The wingman AI in Ace Combat 5 is remarkably passive for the most part. Edge, Chopper, Archer, and Swordsman will keep running their mouths off, but most of the time they won't attack the enemy even when ordered to, and the only special weapons they're willing to use are the SAAM, QAAM, XMAA, and XLAA.
The wingman AI was improved in Ace Combat Zero, but not by much. At least Pixy actually follows orders and is aggressive enough to use all the special weapons. P.J., on the other hand, seems to be so preoccupied with aerial targets that he won't engage ground targets (not even with guns or regular missiles) even when ordered.