UNSC Pillar of Autumn
Pillar of Autumn redirects here. For more articles of the same name, see Pillar of Autumn (disambiguation).
UNSC Pillar of Autumn, (hull classification symbol C-709), was a Halcyon-class light cruiser in the UNSC Navy. It was informally referred to as the Autumn, and, in some cases, the Pillar. It was the sister ship of UNSC Dawn Under Heaven and UNSC Toulouse.
Prior to the Fall of Reach Pillar of Autumn was selected to support Operation: RED FLAG, a SPARTAN-II mission to capture Covenant leaders. Captain Jacob Keyes was placed in command. The operation was forestalled by the Covenant assault on Reach; the cruiser carried some of the few UNSC survivors and fled the system having lost most of its intended SPARTAN-II passengers.
The cruiser was guided to the Soell system by the smart AI Cortana. There it was engaged by a Covenant fleet guarding Installation 04. Keyes crash-landed the ship on the installation where the surviving crew continued the battle against the Covenant, and later, the Flood. The ship's sole remaining combat-effective SPARTAN-II, John-117, was forced to destabilize the Autumn's fusion reactor, destroying both the ship and the ringworld, to prevent the Installation from being fired.
During the Battle for Arcadia in February 2531, Pillar of Autumn engaged two CCS-class battlecruisers alongside the UNSC Belfast, UNSC Texas and UNSC Armstrong. Along with the other three ships, Pillar of Autumn destroyed the battlecruiser designated CCS-U321 after catching it with its shields down, but the battlecruiser designated CCS-U624 was able to make it to the surface of Arcadia. In the battle between the UNSC and Covenant forces, Pillar of Autumn was badly damaged along with Armstrong while Texas and Belfast were destroyed. Upon the arrival of the UNSC Spirit of Fire, the smart AI Serina reported on these events to Captain James Cutter. Later in the battle, at the request of Spirit of Fire, Pillar of Autumn contributed several M145D Rhinos to the ground battle, enabling Spirit of Fire's forces to take down a Covenant energy shield.
The cruiser was decommissioned with the remaining Halcyon-class light cruisers, but was reactivated as the war worsened. Pillar of Autumn was pulled from long-term storage and was refitted in 2550 to serve as an emergency support ship in a conflict near Zeta Doradus.
A chariot for Spartans
By 2552, it was obvious to the UNSC that the war could not be ended with conventional military action. A desperate plan, known as Operation: RED FLAG was conceived to end the war by capturing Covenant leaders and forcing the enemy to the negotiating table. A colony world would be sacrificed to the Covenant to allow SPARTAN-II commandos to board and disable a Covenant ship, locate the Covenant homeworld, and abduct the targets. Pillar of Autumn was selected on August 25 by the AI Cortana to disable an enemy ship and deliver the Spartans aboard; the ship was selected for the Halcyon-class's durability, despite its class's usual lack-luster offensive capabilities. Command of the ship was given to Captain Jacob Keyes.
The cruiser received another refit designed by Senior Engineer Adam Crokett for the new mission, including a state-of-the-art fusion power plant and improved weaponry. Furthermore, the command bridge was upgraded with a Tier III datacore to house Cortana and the drop pod bays were significantly expanded. After the refit, Cortana was transferred to handle the shakedown.
Fall of Reach
Pillar of Autumn was prepared to deploy on August 30. However, before it could depart the Epsilon Eridani system it was recalled to Reach; the UNSC fleet was mustering in preparation for an imminent Covenant attack on the planet. However, Cortana remained in control as the ship's normally assigned AI was not yet operational. At the opening of the battle, the Pillar of Autumn was engaged by a DDS-class carrier and quickly destroyed it with its modified MAC gun.
It was hoped an opportunity to capture an enemy ship would present itself, however, the course of the battle forced the Spartans to deploy on other missions. Blue Team went to Reach's Gamma Station to enforce the Cole Protocol, while Red Team went planetside to reinforce the orbital defense generators. While the cruiser performed well, the battle was lost as the orbital defense platforms fell silent. There was only time to recover the remnants of Blue Team (John-117 and the clinically dead Linda-058) and a Marine fireteam led by Avery Johnson that was also onboard Gamma Station, before the ship was forced to flee the system.
During the battle over Reach, the Pillar of Autumn attacked and destroyed a Covenant "sniper ship" in single combat. This prototype vessel was responsible for the destruction of many powerful UNSC warships. The unlikely victory of the Pillar of Autumn, for a brief moment, left her as one of the most successful and resilient ships in the Navy. However, the ship was heavily damaged in the fight and its main reactor was rendered inoperable.
At some point during the conflict, the Pillar of Autumn executed a Class-L flash-dock, landing at the Asźod ship breaking yards to rescue any survivors on the planet and retrieve a package which the remnants of NOBLE Team were tasked with delivering. During the battle, as NOBLE Team approached, the Pillar of Autumn used its point-defense guns to help clear the skies and sent forces into the drydocks to hold them. When Noble Six and Emile-A239 arrived, Emile manned an Onager mass driver set up by the UNSC forces to hold off the Covenant air support. After the UNSC forces took out Covenant attackers on a landing platform, Keyes personally led a Pelican to get the package. However, Emile was killed by a Sangheili Zealot and a CCS-class battlecruiser arrived to prevent the Pillar of Autumn from escaping. Using the mass driver, Noble Six destroyed the battlecruiser and the Pillar of Autumn was able to escape into space using R7 thrust couplings.
The Pillar of Autumn was supposed to have made a random Slipspace jump in accordance with the Cole Protocol. However, Cortana surreptitiously guided the ship to the Soell system and, ultimately, to Installation 04 instead. The AI used coordinates obtained from two Forerunner artifacts: one on Sigma Octanus IV, and one underneath Reach. The Covenant pursued along the cruiser's exit vector and arrived at Soell first with a battle group of CCS-class battlecruisers.
Battle of Installation 04
Pillar of Autumn was almost immediately engaged upon arriving at Threshold. The Prophet of Stewardship, who feared stray plasma torpedo fire might damage the holy artifact, ordered the boarding and capture of the cruiser. Fleet Master Thel 'Vadamee ignored this order and returned fire aggressively. Even so, the Autumn was able to destroy four ships and damage Truth and Reconciliation before boarders disabled its Magnetic Accelerator Cannon with an antimatter charge.
Captain Keyes ordered the crew to abandon ship. John-117 was given Cortana for safekeeping, and ordered to keep the AI out of enemy hands. The crew left the ship for the ring in whatever craft were available and the cryo pods were jettisoned. Keyes directed Pillar of Autumn on a course to crash land on the ring. The Covenant finally began hitting the ship with plasma torpedoes, but the cruiser survived the landing reasonably intact, though damaged beyond repair. The Covenant soon swarmed the ship and installed a security detail of two Banshees and six Ghosts to patrol the ship, though a massive raid led by Lieutenant Melissa McKay unseated the Covenant from the ship temporarily, allowing the survivors to transfer supplies from the ship to Alpha Base.
The release of the Flood added an unexpected dimension to the battle. Monitor 343 Guilty Spark was preparing to fire the Installation in response to the outbreak; in conjunction with the entire Halo Array this would wipe out all sentient life in the galaxy. John-117 and Cortana returned to Pillar of Autumn to destroy the ring by detonating the still-functioning fusion reactors. An attempt to activate the cruiser's self-destruct from the bridge failed due to 343 Guilty Spark's interference. The Spartan was forced to manually destabilize the reactors with tactical ordnance.
John-117 and Cortana escaped the subsequent detonation and the ring aboard a Longsword fighter still docked in Launch Bay 7. Pillar of Autumn exploded moments after their escape, blowing up a segment of the ring causing the entire Halo to fall apart; ultimately destroying Installation 04. The detonation itself left a huge crater, almost covering the entire width of the Installation itself.
The Autumn-class heavy cruiser, which entered service as the replacement for the Marathon-class after the Covenant War, was partially designed after the refitted Pillar of Autumn. Due to the instrumental role the Autumn played in the war, the lead ship of the new class was named UNSC Pillar of Autumn II in honor of the original.
In 2556, a fragment of the ring that escaped destruction called Alpha Shard was discovered. The supernova-like effects of the Autumn's detonation created a new element unique to the shard fatal only to humans. This element was mined by smugglers from Aleria and transformed into a bioweapon used on the Outer Colony of Sedra by terrorists. After the element was traced to Alpha Shard, Private Talitha Macer correctly surmised that the element was created by the explosion created when the Pillar of Autumn was destroyed. After this theory was confirmed, a joint ONI-Sedran Colonial Guard team underwent a mission to Alpha Shard, destroying the deposits of the new element with a HAVOK tactical nuclear weapon at the cost of most of the team.
Pillar of Autumn was roughly 43 years old at the time of its escape from Reach and later destruction on Installation 04. It was a cruiser of the Halcyon-class, the lightest cruisers in the UNSC Fleet.
The internal superstructure of Pillar of Autumn was designed by Doctor Robert McLees, though it was deemed unnecessarily over-massed and costly due to a series of cross-bracings and interstitial honeycombs. This led to the design being dropped from future models of Halcyon-class ships. Pillar of Autumn and 10 others out of 50 were built with this type of superstructure. The internal bracing structure allowed the ship to function even after sustaining critical levels of damage. Furthermore, the ship was fitted with an intraship transit system, which consisted of a network of lifts, stairs and mag-rail platforms. This allowed personnel to quickly travel through the ship. Following its refit in 2552, the Autumn had a substantially expanded SOEIV launch bays and its hull was wrapped in the latest Titanium-A ablative armor plating. Protruding from its front face is a foremast that is equipped with slipspace navigation sensors and hardened battlenet transponders. A planetary scanning array is mounted just below its Omega-pattern bridge, which is outfitted with planetary survey sensors and probe/satellite launchers. Four compact auxiliary fusion rockets are installed on either side of the cruiser, and while they are capable of a high-thrust, they are considered inefficient in their design. At the very top of the engine cowling is a multipurpose scan array, which contains tactical sensors and an electronic eavesdropping suite.
Prior to being refit for the Spartan mission, Pillar of Autumn was equipped with three Mark II Hanley-Messer deuterium fusion engines, which supplied only 10% the power of the standard 2552 UNSC Navy reactor. Pillar of Autumn was refitted with a set of improved nuclear fusion engines that featured two smaller reactors around a larger one, which were capable of boosting the overall power output by 300% for a short time if needed.
Fusion reactors generate extreme heat which must be removed in order for them to remain active without overheating. The Autumn's overhauled reactors were an especially severe case of this. Usually, the excess heat was conducted to a chemical agent which would then vent into space. However, the Autumn's upgraded specifications also included an upgraded cooling system, which featured a "laser-induced optical slurry of ions chilled to near-absolute zero", which was far more efficient than the typical method and removed the reliance on expendable chemical temperature-control substances. In essence, the amount of excess heat removed by the new system increased as the reactors' output did. This self-regulating and self-cooling power plant was critical in combat since it virtually eliminated a commander's concerns about overheating and slagging a ship's engines.
Pillar of Autumn's reactors were able to be overloaded by explosives, either grenades or rockets, destroying the vulnerable vent cores. Once these were destroyed, the reactors began to go critical, resulting in temperatures of over 100,000,000 degrees and a thermonuclear explosion large enough to tear apart a Halo installation. This explosion was later revealed to be similar in nature to a supernova and resulted in the creation of a new element on a surviving shard of the installation.
Prior to being refit for the Spartan mission, Pillar of Autumn had just one regular MAC gun and six Archer missile pods. The upgraded Pillar of Autumn received extensive refits, including several to its weapons systems. Eventually, it was host to a very powerful armament; far in excess of the original Halcyon-class ships.
Pillar of Autumn's engine room was a large, three-deck high chamber allowing access to the fusion engine core. Side passages allowed for movement from the bottom deck all the way up to the catwalks on the third. The manifolds into the cores were suspended above the second deck. Controls on the third retracted these manifolds, exposing a vent that led directly into the core. It was using this method to expose the core via the vents that the John-117 ultimately destroyed the ship and Installation 04. This room is the largest room in Pillar of Autumn with the exception of the hangar bay and the "leap of faith" room.
The Pillar of Autumn had a complement of six hundred Marines and four hundred ODSTs, totaling 1,000 fighting personnel. The ship's Marine complement were divided into the following units;
The ship's 400 ODSTs were divided under the following units;[note 3]
The following ODST units have a currently undefined place within the existing command structure;
Naval Pelican dropship pilots were assigned to the Pillar of Autumn from the 23rd Naval Air Squadron.
List of appearances