UNSC Pillar of Autumn

The Pillar of Autumn (CL-709) was a Halcyon-class light cruiser in service with the UNSC Navy during the Insurrection and the Great War. It was the sister ship of UNSC Dawn Under Heaven and UNSC Toulouse.
== History ==
=== Construction ===
The Pillar of Autumn was constructed at the Reyes-McLees Shipyards on Mars. The ship began construction in 2507, was completed in 2509, and was launched on December 1, 2510. Alongside her sister ships, the Dawn Under Heaven and Toulouse, the Autumn was among the last of her class to be commissioned.
=== Great War ===
In 2530, the Pillar of Autumn, as with most surviving Halcyon-class cruisers, was refit and reactivated to bolster the fleet as the Galactic Empire continued to advance through UEG space.
During the Battle for Arcadia in February 2531, Pillar of Autumn engaged two Imperator-class battleships alongside the UNSC Belfast, UNSC Texas and UNSC Armstrong. Along with the other three cruisers, Pillar of Autumn destroyed one of the battleships after catching it with its shields down, but the other was able to retreat to the surface of the planet. During the later stages of the battle, Pillar of Autumn was badly damaged along with Armstrong while Texas and Belfast were destroyed.
The Autumn was eventually decommissioned, but was reactivated as the war worsened, being pulled from long-term storage in 2550 to serve as an emergency support ship in a conflict near Zeta Doradus.
=== Final mission ===
Prior to the Fall of Reach, the Pillar of Autumn was selected to support Operation: RED FLAG. Captain Jacob Keyes was placed in command due to his exemplary performance in battle. The operation was forestalled by the 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 Iota Horologii system by the smart AI Cortana. There it was engaged by an Imperial fleet guarding Installation 04. Keyes crash-landed the ship on the installation where the surviving crew continued the battle against Imperial forces. The ship's sole remaining combat-effective Spartan-II, John-117. was forced to manually activate the Autumn's self-destruct system, destroying both the ship and the ringworld, to prevent the Installation from being fired.
== Design details ==
=== Superstructure ===
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. Following its refit in 2552, the Autumn had a substantially expanded SOEIV launch bays and its hull was reinforced with the latest ablative armor plating. Located at the ship's bow are slipspace navigation sensors and hardened proselytization network transponders. A planetary scanning array, incorprating planetary survey sensors and probe/satellite launchers, is mounted just below its bridge. At the very top of the engine cowling is a multipurpose scan array, which contains tactical sensors and an electronic eavesdropping suite.
=== Power plant ===
At the time of her launch, the Pillar of Autumn was equipped with four Hanley-Messer second-generation Naval fusion reactors, which supplied only 10% the power of the Westinghouse seventh-generation Naval reactors aboard Marathon-class cruisers. Wartime refits replaced these with General Atomics fourth-generation reactors. During her refit for Operation: RED FLAG, the ship was refitted with four prototype eighth-generation reactors manufactured by Boglin Fields, which were capable of boosting their overall power output by 300% for brief periods by overlapping their magnetic fields. The reactors were paired with an experimental cooling system, using a laser-chilled ion slurry, which was far more efficient than the typical method of expendable chemical temperature-control substances. 
=== Armament ===
The Pillar of Autumn's original armament, like all ships of her class, comprised a Mark III, light-coil 56A2D4 Magnetic Accelerator Cannon, twenty M42 Archer missile pods, ten Mk VII 12-inch/45 caliber railgun batteries, and seventy-five M620 Buttress 30mm autocannons. Wartime refits upgraded the MAC to a Mk III, heavy-coil 67B3E5, and updated the ship's secondary armament to thirty-two M58 missile pods, ten Mk XII 12-inch/50-caliber railgun batteries, and one hundred M710 Bulwark 40mm autocannons.
The Pillar of Autumn once again received extensive refits in preparation for Operation: RED FLAG, including an armament scheme far in excess of even a Marathon-class cruiser.
* One Mark III, heavy-coil 67B3E5 MAC, modified with additional booster capacitors and magnetic field recyclers, allowing three consecutive shots to be fired per charge.
* One-hundred M58 Archer missile pods - 3,000 missiles.
* Forty Mk XXV 14-inch/45 caliber railgun batteries.
* One-hundred-fifty M910 Rampart 30mm point-defense guns with enhanced targeting scanners.
* Four Shiva-class Mk 17 nuclear kill vehicles (80 megatons).
* Four Fenris-class nuclear missiles (5 megatons).
* Eight Havok-class nuclear missiles (15 kilotons).
Category:Daisy-023
Category:Spacecraft