• Class:VIII
• Year:2175
• Ship Source:The Starfleet Museum
• Ship Datasheet:Coming Soon

The introduction of matter/anti-matter power plants into the majority of new Earth Alliance ship designs from 2158 onwards meant that in virtually every confrontation the Romulans were outmatched.

The Romulan fleet had invested heavily into developing artificial quantum singularities as a power source, to try to counter these new power plants. This meant however that they neglected research into the far simpler matter/anti-matter source, and only put limited funds into improving their fusion reactor systems, meaning that no significant improvements occurred in this field until very late in the war.

The U-25A (codenamed ‘Clavicle’), which entered service in 2159, benefited from the new fusion reactor research, and was the first Romulan cruiser that could match most Earth vessels in a confrontation since the advent of matter/anti-matter power in the Earth Alliance ships. The U-25A returned to the flatter shape of pre-war ships, as the Romulan fleet acknowledged that the increase in production time and cost was far outweighed by the improved warp dynamics it offered. The combination of this improved shape and the new power plant gave a top speed in excess of warp 4.2.

The use of Fusion, which relied on ample supplies of deuterium fuel, limited the range, but as with the U-24, the Romulan fleet was now fighting within range of its home bases, so this was no longer a priority. Firepower was still a priority; the U-25A carried an impressive mixed and balanced arsenal. When used cleverly the U-25A was a good as most opposition it would face. In a chase, the weaknesses of the limited range would soon show, but when used to ambush enemy forces the class was devastating. Even in an ambush situation, the U-25A had to destroy its target before reinforcements arrived, as full speed would soon exhaust the fuel supply if pursued.

The other factor about the U-25A that weakened it was the power plant itself. The technical achievement in almost doubling the power output was impressive, but the penalty was that if pushed too hard the reactor could easily overload. Reactor explosion, rather than enemy fire, accounted for half of all U-25A losses. 25 U-25A were built in total, of which 15 saw Romulan war service, and of these 11 were destroyed. The limited numbers produced, and the lateness of the introduction into service meant that the U-25 had only limited influence on the outcome of the war. It did, however, reassert the Romulan style of ship design that later became synonymous with all their vessels.

Post-war improved U-25B and C variants saw service, some of these ships survived in the fleet until 2200. The U-25B (2165) introduced improved shields (a major lesson learnt from the war) and an improved plasma cannon. The final version, U-25C changed the balance of the design by mounting more, less powerful starbombs, to compensate for the fitting of a second plasma cannon, as well as enhanced beam weapons.

• Class:XI
• Year:2159
• Ship Source:The Starfleet Museum
• Ship Datasheet:Download PDF

The U-24 (Codename ‘Chowder’) was a Strike Cruiser, for use as part of the defensive strategy. Compared to the U-22 Class the U-24 was a far lighter and more manoeuvrable design. This performance improved also included an increase in maximum speed to Warp 3.2.

The U-24 gradually replaced the U-22 in production as the Romulans shifted from offence to defence; operating close to bases meant that Cruisers no longer required the amount of fuel that the U-22 had carried to extend its reach.

In terms of armament, the U-24 did still pack an appreciable punch, again carrying star bomb anti ship missiles and defensive cluster missiles. The class also carried a nose mounted plasma cannon, although this was of lower power than that of the U-22. Frequently, U-24s were employed in an anti capital ship role, their speed and manoeuvrability giving an edge over the lumbering Earth Battle Cruisers and Carriers. They proved to be vulnerable themselves, as the lighter structure that gave the U-24s their speed made them vulnerable to attack from nimble Minotaur class fighters and Powhatan class Cruisers.

U-24s managed to destroy 5 Yorktown class carriers, and 19 other capital ships of various types, but that was at enormous cost, of the 112 U-24s deployed during the war, ships destroyed or listed as missing totalled 82.

Three distinct variants of the U-24 exist. The most common was the U-24A, which entered service in 2258. This mounted a mix of defensive and offensive missiles as well as the Plasma Cannon, 81 of the ships built during the war were of this type. Production continued post-war and a further 38 ships were built of this mark. The second variant (again in service from 2158) was the U-24B, which carried only star bomb anti ship missiles. The Star bomb variant carried by this mark was the lightest (and least powerful) produced by the Romulans, the RM-SB4. It could however carry ten of the weapons, and it retained its plasma cannon as a back up. Some 30 of the completed ships were of this model.

The U-24C, of which saw only a single prototype built, adopted an all or nothing approach. This variant dispensed with all weapons except for the star bombs. As a result, it could carry sixteen of the light RM-SB4s for use against high value targets. The variant was also fitted with a further star bomb in its nose, for use as a last resort weapon in ramming actions.  Intended for use in the defence of Romulus, this variant began testing in mid 2159.  Luckily, for both sides, the war ended before this model saw action. Testing indicated that the ship was woefully underpowered, and could only fire a useful salvo if not manoeuvring or not powering the already inadequate defensive screens, additionally it lost the manoeuvrability that made the U-24A so devastating.

The U-24 was a departure from the larger designs that preceded it. Many things including the changing nature of the conflict and the need for quick to produce ships caused this change. However, the striking power of the U-24 was almost equal to that of many earlier and far larger cruisers; both the Romulan and Federation fleets followed this trend post war, meaning the leviathans that saw action in the Romulan War soon faded into history

The U-22 (codenamed ‘Cabbage’ by the UESN) entered service in 2155, and was one of the most commonly encountered Romulan Cruisers during the war. The design was created to allow fleet advances across interstellar distance. They were equipped with a formidable arsenal of cluster missiles and Star Bombs, and also mounted the most powerful plasma weapon yet produced, and this could be carried for distances further than any other Romulan Cruiser save for the U-13A.

However, this massive capability came at a price; the amount of deuterium fuel required by the fusion reactors to give the required range meant that the ships weighed an estimated 500,000mt. Plans to use the twin-engine system developed for the U-20 were abandoned due to delays in that program, and a modified version of the long serving RFTL-3 was adopted in a triple nacelle arrangement. The massive mass of this class badly affected its manoeuvrability and performance at warp (2.5 maximum speeds).

Early in the War the U-22 was used to great effect, the firepower overwhelming many Earth Alliance ships, and the sheer size of the vessel meant that the damage inflicted on the U-22 was easily absorbed. Later in the war as newer designs entered service with Earth and its allies, the slow ponderous U-22s became easy prey.

The vulnerability of the U-22 was demonstrated very clearly at the battle of Hell’s Gate on 21-23 October 2157. This battle saw the Earth Alliance forces crush a massive Romulan Invasion attempt. 27 U-22 Cruisers were committed to this battle, and not even one survived, it is estimated that the Romulan loss of life in this battle was in excess of 30,000 crew and troops.

The cruiser was designated as the U-22A, at the start of the war some 75 U-22As were in service, and these were joint by a further 30 built during the war. Numerous variants of the U-22 also served during the war, despite the change in roles they were all classified as part of the same series and retained the U-22 designation. The U-22B (Codename ‘Tonsil’) was a tanker built to support long-range U-22A operations, production totalled 15. Armament was reduced to just the defensive cluster missiles.

U-22C (Codename ‘Rodent’) was used as a subspace sensor/communications ship, often deployed on long intelligence gathering sorties. This class retained the plasma cannon and cluster missile, but dispensed with the star bombs to allow for the fitment of advanced sensor equipment. Only 10 of these specialist intelligence ships were built. U-22D (Codename ‘Syrup’) was a specialist troop transport/assault ship; it could carry some 2000 troops. The weapons fit dispensed with plasma weapon, but retained a full missile arsenal for self-defence and planetary assault. The U-22D was the second most common variant, with some 35 seeing service.

The U-22 suffered from the compromise made in its design, Romulan fusion engine technology meant that the only way to gain a long range was to carry massive amounts of deuterium fuel, this fuel meant that the ship’s power efficiency and speed would always be inferior to ships built for speed and manoeuvrability, especially when those ships also used matter/antimatter propulsion.