R2-A3:R2-A3 was an astromech droid who assisted Rebel Alliance pilot Wedge Antilles. During the Battle of Yavin, R2-A3 and Antilles were forced to retreat after damage was dealt to their X-Wing's engine.
R5-K6:R5-K6 was the astromech droid alongside Garven Dreis, the leader of Red Squadron, during the Battle of Yavin, R5-K6 and Dreis were shot down while attempting to destroy the Death Star.
R2-F2:R2-F2 was an astromech droid for Biggs Darklighter, a Rebel Alliance starfighter pilot. Both R2-F2 and Darklighter perished in the assault on the Death Star.