The game's prologue (and tutorial) concerns Ace's "family missions" in which his elder family members and Emkay instruct him in the flying of Corellian transports so that he can begin working for the family.
These missions reveal that the Azzameen family are in heated competition with the Viraxo and are generally sympathetic to the Rebel Alliance. Due to their sympathies, the patriarch of the family, Tomaas Azzameen, smuggles bacta for the Alliance in the aftermath of the Battle of Hoth. This causes them to pay dearly as the Galactic Empire raids their home station for running bacta to an Alliance outpost. The family subsequently seeks asylum with a Rebel task force.
As a Rebel pilot, Ace participates in a variety of missions for the Rebellion while also helping his family fight the Viraxo. During his tour with the Rebel Alliance, he proves himself to be a significant pilot as he participates in missions that uncover new Imperial projects, such as experimental TIE fighters and the second Death Star.