Battle of Derra IV The Battle of Derra IV was an engagement between the Galactic Empire and a Rebel Alliance convoy near the planet Derra IV . Build up . Grand Admiral Thrawn , while working to undermine the influence of Black Sun on Corellia , discovered that the weapon - smuggling freighter " Hopskip " was bound for Derra IV . This information , combined with other evidence gathered by Imperial Intelligence , demonstrated that a Rebel supply convoy was intending to depart from that planet to the new Rebel base . Darth Vader and Thrawn worked together to develop the plan that would send the 181st Imperial Fighter Group to eliminate them . Vader presented this plan to the pilots , though one of them Soontir Fel recognized that the plan was the brainchild of the quiet alien Admiral . This act left Fel irritated , disgusted at the hypocrisy of an alien being relied upon as the savior of the Empire , when Human superiority was a major premise used to justify Imperial policies . Ironically , Thrawn would receive no credit for his role in the battle , and Fel would later serve under Thrawn ' s fellow Chiss in the Empire of the Hand . Battle . The convoy soon left Derra IV , but before it could enter hyperspace , a Star Destroyer appeared , and the TIE fighters of the 181st pounced on the unsuspecting Rebel ships . Despite the best efforts of Renegade Flight to defend the convoy , it was utterly destroyed . Soon afterward , Renegade Flight , which was part of Red Squadron , met its end as well , with Commander Narra dying at the hands of Fel himself . The battle , although relatively insignificant and rather one sided , was a major victory for the Empire . The three major players in the 181st ( Turr Phennir , Evir Derricote and Soontir Fel ) were promoted in a major ceremony on Coruscant presided over by Emperor Palpatine himself . Phennir was given command of the 181st ' s second squadron and promoted to Commander for destroying four Rebel transports ; Derricote was placed in charge of the Imperial facility on Borleias and promoted to General ; and Fel was promoted to Colonel , given command of the 181st , and granted an estate on his native Corellia , to which he moved his family shortly thereafter . Though the plan was put together by Thrawn , he received no credit for the battle . As he was already a Grand Admiral at the time , there was perhaps no further honor he could receive . Some suggested that Ysanne Isard had the Emperor afterwards reassign Thrawn to the Unknown Regions to avoid the embarrassment of an alien ' s strategic achievement . Moreover , the battle left the Rebel defenses at Echo Base on Hoth badly understaffed , with no opportunity for resupply and with only the forces of Rogue Flight to defend them . Following the death of Commander Narra , Luke Skywalker of Rogue Flight was promoted to Commander and took control of Red Squadron , which he soon after molded into Rogue Squadron . A small number of the pilots from Renegade Flight survived , but were wiped out in the Ison Corridor . Aftermath . This battle would later be made into a simulation for New Republic pilots to attempt . While kept in captivity on Coruscant in 40 ABY , Wedge Antilles tried this simulation with no luck .