Battle of Theta Kalyb

The Battle of Theta Kalyb was a conflict between Tholian shock troops, the Chakuun, and a task force of five Federation Starfleet vessels in orbit of planet Theta Kalyb in 2254. 

Starfleet starships

 * USS Enterprise (NCC-1701) - damaged
 * USS Nelson (2250s) - damaged (senior staff killed)
 * USS Achilles (2250s) - destroyed (53 crew beamed to safety)
 * USS Brazzaville - destroyed
 * USS Providence (2250s) (Nelson-class) - destroyed