The ship's most noted action occurred at an unspecified time prior to 3150 when the San Diego, assigned to the Federated-Combine front, unknowingly chanced across Tai-shu Kambei Okamoto, Warlord of the Dieron Prefecture, in the Quentin system. An attempt to evacuate the warlord on an outbound Nekohono'o-class DropShip, the Burradi Mōki, and the frenzied defense alerted the RAF attackers to the importance of the ship. The San Diego used its capital and sub-capital weaponry to cripple the DropShip. The warlord was killed in the subsequent boarding operation, and the Prefecture leadership was crippled.
- Technical Readout: 3150, p. 220 - Castrum - RSS San Diego and her encounter with Warlord Okamoto.