Hello out there! Is there a file that I can download to modify the air file in fsx? Also, What do I need to change in the air file to keep my plane from moving forward even when the brakes are engaged to make this plane from moving?

Sounds very basic.There is no THE air file in FSX, there are lots of them, for every model. I think AirEd from William M. Roth can help you, it's freeware. Just try a search.But I doubt that you have to edit the air file of any model to stop it from moving with the brakes on. The problem might be somewhere else here. Of course, I don't know which model you are talking about.

Hello out there! Is there a file that I can download to modify the air file in fsx? Also, What do I need to change in the air file to keep my plane from moving forward even when the brakes are engaged to make this plane from moving?

The product is "Air Wrench", version 1.01.89 by G W Beckwith

A better product is Aircraft Airfile Manager V2.2 as it is an actual airfile editor. Airwrench is a program that generates airfiles based on user input. It does not allow the user to edit the airfile itself and so it isn't what I would call an "editor". Using Airwrench to adjust one particular parameter in the airfile is impossible as Airwrench doesn't do this. Airwrench reads the airfile, allows the user to adjust some settings but not others which Airwrench sets and then produces a new airfile (which is usually of a different file size to what you started with).The OP may find editing the [brakes] section in the aircraft.cfg file for the particular aircraft a quick and dirty method of stopping the aircraft rolling. Increase the "toe_brakes_scale" = value to get more strength out of the brakes.