The Defense of the Liberty was a battle fought between the Galactic Empire and the Alliance to Restore the Republic that took place in 3 ABY. Experimental TIEs attacked the Liberty, but it was successfully defended by the ship's fighters.
Some time before the Defense of the Liberty occurred, the Mon Calamari Star Cruiser Liberty was assigned by the Rebel Alliance to investigate unusual Imperial activities in the Vilonis Sector. Civilian convoys were being attacked by unknown fighters that were clearly Imperial in origin, but of radical designs. Pilots assigned to the Liberty soon found out that the unusual starfighters were the latest installments in the TIE series, the TIE Experimentals. Seeing the threat they posed to civilian and Rebel shipping, the Liberty launched a campaign to shut down this new Imperial starfighter project. Prior to the aforementioned Imperial ambush, the Rebel Alliance raided the Bretie Facility, a space station where vital data on the new starfighters was being contained, and where fighters were being produced. The Rebels got the data and the station was destroyed, and immediately began to research the nature of the new fighters. However, they had no idea that the Imperial authorities were on to them.
Within hours after the Bretie Facility had been destroyed, the Imperials were able to track down the Rebel raiding force to the Liberty, and launched an all-out assault on the cruiser. The ambush force was made up entirely of Experimental TIE fighters of all types, including the newly introduced TIE Experimental M4s. They were remote-controlled by pilots on board Beta-class ETR-3 escort transports from Suluk Group. The enemy fighters fired upon the Liberty relentlessly, so the Rebels launched dozens of starfighters of various classes to engage the enemy. The Rebels fought tenaciously despite the losses they were sustaining, and managed to destroy wave after wave of fighters. At least three waves of fighters attacked the Liberty, and they all came with TIE Experimental M4s, which made kamikaze attacks on the Liberty, as they were designed strictly for kamikazes on enemy starships. The Rebels destroyed most of these craft, but the Liberty sustained significant hull damage from the fighters that broke through. Despite the enormous attack, the Rebels ultimately wiped out their pursuers, saving the Liberty and the mission to end the TIE Experimental Project.
Despite the damage and losses sustained by the Liberty and her crew, they were able to continue their mission and discovered that the TIE Experimental Project was being carried out on the research station Obsidian by a man named Director Lenzer. The Rebels found the location of this base and succeeded in destroying it and all existing TIE Experimentals. After this battle, the TIE Experimental Project was presumed to have ended.
- Star Wars: X-Wing Alliance (First appearance)