It participated and survived Operation Trinity in the Bilbringi system. When the fleet jumped into Bilbringi, it was supposed to transmit the system's weak spots to the other waiting fleets, but the Yuuzhan Vong in turn launched the Mabugat kan, which crippled several HoloNet relay stations. Alpha Fleet was then stuck in the system without reinforcements and heavily outnumbered.
It was only due to the tactical brilliance of Wedge Antilles and the timely seizure of a hidden Golan II Space Defense SpaceGun by Han Solo that the Fleet managed to survive the engagement.