The mission does not take place anywhere within the Joint Assault continuity, and is merely intended to test the players' skills.
Similar (if not, the same) in nature as the original Operation X from Ace Combat X: Skies of Deception, this mission pits the player against formations of all of the game's original aircraft, except the GAF-1 Varcolac. The enemy will attack in waves of two, except for the joint Apalis-Fregata formation at the beginning, and will spawn at different points in the map. Upon finishing the X-02/XFA-27 formation, the player will be attacked by a lone XFA and a FALKEN, which are, of course, a reference to Scarface and Z.O.E, respectfully. Also, a Fenrir named "Dandelion" will spawn southwest from the center of the map, and will proceed to relentlesly hunt down the player once in range. A word of warning- The FALKENs, unlike the ACX version, will not use the TLS on you. Z.O.E will, however, and he will actually focus the laser on you, doing immense damage in a small rate of time. Taking him out is top priority- he doesn't do any particular dodging moves, and simply flies around. Take him out or you run the risk of getting TLS'd while you go for the harder targets, such as Scarface or Dandelion. Scarface constantly dodges attacks and launches multiple missiles at a time, making him quite tricky to take down. Dandelion's Fenrir, thankfully, doesn't have anything spectacular about it (No camouflage, no HPM, no LSWMs) and can only do dodge maneuvers to your missiles.