed. Things seem to start normally - this last time, the first time I shoot at him is accurate (I fired on the lead pass to verify that the track I was watching was, in fact, the track I just recorded). Then there's half a minute or so of turning and by the time I shoot the second time, I'm not pointing anywhere near him. Just firing at nothing. Then a little later I slam into the ground. What really happened was that I shot at him in the lead pass, got into a turning fight, ended up behind him, and shot him down, then ended the mission and hit replay.
I can understand why I might not be aiming at him in the replay because maybe it calculated inputs differently enough that we're in different positions, but I'm kinda surprised that it would get off on the altitude by several thousand feet to have me hit the ground.