USS Excalibur (alternate reality)

The USS Excalibur was a flagship operated by the   in the 2250s of the  created by the temporal displacement of the Narada.

History and specifics
The Excalibur, then under the command of Captain Prax, was one of the ships assigned to defend Earth from the Varkolak fleet in 2256. During the crisis, Cadet was assigned to the vessel as relief helm officer. Sulu convinced Prax to listen to 's Priority One order to stand down from engaging the Varkolak fleet, despite the Excalibur being targeted by twelve different Varkolak vessels. 

The Excalibur was part of the Starfleet force that battled starships of the in the 2250s. 

Crew

 * commanding officer
 * Captain Prax (2256)
 * communications officer:
 * Lieutenant Chang (2256)
 * helmsman:
 * Bunch (2256)
 * (2256)
 * tactical officer:
 * Larkin (2256)