The topmost part of the Airplane Customization dialog will give some information about where GSX is taking data for the currently loaded airplane from....screenshot...The first lines labeled “Aircraft data available from these sources” will list all valid data sources found for this airplane, and the next line, labeled “Aircraft data used by GSX” will tell which, of the various data sources available, is used by GSX right now....The Internal GSX database indicates this particular airplane has been included in GSX, so it’s usually ready to use without any further changes, but of course itcan be user customized too.