The Doomsday Express is ?.
This airplane is the first of Dark Kat's vehicles seen in his debut episode The Wrath of Dark Kat. With it, he was able to break into and steal nuclear fuel rods from the Megakat Nuclear Power Plant. Commander Feral had managed to sneak aboard the Doomsday Express, and was captured by Dark Kat later on and brought to Dark Kat's volcano lair. After being discovered by the SWAT Kats, Dark Kat used this plane to escape his lair and attempt to drop his Doomsday Device in the center of Megakat City, right on Enforcer Headquarters. The bomb was dropped but disarmed by Razor, and the Doomsday Express was finally shot down by T-Bone