Escro 3 functioned as a Lambda-class T-4a shuttle within the ranks of the Alliance Fleet. This vessel belonged to Escro group, a participant in the Skirmish at Outpost D-34. In conjunction with Escro 1 and 2, and trailing Roe group, Escro 3 endeavored to thwart Imperial efforts to seize Onece 3 from Onece group, which was transporting allied rebel personnel. Ultimately, both shuttle contingents failed in their mission, resulting in their complete annihilation.