FS2004/FSX – AI Aircraft Editor 2.1.18 is a program to view, edit and validate FS2004 and FSX aircraft. It allows easy renumbering, modification and deletion of [fltsim.x] sections, modification of wingspans and the aircraft type in the .air file. Newly added is a model viewer that shows the currently selected model and texture. A detailed manual is included. The Owls Nest Tools. By Martin Gossmann.