Try opening the aircraft cfg. file of the offending aircraft,look under the section [Flight Sim] and find the lines; ui_manufacturer and; ui_type they should look like this example of a boeing 737,
ui_manufacturer=Boeing ui_type=737-300-FFX
if they are blank or incorrect ATC will refer to the aircraft as experimental. Hope this helps. arthurplum
No, it really has nothing to do with the ui_ stuff. The UI stands for User Interface and controls where the aircraft shows up in the list.
What you want to change is a small line under the heading [General] usually located just under the [fltsim.x] entries. Look for atc_type= and change it to whatever you want. Now be sure to note that not just any assignment there will be understood by the program. There is a specific list of types that you can enter here. For more on this, and a list of all the entries you can make, go here:
must have been asleep when I drafted my reply.Ender Baron is spot on with his solution. Have included the correct example for the 737 which is found under the [General] section of the aircraft cfg. atc_type=Boeing atc_model=737 Sorry if I confused you, Arthurplum.