BTL-A4 Y-wing starfighter

The Koensayr BTL-A4 Y-wing starfighter was crewed by a single pilot. The 16-meter-long attack starfighter had an ArMek SW-4 ion cannon turret which was preset to one of four arcs and was typically locked forward, although some pilots chose to lock it facing aft for extra cover. Easily modifiable, the variant boasted much greater endurance (as much as three times greater) over its earlier predecessor, but was penalized with less powerful deflector shields and loss of accuracy in the ion cannons. The loss of shield power provided a boost in engine power, but the combination proved insufficient and the Y-wing variant developed a poor reputation among its pilots, and the starfighter was said to move like a "sleepy Hutt." Although slow for ship-to-ship combat, it was still capable of engaging other craft, and the Y-wing was excellent when used for planetary bombing runs.

The wedge-shaped cockpit and Guidenhauser ejection system was placed on the front of the craft, with the central spar containing the Novaldex power generator extending behind it. Thiodyne 03-R cryogenic power cells and ionization reactor supplemented the Novaldex generator. Two 2 Koensayr R200 ion jet engines, rated at 250 KTU and capable of 100 MGLT were attached to either side of the spar. The engines had exhaust nacelles and support pylons, and the Fabritech ANx-y long-range sensor array with PA-9r long range phased tachyon detection array and PG-7u short range primary threat analysis grid were placed in protective composite domes on the front of the nacelles. The craft also had a Fabritech ANc 2.7 tracking computer with SI 5g7 "Quickscan" vector imaging system, and a Subpro NH-7 flight control avionics package. Y-wings also carried supplies for one week in 110 kilograms of weight. The R300-H Class 1 hyperdrive was at the rear of the spar. The Chempat shield generator was also located on the spar. Three repulsorlift engines aided in maneuvering. The weapons were located in the cockpit: two Taim & Bak IX4 or KX5 laser cannons along with two Arakyd Industries Flex Tube proton torpedo launchers each with a magazine of four torpedoes. The Y-wing could also carry 20 proton bombs. The factory-fresh starfighters featured armor-plating around the central spar and the engines. Technicians eventually kept the panels removed to facilitate repairs. Squadron markings were placed on the cockpit and the forward tips of the engine nacelles.

The BTL-A4 Y-wing attack starfighter traces its lineage back to the Clone Wars and the BTL-B Y-wing starfighter used by the Galactic Republic. After the war, the starfighter was put into service by Planetary Security Forces. As the resource-strapped Rebel Alliance started to grow its resistance against the Galactic Empire, Y-wings started to be used more often, becoming the Rebel's primary starfighter. The starfighters were brought into use by defecting Planetary Security Forces pilots, liberated from Imperial storehouses, or outright bought from pirates or unscrupulous governors.

Y-wings were used since the earliest battles of the Galactic Civil War. A squadron joined in the assault on the major Imperial cloning centers on Kamino in 1 BBY. During the battle, Starkiller rode on the outside of one piloted by the future ace Wedge Antilles for a short time.

As the BTL-S3 became the primary Y-wing variant of the Rebel forces, the A4 was still kept in many units as a supplementary craft. Despite the existence of the BTL-S3, the BTL-A4 variant of the Y-wing was favored by Red and Gold Squadrons, and served with distinction in many major battles. They were the starfighter intended to destroy the first Death Star during the Battle of Yavin. Flown by Gold Squadron, a trio of Y-wings were the first to launch a run into the trench to their target, an exhaust port leading to the main reactor, although the pilots were all shot down. Eventually, Luke Skywalker, in an X-wing, succeeded in hitting the target. After the Battle of Yavin, the starfighters were assigned to less dangerous missions.

Members of Rogue Squadron flew the BTL-A4 on strikes against Imperial targets, including the Kile II spaceport assault and the destruction of the capacitor on Sullust. After the Battle of Hoth and between 3 ABY and 4 ABY, Rogue Squadron used Y-wings on a mission to The Maw, and Antilles used one to bomb the Imperial ground forces and the hull of the crashed Imperial-class Star Destroyer Motivator that was holding the CR90 corvette Razor. Antilles also flew one during a battle at Dubrillion to destroy a superlaser threatening a Rebel fleet.

During that same time period, Rebel pilot Ace Azzameen also flew the A4 Y-wing on missions, including a mission along with the Bothans Blue Squadron. The Bothans, sympathetic to the Rebellion and flying S3 Y-wings, participated in the capture of the Imperial freighter Suprosa during the raid to capture a supercomputer containing the plans to the second Death Star. More Y-wings were destroyed than any other Rebellion starfighter. The Y-wing was supplanted as the Rebellion, and later New Republic's, assault starfighter by the B-wing and K-wing starfighters.

The Y-wing is based off concept art made by Ralph McQuarrie. The starfighters seen in the first Star Wars film, A New Hope, were models produced by Industrial Light & Magic and filmed against bluescreens.

There is a discrepancy between two sources concerning the internal size of the main laser cannons. Y-Wing blueprints created during production of Star Wars: Episode IV show the internal laser cannons ending before the pilot's feet, whereas in Star Wars: Incredible Cross-Sections they continue throughout the entire cockpit.

Star Wars: Rogue Squadron: The Official Nintendo Player's Guide erroneously labels the A4 as the S3 version, as does Star Wars: Rogue Squadron II: Rogue Leader: The Official Nintendo Player's Guide.