altitude problem with stock planes

[flyingbullseye]

Does anyone know why all the stock planes except the 109 can not fly past 8-10000 ft?  At this altitude the engine cuts out and I know the ceiling was not that low especially for the stang.  If there is a fix please someone let me know.  

[ozzy72]

Have you tried adjusting your mixture? If you don't thin it out you'll loose it as the engine will flood and stall on you.

Ozzy

[Iroquois]

To go with what Ozzy said, under realism, turn on automixture. The computer handles the mixture settings for you allowing you to concentrate more on flying.

[flyingbullseye]

Thanks guys.  I feel stupid since I have been flying these flight sims for 2 1/2 years and it never came to mind.