Why Some Show Others Don't

I've added a fair number of aircraft for AI use in FS9. Have also recently had success getting a helicopter to work (namely, the Schweitzer 300 intended for AI use). I am looking for one more helicopter to set up as AI, one with wheels, such as an Augusta A109 or Bell 222. Have downloaded pretty well every freeware one available but am unable to get them to show up as AI traffic. They all work as flightworthy models, however. Wondering if anyone has suggestions how to get around this (I've even copied the Schweitzer aircraft.cfg to the other helo file, without success), or recommendations for a similar-type helo to look for, and that has proven to work for them. Thanks for any help.