In 2360, Captain Picard of the USS Portia ordered a class-8 probe dispatched to act as a log buoy, in case the ship's current, secret mission failed. (TLE novel: The Buried Age) In 2365, Federation special emissary K'Ehleyr travelled from Starbase 153 to the USS Enterprise-D on an urgent mission in a heavily modified class-8 probe because no starship was available at the time. (TNG episode: "The Emissary")