Hey,when you delete an AI Aircraft in FS2004 it seems it's still flying around as a ghost. Because it's still listed in the flightplan FS2004 does not realize it's gone from the harddisk.True ?

No, if the aircraft file is not available, the AI engine will not use those flightplans calling that aircraft. The AI engine will search the flightplan file for other aircraft with all the parameters met. In other words, substitute a different flightplan that may not be seen if too many flightplans are available for a particular area.If you only had a small number of flightplans for a particular area, then the AI engine wouldn't substitute another flightplan since there wasn't any to meet the distance/time criteria (approx. 90nm from the default aircraft location). In this case, you would have less AI flying since the missing AI aircraft flightplans wouldn't be used.W. Sieffert

If you delete and aircraft and it STILL appears in the simulator for the AI flight, then you have more than one aircraft with the same title= . . . line in your aircratf.cfg files. be sure you do not have duplicate entries. :-)I had the same issue once trying to get rid of an aircraft MDL that was causing my simulator to crash to desktop. Turned out I had two identical entries for that AC in the CFG file and deleting one just made the simulator use the duplicate.Knik