Now for FSX from TweakFS is TweakAircraft. This add-on utility allows you to edit aircraft configuration files and change many settings for each aircraft in your FS portfolio. Click on Read More for the full story.
TweakAircraft is a user-friendly Aircraft Config File Editor that allows you to quickly and easily adjust hundreds of settings in each Aircraft.Cfg file ranging from Titles and Descriptions right through to certain flight characteristics, engine data, autopilot and special effects. Above all you can make any custom changes with complete impunity - TweakAircraft has an automatic backup and restore function.
If you've always wanted to be a Flight Simulator "aircraft mechanic" but were too scared to try in case you should "break" something, TweakAircraft helps by providing a safe environment in which to make/undo changes and guides you through the process with informative balloon pop-up notes on each Aircraft.Cfg file setting.