Centauri Republic Primus Class Battlecruiser

Only a fraction smaller than the Octurion, the Primus is the normal flagship of the Centauri navy. They are less expensive and far more commonly seen in the fleet. The Primus is a testament to the might and power the Centauri once wielded in the galaxy. Among the strongest of the frontline vessels designed by the younger races, Primus battle cruisers mount a large number of weapons, permitting them to engage almost any enemy at varying ranges and angles with a good chance of a victorious outcome. Between powerful battle lasers and accurate twin arrays, few ships of lesser stature can hope to survive long against a baseline Primus. It is said to lack the powerful secondary armament usually found in ships of this size, which often leads enemy captains trying to close range when engaging but the powerful battle lasers mounted on the Primus are more than capable of crippling an enemy as he maneuvers and accelerates to do so.

The Primus was the hull of choice when it came to construct the Emperors’ personal cruisers and it has since become one of the most recognizable ships in the Republic’s fleet with several variants ensuring it will remain in service for decades more to come. Unimaginative in naming the first two types of variants – the Secundus and Tertius – the Primus hull had been used to create a very capable assault transport/escort version in the first, and a ship-hunting plasma variant in the latter. These are both tried and true variants that may give up some of the versatility of the Primus, but sit firmly in the niche they were created for.

Primus Battlecruiser
Secundus Battlecruiser
Tertius Battlecruiser

Source
The Babylon 5 Project: Primus class battlecruiser
Babylon 5: Ships of the Galaxy (pages 53-55)
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