In late 2155, the Yorktown was under the command of Captain Ketai Shosetsu, and engaged in battle with Romulan ships near the planet Valakis. She suffered heavy damage and casualties. On November 27, 2155, the Yorktown left the Proxima Maintenance Yards after undergoing repair&refit. During the overhaul a number of new crewmembers were assigned to the ship including Ensign Travis Mayweather. After the battle, the Yorktown underwent repairs at the Zeta 2 Reticuli repair and shore-leave facility, where Mayweather left the crew. (ENT novel: Beneath the Raptor's Wing)