The Denab conflict occurred in the early stages of the Galactic Civil War, before the Battle of Yavin, and involved the Rebel Alliance facing off against the Galactic Empire's Imperial Fourth Attack Squadron in the Denab system. This clash was a component of General Jan Dodonna's larger effort to demonstrate the Alliance's starfighters as their most adaptable military resource, showing that their strategic application could secure triumphs and weaken the Empire's dominance in space.
The confrontation started when BTL Y-wing starfighters, led by the Rodian commander Grisserno, launched an assault on the Victory-class Star Destroyers of the Imperial Fourth Attack Squadron. The Imperial squadron was organized into two wings, and the Alliance fighters systematically focused their firepower on each wing sequentially, achieving their destruction one after the other. The inability of the two wings to effectively reinforce each other stemmed from the Victory-class Star Destroyers' use of the sluggish LF9 ion engines, which hindered their maneuverability.