In 2366, the Pi, crewed by Patahk and Centurion Bochra, was carrying out a covert mission when it crash landed on the planet Galorndon Core, inside Federation space. The Pi was destroyed with an ultritium explosive after the crash to prevent its capture by Starfleet. Both Romulan crew members were eventually retrieved by the USS Enterprise-D. Patahk died from his injuries, while Bochra was returned to the Romulans. (TNG: "The Enemy")
Background information Edit
The mission of the Pi was not revealed in the episode.
Pi was a Greek letter, although it was unknown if there was any relation. In this usage, though, the "relationship" is most likely simply homophonic.
The Starships RPG sourcebook gives its registry as IRC-13301.
The name Pi was later used for a Romulan Griffin-class ship instead of the scout ship type in the game Star Trek: Armada.