Or is there another possibility to do these things?
Yes, you can manually create and edit an airport "TAP" file.
After you create the TAP file for your airport you can then use aerofly FS4 tap converter to get the scenery files (*.tmb, *.toc,*.tsc and *.wad) needed to be placed in your "Documents/Aero Fly FS4/scenery/airports" folder so you can see your creation.
Creating and manually editing tap files is a time consuming task at first but once you get the hang of it it's a pretty straightforward process.
You can get more info about tap files in this thread by ApfelFlieger: