Fort Norton does not appear much in Ace Combat, but it nevertheless is an important location in Ace Combat 6: Fires of Liberation during mission 12, Weapons of Mass Destruction. The fort does not seem to be too heavily guarded, except for a few light anti-air defenses in its vicinity.
In the mission, Fort Norton is the secret location of the enemy's WMD catalyst. Garuda team secretly flew in the canyon at low altitiude, arrived at the fort, and destroyed the enemy's WMD catalyst transport squad.
Apart from this, not much else is known about Fort Norton.