Hades-class heavy cruiser

"The UNSC might have had the more advanced ships, and the more comfortable ones, but no cruiser hits as hard as a Vulcan. I believe the Hydra system is a testament to what a single squadron of these ships can do."

- Commodore Mark Hudson

The Vulcan-class heavy cruiser (hull classification symbol: CA) was a heavily-armed model of capital ship that was deployed by the Colonial Military Administration. Built as the hammer that could break down any colonial insurgency, the Vulcan-class formed the backbone of Colonial Navy Squadrons. It remained an awe-inspiring sight for decades after its production stopped.

Named after the Roman god of fire, these starships live up to their name for their ability to dish out an obscene amount of firepower. The Vulcan 's fearsome arsenal of 128 Ares missiles and supporting magnetically-accelerated weapons outgunned almost every other ship at the time, and could conduct planetary bombardment with lethal efficiency. Its armour, although modest by later standards, could withstand impressively-powerful hits to its hull before being breached. This came at a cost to its operational endurance, versatility, and crew comfort. In particular, the sacrifice of adequate crew spaces meant that sailors often lived and worked in overcrowded environments, with no room being any larger than was required.

The Vulcan-class heavy cruiser was the first new Colonial Military starship classification to be commissioned as part of a new modernisation campaign, and quickly became the CMA's premier ship-of-the-line. Its mission saw it responsible for not only for hunting down and usually destroying pirate and rogue warship, but also for show-the-flag operations within the mid-rim colonies. Concessions made within its design saw its maintenance requirements increase the older they became, and the cruiser faced strong criticism from the public over much of its lifespan. Their production life was cut short following the Callisto Incident, although they were an active part of the Insurrection that followed. Any plans to replace them were cut as the CMA's budget was reduced, and by 2525 a number of these heavy cruisers were held up in mothyards.

With the beginning of the Human-Covenant War, all Vulcan-class cruisers, like the rest of the CMA, were placed under UNSC control. Despite being refitted with improved weapons and target systems, they took horrendous losses at the hands of the alien fleets. pulse laser turrets could effortlessly eliminate much of their firepower before they could reach their targets, while their clustered weapons and weak framework often buckled under the stress from their plasma weapons. Although a handful of these ships defected from the UNSC, they served as late as 2536, when the UNSC decommissioned all remaining Vulcan-class heavy cruisers from service.