I recently made the switch from FS9 to FSX. I've been flying on VATSIM for 10 years, so I know what I'm doing. I have ActiveSky 6.5, which seems to work fine.My problem is that I'll be flying along on autopilot, no worries, no issues. The next thing I know I'm in a nose dive or a stall or the plane is spinning wildly out of control. I have plenty of fuel. I'm not too heavy. I didn't climb too high. It just happened again as I was climbing out of KMIA at about FL250 in a 737.It's happened in multiple aircraft, both default and add-ons. It's happened with ActiveSky running, and without it running. The only thing that's the same is it happens almost every flight. I've attempted 6 flights in the last week, but only completed 2 due to this issue.Anyone have any clue what's going on here? Getting very frustrated and thinking of going back to FS9.Here are my computer specs:AMD Athalon 64 X2 Dual Core 5200+ECS NForce mainboardWindows XP w/ SP3 installed (but it happened before SP3 also)2 GB RAMATI X1900GT Video Card w/ latest driversSoundblaster X-Fi Xtreme Audio

Does it happen without autopilot engaged? Have you tried an alternate controller device?ArtBiostar TF560-A2+, Athlon 64X2-6000+, 4GB RAM, Geforce 8800GTS-320MB, 500W PSU, 250GB HD, FSX (SP1-SP2), Vista Home Premium 32 bit, CH Yoke & Pedals, 22" WS LCD monitor

Wind shift issue?It's well known & discussed that FSX has brutal wind shifting since RTM, sometimes 180 degree in a second throwing your plane all over the place when you cross the layers. Is it related to this possibly?Pete Dowson has updated his FSUIPC to 4.28, and this last version he was able to smooth things out for FSX, via his 3PD offerings.I'd give that a try, if your not already using the latest version.Regards'Garett

Art: I don't know if it would happen with the AP off, but I'll try it. And I don't have any other controllers, besides the keyboard, so trying something else is out of the question.Garret: I suspected it was a wind issue. I posted this thread to see if anyone would back up that theory. I had FSUIPC 4.26, so I'll go try 4.28. If that solves it, I'll post that info.Thanks for the responses guys.

Please tell me the cure, I just had it happen climbing out of KLAX at about FL365 in the default 747 with A/P on.

If I figure it out, I will. About to try another flight, my first with the new version of FSUIPC.

I still have the problem, but it didn't seem as severe this time. I think if I played with some settings, I might be able to get that under control.Now I'm getting "your computer has run out of memory" and FSX shuts down without giving me a choice. I know 2GB is low, but it's not that low?? I get plenty of frames on the ground and in the air. How can I be out of memory?GRRRRR! Back to FS9 I guess.

I've had this happen as well. FSX apparently assigns a desired altitude for each waypoint and it defaults to the cruise altitude. The AP is determined to reach the desired altitude at each waypoint, and your AOA will increase the closer you get to the waypoint, until you finally stall. The two solutions I've tried are: don't turn Flight Director on until you are near cruise alt, and the other is set realistic altitudes for each waypoint during your climb-out. I haven't figured out how to do the second one with preset intersections as FSX apparently only lets you set altitudes with custom waypoints.

Out of memory can be fragmentation or virtual address space related, try turning down your settings or using the /3G switch.

Since this windows install is a month old, I doubt it's fragmentation, but I'll defrag today to be sure. Since I only have 2G of ram, would the /3G switch matter?

>Since this windows install is a month old, I doubt it's>fragmentation, but I'll defrag today to be sure. Since I only>have 2G of ram, would the /3G switch matter?Just the act of installing FSX causes hard drive fragmentation...Yes. As has been pointed out many times, virtual address space has nothing to do with physical memory... :)

memory fragmentation can happen for a variety of reasons; other apps chewing up memory, FSX running for a while chewing up memory, etc. if FSX cannot find a contiguous block large enough to satisfy the allocation request to all intents and purposes it sees the situation as "out of memory".that is totally different than disk fragmentation, which tends to only slow down FSX.as far as /3G, as has been said many times that is for virtual address space and is completely independent of physical RAM. 32-bit processes get 2G of virtual address space, the /3G switch relaxes that restriction. N4GIX ( Bill ) has a great explanation of this. without relaxing this restriction if FSX hits the 2G limit that is also seen as "out of memory".

Thanks for the explanations guys. The drive was moderately fragmented, so I just finished up a defrag. I'll check out the /3G fix as well.Will report my next flight when I get around to trying it.