I'm guessing if everybody had been on XP10 you wouldn't have seen the issue
Hey Tim,
Not sure I agree with that conclusion about X-plane 10. I think it is MORE likely to occur with X-plane 10.
I am running X-plane beta 10.20b11 (32-bit). I just ran a test flying a Beech Staggerwing. I can never get this plane above 20fps and for most of this test I was getting 12-15fps. I ran a 10 nm route as determined by a measured course on Foreflight. I timed the 10 NM leg at 4 min 29 seconds in real time. That works out to a groundspeed of 133kts. During the entire run, both indicated airspeed and indicated ground speed on Foreflight were 205kts (I assume this is what would have been reported in PE).
I believe that by decoupling the flight modeling from the visual system, when resources get low, X-plane is favoring keeping the flight dynamics accurate, even at the expense of flying in real time. So if my crappy laptop were to race Keith's new system in identical complex aircraft in a heavy scenery area, he would arrive well ahead of me, but PE would show us both traveling at the same speed......I would just take longer to get there!!!
This messes up any chance for doing good ded reckoning if the frame rate is below 20fps. It would be nice if the onboard clock would correspondingly slow down but it doesn't (I checked).
It's enough to make Einstein rethink his theory of relativity