Orion-class assault carrier (EXverse)

The Orion-class assault carrier is a heavy tonnage carrier capable of maintain control over a planet's orbit. Built to be the UNSC's next generation flagship, it became the symbol of the UNSC's military might.
Built by Sinoviet Heavy Machinery under the oversight of naval architect Kotomi Imanishi, the Orion-class was conceived as a class capable of maintaining a planet's orbit control and, at the same time supporting ground troops logistically; these tasks were achieved by implementing the same miniaturized and reconfigurable automated factories and chemical processors found on colony vessels, which allowed a carrier to produce spare parts, fuel and even complete vehicles without outside assistance.
During the Insurrection Orion carriers successfully led lengthy campaigns, but the glory came with Operation: TREBUCHET. During this operation, Orions' Flight II vessels assembled an unstoppable team with newly-acquired supercarriers, blowing to pieces every single rebel fleet.
Insurrection's fanfare, however, ruthlessly ended when the Covenant attacked Harvest, leading to the Great War. Having a modest armor and a light armament - except the two heavy MACs - Orions underwent a major refitting process, as practically all other UNSC ships. Despite this, Orions fell one after the other as they were used to buy time for civilians and troopers to be evacuated, efforts that cost many carriers. By the time the Covenant started to onslaught the Inner Colonies, UNSC High Command decided to organized long-range battle groups in order to disrupt Covenant supply lines and staging areas, and decided to put Orions at their core thanks to their internal factories. But the HIGHCOM's plan hadn't much success and at least seven were lost.
Only six carriers survived the war, but the Navy decided not to upgrade them. Instead, they chose to use the remaining Orion carriers to help glassed worlds back to life, as their internal factories would be helpful to accomplished the task, while its military roles would have been filled by its replacement, the , which however wasn't still commissioned by the time Cortana subjugated Earth.
== History ==
=== A new type of carrier ===
In the middle of the 25th century, tensions between Earth and her Outer Colonies began to arise, so the CMA started to evaluate the situation. The colonial authority found that, in case of a prolonged campaign, it would have had lots of issues, because many Outer Colonies were far from naval depots; besides, relationship between its navy and marines weren't close enough, in fact the colonial navy hadn't much carriers to conduct joint operations with. Until then, colonial marines had relied on civilian vessels, capable to enter in the atmosphere or large enough to carrying them and their equipment, otherwise they used scattered spaceports, from which they landed on planets' surface; but in the latter case the problem remained: differently from highly developed Inner Colonies, many of the Outer Colonies were so poorly developed - except a handful like Meridian, which meant that they had only one spaceport.
So the CMA had a big issue, even if prolonged campaign would have never happened until the end of the 25th century, an issue that CMA decided to resolve by funding massive ships which could have sustained an entire Marine Expeditionary Force for months, maybe a full year, enough because a campaign could have been successful; obviously, these ships would have more purposes than only carrying and refueling ground troops: seeing its theoretical size - at least two hundred millions metric tons, for a length no less than three kilometers, something never made before - it should have been also capable of dominating a planet's orbit by both its starfighter wings and its own weapon systems.
Someone noted that big ships meant also big expenses, other than marines wouldn't have a small, more agile and faster carrier but only a big, slow and not capable to enter inside a planet's atmosphere one. However, with tensions rising more than ever after the 2490, the colonial authority started to have fear of not be able to handle the situation. So, after decades of theories, in the 2490 the CMA finally commissioned a massive line of ships, the , which could sustained entire campaigns for months thanks to a large internal concave hangar bay. These masterpieces of engineering, however, were utilized a few times, as they were conceived in times where CMA's budget was still high; but by the start of the Insurrection in 2494 the situation was already changed: UNSC wanted to usurp the CMA even in Outer Colonies, and the UEG weren't much convinced to allocate to CMA too much resources, especially when some rumors about rebel infiltrators among CMA's ranks came out. The situation never got better, since in 2497 evidences of rebels infiltrated in the CMA were found and confirmed.
On the other side, UNSC decided to face the problem in a different way well before the CMA commissioned its big vessels: in 2468 it chose to undertaking a more friendly-budget approach, by launching a RFI open to all shipyards which asked a carrier capable of sustained the lengthy campaigns that UNSC was about to start; no massive ships such as future Punics, but at least as large as their half.
All shipyards company proposed an airframe heavily based on Phoenix-class support vessels, of which this new carrier was seen as a natural descendant, thanks to a large internal space; however, these ships hadn't what the Navy was looking for, in other words something that could be not only support ground troops, in which Phoenix ships already worked greatly, but also maintaining aerospace control: converted colony ships weren't powerful enough nor they had a bridge large enough to accomplish these tasks. Then, airframes proposed by all shipyards were powerful enough to fight for aerospace control, however internal factories were removed in order to save money and to enlarge hangar bays, therefore expanding the complement that a carrier could carried, even if removing factories meant that the ground troops' resources would be limited.
Sinoviet Heavy Machinery, on the other side, appointed Kotomi Imanishi to developed such carrier. She took a different path: maintaining internal factories and chemical processors, and installing them on a completely new superstructure. The creation of a new airframe was considered by Imanishi as necessary, since Phoenix-class airframe had many drawbacks which restricted the potential number of weapon systems capable to be fitted onto the hull. Besides, she put a large bridge capable of holding not only the ship's command staff, but also an admiral and his/her staff.
Imanishi's design gained approvals by many officers; also the large bridge was appreciated, allowing flag officers to command fleet by there, so using what would become the Orion-class as flagship. So, on December 13, 2472, Sinoviet was awarded seventy ships, even more than the number that UNSC needed at the time.
=== The Insurrection arise ===
Many criticized the number of ships ordered arguing that no real threat existed and that such large ships would have no reason in order to justify the expense. As the threat of the Insurrection was far away at the time, UNSC Navy, at the suggestion of relevant politicians, cut orders down to forty vessels, saving money for other projects. However many flag officers were disappointed by the UNSC Naval Command's decision, worrying about the situation that was rising in Outer Colonies.
Nonetheless, after the Insurrection broke out, the number of new technologies and materials available give the Navy the opportunity to ask a new batch of Orions, a way to increase their number without questions; but, in the meantime, a major flaw had been found: the inability to accept the newly-developed Magnetic Acceleration Cannon. The superstructure indeed couldn't tolerate the MAC's recoil, which warped the hull a bit after every shot.
So, Imanishi and Sinoviet were forced to review the model and to reinforce the hull, granting that not only one MAC could be fitted, but also two of them. However modifying the hull required new ships to be built: due to this the Navy's command decided to scrapped all Flight I's vessels and using their materials to lowering expenses on Flight II's ones. On one side, Sinoviet approved the idea, enjoying the fact that, in this way, it could build ships cheaper; on the other, the Navy didn't have no interest in keeping ships that couldn't have a MAC - a weapon considered standard by then.
On February 17th, 2502, the first Flight II's ship, known as Orion - the same as the first Flight I's ship - was commissioned.
=== The consecration at Eridanus ===
After the start of the Insurrection, these carriers finally found a purpose, but their consecration happened when Operation: TREBUCHET begun: starting with the campaign in and around the Eridanus system, they became famous alongside the much larger Punic-class supercarrier, in the meantime ceded to UNSC by CMA, forming with the latter a valuable duo, crushing rebellion throughout the human space without pity. However upkeep costs where so high that UEG was forced to increase the UNSC's budget twice in five years, but results were incredible, to the point that no one, in the Inner Colonies or on Earth, criticized these massive expenses.
Anyway, a fleet led by an Orion carrier, during Insurrection, was seen a symbol of the UNSC's military power, such that aerospace control of entire systems was never been threatened by rebel fleets, differently from the planet's ground where rebels were able sometimes to gain control.
=== Human-Covenant War ===
In the first years of the war Vice Admiral Cole made extensive use of Orion carriers, in fact many were lost; Cole frequently engaged Covenant in prolonged campaign, and the automated factories were perfect for supplying his fleet alongside without need to go back to depots.
Orions, as many old ships, were retrofitted to modern standards; but thanks to the new hull developed twenty years before, this time assault carriers could be simply refitted without built them from scratch. The new Titanium-A2 armor, new sensors, new engines, new MACs and a new organization for carriers' internal bays. Regarding MACs, a new Mark IV, Heavy Coil, version was fitted, which granted a 10% output higher than the previous version and a lower charging time; these guns were capable to pierce through a quite easily, and severly damage a with a single slug. Two more Ramparts were also fitted.
Imanishi, besides, didn't want to change the Orion-class' role, but she managed to modified it without change much of the ship. Since an invasion of the Covenant space was, by the dawn of the war, highly improbable, she understood that Orions could have a new role as escort ship for large and small fleet alike; so he reorganized the entire carrier's hangar bay by removing much of the ground troops' quarters and using the empty space left with additional fighters, and most of remaining quarters were assigned to additional flight crew - necessary seeing the increment of starfighters carried. Even SOEIV drop pods were removed, so Naval Command decided not to host ODSTs aboard Orions, a decision that didn't like to many, as the Orion-class were seen as the perfect orbital assault ship; its planetary assault role, and so having also SOEIV drop pods, was left to the Phoenix-class, other than to various cruisers and frigates.
Now having well three air squadrons and new weapons, Orion performed well only with Cole, as the admiral used them, as well as Marathons, in anti-ship long-range artillery, so avoiding direct combat whenever possible. Then again, armor on these two class was extremely thin, if compared to the damage output released by plasma fire, so only two torpedoes could destroy or severely damage them.
After Covenant began to onslaught Inner Colonies, UNSC High Command decided to organized long-range battle groups in order to distrupt Covenant supply lines and staging areas; Orions were suitable for this task due to their internal factories, which could replenish all those battlegroups indefinitely. However, that ambitious plan hadn't much success, and many ships, including Orions, were lost.
== Specifications ==
=== Hull ===
=== Powerplant ===
=== Crew and complement ===
=== Other systems ===
=== Armament ===
== Roles ==
== Ships of the line ==