Editing Halcyon-class light cruiser

{{Title|''Halcyon''-class light cruiser}}
{{Status|Canon}}
{{Infobox/Ships
|name            = ''Halcyon''-class light cruiser
|image           =[[File:HR-UNSCPillarOfAutumn-Side.png|300px]]
|caption         = 
|modules         ={{Infobox/Ships/Class
|hide-class           = 
|class identification = [[Hull classification symbol]]: '''C'''{{Ref/Book|Id=HCESGuide|Halo: Combat Evolved: Sybex Official Strategies & Secrets|Page=60}}
|class operator       = [[UNSC Navy]]{{Ref/Book|Id=Enc22|Enc22|Page=119}}
|class manufacturer   = [[Reyes-McLees Shipyards]]{{Ref/Reuse|Enc22}}
|class architect      = [[Robert McLees (ship designer)|Dr. Robert McLees]]{{Ref/Book|Id=Enc11|Enc11|Page=261}}
|class built          = 50{{Ref/Reuse|HCESGuide}}
|class in service     = 2510{{Ref/Reuse|Enc22}} - present
}}
|hide-characteristics=
|nocollapse      = Yes
|type            = [[Cruiser]]
|length          = {{Convert|3840.64|ft|m|sp=us|sigfig=6|disp=flip}}<ref name="H1GameData">'''Halo: Combat Evolved''' 3D model data</ref>{{Ref/Reuse|Enc22}}
|width           = {{Convert|1155.73|ft|m|sp=us|sigfig=5|disp=flip}}{{Ref/Reuse|H1GameData}}{{Ref/Generic|Id=data drop|[[Data drops]]|Detail=Data drop 5}}
|height          = {{Convert|1359.69|ft|m|sp=us|sigfig=5|disp=flip}}{{Ref/Reuse|H1GameData}}
|mass            = 11 million tonnes{{Ref/Reuse|Enc22}}
|power           =
|maneuver drive  =3 [[Mark II Hanley-Messer DFR]] [[fusion drive]]s{{Ref/Reuse|data drop}}
|slipspace drive =[[Shaw-Fujikawa Translight Engine#Series V CODEN|Series V CODEN SFTE]] {{C|main translight engine}}{{Ref/Reuse|data drop}}
|crew            = 1,000{{Ref/Reuse|Enc11}}
|complement      = 
|troops          = 
|hull            = [[Titanium-A armor]]{{Ref/Reuse|Enc11}}
|shielding       = 
|sensors         = 
|ew              = 
|armaments       = *Initial configuration
**1 [[Magnetic Accelerator Cannon]]{{Ref/Reuse|Enc11}}
**4 [[Shiva-class nuclear missile|Shiva missiles]]{{Ref/Reuse|Enc11}}
**180 [[Archer missile]]s{{Ref/Reuse|Enc11}}
*Alternate weapons configuration
**1 [[Magnetic Accelerator Cannon|Mark II 56A2D4 light MAC]]{{Ref/Reuse|Enc22}}
**4 [[Spitfire naval coilgun battery|Mark 33 Spitfire naval coilgun battery]]{{Ref/Reuse|Enc22}}
**4 [[Sentry autocannon|M66 Sentry autocannon]]{{Ref/Reuse|Enc22}}
**20 [[Archer missile|M58 Archer missile pods]]{{Ref/Reuse|Enc22}}
**40 [[M810 Helix point defense guns]] or [[M910 Rampart point defense network|M910 Rampart point defense guns]]{{Ref/Reuse|Enc22}}
|aircraft        = 
|air facilities  = 
}}
{{Quote|A dozen [[Covenant]] superior battleships against a single Halcyon-class cruiser. Given those odds, I'm content with three...make that four kills.|[[Cortana]] during the [[Battle of Installation 04]].<ref name="TPOA">'''[[Halo: Combat Evolved]]''', campaign level ''[[The Pillar of Autumn (Halo: Combat Evolved level)|The Pillar of Autumn]]''</ref>}}

The '''''Halcyon''-class light cruiser''',{{Ref/Reuse|Enc22}} known as the '''Human Attack Ship class C-II''' by the [[Covenant]],{{Ref/Novel|Id=TF|HTF|Chapter=Prologue}} is a [[United Nations Space Command]] cruiser starship classification designed by [[Robert McLees (ship designer)|Dr. Robert McLees]] before [[2507]], with a [[hull classification symbol]] of '''C'''. Originally designed for attack and defense role in mind,{{Ref/Book|Id=EVG|EVG|Page=42}} they were also capable of being used as troop and supply transports.{{Ref/Reuse|Enc11}}

Their service lives were short due to a unique hull design that was costly to construct and maintain with low maneuverability, poor armament, and concerns about their tactical viability. They were replaced by the {{Class|Marathon|cruiser}} and later the {{Class|Autumn|heavy cruiser}}. Despite the disadvantages of the original design, the heavily modified {{UNSCShip|Pillar of Autumn}} proved to be one of the most effective, and costly, ships deployed in the war.

==Overview==
===Design details===
[[File:HWF PillarOfAutumn CrossSection.jpg|thumb|left|300px|A cross-sectioned view of the ''Pillar of Autumn''.]]
Maintaining the monolithic hull design of other UNSC cruisers, the ''Halcyon''-class were visually distinguished by their composition of five hexagonal and octagonal hull sections, each of which stacked on top of each other and progressively grew as they ran towards the engines. The frontmost surface of these cruisers was dominated by a long antenna structure called the foremast, whose base sat below the muzzle of the MAC. The [[bridge]] was slung underneath the front section on a portruding structure, which made it very vulnerable to enemy fire. The second-last hull section possessed four [[hangar bay|docking bay]]s that ran down either side like an equatorial line, and the keel featured a drop bay capable of deploying both [[SOEIV]] and dropships. Personnel made use of lifts, stairs, and mag-rail platforms for quick transit around the cruiser.{{Ref/Reuse|WFPoA}} To evacuate personnel during emergencies, these cruisers had at least 18 [[Class-3 Bumblebee]]s.

The aftmost section was largely devoted to the cruiser's propulsion and powerplant systems, which as originally installed were three [[Mark II Hanley-Messer DFR]]s.{{Ref/Reuse|data drop}} Designed for bulk manoeuvring rather than speed,<ref>'''[[Halo Mythos]]''', ''page 94''</ref> they were woefully obsolete by 2552, only capable of providing a tenth the output of more modern systems.<ref name="FoRC25">'''Halo: The Fall of Reach''', Chapter 25</ref> They were complemented by four compact auxiliary fusion rockets mounted in pairs, which could provide high thrust but were dogged by inefficiency.{{Ref/Reuse|WFPoA}} Combined, they gave the ''Halcyon''-class a profound lack of speed, and coupled with their minimal firepower they were ineffective in combat.{{Ref/Reuse|FoRC25}}

The most curious element of the ''Halcyon''-class was their unusual frame construction. Designed by [[Robert McLees (ship designer)|Doctor Robert McLees]], they made use of a series of internal cross bracings and [[Titanium-A armor|Titanium-A]]{{Ref/Reuse|FoRC29}} honeycombs. This feature gave the class a reputation for enduring serious punishment, despite their usage of older, heavier armor that provided less protection than modern standards. ''Halcyon''-class cruisers were known to remain operational despite suffering breaches to all compartments and losing 90% of their armor. However, such a scheme was costly and grossly overmassed compared to more conventional measures, which led to it being dropped after the first eleven cruisers.<ref name="FoRC25">'''Halo: The Fall of Reach''', Chapter 25</ref> Aiding in this, corridors aboard the ''Halcyon''-class possessed retractable containment bulkheads which could seal off breached or overrun sections of the ship.<ref name="maw">'''[[Halo: Combat Evolved]]''', campaign level ''[[The Maw]]''</ref> During emergencies, the environmental systems could vent each section to asphyxiate the occupants within.{{Ref/Novel|Id=TFC1|HTF|Chapter=1}} The ship was pocketed with numerous maintenance and service corridors that ran the length of the ship. If necessary, these expansive corridors, including a [[Class Seven service corridor]] running along the dorsal structure of the vessel, could permit passage to [[Warthog]]s and some sections were large enough to accept [[Pelican]]s.{{Ref/Reuse|maw}}

There were two distinct visual varieties of ''Halcyon''-class cruisers: the earliest version of the cruiser had a rather smooth and flat construction,{{Ref/Reuse|TPOA}} while later portrayals incorporated cut-out portions and often featured [[Spitfire naval coilgun battery#Mark 33 Spitfire|Mark 33 Spitfire naval coilgun battery]].

''Halcyon''-class cruisers were constructed in space and are not rated for atmospheric deployment.{{Ref/Reuse|TFC1}} If necessary, detachable [[R7 thrust coupling]]s could provide them with limited atmospheric flight.<ref name="ReferenceA">'''Halo: Reach''', campaign level ''[[The Pillar of Autumn (Halo: Reach level)|The Pillar of Autumn]]''</ref>

===Armament===
The ''Halcyon''-class was by far the most lightly-armed of the UNSC's cruiser classes, being armed with only one [[Magnetic Accelerator Cannon]], 180 [[Archer missile]]s, and four [[Shiva-class nuclear missile]]s.{{Ref/Reuse|Enc11}}

An alternative armament scheme provided the ''Halcyon''-class with a single Mark II 56A2D4 light MAC as its primary weapon. This was bolstered with twenty [[M58 Archer missile]] pods, which was far below standards at the time. The class' firepower was further supplemented with four [[Spitfire naval coilgun battery#Mark 33 Spitfire|Mark 33 Spitfire naval coilgun batteries]] and four [[M66 Sentry autocannon]]s, with both types of turrets featuring two barrels each. The ''Halcyon''-class cruisers could also be equipped with forty point defense guns, using either the [[M810 Helix point defense gun|M810 Helix]] or the [[Rampart point defense gun#M910 Rampart|M910 Rampart]] point defense guns.{{Ref/Reuse|Enc22}}

===Refits===
{{Main|UNSC Pillar of Autumn#Design details}}
Although considered subpar ships, the pressure of the Human-Covenant War forced the UNSC to recommission and refit ''Halcyon''-class cruisers back into service. Generally, they received token armament upgrades through the installation of a MAC and an additional six Archer missile pods.{{Ref/Reuse|FoRC25}} However, when called upon substantially greater changes were authorised.

By far the most expansive and famous of these were the alterations the UNSC ''Pillar of Autumn'' received as part of preparations for Operation: RED FLAG. Selected due to its possession of the honeycomb framing scheme, the refit took advantage of the need to replace its hull plating with reformulated [[Titanium-A armor]], which reduced its mass but also freed up internal volume. Much of this would be taken up by hangars and [[SOEIV]] launch bays, although the former required the removal of long-term accommodations.{{Ref/Reuse|Enc22}} Power was improved with an experimental reactor setup that could not only increase output by up to 300% for short periods of time, but made use of a very efficient laser-induced ion cooling system. Armament was finally expanded, with a MAC capable of firing three times on the same charge,{{Ref/Novel|Id=FoRC29|FoR|Chapter=29}} 32 M58 Archer missile pods, 8 Mark 33 Spitfire naval coilgun batteries, and six M66 Sentry autocannons. 18 M910 Rampart point defense guns with overlapping fields of fire provided the final layer of protection against missiles and incoming munitions.{{Ref/Book|Id=WFPoA|HWF|Page=24-25}}

==Service history==
At just over 1.17 kilometers in length, the ''Halcyon''s were the lightest of vessels to be designated and structured as cruisers.{{Ref/Reuse|FoRC25}} Considered subpar compared to later ships, these cruisers only served for a handful of years before they were placed into long-term storage near [[Europa]],{{Ref/Reuse|Enc22}} and were eventually designated for scrapping.{{Ref/Reuse|FoRC25}} Some of these were scrapped even up until [[2552]], as the [[Asźod ship breaking yards]] were in the process of scrapping at least one ''Halcyon''-class cruiser by that time.{{Ref/Level|HR|Id=HRPoA|Pillar of Autumn}}

When the [[Human-Covenant War]] erupted in [[2525]] a number of ''Halcyon'' cruisers were reactivated from storage and refitted. Some participated in remarkably early engagements of the war; [[Preston Cole|Vice Admiral Cole's]] [[Battle Group X-Ray]] fought the [[Battle of Harvest]] with a number of these cruisers.{{Ref/Comic|HWG|Id=HWG}} Even this early on, it was evident that the ''Halcyon''s were not invulnerable; {{UNSCShip|Constantinople}} was lost with all hands during this battle. Meanwhile, the UNSC ''Pillar of Autumn'' took heavy damage when it teamed up with three other ships to destroy [[CCS-U321|a]] {{Pattern|Ket|battlecruiser}} during the [[Battle for Arcadia]].{{Ref/Level|HW|Arcadia City}} This led to a substandard performance record for the cruisers, and they'd come to be known as a joke within the [[UNSC Navy]].{{Ref/Reuse|FoRC25}}

''Halcyon''-class cruisers continued to serve throughout the conflict. As the losses continued to mount, the UNSC were forced to consider radical improvements to keep the ships competitive. The UNSC ''Pillar of Autumn'' received one such overhaul as part of the planned [[Operation: RED FLAG]], and used it to great effect during the subsequent [[Fall of Reach]], where it was instrumental to the destruction of a {{Pattern|Kewu|battleship}}.{{Ref/Novel|TFOR|Id=FoRC36|Chapter=36}} Later, during the approach to [[Alpha Halo]], it managed to destroy four Covenant [[capital ship]]s before being forced to crash onto the ring's surface, a phenomenal performance for a UNSC cruiser.{{Ref/Level|CE|Pillar of Autumn (Combat Evolved Level)|Pillar of Autumn}} Ultimately, the ''Autumn'' met its end when its engines were overloaded to destroy the Halo and much of the Covenant's [[Fleet of Particular Justice]],{{Ref/Level|CE|The Maw}} leaving behind only a handful of survivors.

The first of the {{Class|Autumn|heavy cruiser|heavy cruisers}}, commissioned into service following the end of the Human-Covenant War,<ref>'''[[Halo 4: The Essential Visual Guide]]'''</ref> would be built from the recycled hulls of surviving ''Halcyon''-class vessels.{{Ref/Book|Id=WFA|HWF|Chapter=Human, Cruisers}}

==Ships of the line==
Out of 50 Halcyon-class light cruisers built, the first 11 have the honeycomb superstructure while the other 39 have an unspecified construction.{{Ref/Reuse|HCESGuide}}

===Honeycomb superstructure===
This is the list of Halcyon-class light cruisers with the honeycomb superstructure:
*{{UNSCShip|Halcyon}} - The [[Wikipedia:lead ship|lead ship]] of the class.
*{{UNSCShip|Pillar of Autumn}} (C-709) - Participated in the [[Battle for Arcadia]] in [[2531]], destroying [[CCS-U321|a]] [[Ket-pattern battlecruiser|Covenant battlecruiser]] alongside three other human ships and providing ground support for the {{UNSCShip|Spirit of Fire}}. After refitting in [[2552]], the ''Autumn'', captained by [[Jacob Keyes]], was selected as the [[SPARTAN-II]]s' chariot for [[Operation: RED FLAG]], due to its new resilience and firepower. Destroyed by [[John-117]] in the [[Battle of Installation 04]] through wildcat destabilization of the engines, as a means to destroy [[Halo Array|Halo]] [[Installation 04]]. 

===Unknown superstructure===
This is a list of Halcyon-class light cruisers that haven't gotten their superstructure confirmed yet:
*{{UNSCShip|Constantinople}} - Participated and destroyed during the [[Second Battle of Harvest]] in [[2526]].
*{{UNSCShip|Dawn Under Heaven}} 
*{{UNSCShip|Persian Gate}} - Participated in the [[Battle of Alpha Corvi II]] in [[2526]].
*{{UNSCShip|Roman Blue}} - The first ship to be captained by [[Terrence Hood]]; participated in the [[Battle for Arcadia]].<ref>'''[[Halo: Escalation]]''', ''Issue #5''</ref> Shot down in battle between [[2535]] and [[2552]] and crashed on [[Eiro]]. Wreckage later salvaged by the ''[[Ace of Spades]]'' before an unknown vessel, possibly belonging to ONI, glassed ''Roman Blue's'' remains.<ref>'''[[Halo: Smoke and Shadow]]'''</ref>
*{{UNSCShip|Toulouse}} - Participated in an engagement over an unidentified [[Forerunner]] installation with a Covenant fleet.

==Trivia==
{{Linkbox|gallery=yes|gallerypage=Images of Halcyon-class light cruisers}}
*"''Halcyon''" is derived from the Greek word "''Alcyone''", which means "''marked by peace and prosperity''".
*The scrapped hulls of several ''Halcyon''-class cruisers can be seen in the ''Halo: Reach'' campaign level ''The Pillar of Autumn'' and the multiplayer map ''[[Boneyard]]''.
*The ''Pillar of Autumn's'' model from ''Halo: Reach'' is considerably larger than its original ''Halo: Combat Evolved'' counterpart. Indeed, it is longer than even the ''Marathon''-class cruiser.
*The ''Pillar of Autumn'' plays a role in ''[[Halo: Combat Evolved]]'', ''[[Halo: Reach]]'' and ''[[Halo Wars]]''. In each game, the ship provides support to the player in some form.

==Gallery==
<gallery>
File:PoA.jpg|The {{UNSCShip|Pillar of Autumn}}.
File:POA-InterdeckStructure.jpg|A vertical cross-section of a Halcyon-class ship, showing the honeycombed internal layout.
File:PelicanBay.jpg|A docking bay
File:PoA Crewmen.jpg|A typical internal corridor
File:Armory HCE.jpg|An [[armory]]
File:Origins - Defensive Measure.png|A Halcyon-class using its [[point-defense gun|50mm PDG]] against Covenant boarding craft in ''[[Halo Legends]]'': ''[[Origins]]''.
File:Boneyard Panorama.jpg|Halcyon cruisers sitting in a decommissioning yard on [[Reach]].
File:PoA Reach.jpg|The ''Pillar of Autumn'' in space in ''Halo: Reach''
File:HR_Holdout.jpg|A Halcyon class cruiser on the surface of Reach.
File:HR-UNSCPillarOfAutumn-Side.png|Right-side view of the ''Halcyon''-class light cruiser ''Pillar of Autumn'' in ''Halo: Reach''.
File:HR_PillarofAutumn_Drydock.jpg|Another view of a Halcyon class cruiser on [[Reach]].
File:HE13 Unknown Engagement.jpg|Halcyon-class cruisers during an unknown battle in ''[[Halo: Escalation]]''.
File:H2A -Halcyon.png|A ''Halcyon''-class light cruiser in ''[[Halo 2: Anniversary]]'' [[Terminal (Halo 2: Anniversary)|terminals]].
File:Halo Warfleet cover.jpg|The UNSC ''Toulouse'', on an early draft of the ''[[Halo: Warfleet]]'' cover.
</gallery>

==List of appearances==
{{Col-begin}}
{{Col-2}}
*''[[Halo: The Fall of Reach]]'' {{1st}}
**''[[Halo: The Fall of Reach#2010 bonus content|Adjunct]]'' {{Mo}}
*''[[Halo: Combat Evolved]]''
*''[[Halo: The Flood]]''
*''[[Halo 2]]'' {{C|Flashback}}
*''[[Halo: Contact Harvest]]''
*''[[Halo 3]]'' {{C|Memorial only}}
*''[[Halo Wars: Genesis]]'' {{Mo}}
*''[[Halo Wars]]''
*''[[Halo Legends]]''
**''[[Origins]]''
**''[[Odd One Out]]'' {{C|Non-canonical appearance}}
*''[[Halo: Evolutions - Essential Tales of the Halo Universe]]''
**''[[The Impossible Life and the Possible Death of Preston J. Cole]]''
{{Col-2}}
*''[[Halo: Reach]]''
*''[[Halo: Fall of Reach]]''
**''[[Halo: Fall of Reach - Boot Camp|Boot Camp]]''
**''[[Halo: Fall of Reach - Invasion|Invasion]]''
*''[[Halo: Combat Evolved Anniversary]]''
**''[[Terminal (Halo: Combat Evolved Anniversary)|Terminals]]''
*''[[Halo: Escalation]]''
*''[[Halo: Broken Circle]]'' {{Im}}
*''[[Halo 2: Anniversary]]'' {{C|Flashback}}
**''[[Terminal (Halo 2: Anniversary)|Terminals]]''
*''[[Halo: Fleet Battles]]''<ref name="orders">[https://www.halowaypoint.com/en-us/news/canon-fodder-taking-orders '''Halo Waypoint''': ''Canon Fodder - Taking Orders'']</ref>
*''[[Halo 5: Guardians]]'' {{C|Hologram only}}
*''[[Halo Mythos]]''
*''[[Halo: Fractures]]''
**''[[Into the Fire]]''
*''[[Halo: Smoke and Shadow]]''
*''[[Halo: Fireteam Raven]]''
*''[[Halo: Silent Storm]]'' {{Mo}}
*''[[Halo: Official Spartan Field Manual]]''
*''[[Halo: Lone Wolf]]''
**''[[Solace (TV Series)|Solace]]''
*''[[Halo: The Television Series Season Two]]''
**''[[Halo (TV Series)|Halo]]''
{{Col-end}}

==Sources==
{{Ref/Sources|2}}

{{Human Ships}}

[[Category:Halcyon-class light cruisers| ]]
[[Category:Cruiser classes]]
[[Category:UNSC ship classes]]