From the Super Mario Wiki, the Mario encyclopedia
Stormtroopa Starfighters are small, one-seat spacecrafts that were created for outer space combat. These vehicles are the starfighters used by Darth Koopa's Stormtroopas, and seem to mirror TIE fighters from the Star Wars films. Oddly enough, they appear to resemble cooked turkeys. Stormtroopa Starfighters only appeared in The Super Mario Bros. Super Show! episode "Star Koopa".
When Mario, Luigi, Princess Toadstool and Toad attempt to breach Koop Star in Mushroom Starfighters, Darth Koopa orders his Stormtroopas to defend his spacecraft from his foes. As much as the Stormtroopas try, they are unsuccessful in taking down Mario's group, and many Stormtroopa Starfighters are destroyed. Several more Stormtroopa Starfighters go after Mario as he flies through a trench indentation along the surface of Koop Star, but they either crash into a protruding wall or are hit by one of Toad's attacks.
All of the Stormtroopa Starfighters appear to have been destroyed once Koop Star blows up, which suggests that these starfighters may no longer exist.