Ustio Air Force

Overview
The Ustian Air Force had a somewhat short life span. After their country was established they became an immediate target for Belka and were invaded during the Belkan War, in 1995 (Ace Combat Zero: The Belkan War). Most of Ustio was overrun by Belka and the Ustian Air Force was almost completely wiped out. The Ustians turned to aerial mercenaries to defend the last free territories of the nation and eventually played a large role in the Belkan War's outcome.

Squadrons
Crow Squadron Aircraft: F-16C Fighting Falcon

Galm Squadron Aircraft: F-15C Eagle
 * Main character's aircraft is changed as they feel and the story line also changes formation

Source
Ace Combat Zero: The Belkan War (the game itself) Ace Combat 05: The Unsung War (the game itself)