From the Super Mario Wiki
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. 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 attempted to breach Koop Star in Mushroom Starfighters, Darth Koopa ordered his Stormtroopas to defend his spacecraft from his foes. As much as the Stormtroopas tried, they were unsuccessful in taking down Mario's group, and many Stormtroopa Starfighters were destroyed. Several more Stormtroopa Starfighters went after Mario as he flew through a trench indentation along the surface of Koop Star, but they either crashed into a protruding wall or were hit by one of Toad's attacks.
All of the Stormtroopa Starfighters appeared to have been destroyed once Koop Star blew up, which suggests that these starfighters may no longer exist.