The BTL Y-wing starfighter was built by Koensayr manufacturing. This ship is used as a bomber, it also has 2 laser cannons, and 2 ion cannons. This ship can also hold a R2 unit for co pilot. One of the problems of this ship is that it's slower than other ships. The first known model was the BTL-B, which served during the Clone Wars. The Republic made good use of the model in the beginning of the conflict. The BTL-B had a bubble turret, which swiveled 360 degrees and provided the gunner with a clear view of the surrounding space.
The BTL-S3 was a two-man strike fighter, and was the most common Y-wing configuration. The weapons systems officer typically operated the ion cannon turret when needed. Many Y-wings of this variant were modified with defensive rapid-fire blaster turrets replacing the ion cannon turret and particle cannons instead of the dual laser cannons on the nose.
The BTL-A4 was a one-man version of the S3, which removed the gunner position and locked down the overhead ion cannon.
It was used commonly by pirate, mercenary, and private defense forces, and therefore was also used by the early Rebel Alliance as the primary starfighter for bombing and disabling roles. 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.