Ceudar-pattern heavy corvette

"What the hell are those things?"

- Cadet Thomas Lasky, upon seeing SDV-class heavy corvettes for the first time

The SDV-class heavy corvette is a class of corvette, formerly in service with the Covenant fleet. Manufactured by both the Forgemasters of Tanus and the Gorgon Assembly Vault, these corvettes rarely engage in ship-to-ship combat, though if pressed, they are capable of taking on human frigates on more-or-less even terms. Instead, SDV corvettes typically escort capital ships, deploy space fighters in fleet engagements, and screen support ships from enemy fast-attack craft. Although they typically serve as heavy escorts within a fleet, the SDV class can operate independently of support for extended periods of time.

Mass-assembled during the Twentieth Age of Discovery, SDV-class heavy corvettes were originally commissioned for charting distant stars and dangerous slipspace routes, or aiding the Covenant navy in war. During the Human-Covenant War, the SDV class saw heavy use against humanity, most prominently during the Fall of Reach. With the collapse of the Covenant Empire, these corvettes are now serviced by the Covenant's successors.

Superstructure and hull
"Scans indicate a structural weakness surrounding a platform on top of the vessel."

- Auntie Dot, referring to the SDV class

SDV-class heavy corvettes are relatively small warships once manufactured by the Covenant, with a length of 956 meters and a mass of 8 million metric tons. Like all Covenant vessels, these corvettes are armored with a lightweight, yet incredibly resilient, diamondoid and metal-matrix composite frame, covered by thin pieces of streamlined nanolaminate hull plating, Identifiable by their smooth oblong shape, the SDV-class heavy corvettes are assembled with a selvage rim, a contoured extension of the hull for additional protection that is also capable of deploying combat carapaces. The rim is visually reminiscent of Suban's qoerith slugs. SDV corvettes have a dorsal landing platform at the top of the ship, a noted structural weakness to the design of the corvette. Red and blue lights are used to distinguish the port and starboard sides of the ship. Mass-assembled in large numbers by the Covenant, the SDV-class heavy corvette has a highly flexible design pattern that can be modified for a number of specialized roles.

Unlike most Covenant warships, the cavernous war bridge of the SDV corvette is located in the bow of the ship, rather than the center. Referred to as the command center, the bridge is comparatively large and composed of an encompassing perimeter platform that surrounds a number of control consoles, with a holo-tank in the center and a retractable conference table off to the side. In addition to the bridge's high-tier auspex array and battlenet interlinks, the SDV class is also equipped with a long-range communication system near the center of the ship for synchronizing orders and edicts. Located at the corvette's midsection is the ministerial cloister, an elevated access point and common terrace for dignitaries and commanders. SDV corvettes have a highly advanced automated surgery suite typically capable of tending to most injuries. As most Sangheili prefer to avoid the medical bay, the suite is frequented more by other species.

The SDV class is outfitted with Morelia-pattern dispersal field generators,, which provide the corvettes with energy shielding. The corvettes are also equipped with a Ushab-pattern stealth generator, utilizing powerful distortion screens and a multispectral hypersink that renders the ships practically invisible to long-range passive sensors. A gravity lift near the center serves as a low-capacity utility lift for cargo transport.

Propulsion
SDV-class corvettes are highly regarded for their maneuverability and swiftness, using a combination of speed and stealth to infiltrate planetary defenses, though they are not as nimble as the s. The corvettes are fitted with four Callipoas-pattern repulsor engines, located at the aft of the ship. Providing sublight travel, these repulsor engines are configured for swift and agile localized transit.

For travel in slipstream space, the SDV class is outfitted with a Tyros-pattern borer—approximately equivalent to a CODEN Series VI Shaw-Fujikawa Translight Engine.

Crew and complement
SDV corvettes generally have a crew of thirty-eight, though these vessels are highly automated and only require a crew of ten for most operations. The crew consists of sixteen Superiors, twenty Menials, and two Huragok serving as the ship's engineers. SDV-class heavy corvettes are favored for their infantry transport and deployment capabilities. They can carry fifty Sangheili Obedientaries, another fifty Warriors, and one hundred-and-thirty Thralls. There are no long-term accommodations for the crew, except for those of the shipmaster. Instead, the crew use stimulants and dream-shapers to stay alert for their tour, before being rotated with fresh personnel at the end of the mission.

Corvettes of this class have a single multipurpose hangar bay, rated to handle heavy dropships and medium space fighters. These corvettes carry eight Type-31 Seraph fighters, locked onto the ceiling of its hangar bay. Seraph pilots may be trained by a skymaster. In addition, SDV-class corvettes carry ten Type-27 Banshee strikecraft and eight Type-26 Banshee support aircraft. Two Type-25 Spirit troop carriers are utilized by these corvettes to ferry troops to combat zones. SDV corvettes carry 104 insertion pods and deployment carapaces, deployed from the selvage rim. When launched, the drop pods benefit from a temporary signature reduction when passing through the ship's distortion screen.

Armaments
Armed with relatively light weaponry, SDV corvettes rarely engage in ship-to-ship combat, often deploying fighters to engage enemies while the corvette escapes. However, they are capable of engaging human frigates on more-or-less even terms, if pressed. The primary armament of the corvette is its array of six Melusean-pattern heavy plasma cannons, with three on either side of the ship. The plasma cannon array is capable of rapid fire, providing dynamic-range flank coverage. The SDV class is also armed with sixteen Carnax Nu-pattern plasma bombardment mortars designed for bombarding surface targets. For point defense, the corvettes possess eleven Phot-pattern pulse lasers. Some corvettes are armed with low-yield antimatter mines.

The "S" (for "Salvation") in the corvette's three-letter classification code indicates that the SDV-class heavy corvette is a dedicated warship capable of cleansing enemies of the Covenant with "holy fire", referring to its plasma bombardment capabilities.

Early service
The SDV-class heavy corvette was mass-assembled in large numbers by the Forgemasters of Tanus and the Gorgon Assembly Vault during the Twentieth Age of Discovery, an earlier era of glorious exploration for the Covenant. The corvette was designed by Master Shipwright Ckmu 'Raboree and Apprentice Hiveseeker Tek'ch—Sangheili and Yanme'e naval architects, respectively. Ardent Prayer was one of the corvettes assembled at this time, commissioned in around 2070.

The Covenant tasked the new SDV class with traveling to distant stars, charting dangerous routes in slipstream space, and battling civilizations that resisted the empire's vision of a Great Journey. Others were tasked with surveying Forerunner reliquary sites and deploying small artifact-retrieval teams to evade any active defensive measures. However, such matters were often considered beneath the attention of true warriors; while these corvettes played vital roles in the Covenant fleet, they possess no battle honors of note and are rarely mentioned in High Charity's records. Nonetheless, the SDV was a popular warship in the fleet, with entire battle groups comprised of these corvettes.

Human-Covenant War
During the Human-Covenant War, SDV heavy corvettes were utilized in front-line combat roles, as well as providing the Covenant fleet with long-range reconnaissance of potential naval staging areas and colonies. At least three SDV-class heavy corvettes were present during the Covenant's attack on the human colony of Circinius IV in 2526. During the battle, the three corvettes entered the planet's lower atmosphere over the Corbulo Academy of Military Science, where one of them fired on the school's space elevator, causing it to collapse. Several SDV corvettes participated in the Battle of Sigma Octanus IV in 2552, attached to the Second Fleet of Solemn Accord.

When the Fleet of Valiant Prudence arrived over Reach later that summer, several attached SDV-class heavy corvettes were present for the ensuring Fall of Reach. On July 26, 2552, a corvette attacked the Office of Naval Intelligence's Sword Base, but retreated when its forces were driven off. As it left, the corvette was struck amidships by a round from an orbital defense platform's MAC and sank in a nearby lake. At least four corvettes were present in the Covenant staging area in the Viery Territory. Later in the battle, Ardent Prayer played a vital role in Operation: UPPER CUT, when she was engaged by while being boarded by several YSS-1000 Sabre fighters, including one piloted by SPARTAN-B312 and Jorge-052. The pilots hijacked the corvette and brought aboard Savannah ' s slipspace drive, which was used as a makeshift bomb. Ardent Prayer was sent towards the fleet flagship Long Night of Solace, where Jorge-052 activated the drive and created a devasting slipspace rift. The resulting loss of Ardent Prayer and Long Night of Solace effectively crippled the Fleet of Valiant Prudence, though the fleet's remnants were reinforced by the Ministry of Resolution.

Other SDV-class heavy corvettes took part in later ground battles on Reach. At least three corvettes were present during the siege of New Alexandria. One took up position over the city's starport, preventing civilian evacuation transports from escaping. When one took off in desperation, the corvette shot it down. As the situation grew dire for the transports, SPARTAN-312 reactivated a missile battery which he used to fire on the corvette. The corvette was badly damaged and retreated, allowing the remaining civilian transports with thousands of people on board to escape. The corvette was last seen descending at a steep angle, indicating it may have crashed from the damage it sustained. Several of these corvettes also participated in the Covenant's attack on Tribute, with some assaulting its capital, Casbah.

Post-Covenant usage
Following the collapse of the Covenant, SDV-class heavy corvettes continued their service with surviving successor factions of the fallen empire. Jul 'Mdama's Covenant had several SDV-class heavy corvettes in its fleet. The Swords of Sanghelios also operated at least one corvette of the SDV class—Mayhem. This corvette was deployed on Operation: FAR STORM, delivering the joint forces of the Swords and United Nations Space Command to Installation 00 via the Portal at Voi.

In March 2558, Shipmaster Vata 'Gajat was using an SDV-class heavy corvette as the flagship of his mercenary faction, although both corvette and shipmaster were destroyed during the Oth Lodon incident. A Kig-Yar pirate queen operating on Ven III used an SDV corvette as her personal flagship, until its destruction in Operation: WHISTLE STOP. The Banished also maintained the heavy corvette Elegy's Lament in their fleet.

Ships of the line

 * Ardent Prayer – Captained by Shipmaster Ardo 'Moretumee as part of the Fleet of Valiant Prudence; destroyed during the Fall of Reach.
 * Elegy's Lament – Formerly in service with the Covenant fleet; captured by the Banished.
 * Mayhem – Captained by N'tho 'Sraom of the Swords of Sanghelios; heavily damaged during Operation: FAR STORM.

Halo: Fleet Battles
This element features two SDV-class heavy corvettes.
 * Line formation
 * Cost: 40 points
 * Movement: 9"
 * Damage Track: 4 • 4 • 3
 * Build rating: 1
 * Hangars: 1
 * Boarding Craft: 0
 * Security detail: 2
 * System loadouts:
 * Active camouflage
 * Defense array (2)
 * Elusive
 * Glide (5")
 * Point defense (3)
 * Primary weapon: Plasma cannon arrays
 * Range: 10/20"
 * Weapon loadouts: Plasma
 * Firing arc: Forward/Port/Starboard
 * Dice: 3
 * Secondary weapon: Plasma torpedos
 * Range: 10/24"
 * Weapon loadouts: Missiles/Plasma
 * Firing arc: Forward
 * Dice: 4

This element features two SDV-class heavy corvettes.
 * Oblique formation
 * Cost: 40 points
 * Movement: 9"
 * Damage Track: 4 • 3 • 3
 * Build rating: 1
 * Hangars: 1
 * Boarding Craft: 0
 * Security detail: 2
 * System loadouts:
 * Active camouflage
 * Defense array (2)
 * Elusive
 * Glide (5")
 * Point defense (3)
 * Primary weapon: Plasma cannon arrays
 * Range: 10/20"
 * Weapon loadouts: Plasma
 * Firing arc: Forward/Port/Starboard
 * Dice: 4
 * Secondary weapon: Plasma torpedos
 * Range: 10/24"
 * Weapon loadouts: Missiles/Plasma
 * Firing arc: Forward
 * Dice: 3

This element features three SDV-class heavy corvettes.
 * Tri formation
 * Cost: 60 points
 * Movement: 9"
 * Damage Track: 5 • 4 • 4
 * Build rating: 2
 * Hangars: 2
 * Boarding Craft: 0
 * Security detail: 3
 * System loadouts:
 * Active camouflage
 * Defense array (4)
 * Elusive
 * Glide (5")
 * Point defense (4)
 * Primary weapon: Plasma cannon arrays
 * Range: 10/20"
 * Weapon loadouts: Plasma
 * Firing arc: Forward/Port/Starboard
 * Dice: 6
 * Secondary weapon: Plasma torpedos
 * Range: 10/24"
 * Weapon loadouts: Missiles/Plasma
 * Firing arc: Forward
 * Dice: 6

Behind the scenes
"For Reach's corvette, artist Glenn Israel created something new yet familiar using motiffs from the Covenant cruiser."

- Frank O'Connor

The SDV-class heavy corvette made its visual debut in the 2010 game Halo: Reach, playing an integral role in the campaign level "Long Night of Solace", as well as serving as the setting for the Firefight map "Corvette" and the multiplayer map "Zealot"—both taking place aboard the corvette Ardent Prayer. For the game, the corvette was conceptualized and designed by artist Glenn Israel, who attempted to create a new, yet familiar, ship class. The corvette's design was partly inspired by the, particularly Truth and Reconciliation which had previously served as a setting for Halo: Combat Evolved. While the corvette's interior resembles that of the battlecruiser, the increased processing power of the Xbox 360 allowed for significantly more detail. The design of the SDV-class corvette for Halo: Fleet Battles was achieved without using the Halo: Reach model for reference. The (which was designed for the game) features a "runner" amidships in reference to the corvette.

In the campaign level "Long Night of Solace", the player's Sabre is able to destroy a corvette's engines and laser turrets, encountering no resistance from shields. A corvette in "Exodus" is also crippled with a single missile barrage, again without any prior attack to shields. This stands in contrast to the in the final level, whose shields render it immune to damage until it exposes a weak point. However, later media Halo: Hunters in the Dark, Halo: Fleet Battles, and Halo: Warfleet all make reference to the SDV class being equipped with energy shielding.

List of appearances

 * Halo: The Fall of Reach
 * Halo: Reach
 * Halo 4: Forward Unto Dawn
 * Halo 4
 * Halo: Escalation
 * Halo: Hunters in the Dark
 * Halo: Fleet Battles
 * Halo Mythos
 * Halo: Tales from Slipspace
 * Hunting Party
 * Halo: Rise of Atriox