Gents,I myself have posted this topic before (just two answers), and have seen many more. The trouble is that it is getting annoying...Flying from Stockholm to Paris CHG. Clear skies, real weather from FS9.After leveling at FL 360, exactly over Denmark, it started: speed (through VNAV)and ALT could not be kept, at all. Speed would jump to .988 MACH(!), than drop to .620, and the stick started that terrible noise. After very slowly returning to proper speed, the same would happen. That, of course, compromised altitude - and sometimes even heading.At times, it seemed to me that the winds were responsible, though I was using a simulation rate = 1.Whenever that was a slight wind direction change, it was prone to happen.This annoying behavior continued until starting descent.Now, guys, as I mentioned before, I have seen many topics like that before, but no "resolution" answer has been given. Answers vary from "try this" to just silence.Can we have a real rulling here?Regards from BrazilBPilot

This sounds very much like a rather common problem that happens with FS9 real weather. Typically this happens over open water or in areas of the world where weather reporting points are few and far between. It has to do with the way the progam interprets changes in the winds. It is unusual that it has happened to you over land, but the cause may very well be the same. Did this happen to you just once or multiple times? Does it happen consistently over the same place or is it more random than that? The answers to these question may aid you in solving the problem.If you have the payware version of FSUIPC you can usually solve this by setting limits on winds that shift in speed and direction. THird party weather generators have also been reported to have helped with this as well.Andrew

You should post some screen shots of your main panel when the speed issue is occurring.- Bill

I've been getting a similar problem but using AS6.After about an hour or 2 of flying, I get a speed problem. It gradually increases into the overspeed area.I have to manually intervene and disconnect the autothrottle, reduce speed manually and then re engage the autothrottle.Goran

I had the same thing happen on a flight from Seattle to LA, during my descent with engines at idle, -1000' descent rate, and "drag on" I dropped from Mach.85 to (I think about) Mach.50 then went leaps and bounds in speed gain until the aircraft broke up. (Upset at that) and as in the other case, using AS6. I did have the weather in MSFS set to undefined... which is what I think AS people say to do. There is an updated version of AS6 that I haven't tried yet though.Apologies in advance for neither answer or giving any new information, but I just wanted to add that I share in your grief.Bretthttp://www.precisionmanuals.com/images/forum/800driver.jpg

Gents-This particular problem within MSFS has been discussed at great length in this forum.... You can find previous detailed and digested answers using the search function!

I disabled aircraft overstress and damage in CF9 menu.

>I disabled aircraft overstress and damage in CF9 menu.I might be wrong, but it's my impression that at least the PMDG B747 complitely ignores those settings. I have tried to turn off collisions with other aircrafts, since I'm tired of being run over by AI planes, while starting engines or holding, but I still get a crash screen.Anyway, I myself had a similar problem a short time ago flying between Auckland and Sydney. Suddenly within very short time (within a couple of seconds) my plane went from cruise level (around FL350) to FL550. No wonder that overstressed was reported ;-)(I have to admit in cases like those above as well as at CTDs, I take the liberty of restarting the flight from the latest saved stage. I always save the flight before start of taxi and have autosave installed to take care of it during the flights)./ Jesper

I once got SPUN around like a dradle!! That was over Las Vegas, I used active sky and I blamed that for it...Are you using Active Sky?Boaz...

very common MS9 problem that occurs with every aircraft.Solution is hopefully FSx, but I have my fingers crossed for it!!

Captains,Thank you all for the attention to this thread. Answering some of the questions:1 - Screenshot (Melkor): I did not get one, mainly because I think it can't help. After all, the situation is simple: VNAV and LNAV on; altitude of FL 360; headwinds 21; a simple thing, but than it happens!2 - Weather(Morvious, Boaz, Callmecapt): I don't use FSx, AS6 nor Active Sky. Just plain old good FS9 real weather. Remember that it did not happen before the last patch of the Queen;3 - Tony Randazzo said there has been other threads in the forum... Any clue here where they are?My initial question still applies: is there a fix for this?Regards,BPilot