UNSC Navy

The UNSC Navy (UNSCN) is a human naval force, and one of four military branches of the UNSC. It is responsible for all naval operations in space, including but not limited to: interstellar transportation, ship-to-ship combat, deep-space law enforcement and expeditionary operations. Along with the UNSC Marine Corps and elements of the Aerospace Force, its field units fall under the authority of the unified Naval Command.

The Navy was birthed in response to the widespread violence that predated the Interplanetary Wars, and quickly grew due to the influx of assets and personnel belonging to the defunct United Nations Colonial Peacekeeping Force and various international armed forces. At first, riots and unrest in the Sol system meant that they remained largely confined to the region for the first two centuries of existence. Throughout the twenty-fifth century, they expanded rapidly to become the largest human-dominated naval force in history, thanks to successful attempts at usurping the existing Colonial Navy. They played a major role in both the Inner Colony Wars and the Insurrection, where they enforced sanctions on rebelling colonies, transported counter-insurgency units to trouble-spots, and delegated ships to protecting and searching civilian vessels. The UNSC Navy was authorized to take control of all naval assets and personnel at the beginning of the Human-Covenant War. In spite of this, they took horrendous losses at the hands of the Covenant; even with replacements, their fleet dropped from 2,034 ships to only 489 slipspace-capable warships at the conflict's conclusion.

Mission
Broadly speaking, the purpose of the UNSC Navy is to build and sustain a spacefaring naval force that can be used to promptly and efficiently wage war in space, using its fleet of large warships to further the interests of the UNSC itself. This primary mission involves maintaining UNSC presence in both inhabited and non-inhabited systems, in contrast to the UNSC Aerospace Force, whose responsibilities are concentrated around the colonies. To achieve this, they are obliged to train personnel to maintain and operate both warships and naval aviation arms, and must continue to evolve their understanding of naval theory, technology, and organization.

The UNSC Navy is also responsible for a number of supplemental missions, including but not limited to:
 * General transportation across space (spacelift)
 * Projecting UNSC influence across space (power projection)
 * Uncontested control of space and low-orbit regions (space control)
 * Search-and-rescue of both UNSC personnel and civilians in space
 * Civilian navigation control
 * Navigation and interstellar communications maintenance and support

Post-Covenant War
In the wake of the Human-Covenant War, the UNSC Navy emerged with a fleet of less than 500 slipspace-capable warships, and an industrial base that was unable to sustain a major expansion that was pressed by the admiralty. This was to the point that the Navy was given special permission to temporarily release funding worth 20 billion cR in 2553 alone to their suppliers, as many of them were at risk of bankruptcy without government support. Any battlefield replacements were only provided from the hulls that were either being fabricated on worlds that were not attacked, of which very few had significant numbers of drydocks, or miraculously saved during the battles of Reach, Tribute, and Mars. So lacking was the infrastructure that the largest collection of starship manufacturing facilities available for use immediately was the fleet of factory ships developed by the Reyes-McLees Corporation for Operation: OUROBOROS.

Meanwhile, the UNSC Navy was pressured by both the UEG and UNSC High Command to immediately begin preparations to reclaim the Human Sphere. In August 2553, the UNSC Navy conducted Operation: HIGH TIDE, an ambitious operation that aimed at retaking all star systems that could be reached from Sol and Epsilon Eridani systems, leaving only isolated pockets of occupied territories in the Inner Colonies. It emphasized exploiting the current state of civil war among the various Covenant factions by using prowlers to escalate the conflicts, before a huge lightning-fast push by the Fifth, Seventh, and Eighth Fleets would hopefully force them out of attacked regions. There were strict orders not to get bogged down in protracted conflicts, to avoid losing any ships. In addition, only the Second Fleet was initially available to secure any territory gained, although this would be strengthened as more ships were completed.

Command and control
The UNSC Navy's executive department is the Office of the Chief of Naval Operations (OPNAV), a constitute element of the UNSC High Command which is composed of the Chief of Naval Operations (CNO) and their staff; as such, it is also headquartered in UNSC Facility Bravo-Six in Sydney. As the single-highest authority available to the branch, OPNAV is capable of introducing branch-wide policies, including those affect otherwise self-contained departments such as the Office of Naval Intelligence. OPNAV also houses a lower-level division known as the Office of the Vice Chief of Naval Operations, which handles more specialized matters involving judicial, investigative, and minor legislative subjects. It is made up of:
 * Chief of Naval Operations (CNO), the de facto leader of the UNSC Navy
 * Vice Chief of Naval Operations (VCNO), who has the power to make any decision on naval matters that does not require the attention of the CNO.
 * Deputy Chiefs of Naval Operations (DCNOs), who represent and coordinate with the CNO on subjects relating to specific departments of the UNSC Navy.
 * DCNO of the Office of Naval Intelligence (DCONI)
 * Chief of Naval Personnel (CNP)
 * DCNO of Naval Operations, Plans, & Strategy (DCOPS)
 * DCNO of Fleet Readiness & Logistics
 * DCNO Integration of Capabilities & Resources
 * DCNO Warfighting Development
 * DCNO Warfare Systems
 * Master Chief Petty Officer of the Navy (MCPON), who represents the interests of the Navy's enlisted personnel.
 * Surgeon General of the Navy (SGN), who represents the UNSC Navy Medical Corps.
 * Chief of Navy Reserve (CNR)

The operating forces of the UNSC Navy, along with the Marine Corps and portions of the Aerospace Force, are then jointly coordinated by Naval Command (NAVCOM). Technically a series of administrative layers running from the top of the chain-of-command down to the Numbered Fleet and Division level, NAVCOM's primary purpose is to ensure the smooth and efficient progress of spaceborne operations by informing and coordinating with all parties involved in a given area. As a result, NAVCOM is not strictly a part of the Navy, and employs senior officers from all three branches for its planning. This offers a number of advantages not present in strictly-segregated command structures, such as streamlining the process of receiving support from another branch and vastly reducing instances of friendly fire. Its command structure is subdivided based on regions; Sector Commands relates to all assets in each given supersector of the Human Sphere, while Central Commands deals with 'subsectors' of vastly smaller regions. NAVCOM has a number of its own subdepartments; those relating specifically to the UNSC Navy include:
 * Fleet Command (FLEETCOM), which controls the ongoing strategy and tactical maneuvers of all of the Navy's warfighting vessels.
 * Naval Logistics Command (NAVLOGCOM), who support the upkeep, material transportation, and otherwise general maintenance of NAVCOM's combat assets.
 * Naval Special Warfare Command (NAVSPECWARCOM), which deploys special operations personnel and special projects belonging to all three branches.

Field formations
The UNSC Navy's organization for its starships has evolved and changed several times over the course of its lifespan, with the most modern iteration prioritizing easy reassignment of units and autonomy among its local headquarters spread throughout human space. Their naval forces are broadly divided into two main groups of formations, colloquially known as 'temporary' and 'permanent' forces. Temporary forces are custom-built for the needs of a single goal, and are immediately disbanded upon its completion. Permanent units are more general-purpose assignments whose duties are often locked within operational regions. They are only 'deactivated' when either their spacecraft are unavailable for assignment, moved to new commands, or are deemed impossible to practically support them in the foreseeable future. This does not always correspond to when moving ships are placed into temporary formations; squadrons assigned to task forces still retain their individual name and setup.

All permanent fleet formations are numbered, with the exception of Regional Fleets, who are named after the system they are homeported at. Temporary units such as Battle Groups have considerable freedom with what their callsign is, with some using the UNSC Military Alphabet-Number system (E.g. Battle Group Whiskey-Six), and others being named after their flagship (e.g. Battle Group Warspite).

Regional Fleets
Regional Fleets are the largest permanent formation of warships available to the UNSC Navy, whose mission is to defend one of the UNSC's headquarters systems, one for each FLEETCOM Sector and one for SolCore. They are commanded by either an Admiral or Fleet Admiral, who also is part of the local Central Command's leadership, and are generally composed of no fewer than 150 ships each. These ships are subdivided into two Numbered Fleets and a number of 'orphaned' squadrons and flotillas that are directly organized under it. Because of their vital objective, they have the power to requisition and fold any starship or fleet unit under their direct control without any prior approval, provided that they have are operating within the same sector. This power means that in theory, a Regional Fleet can consolidate and deploy thousands of ships in a single engagement, although the challenges in directing an armada of this size has prevented its practical use. While a necessary part of defensive plans, Regional Fleets see very little service outside of a handful of patrols into nearby regions that directly neighbor the system they are home-ported in. As a result, it is not uncommon for a considerable amount of ships to be detached into temporary Battle Groups, which are returned upon completion of their assignment.

Only five Regional Fleets have ever existed at any one time. {{Col-2

Active

 * Home Fleet: Assigned to SolCore; currently active.
 * Epsilon Eridani Fleet: Assigned to FLEETCOM Sector One.
 * Delta Pavonis Fleet: Assigned to FLEETCOM Sector 2; currently active, replaced the Ectanus 45 Fleet.
 * Beta Comae Berenices Fleet: Assigned to FLEETCOM Sector 3; currently active, replaced the Cygnus Fleet.

Inactive
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 * Ectanus 45 Fleet: Assigned to FLEETCOM Sector Two; destroyed during the Siege of Chi Rho.
 * Cygnus Fleet: Assigned to FLEETCOM Sector Three; destroyed during the Siege of Paris IV.
 * Bhaakto Fleet: Assigned to FLEETCOM Sector Four; destroyed during the Siege of Alluvion.

Numbered Fleets
Numbered Fleets are large naval formations that are made of between 50-90 ships, which are organized into four or five Groups and a handful of Squadrons and Flotillas for further support. They are commanded by Vice Admiral, and are intended as an autonomous, multipurpose force that could undertake a number of objectives over a reasonably broad region of space. Their leadership structure is designed to operate completely independently without any orders for extended periods of time, and their field endurance is also similarly improved over smaller units thanks to an integrated logistics division. As a result, Numbered Fleets are most often called upon to conduct major expeditionary campaigns away from their home ports, and may be temporarily reassigned to hub colonies for the duration of a given mission.

Unlike in smaller Groups or Squadrons, the sheer numbers of ships, fighters, and personnel assigned to Numbered Fleets makes it impossible to coordinate them under a single bureaucratic layer. The fleet's command staff therefore disseminate their orders below into a number of subordinate divisions. These are typically organized into commands for conventional naval forces, logistics, aviation arms, and intelligence, with the UNSC Marine Corps also being briefed here due to their close working relationship. Through these, the Admiral can issue necessary instructions to various parts of the fleet, focusing on the larger strategic picture while lower divisions plan the actual tactical micro-management that needs to take place. Multiple departments can work together to create cross-command units with the same orders, thanks to a unified rank structure and shared policies. This is out of sheer necessity, as while subordinate units can operate alone, their longer-term endurance is compromised.

The most common configuration of Numbered Fleets is made up of three Carrier Strike Groups, one Assault Group, and one Logistics Group at their core, which is then supported by two standard Flotillas and two Cruiser Squadrons. However, the ease in which Numbered Fleets can be tweaked allows for any combination of Groups, Squadrons, or Flotillas to be pulled together based on regional need.

Group
A Group is made up of two-three Squadrons or Flotillas which are attached to a heavy-tonnage capital ship such as a battleship or carrier, and are commanded by a Rear Admiral (O-8 rating). They are specialized units optimized to fulfilling a specific role that the fleet needs fulfilled, such as logistical support, mobility warfare, and electronic warfare, with only those that operate in the same broad field being coordinated through the same fleet department. All Groups also have a Prowler permanently attached to them, to provide better situational awareness and disrupt opponents during combat. After the Human-Covenant War, due to the immediate lack of warships to create full-strength fleets, there were talks of abolishing Groups and introducing heavy capital ships into Squadrons, although this never came to pass.

All Groups are made up of templates, which are mixed-and-matched within a given fleet to tweak their performance towards a designed set of roles. This makes it easier to hammer out procurement bills in the UEG Senate.

Squadrons
Squadrons are the workhorse formation of the UNSC Navy, and are generally used for any task worth sending a warship towards. They are commanded by a Commodore (O-7 officer), and are composed of no more than eight warships led by a single capital ship, generally a cruiser or medium-tonnage carrier. As they are on the lowest rung of the naval chain of command, Squadrons are most concerned with achieving immediate orders issued to them, often by sending deliberate tasks to each ship under their command. In addition, their complements may also be directly micro-managed to optimize the chances for success, although most Commodores are content with leaving those tasks to each Naval Aviation or Marine Corps officer.

Flotillas
A Flotilla is a specialist unit, defined in that it is made up of 5-13 vessels, with none of these being considered capital ships. They are usually commanded by Commodores (O-7) or Captains (O-6), who typically takes to the field aboard a destroyer leader or another type of small command ship. They are the least manpower-intensive formation available to the UNSC Navy that are do not sacrifice their ability to complete battle tasks, and are generally deployed to second-line tasks such as counter-piracy deployments and convoy escorts. Because of the small size of their ships, they generally have short ranges and operating times, requiring them to be cycled out or paired with a dedicated replenishment ship to improve their endurance.

Battle Groups
A Battle Group is a temporary, ad hoc naval formation, which are formally created by the UNSC Navy in order to achieve a specific goal, where they would be dissolved upon completion. In contrast to permanent fleet units such as Squadrons, there are no rating requirements for the commanding officer of a Battle Group, only that they must have a higher rank above that of their subordinates. They can be of any size, with the smallest being composed of merely two ships, while the largest could rival Numbered Fleets in size. Because the only branches involved answer to the UNSC Department of the Navy, they follow the regular naval chain-of-command. Units which are integrated into Battle Groups without modification, such as a Flotilla, generally retain their name and operating structure to keep things running smoothing.

Shore installations
In addition to their ships and fleets, the UNSC Navy also operates a number of space stations and planetside facilities, which are devoted to supporting naval operations on a permanent basis. These vary greatly in size and purpose, but all fulfil vital roles such as training new personnel, maintaining and refueling warships, and further research new technologies and doctrines. While they usually cluster themselves around inhabited colonies, they also operate a number of deep-space platforms for a variety of reasons. Although many facilities house high-level NavCom staff, such as Bravo-Six in Sydney, the personnel within occupy a separate level above them. A large number of their personnel is also made up of non-enlisted civilians.

Shore installations are generally organized into their own bespoke commands. Directly coordinated beneath UNSC Central Commands are Naval Bases, which encompass all Navy-owned installations within a localized star cluster. They are commanded by Rear Admirals, although Vice Admirals may take charge when they are particularly large. The next level down are specialized departments that specifically concern themselves with specialized subjects, which depending on their size can be commanded by Commodore Admirals down to mere Commanders. Examples includes the Naval Education and Training Command and the Naval Meteorology, Oceanography, and Astronomy Command. It is after this point where you finally reach the individual stations and bases, which are generally led by Captains.

Navy aviation
The UNSC Navy's in-house aircraft division is specifically optimized for the task of conducting space fighter attacks from mobile warships, although they do operate a number of strikecraft and shuttlecraft from shore installations as well. They have a very close working relationship with the UNSC Marine air units, due to the fact that both are used during expeditionary operations. All carriers operated by the UNSC Navy are commanded by navy aviation officers, as it is felt that their experience would allow them to better coordinate their onboard squadrons.

Navy aviation forces are well-integrated into the regular chain-of-command, and do not have any independent structures that exist outside of a given warship. Their formations are smaller than those operated by the Aerospace Force, as there is not enough space on most warships to accommodate them. The smallest units they operate are flights of two-four aircraft, which are led by a Lieutenant. Three to four flights form a squadron, which are led by a Lieutenant Commander. A Group is the next level up, and is composed of more than two squadrons. These are commanded by a Lieutenant Commander. A Wing is generally the largest unit they will use, which are made up of at least two groups and are led by a Commander. All navy aviation units are numbered, with the exception of flights, which use the UNSC military alphabet instead as their callsign.

Navy reserve
The Navy reserve is the non-active-duty component of the branch, generally made up of individuals who are too old, unfit, or otherwise unwilling to commit themselves to full-time service. It serves two main purposes; firstly, they operate the second-line, system-specific assets within the UNSC Navy, such as maritime warships and spatial patrol ships. This allows the branch to establish a secure presence in each star system without drawing manpower away from their fleets and shore installations. Secondly, it provides military training to a wider portion of the population that can be used to bolster the UNSC during times of war, bypassing the usual training period that new recruits would have to go through. Like all other reservist organizations, during wartime their personnel may be called upon to serve in an active-duty role, which was done during the Human-Covenant War.

Ships
The UNSC Navy divides its vessels into four tonnage tiers, with a fifth that is reserved for dedicated support ships; of these, supercapitals are by far the largest. Massing over 100 million metric tons in mass, these carry the heaviest naval weaponry and thickest armor of any warship in service, and are crewed by tens of thousands of sailors. These behemoths are typically used as fleet flagships, where they can safely protect the flag staff during battle. In the modern age, most such vessels are classified as supercarriers, which are hybrid vessels that combine the heavy weapons of a battleship with the air wing of a carrier. However, in recent years a number of superbattleships such as the have also been introduced, which remove their ability to carry fighters in favor of maximizing the amount of weapons they can carry.

The next largest are capital ships, which make up the core of any naval unit. These are still considered very powerful vessels, able to operate independently for extended lengths of time, and can undertake operations that would normally require a squadron of smaller vessels to achieve. The UNSC uses a number of different classes for their capital ships. Cruisers are extremely versatile spatial combatants, able to be pressed into a number of different roles without any loss in their combat abilities. Carriers are specifically employed to ferry space fighters, and would typically stay out of battle. Battleships are very heavily-armed and armored, although their slow speed makes them unattractive in regular fleet units. Battlecruisers such as the old are a half-way step between cruisers and battleships, and are used as the flagship of cruiser squadrons.

The bulk of the UNSC's fleet are made out of smaller vessels, generally massing between 500,000 to 2 million metric tons. Many are capable of operating without resupply for extended lengths of time, but they are intended to be used in sizable groups, where they use wolfpack tactics to defeat larger opponents. They are also needed to screen the larger capital ships from smaller, lighter vessels. The UNSC Navy primarily uses two classifications of ships for this task; frigates and destroyers. Frigates are lighter warships used for a wide variety of supporting tasks, ranging from troop transportation to scouting. They sacrifice armor for speed, and their weapons are usually chosen for their effectiveness against fighters and smaller opponents. Destroyers are similar, but they focus on heavy armor and weapons, making them far more formidable spatial combatants.

One oft-overlooked part of the UNSC Navy's arsenal is their fleet of small patrol ships. Many of these are system defense vessels that lack a slipspace drive, and individually pose little threat to even the most modestly-armed warship. These include gunboats for intersystem commerce protection, and corvettes for buoy tending and some fleet reconnaissance work. Prowlers such as the are particularly useful thanks to their enhanced stealth capabilities, ability to launch surprise attacks on unprotected convoys, and insert operatives into enemy territory.

The UNSC Navy also has a number of auxiliary support craft. This includes tenders for resupply in the field, mobile drydocks for repairing disabled vessels, and translight ferries for carrying ships through slipspace.

There are also a handful of maritime vessels still in use, although prior to the Human-Covenant War, these tended to be small and used only for shore support and waterborne commerce protection. Frigates and cutters armed with the odd missile cell and small-caliber naval autocannon proved ideal at this task for centuries. The UNSC Navy also operates a handful of maritime carriers and submarines, although it was only during the Human-Covenant War when they saw prominence again before dying out again.