Stuka Ju-87
The Junkers Ju 87 (or more commonly known as the Stuka dive-bomber, an anglicized abbreviation for "Sturzkampfflugzeug" or "Sturzkampfbomber") is an airplane used on Earth, by Germany, during World War II.
The plane was commonly used by German Luftwaffe in bombing campaigns on Poland, France, the Soviet Union, Greece, Yugoslavia, Netherlands, Belgium and England. They fired 7.92mm rounds and were equipped with sirens located on the wheel covers to frighten the enemy on the ground during dives from high altitudes.
When Enterprise was trapped in an alternate timeline in 1944, the ship entered Earth's atmosphere to destroy a temporal conduit that the Na'kuhl were constructing. Their leader, Vosk, dispatched a squadron of Stukas refitted with plasma cannons to destroy the ship. (ENT: "Storm Front, Part II")
- One would wonder why the Stuka was used against the Enterprise as Stuka's were not fighters and were rarely used for air-to-air combat. It is possible that they had originally been modified to carry plasma cannons for ground attack (many real world Stukas carried large anti-tank cannons for the same role), and that they were either the closest aircraft so armed, or the only ones carrying plasma cannons.