A plasma torpedo is a weapon consisting of a torpedo armed with a charge of plasma, most often used as a starship mounted weapon.
Many Romulan, Gorn and Klingon starships are equipped with types of this plasma weapon. The Cardassians use them in their orbital weapon platforms. (TOS episode: "Balance of Terror", DS9 episodes: "Tears of the Prophets", "Image in the Sand", "Shadows and Symbols") [citation needed]
The Wellington-class Federation light cruiser starship mounted the "long lance" variant plasma torpedo, which was designed to disrupt sensors and computers at long distances. (FASA RPG module: Star Trek: The Next Generation Officer's Manual)
Starfleet Command series
The Bismark subclass of the Excelsior-class carried F-type torpedoes.
- In the TOS video game: Starfleet Command, Excelsior class starships were never referred to by name, despite having Excelsior hulls.
In that same game, plasma torpedo launchers were ranked by the sizes of the largest casings these launchers could fire. Type-R plasma torpedo launchers were the largest and were first fielded by the Romulans. Type-S casings were somewhat smaller and had less range than Type-R casings. Type-G torpedoes were first fielded by the Gorns. Finally, Type-F were the smallest casings available.