Ison Corridor ambush The Galactic Empire launched the Ison Corridor ambush against Rebel forces in the Ison Corridor immediately after the fall of the Yavin 4 base . Prelude . After the evacuation of Alliance High Command from the Rebel base at Yavin 4 in 0 . 5 ABY , two convoys were directed to rendezvous in the Ison Corridor . Upon arrival , though , the first convoy was wiped out by an " Imperial " - class Star Destroyer that was previously hidden in a nebula , although it came at the cost of said Star Destroyer . The battle . The second convoy , led by the frigate " Redemption " , and consisting of six GR - 75 medium transports escorted by three T - 65B X - wing starfighters , arrived to discover the area littered with ruined ship parts . The frigate ' s Captain realized they had to move through the debris field before escaping . Suddenly , squadrons of TIE fighters ambushed the convoy from three different directions . At the start of the battle , Red Leader Luke Skywalker noticed an object within some space debris . Temporarily leaving the battle , he managed to find an advanced proton torpedo tech upgrade before returning to defend the transports . Because of the agility of the TIE Interceptors , the Rebels had to switch to a faster craft than their X - wings , which incited Red Squadron ' s first use of A - wings in battle . Skywalker docked with the frigate and took control of an A - wing . Then , once the Interceptors were destroyed , the convoy had to move through a nebula before they could jump to hyperspace and escape . The convoy moved into the nebula , and more TIE Fighters and TIE Interceptors attacked them through the dim lights of the nebula . The Rebel pilots managed to destroy all nearby TIE fighter squadrons , although they needed to use their targeting computers to do so under Luke ' s command beforehand . Red Squadron was able to protect all the transports , although the frigate " Redemption " did suffer some moderate damage , but nevertheless the convoy reached Echo Base on Hoth . Aftermath . After the convoy arrived , the Rebels began the long process of creating Echo Base , which would later be the site of a key battle in the Galactic Civil War . After the death of Narra and the destruction of Renegade Flight , Skywalker was promoted to Commander and put in charge of the squadron . Behind the scenes . The ambush appeared in the video game " . " Picking up the upgrade in the mission will fulfill the bonus objective , and the player has the option of switching to the A - wing mid - mission . The convoy may take up to five casualties before failing the mission , but this article assumes 100 % completion . The game ' s campaign was included in " " , although the co - op version features nine transports to defend . This article follows the original portrayal . The objective to defend at least one transport remained . Dialogue from Wedge Antilles revealed that the A - Wings were actually first deployed during this battle , leaving some contradictions regarding A - wings participating in battles taking place before the Ison Corridor ambush , and eventually led to a retcon where the ships before the battle were labeled as the R - 22 Spearheads , the predecessor to the A - wing .