OK I just had to post this to see whats the deal and if anyone has this issue.On my MD11 (FS9 version)...when I am at cruise altitude just flying along...and the wind changes direction and/or speed (10 or more knots)...my indicated airspeed takes a huge drop!!! Example...Cruising FL350 wind is 100 @ 75...Same FL350 wind slowly shifts (in about 45 secs to 1 min) to 360 @ 100. During which time cruise speed goes from Mach .835 to hugging close to the yellow arc on the bottom of the indicator. The engines raise with full power and it makes it back up to Mach .835. There is no indication in angle of turbulence before anyone asks. Just smooth sailing other than the wind shift.Now also I have it when it shifts and I get an overspeed alert...but the drop is more common I find as of late. I understand a quick gust drop plus or minus but something like this I dont get.Any ideas???Capt Paul

This is an FS "feature" : As tailwind increases FS reports progressively lower IAS/Mach. When headwind increases then FS reports progressively higher IAS/Mach.That is how FS is programmed...Evidently progresively lower speed in your case results temporarily in higher angle of attack ergo MUCH higher induced drag and the engines have to be given time to accelerate the plane back to required speed. Near MAX ALT this will take some time.Vangelis

One workaround is to use the wind shift limitation function that FSUIPC has... you can limit the rate at which windshifts occur (x degrees of knots per second...), thus minimizing the effect...Andrew