You could create a 3D Studio "object" using terrain data and import that object into Realflight as the "ground" for your new airport.
Most of this is beyond the scope of these forums....
e.g.
Using 3D Studio
Importing GIS data into 3D Studio
Creating a 3D Object from GIS data
etc., etc., etc.
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Satellite images are unsuitable for airports as they are merely 2 dimensional flat representations.
The big reason for going through the effort is to accurately reflect elevation changes, which you can not do with 2D images alone.