What effect does Frame rate have on flight ETA. Sometimes a 2 hour flight last 3 hours. Dave

The difference between real and sim time is a problem since FS2000. That's why there are several solutions like FSUIPC sync time, FSINN sync time etc.But a 2->3h difference it's new. Did you check with a simple distance=ground speed x time formula?Jos

Frame rates should not have any bearing on ETA's...Theoretically speaking, if you are flying at 100 kts for 60 minutes, you should travel 100 nautical miles, whether or not you are getting 10 FPS or 60 FPS. :) In the simulator, the clock should move in real time. You can "time" it to see that it does by setting your simulation clock to the same time as your *actual* clock in your room. Fly a flight without exiting the sim or bringing up any secondary menus or options, and don't use any time acceleration. Your in-game clock should match up with your *actual* clock when all is said and done. Flights are of course influenced by winds - if you are flying, be certain to check for winds aloft - even the basic weather settings may introduce winds at altitude that could be slowing you down. -Greg

It is a known fact that the FS9/FSX clock runs slower then the computer clock. This is why FSUIPC has a option to keep the clocks in sync. The drawback to these Utilities is when the FSX clock updates every so often it will reload FS. Not a real problem unless you run a lot of 3rd party AI FP's and Planes.What will cause the FSX clock to get behind faster then its normal phenomenom is very low FPS. This causes studders which stops the clock momentarilly. The lower the FPS the more studders and the further the clock falls behind.If you are falling behind one hour per three hours you might want to check your time zone files. There are downloads available here on AVSIM that fixes the World Time Zones in FS9/FSX. Some time zones lose a hour too soon in FS9/FSX making it appear that your flying time is to long. Of course as already stated above, real world weather with high head winds can do the same thing.

Do you have "pause on task switch" unchecked?