[Atraikius]

Is it possible to create a fighter design using the drone design name (I don't plan to use drones, so there is a unused design name) :

Name := DUC Interceptor
Design Type := Anti-Ship Drone
Vehicle Type := Fighter
Default Strategy := Fighter Attack
Size Minimum Tonnage := 10
Size Maximum Tonnage := 5000
Num Must Have At Least 1 Ability := 0

Should work fine, I used to use Recon Satellites to do the same thing until a patch durring the change from 1.49 to Gold prevented the AI from building more than 1 Recon Sat per turn on each planet. Try looking at your fighter files some more, I've seen some AI's building multiple fighter designs without a problem.