An Excelsior-class Federation starship on which William Riker served as a lieutenant, leading the 2361 evacuation of Nervala IV that unknowingly created his transporter duplicate.
The second USS Potemkin known to the archive was an Excelsior-class ship in service throughout the 2360s. William Riker served aboard as a lieutenant before his promotion and transfer to the Hood.
In Second Chances it is revealed that during the evacuation of the research station on Nervala IV in 2361, the Potemkin's transporter chief used a second confinement beam to pull Riker through the planet's distortion field. One beam was reflected back, leaving an identical Riker stranded for eight years.
The ship is mentioned several other times. In Legacy it is named as the last Federation ship to visit Turkana IV, and in Ethics it brings the neurospecialist Doctor Toby Russell to the Enterprise-D.