737NG acting irratic

If you are talking about the DWC (DirectWind - weather? - Control) as when used with FSX so you get weather smoothing it forces Global Weather Mode. That means as you are flying the weather in the entire FS universe at that moment is the same as for your aircraft - not a good idea when using ATC that looks at AI when assigning runways on contacting approach. In FS9 you can get weather smoothing using ASE by letting FSUIPC3 do the smoothing and Global weather control is an option but not required.The extensive ASE manual I looked at some time ago in support of RC users had recommendations on setting FSUIPC to control wind shifts. ASE makes those features available by registering itself with FSUIPC.I don't use real time weather but download the archived snapshot for the Z time and date of my flight so the effects of time of day (solar) and season are correct. I use FS time in my flights. Now I use AS6.5 just to be clear. You get better results by loading your flight plan into it, processing it, and for setting up your aircraft parameters doing a full printout of the AS navlog which shows METARS and winds aloft along your route, handy for FMC performance parameters.Finally there recently has been a service pack update for ASE to improve performance and also for ATC programs to get destination weather as it should appear when you reach it. It also requires an FSUIPC update.In FS9.cfg there is a global setting for turbulence that can also be decreased. (This dies not control the degreee of wake turbulence.) In the [weather] section I have mine set to:TurbulenceScale=0.300000If you edit FS9.cfg make a backup first.