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{{Status|Canon}}
{{Status|Canon}}
[[File:HW MAC Strike.png|thumb|150px|A MAC round fired from space as part of [[orbital bombardment]].]]
[[File:HW MAC Strike.png|thumb|right|150px|A MAC round fired from space as part of [[orbital bombardment]].]]
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|1=[[Nils Thune]]
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|3=Governor Thune and Captain Ponder discussing MACs.{{Ref/Reuse|CH7}}
|3=Governor Thune and Captain Ponder discussing MACs.{{Ref/Reuse|CH7}}
}}
}}
The '''magnetic accelerator cannon''',{{Ref/Reuse|WFG}} also referred to as a '''mass accelerator cannon'''{{Ref/Reuse|CH7}} or '''MAC''', is a type of heavy weapon system employed by [[human]]ity, primarily the spacecraft of the [[United Nations Space Command]]. Within the UNSC, MACs are defined as a heavy weapon that fires multi-ton projectiles at extraordinarily high velocities from the bow of a capital ship, [[orbital defense platform]] or mounted driver emplacement. They are hard-hitting, but relatively short-ranged.{{Ref/Book|Id=EVG114|EVG|Page=114}}{{Ref/Book|Id=Enc22P384&385|Enc22|Page=115}}{{Ref/Site|URL=https://www.halowaypoint.com/news/the-new-halo-encyclopedia-is-out-today|Site=Halo Waypoint|Page=The New Halo Encyclopedia is Out Today|D=11|M=03|Y=2023}} MACs are coilguns employing Asynchronous Linear Induction Motor (ALIM) technology{{Ref/Reuse|EVG114}} and are typically used in military applications, though similar technology can be used in civilian [[mass driver]]s for industrial use.
The '''magnetic accelerator cannon'''{{Ref/Reuse|WFG}}, also referred to as a '''mass accelerator cannon'''{{Ref/Reuse|CH7}} or '''MAC''', is a type of heavy weapon system employed by [[human]]ity, primarily the spacecraft of the [[United Nations Space Command]]. Within the UNSC, MACs are defined as a heavy weapon that fires a sizeable ferric-tungsten round at supersonic velocities from the bow of a capital ship, [[orbital defense platform]] or mounted driver emplacement.{{Ref/Book|Id=EVG114|EVG|Page=114}} MACs are coilguns employing Asynchronous Linear Induction Motor (ALIM) technology{{Ref/Reuse|EVG114}} and are typically used in military applications, though similar technology can be used in civilian [[mass driver]]s for industrial use.


==Overview==
==Overview==
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===Operation===
===Operation===
[[File:Coilgun animation.gif|thumb|250px|An animation of a coilgun's operating principle.]]
[[File:Coilgun animation.gif|thumb|right|250px|An animation of a coilgun's operating principle.]]
MACs operate on the basis of a [[:Wikipedia:Coilgun|coilgun]]. When firing, a series of stacked coil motors are sequentially activated, propelling a projectile with vast amounts of kinetic energy.{{Ref/Reuse|WFG}} The construction of the weapon takes the form of a series of coiled conducting wires (or solenoids). When a solenoid is activated, the projectile is attracted to the coil. As the projectile reaches the coil, a second coil is activated, attracting the projectile further down the barrel of the gun. This process is repeated as the projectile travels the length of the gun, with each successive solenoid accelerating the projectile to higher and higher velocities. As such, the longer a MAC's length is, the faster the muzzle velocity of the fired projectile.
MACs operate on the basis of a [[:Wikipedia:Coilgun|coilgun]]. When firing, a series of stacked coil motors are sequentially activated, propelling a projectile with vast amounts of kinetic energy.{{Ref/Reuse|WFG}} The construction of the weapon takes the form of a series of coiled conducting wires (or solenoids). When a solenoid is activated, the projectile is attracted to the coil. As the projectile reaches the coil, a second coil is activated, attracting the projectile further down the barrel of the gun. This process is repeated as the projectile travels the length of the gun, with each successive solenoid accelerating the projectile to higher and higher velocities. As such, the longer a MAC's length is, the faster the muzzle velocity of the fired projectile.


This process differs from that of a [[Railgun (fiction)|railgun]] - a similar weapon system that feeds electrical current through a projectile to accelerate it along two conducting rails. Nonetheless, railgun weapon systems are occasionally referred to as MACs - as in the case of the Mini-MAC armament of the [[M510 Mammoth]].{{Ref/Reuse|H4IGMammoth}}{{Ref/Reuse|H4EVG115}}
This process differs from that of a [[railgun]] - a similar weapon system that feeds electrical current through a projectile to accelerate it along two conducting rails. Nonetheless, railgun weapon systems are occasionally referred to as MACs - as in the case of the Mini-MAC armament of the [[M510 Mammoth]].{{Ref/Reuse|H4IGMammoth}}{{Ref/Reuse|H4EVG115}}


To fire a MAC, UNSC ships must draw power from the [[fusion reactor]] into a series of capacitors, storing the generated energy for firing. As such, charging the MAC draws power away from other sub-systems such as engines. As such, a MAC can be pre-charged and fired when ready, though at the cost of power to the aforementioned systems. Without the charge being maintained, the charge level does deteriorate. However, MACs can be fired at lower charge levels than 100%{{Ref/Novel|Id=FOR17|FOR|Chapter=17}} though likely to lesser maximum velocity. Likewise, firing the weapon at lower charge rates would also allow the weapon to fire more often if needed.
To fire a MAC, UNSC ships must draw power from the [[fusion reactor]] into a series of capacitors, storing the generated energy for firing. As such, charging the MAC draws power away from other sub-systems such as engines. As such, a MAC can be pre-charged and fired when ready, though at the cost of power to the aforementioned systems. Without the charge being maintained, the charge level does deteriorate. However, MACs can be fired at lower charge levels than 100%{{Ref/Novel|Id=FOR17|FOR|Chapter=17}} though likely to lesser maximum velocity. Likewise, firing the weapon at lower charge rates would also allow the weapon to fire more often if needed.


===Ammunition===
===Ammunition===
MACs are capable of firing a wide array of munitions, depending on bore and model. Some MAC rounds are extremely dense and constructed of ferric tungsten,{{Ref/Reuse|EVG114}} noted by Captain [[Wallace]] of the frigate {{UNSCShip|Commonwealth}} as a "heavy round".{{Ref/Novel|Id=FOR12|FOR|Chapter=12}} In the case of the MACs fitted onto the refit-colony ship {{UNSCShip|Spirit of Fire}}, the rounds fired from its MACs are "low-mass"{{Ref/Book|Id=HWManual|Halo Wars Manual|Page=24}} or consist of three-hundred-ton depleted uranium slugs.{{Ref/Novel|Id=DW15|HDW|Chapter=16}} The MAC of the ''Spirit of Fire'' was later modified in a special project conducted by [[Ellen Anders]], resulting in a specialised MAC capable of firing rounds that emit an [[Electromagnetic pulse|EMP]] upon impact.{{Ref/Level|HW2|The Cartographer}} Other munitions that can be fired from MACs include semi-autonomous drone missiles{{Ref/Book|Id=WF32|HWF|Section=Destroyers|Page=32-33}} and for the larger 27 metre guns of {{UNSCShip|Infinity}}, even include cargo pods and small spacecraft.{{Ref/Book|Id=WF42|HWF|Section=[[UNSC Infinity|Infinity]]|Page=42-43}} A special kind of MAC round fired by the refit-{{UNSCShip|Pillar of Autumn}} was composed of a ferrous core and an outer layer of tungsten carbide, which allows the round to splinter on impact with an enemy vessel, similar to the [[shredder round]]s fired by an [[assault rifle]].{{Ref/Novel|Id=FOR29|FOR|Chapter=29}}  
MACs are capable of firing a wide array of munitions, depending on bore and model. Some MAC rounds are extremely dense and constructed of ferric tungsten{{Ref/Reuse|EVG114}}, noted by Captain [[Wallace]] of the frigate {{UNSCShip|Commonwealth}} as a "heavy round".{{Ref/Novel|Id=FOR12|FOR|Chapter=12}} In the case of the MACs fitted onto the refit-colony ship {{UNSCShip|Spirit of Fire}}, the rounds fired from its MACs are "low-mass"{{Ref/Book|Id=HWManual|Halo Wars Manual|Page=24}} or consist of three-hundred-ton depleted uranium slugs.{{Ref/Novel|Id=DW15|HDW|Chapter=16}} The MAC of the ''Spirit of Fire'' was later modified in a special project conducted by [[Ellen Anders]], resulting in a specialised MAC capable of firing rounds that emit an [[Electromagnetic pulse|EMP]] upon impact.{{Ref/Level|HW2|The Cartographer}} Other munitions that can be fired from MACs include semi-autonomous drone missiles{{Ref/Book|Id=WF32|HWF|Section=Destroyers|Page=32-33}} and for the larger 27 metre guns of {{UNSCShip|Infinity}}, even include cargo pods and small spacecraft.{{Ref/Book|Id=WF42|HWF|Section=Infinity|Page=42-43}} A special kind of MAC round fired by the refit-{{UNSCShip|Pillar of Autumn}} was composed of a ferrous core and an outer layer of tungsten carbide, which allows the round to splinter on impact with an enemy vessel, similar to the [[shredder round]]s fired by an [[assault rifle]].{{Ref/Novel|Id=FOR29|FOR|Chapter=29}}  


Due to this variation, the masses, velocities and sizes of MAC projectiles can vary, ranging from 10 metre-long, 160 ton models fired by frigates and cruisers,{{Ref/Reuse|CH7}} to 600 ton{{Ref/Reuse|EVG114}} depleted uranium models fired by {{Class|Paris|heavy frigate}}s{{Ref/Novel|Id=FS29|FS|Chapter=29}} up to 3,000 ton{{Ref/Reuse|EVG114}} super-heavy rounds{{Ref/Novel|Id=FOR33|FOR|Page=364}} accelerated to "point four-tenths"{{Ref/Note|Id=Point|Due to massively conflicting interpretations of this number, this page only lists the wording used in the original text of ''The Fall of Reach''.}} of the speed of light by the [[orbital defense platform]]s above [[Reach]].{{Ref/Novel|Id=FOR31|FOR|Chapter=31}} The MACs of {{UNSCShip|Infinity}} are additionally capable of firing various "sub-caliber" munitions (For example, three-thousand-ton slugs) for its massive twenty-seven metre bore, alongside some of the special types mentioned prior.{{Ref/Book|Id=HM132|HM|Section=Earth's Fleet|Page=132-133}} A type of 1,200 feet (366 meters) long MACs have a range of 10,000 miles (16,093 kilometers).{{Ref/Book|Id=EncP316|Enc09|Page=316}}
Due to this variation, the masses, velocities and sizes of MAC projectiles can vary, ranging from 10 metre-long, 160 ton models fired by frigates and cruisers{{Ref/Reuse|CH7}}, to 600 ton{{Ref/Reuse|EVG114}} depleted uranium models fired by {{Class|Paris|heavy frigate}}s{{Ref/Novel|Id=FS29|FS|Chapter=29}} up to 3,000 ton{{Ref/Reuse|EVG114}} projectiles accelerated to "point four-tenths"{{Ref/Note|Id=Point|Due to massively conflicting interpretations of this number, this page only lists the wording used in the original text of ''The Fall of Reach''.}} of the speed of light by the [[orbital defense platform]]s above [[Reach]].{{Ref/Novel|Id=FOR31|FOR|Chapter=31}} The MACs of {{UNSCShip|Infinity}} are additionally capable of firing various "sub-caliber" munitions for its massive twenty-seven metre bore, alongside some of the special types mentioned prior.{{Ref/Book|Id=HM132|HM|Section=Earth's Fleet|Page=132-133}} MACs generally have a range of 10,000 miles (16,093 kilometers).<ref name="ENC"/>


<gallery>
<gallery>
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===Usage===
===Usage===
[[File:HWG SecondBattleOfHarvest.png|thumb|250px|[[Battle Group X-Ray]] firing their MACs at a {{Pattern|Rasus|interdictor}}.]]
[[File:Outcome of Second Battle of Harvest.png|thumb|250px|[[Battle Group X-Ray]] firing their MACs at a {{Pattern|Rasus|interdictor}}.]]
{{Quote|MAC rounds? In atmosphere?|[[Jorge-052]] exclaiming his alarm at the intent to fire the MAC of {{UNSCShip|Grafton}} during the [[Fall of Reach]].}}
{{Quote|MAC rounds? In atmosphere?|[[Jorge-052]] exclaiming his alarm at the intent to fire the MAC of {{UNSCShip|Grafton}} during the [[Fall of Reach]].}}
{{Expand-section}}
{{Expand-section}}
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</gallery>
</gallery>


==MAC classifications==
==Types of MAC==
MACs operate under a complex designation scheme composed of three primary naming components;
*'''MAC model number''' - the serial number designation for the specific MAC in question, composed of six alphanumeric characters consisting of two digits followed by a letter, a digit, another letter, and a final digit. The model number refers to the entire MAC assembly; in smaller vessels this applies to just the singular gun, in larger vessels it may be used to refer to the entire MAC battery. When used to refer to a MAC battery as a whole, the individual guns appear not to have any individual designations. The precise method for naming MAC models is unclear and does not have any outwardly-obvious sequential numbering or correspondence to the target ship(s) in question.
**Example: ''45J3D3''
*'''Mark designation''' - Marks seem to be overall MAC generations, though the relationship of these weapons does not fully-line up with the years of introduction for the individual ships.
**Example: ''Mark IX''
*'''Size''' - this category denotes the overall size of the MAC, with the classifications of Light, Heavy, and Superheavy in use.{{Ref/Reuse|SuperMac}} The term "mini-MAC" is also sometimes informally used to designate [[naval autocannon]]s or [[Railgun (fiction)#Heavy railguns|heavy railguns]].
 
MACs are primarily divided into two distinct classifications; light MACs and heavy MACs (also referred to as Light Coil and Heavy Coil). Overall MAC generations are denoted as Marks, with specific models given a unique identifying code. Heavy MACs appear to be typically fitted on mainline fighting vessels such as those of the {{Class|Autumn|cruiser}} and {{Class|Strident|heavy frigate}}, while light MACs are predominantly fitted on lighter warships such as the ''Charon'' and ''Stalwart'' frigate classes, ships not intended as line warships such as the ''Epoch'' class carrier or ships historically considered under-gunned as capital ships, such as the {{Class|Halcyon|cruiser}}.
MACs are primarily divided into two distinct classifications; light MACs and heavy MACs (also referred to as Light Coil and Heavy Coil). Overall MAC generations are denoted as Marks, with specific models given a unique identifying code. Heavy MACs appear to be typically fitted on mainline fighting vessels such as those of the {{Class|Autumn|cruiser}} and {{Class|Strident|heavy frigate}}, while light MACs are predominantly fitted on lighter warships such as the ''Charon'' and ''Stalwart'' frigate classes, ships not intended as line warships such as the ''Epoch'' class carrier or ships historically considered under-gunned as capital ships, such as the {{Class|Halcyon|cruiser}}.


Some of the largest MAC types, such as those found on select orbital defense platforms and large warships, are referred to as "Super MACs".{{Ref/Reuse|FOR31}}{{Ref/Site|Id=SuperMac|URL=http://community.spartangames.co.uk/index.php?/topic/16805-halo-waypoint-update-with-spartan-new-ships/page-7|Site=Spartan Games Forums|Page=Halo Waypoint Update with Spartan - NEW SHIPS!|Detail=(defunct)|Quote='Super MAC' is more a category than a specific weapon. Many defense platforms do not have 'super MACs' as used by Reach installations, for example.}}
Some of the largest MAC types, such as those found on select orbital defense platforms and large warships, are referred to as "Super MACs".{{Ref/Reuse|FOR31}}{{Ref/Site|URL=http://community.spartangames.co.uk/index.php?/topic/16805-halo-waypoint-update-with-spartan-new-ships/page-7|Site=Spartan Games|Page=Halo Waypoint Update with Spartan - NEW SHIPS!|Detail=(defunct)|Quote='Super MAC' is more a category than a specific weapon. Many defense platforms do not have 'super MACs' as used by Reach installations, for example.}}
 
{| class="wikitable"|-
! Model !! Mark !! Size !! Usage !! Notes
|-
| 14B11R2 battery{{Ref/Book|Id=Mythos82|HM|Section=Under Siege|Page=82-83}} ||  || Light Coil{{Ref/Tabletop|HFB|Detail=Halberd-class destroyer in-game unit}} || {{Class|Halberd|light destroyer}}  || 1x 1411BR2 battery;{{Ref/Book|Id=Enc22Destroyers|Enc22|Page=124-225}} twin-linked 1170mm/647mm (46"/25.5") high-velocity coilguns.{{Ref/Reuse|Mythos82}} The larger gun is used for firing all standard munition packages, while the smaller is only used for firing kinetic rounds.{{Ref/Reuse|WF32}}
|-
|14D4A1 || Mark V || Superheavy coil || {{Class|Moncton|orbital weapon platform}}{{Ref/Book|Id=WF30|HWF|Section=Cairo Station|Page=30-31}} || Can accelerate multi-ton rounds to "several kilometres per second".{{Ref/Reuse|WF30}}
|-
| || Mark V || Superheavy coil{{Ref/Tabletop|HFB|Detail=UNSC MAC Platform in-game unit}} || {{Class|Erőd|orbital weapon platform}} || Capable of accelerating a 3,000 ton projectile to "point four-tenths"{{Ref/NoteReuse|Point}} of lightspeed.{{Ref/Reuse|FOR31}}
|-
| 22B6R3 battery{{Ref/Book|Id=Mythos70|HM|Section=Shield World|Page=70-71}} || || || {{Class|Phoenix|support ship}} {{C|refit}} || 3x individual  530cm 22B6R3 MACs{{Ref/Book|Id=WF48|HWF|Section=Spirit of Fire|Page=48-49}}{{Ref/Reuse|Mythos70}}
|-
| 20DA1C2 ||  || || {{Class|Gladius|heavy corvette}}{{Ref/Book|Id=Enc22Corvettes|Enc22|Page=128-129}} ||
|-
| 20F9B9 || || || {{Class|Point Blank|prowler}}{{Ref/Reuse|Enc22Corvettes}} ||
|-
| 45J3D3 || Mark IX || Heavy coil || {{Class|Autumn|heavy cruiser}}{{Ref/Book|Id=WF26|HWF|Section=Cruisers|Page=26-27}}{{Ref/Book|Id=Enc22Cruisers|Enc22|Page=119-120}} ||
|-
| 49F9A1 || || Heavy coil{{Ref/Tabletop|HFB|Detail=Marathon-class cruiser in-game unit}} || {{Class|Marathon|heavy cruiser}}{{Ref/Reuse|Enc22Cruisers}} ||
|-
| 50GE1A || || Heavy coil{{Ref/Tabletop|HFB|Detail=Valiant-class cruiser in-game unit}} || {{Class|Valiant|super-heavy cruiser}}{{Ref/Reuse|Enc22Cruisers}} ||
|-
| 56A2D4 || Mark II || Light coil || {{Class|Halcyon|light cruiser}}{{Ref/Reuse|Enc22Cruisers}}<br>{{Class|Stalwart|light frigate}}{{Ref/Site|Id=WaypointIAC|D=01|M=6|Y=2020|URL=https://www.halowaypoint.com/en-us/universe/vehicles/unsc-in-amber-clad|Site=Halo Waypoint|Page=In Amber Clad}}{{Ref/Book|Id=WF36|HWF|Section=In Amber Clad|Page=37-37}}{{Ref/Note|In the ''[[Halo Encyclopedia (2022 edition)]]'', this weapon is erroneously referred to as a 21X5V9 MAC. It is unclear whether this is an intentional retcon or indicative that UNSC ''In Amber Clad'' had a specialised weapon refit. As such, this page treats the ''Warfleet'' stat as definitive.}} || In the case of the refit ''Halcyon''-class cruiser ''{{UNSCShip|Pillar of Autumn}}'', the 56A2D4 runs two-thirds the length of the ship{{Ref/Book|Id=WF24|HWF|Section=Pillar of Autumn|Page=24-25}} and employed special magnetic field recyclers along its length that, when combined with booster capacitors, allowed the gun to fire three times in rapid succession.{{Ref/Reuse|FOR29}}{{Ref/Reuse|Enc22Cruisers}}
|-
| 56A2F9 || Mark II || Light coil || {{Class|Epoch|heavy carrier}} || Rapid-fire variant of the 56A2D4 model. On an ''Epoch'', this weapon is intended as a defensive weapon though it was sometimes employed to add to coordinated volleys of fire.{{Ref/Book|Id=WF40|HWF|Section=Carriers|Page=40-41}}{{Ref/Book|Id=Enc22Carriers|Enc22|Page=126-127}}
|-
| 5D7C2 || || || {{Class|Lancer|fast-attack corvette}} || 1x 5D7C2{{Ref/Site|Id=CFFoundations|URL=https://www.halowaypoint.com/news/canon-fodder-foundations|Site=Halo Waypoint|Page=Canon Fodder - Foundations|D=12|M=01|Y=2022}}
|-
| 5D8F6 || || || {{Class|Able|heavy destroyer}} || The 5D8F6 was not standard on the original 2490 version and only became standard with the 2525 refit. Despite this, at least one Able, the {{UNSCShip|Gorgon}} was refit with a MAC sometime in the 2490's{{Ref/Site|Id=CFDigsite|URL=https://www.halowaypoint.com/news/canon-fodder-digsite-dissection|Site=Halo Waypoint|Page=Canon Fodder - Digsite Dissection|D=28|M=07|Y=2023}}
|-
| 65P8V1 || || Light coil{{Ref/Tabletop|HFB|Detail=Paris-class frigate in-game unit}} || {{Class|Paris|heavy frigate}} || 1x 65P8V1 MAC{{Ref/Book|Id=Enc22Frigates|Enc22|Page=120-123}}
|-
| 76G3V5 battery || Mark X || Superheavy coil || {{Class|Vindication|light battleship}} || 1x 76G3V5 MAC battery; twin Mark X superheavy MACs{{Ref/Reuse|Enc22Destroyers}}
|-
| 83B6R1 || || || {{Class|Hillsborough|heavy destroyer}}{{Ref/Reuse|Enc22Destroyers}} ||
|-
| 83B6R3 || Mark II || Light coil || {{Class|Charon|light frigate}} || 1x 83B6R3 MAC{{Ref/Site|Id=Bulletin101012|URL=http://blogs.halowaypoint.com/Headlines/post/2012/10/10/The-Halo-Bulletin-101012-.aspx|Site=Halo Waypoint|Page=The Halo Bulletin: 10.10.12|D=02|M=03|Y=2013}}{{Ref/Book|Id=H4EVG191|H4EVG|Page=191-192}}{{Ref/Reuse|Enc22Frigates}}
|-
| 90C1E1 || || Heavy coil || {{Class|Orion|assault carrier}} || 2x 90C1E1 MACs{{Ref/Reuse|Enc22Carriers}}
|-
| 94B1E6 || Mark IV || Heavy coil || {{Class|Strident|heavy frigate}}{{Ref/Site|Id=WaypointFrigate|D=01|M=6|Y=2020|URL=https://www.halowaypoint.com/en-us/universe/vehicles/unsc-frigate|Site=Halo Waypoint|Page=UNSC Frigate}} || Limited munitions supply, twelve capacitor banks for power.{{Ref/Book|Id=WF38|HWF|Section=Frigates|Page=38-39}}{{Ref/Reuse|Enc22Frigates}}
|-
| CR-01D || Series 6 || Superheavy coil{{Ref/Tabletop|HFB|Detail=Punic-class supercarrier in-game unit}} || {{Class|Punic|supercarrier}} || 2x CR-01D Series 6 MAC{{Ref/Reuse|Enc22Carriers}}
|-
| CR-03 || Series 8 || || {{Class|Infinity|supercarrier}} || Initial model also known as the '''CR03S8 MAC'''. Fielded on {{UNSCShip|Infinity}}, these guns have a twenty-seven metre bore.{{Ref/Reuse|HM132}}
|-
| CR-03B || Series 8 || Superheavy || {{Class|Infinity|supercarrier}}{{Ref/Reuse|Enc22Carriers}} || Refit package model integrated late in [[2558]], though originally intended for the ''Eternity''.{{Ref/Reuse|WF42}}
|}


===Mark II===
The Mark II MAC is a light coil system, with its variants found on the ''Charon'' and ''Stalwart'' frigate classifications, alongside the ''Epoch''-class carrier and refit ''Halcyon''-class cruiser.
*'''Mark II, Light Coil - 56A2D4/MAC''' - Employed on the {{Class|Stalwart|light frigate}} {{UNSCShip|In Amber Clad}}{{Ref/Site|Id=WaypointIAC|D=01|M=6|Y=2020|URL=https://www.halowaypoint.com/en-us/universe/vehicles/unsc-in-amber-clad|Site=Halo Waypoint|Page=In Amber Clad}}{{Ref/Book|Id=WF36|HWF|Section=In Amber Clad|Page=37-37}} and post-refit ''Halcyon''-class cruiser {{UNSCShip|Pillar of Autumn}}.{{Ref/Book|Id=WF24|HWF|Section=Pillar of Autumn|Page=24-25}} On the ''Stalwart''-class frigate, the gun is stored in the lower boom of the ship while the gun's pulsed power-storage and fire-control systems are stored in the upper hull.{{Ref/Reuse|WF36}} In the case of the refit ''Pillar of Autumn'', the 56A2D4 runs two-thirds the length of the ship{{Ref/Reuse|WF24}} and employed special magnetic field recyclers along its length, that when combined with booster capacitors allowed the gun to fire three times in rapid succession.{{Ref/Reuse|FOR29}}
*'''Mark II, Light Coil - 52A6F9/MAC''' - Employed on the {{Class|Epoch|heavy carrier}}, this system is a rapid-fire variant of the 52A6D4 model. On an ''Epoch'', this weapon is intended as a defensive weapon though it was sometimes employed to add to coordinated volleys of fire.{{Ref/Book|Id=WF40|HWF|Section=Carriers|Page=40-41}}
*'''Mark II, Light Coil - 83B6R3/MAC''' - Employed on the {{Class|Charon|light frigate}} {{UNSCShip|Forward Unto Dawn}}.{{Ref/Site|Id=Bulletin101012|D=10|M=10|Y=2014|URL=http://blogs.halowaypoint.com/Headlines/post/2012/10/10/The-Halo-Bulletin-101012-.aspx|Site=Halo Waypoint|Page=The Halo Bulletin: 10.10.12|Detail=(defunct, [https://web.archive.org/web/20130302031735/http://blogs.halowaypoint.com/Headlines/post/2012/10/10/The-Halo-Bulletin-101012-.aspx Archive])}}{{Ref/Book|Id=H4EVG191|H4EVG|Page=191-192}}
<gallery>
<gallery>
File:HW - MII Light coil 56A2D4 MAC.png|The 56A2D4 in the ''Pillar of Autumn''.
File:HW - MII Light coil 56A2D4 MAC.png|The 56A2D4 in the ''Pillar of Autumn''.
File:HW - MII Light coil 56A2D4 MAC2.png|The 56A2D4 in the ''In Amber Clad''.
File:HW - MII Light coil 56A2D4 MAC2.png|The 56A2D4 in the ''In Amber Clad''.
</gallery>
===Mark IV===
The Mark IV MAC is installed on the {{Class|Strident|heavy frigate}}.
*'''Mark IV, Heavy Coil - 94B1E6/MAC''' - The 94B1E6 heavy MAC has twelve massive capacitor banks, allowing the ''Strident'' class firepower comparable to destroyers and light cruisers. This gun's limitation comes in the limited ammo supply carried aboard the ship.{{Ref/Book|Id=WF38|HWF|Section=Frigates|Page=38-39}}{{Ref/Site|Id=WaypointFrigate|D=01|M=6|Y=2020|URL=https://www.halowaypoint.com/en-us/universe/vehicles/unsc-frigate|Site=Halo Waypoint|Page=UNSC Frigate}}
===Mark V===
The Mark V MAC is part of the "Super MAC" classification of MAC. This MAC is the central armament of the [[Erőd-class orbital weapon platform|orbital defense guns]] stationed over [[Reach]] in [[2552]]{{Ref/Reuse|FOR31}} and the {{Class|Moncton|orbital weapon platform}} over [[Earth]].{{Ref/Book|Id=WF30|HWF|Section=Cairo Station|Page=30-31}} The Mark V Superheavy MACs found over Reach were capable of accelerating a 3,000 ton projectile to "point four-tenths"{{Ref/Reuse|Point}} of lightspeed.{{Ref/Reuse|FOR31}}
*'''Mark V, 14D4A1 MAC''' - Employed on the ''Moncton'' orbital defense platform, such as [[Cairo Station (station)|Cairo Station]]. This gun can accelerate multi-ton rounds to "several kilometres per second".{{Ref/Reuse|WF30}}
<gallery>
File:HW 14D4A1 MAC internals.png|Internal workings of the 14D4A1 MAC on ''[[Cairo Station (station)|Cairo Station]]''.
File:HW 14D4A1 MAC internals.png|Internal workings of the 14D4A1 MAC on ''[[Cairo Station (station)|Cairo Station]]''.
File:HW CR-03B MAC.png|The forward CR-03B MAC's on the Infinity.
</gallery>
 
===Mark IX===
The Mark IX is a heavy MAC fitted on the {{Class|Autumn|heavy cruiser}}.
*'''Mark IX, Heavy Coil - 45J3D3/MAC''' - fitted onto the ''Autumn''-class cruiser.{{Ref/Reuse|H4EVG191}}{{Ref/Book|Id=WF26|HWF|Section=Cruisers|Page=26-27}}
 
===Series 8===
The Series 8 MACs are fitted onto the {{Class|Infinity|supercarrier}} - namely the lead ship of the class. Series 8s were intended for inclusion on the {{UNSCShip|Eternity}}, though the weapons were since installed on ''Infinity'' as an upgrade package.
*'''CR-03 Series 8 MAC''' - Initial model also known as the '''CR03S8 MAC'''. Fielded on {{UNSCShip|Infinity}}, these guns have a twenty-seven metre bore.{{Ref/Reuse|HM132}}
*'''CR-03B Series 8 MAC''' - Refit package model integrated late in [[2558]], though originally intended for the ''Eternity''.{{Ref/Reuse|WF42}}
<gallery>
File:HW CR-03B MAC.png|Four CR-03B MAC's on the Infinity.
</gallery>
</gallery>


===MAC batteries===
===MAC batteries===
"MAC batteries" refer to weapon systems in which multiple MACs are linked together as part of one weapon system. Such batteries may use differing bores and barrel lengths for different usage scenarios, or may consist of multiple identical guns.
"MAC batteries" refer to weapon systems in which multiple MACs are linked together as part of one weapon system. Such batteries may use differing bores and barrel lengths for different usage scenarios, or may consist of multiple identical guns.
*'''14B11R2 MAC battery''' - the dual MACs employed aboard the {{Class|Halberd|light destroyer}}, consisting of twin-linked 1170mm/647mm MACs.{{Ref/Book|Id=Mythos82|HM|Section=Under Siege|Page=82-83}} The larger gun is used for firing all standard munition packages, while the smaller is only used for firing kinetic rounds.{{Ref/Reuse|WF32}}
*'''22B6R3 MAC battery'''{{Ref/Book|Id=Mythos70|HM|Section=Shield World|Page=70-71}} - consisting of three eponymous 530 cm 22B6R3 MACs{{Ref/Book|Id=WF48|HWF|Section=Spirit of Fire|Page=48-49}} , this battery was employed in the military refit module attached to the {{Class|Phoenix|colony ship}} ''Spirit of Fire''.{{Ref/Reuse|Mythos70}}


==Usage==
==Usage==
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[[UNSC frigate]]s typically run the length of the entire ship, averaging a length of {{Convert|183|m|ft}}.{{Ref/Reuse|EVG114}} Frigates in the [[Human-Covenant War]] typically employed light MACs. The ''Stalwart'' and ''Charon''-classes equipped a 56A2D4 Light Coil MAC and an 83B6R3 Light Coil MAC, respectively, with the post-war ''Strident'' heavy frigate equipped with a Mark IV 94B1E6 heavy coil MAC.{{Ref/Reuse|WF38}} Despite being a heavy frigate, the ''Paris''-class employed a light MAC.{{Ref/Reuse|HFB93}}
[[UNSC frigate]]s typically run the length of the entire ship, averaging a length of {{Convert|183|m|ft}}.{{Ref/Reuse|EVG114}} Frigates in the [[Human-Covenant War]] typically employed light MACs. The ''Stalwart'' and ''Charon''-classes equipped a 56A2D4 Light Coil MAC and an 83B6R3 Light Coil MAC, respectively, with the post-war ''Strident'' heavy frigate equipped with a Mark IV 94B1E6 heavy coil MAC.{{Ref/Reuse|WF38}} Despite being a heavy frigate, the ''Paris''-class employed a light MAC.{{Ref/Reuse|HFB93}}


On the ''Paris'' and ''Charon''-classes of ship, the barrel of the gun itself is located in the upper boom at the fore of the ship, with the lower boom containing fire-control systems and pulsed power storage. This is inverted on the ''Stalwart'' class, where the barrel is in the lower boom.{{Ref/Reuse|WF36}} The heavy MAC employed by the ''Strident'' frigate employs twelve capacitor cells, allowing it to achieve firepower levels similar to those of destroyers or light cruisers - limited only by the stock of ammunition carried aboard ship.{{Ref/Reuse|WF38}}
On the ''Paris'' and ''Charon''-classes of ship, the barrel of the gun itself is located in the upper boom at the fore of the ship, with the lower boom containing fire-control systems and pulsed power storage. This is inverted on the ''Stalwart'' class, where the barrel is in the lower boom.{{Ref/Reuse|WF36}} The post-war {{Class|Anlace|light frigate}} is a unique exception to the typical rule of spinally-mounted MACs, instead employing a single MAC on a rotating turret on the ship's aft, allowing the gun to fire at targets around the ship.{{Ref/Generic|Id=Loftus1|[[Stephen Loftus]] on the Anlace-class frigate [[Talk:Anlace-class frigate|talk page]]}} The heavy MAC employed by the ''Strident'' frigate employs twelve capacitor cells, allowing it to achieve firepower levels similar to those of destroyers or light cruisers - limited only by the stock of ammunition carried aboard ship.{{Ref/Reuse|WF38}}


===Destroyer MACs===
===Destroyer MACs===
The [[Unidentified UNSC heavy destroyer class|heavy destroyer]] {{UNSCShip|Gorgon}} was the first ship of its class to mount a MAC, sporting one gun and carrying only three slugs.{{Ref/Anthology|Id=Cole|HEvo|Story=The Impossible Life and the Possible Death of Preston J. Cole}} The later ''Halberd''-class was fitted with a 14B11R2 MAC battery consisting of dual twin-linked 1170mm/647mm MACs, with the smaller gun only used for launching kinetic kill rounds and the larger gun compatible with all standard mission packages.{{Ref/Reuse|WF32}}{{Ref/Reuse|Mythos82}} The ''Halberd'' is able to fire its MACs on lower-than 100% charge levels for more rapid-firing,{{Ref/Reuse|FOR17}} and can be equipped with MAC capacitor cells to easily recharge; these cells are easily replacable when damaged.{{Ref/Reuse|WF32}}
The [[UNSC heavy destroyer|heavy destroyer]] {{UNSCShip|Gorgon}} was the ship of its class to mount a MAC, sporting one gun and carrying only three slugs.{{Ref/Anthology|Id=Cole|HEvo|Story=The Impossible Life and the Possible Death of Preston J. Cole}} The later ''Halberd''-class was fitted with a 14B11R2 MAC battery consisting of dual twin-linked 1170mm/647mm MACs, with the smaller gun only used for launching kinetic kill rounds and the larger gun compatible with all standard mission packages.{{Ref/Reuse|WF32}}{{Ref/Reuse|Mythos82}} The ''Halberd'' is able to fire its MACs on lower-than 100% charge levels for more rapid-firing{{Ref/Reuse|FOR17}}, and can be equipped with MAC capacitor cells to easily recharge; these cells are easily replacable when damaged.{{Ref/Reuse|WF32}}


Destroyers like the ''Halberd'' are typically organised into wolf-packs, aiming to coordinate MAC volleys on enemy ships and overwhelm their defenses.{{Ref/Reuse|WF32}}
Destroyers like the ''Halberd'' are typically organised into wolf-packs, aiming to coordinate MAC volleys on enemy ships and overwhelm their defenses.{{Ref/Reuse|WF32}}


===Cruiser MACs===
===Cruiser MACs===
Unlike their smaller counterparts, [[cruiser]]s typically employ Heavy MACs as a standard armament - befitting of their status as the primary line warship of the UNSC Navy. The {{Class|Marathon|heavy cruiser}} sports two heavy MACs{{Ref/Book|EVG|Page=42}}{{Ref/Book|Id=HFB93|Halo: Fleet Battles core rulebook|Page=93}} Late-war ''Marathons'' were in such high demand that even half-completed hulls were pressed into service for the use of their heavy MAC systems, often paired together with another ''Marathon'' as part of the [[UNSC Navy tactical formations|"Gorgon"]] formation. These cruisers would pinpoint larger Covenant warships with sustained fire, giving smaller craft a chance to deal damage of their own.{{Ref/Book|Id=HFB125|Halo: Fleet Battles core rulebook|Page=125}}The ''Autumn''-class heavy cruiser was fitted with a Mark IX heavy coil 45J3D3 MAC, and the {{Class|Valiant|super-heavy cruiser}} a heavy MAC of its own.{{Ref/Game|Halo: Fleet Battles|Valiant-class cruiser expansion}}
Unlike their smaller counterparts, [[cruiser]]s typically employ Heavy MACs as a standard armament - befitting of their status as the primary line warship of the UNSC Navy. The {{Class|Marathon|heavy cruiser}} sports two heavy MACs{{Ref/Book|EVG|Page=42}}{{Ref/Book|Id=HFB93|Halo: Fleet Battles|Detail=Core Rulebook|Page=93}} Late-war ''Marathons'' were in such high demand that even half-completed hulls were pressed into service for the use of their heavy MAC systems, often paired together with another ''Marathon'' as part of the [[UNSC Navy tactical formations|"Gorgon"]] formation. These cruisers would pinpoint larger Covenant warships with sustained fire, giving smaller craft a chance to deal damage of their own.{{Ref/Book|Id=HFB125|Halo: Fleet Battles|Detail=Core Rulebook|Page=125}}The ''Autumn''-class heavy cruiser was fitted with a Mark IX heavy coil 45J3D3 MAC, and the {{Class|Valiant|super-heavy cruiser}} a heavy MAC of its own.{{Ref/Game|Halo: Fleet Battles|Valiant-class cruiser expansion}}


Contrary to the aforementioned examples, the ''Halcyon''-class light cruiser does not employ a heavy MAC, but rather a light one - likely the cause of the ship being infamous for being undergunned within the UNSC fleet. When refit for [[Operation: RED FLAG]], the ''Pillar of Autumn'' was fitted with a specialised modification to a Mark II light coil 56A2D4 MAC - the same as that found on the ''Stalwart''-class light frigate.{{Ref/Reuse|WF24}} This gun ran two-thirds the length of the ''Autumn''{{'}}s length,{{Ref/Reuse|WF24}} and employed special magnetic field recyclers that - when combined with booster capacitors - allowed the gun to fire three times in rapid succession.{{Ref/Reuse|FOR29}}
Contrary to the aforementioned examples, the ''Halcyon''-class light cruiser does not employ a heavy MAC, but rather a light one - likely the cause of the ship being infamous for being undergunned within the UNSC fleet. When refit for [[Operation: RED FLAG]], the ''Pillar of Autumn'' was fitted with a specialised modification to a Mark II light coil 56A2D4 MAC - the same as that found on the ''Stalwart''-class light frigate.{{Ref/Reuse|WF24}} This gun ran two-thirds the length of the ''Autumn''{{'}}s length{{Ref/Reuse|WF24}}, and employed special magnetic field recyclers that - when combined with booster capacitors - allowed the gun to fire three times in rapid succession.{{Ref/Reuse|FOR29}}


===Carrier MACs===
===Carrier MACs===
[[UNSC carrier]]s employ a range of MAC types. On the smaller end, the ''Epoch''-class employs the Mark II 52A6F9 light coil MAC, a rapid-fire upgrade of that seen on the ''Stalwart''-class Frigate and intended for defensive purposes. In larger fleets, the ''Epoch'' may lend this MAC's fire to coordinated volleys. The {{Class|Orion|assault carrier}} employs a larger heavy MAC,{{Ref/Game|Halo: Fleet Battles|Orion-class cruiser expansion}} while the extremely large {{Class|Punic|supercarrier}} employs two "Super-MACs", running the length of its enormous spaceframe. In addition to this, the ''Punic'' sports a number of smaller "Mini-MAC" turrets allowing it to fire on all angles.{{Ref/Site|Id=SpartanPunic|URL=http://www.spartangames.co.uk/meet-the-big-hitters|Site=Spartan Games|Page=Meet The Big Hitters|D=01|M=6|Y=2016}}
[[UNSC carrier]]s employ a range of MAC types. On the smaller end, the ''Epoch''-class employs the Mark II 52A6F9 light coil MAC, a rapid-fire upgrade of that seen on the ''Stalwart''-class Frigate and intended for defensive purposes. In larger fleets, the ''Epoch'' may lend this MAC's fire to coordinated volleys. The {{Class|Orion|assault carrier}} employs a larger heavy MAC{{Ref/Game|Halo: Fleet Battles|Orion-class cruiser expansion}}, while the extremely large {{Class|Punic|supercarrier}} employs two "Super-MACs", running the length of its enormous spaceframe. In addition to this, the ''Punic'' sports a number of smaller "Mini-MAC" turrets allowing it to fire on all angles.{{Ref/Site|Id=SpartanPunic|URL=http://www.spartangames.co.uk/meet-the-big-hitters|Site=Spartan Games|Page=Meet The Big Hitters|D=01|M=6|Y=2016}}


===Orbital defense platform MACs===
===Orbital defense platform MACs===
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==="Mini"-MACs===
==="Mini"-MACs===
The so-called "Mini"-MAC is a nickname given to the primary weapon system employed by the ground-based [[M510 Mammoth]] siegework platform. The Mammoth sports a Mark 2457/35&nbsp;cm HRG, a large [[Railgun (fiction)|railgun]] intended to target and eliminate hostile vessels, vehicles, and fortifications in terrestrial or suborbital positions.{{Ref/Book|Id=H4EVG115|H4EVG|Page=115}}{{Ref/Generic|Id=H4IGMammoth|[[Halo 4 Interactive Guide]]|Mammoth}} These weapons can be linked to a target locator, and are powerful enough to take out even [[Forerunner]] [[Z-8060 particle cannon]]s.{{Ref/Level|Id=H4Reclaimer|H4|Reclaimer (level)|Reclaimer}}  
The so-called "Mini"-MAC is a nickname given to the primary weapon system employed by the ground-based [[M510 Mammoth]] siegework platform. The Mammoth sports a Mark 2457/35 cm HRG{{Ref/Note|Presumably, HRG stands for Heavy Railgun}}, a large [[railgun]] intended target and eliminate hostile vessels, vehicles and fortifications in terrestrial or suborbital positions.{{Ref/Book|Id=H4EVG115|H4EVG|Page=115}}{{Ref/Generic|Id=H4IGMammoth|[[Halo 4 Interactive Guide]]|Mammoth}} These weapons can be linked to a target locator, and are powerful enough to take out even [[Forerunner]] [[Z-8060 particle cannon]]s.{{Ref/Level|Id=H4Reclaimer|H4|Reclaimer (level)|Reclaimer}}  


A number of Mini MAC turrets serve as secondary armaments on the ''Punic''-class supercarrier.{{Ref/Reuse|SpartanPunic}}
A number of Mini MAC turrets serve as secondary armaments on the ''Punic''-class supercarrier.{{Ref/Reuse|SpartanPunic}}


==="Onagers"===
==="Onagers"===
[[File:Onager.jpg|thumb|200px|An Onager MAC on [[Reach]] in the [[Asźod ship breaking yards]].]]
[[File:Onager.jpg|thumb|200px|right|An Onager MAC on [[Reach]] in the [[Asźod ship breaking yards]].]]
{{Main|Mark 2488 Magnetic Accelerator Cannon|Mark 2551 Magnetic Accelerator Cannon}}
{{Main|Mark 2488 Magnetic Accelerator Cannon|Mark 2551 Magnetic Accelerator Cannon}}
The Mark 2488 Magnetic Accelerator Cannon, informally known as the Onager, is a relatively small Magnetic Accelerator Cannon used for static defense. A manned version was used to defend the ''Pillar of Autumn'' on Reach.{{Ref/Level|HR|The Pillar of Autumn (Halo: Reach level)|The Pillar of Autumn}} The Mark 2488 fires a 15&nbsp;cm round with up to 1.1 gigajoules (0.25 tons) of kinetic energy. It is 32.6 meters long,{{Ref/Book|H4EVG|Page=75}}
The Mark 2488 Magnetic Accelerator Cannon, informally known as the Onager, is a relatively small Magnetic Accelerator Cannon used for static defense. A manned version was used to defend the ''Pillar of Autumn'' on Reach.{{Ref/Level|HR|The Pillar of Autumn (Halo: Reach level)|The Pillar of Autumn}} The Mark 2488 fires a 15 cm round with up to 1.1 gigajoules (0.25 tons) of kinetic energy. It is 32.6 meters long,{{Ref/Book|H4EVG|Page=75}}


==Related technologies==
==Related technologies==
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==Gameplay==
==Gameplay==
[[File:HW MACBlast HUD.jpg|thumb|The MAC Blast in use.]]
[[File:HW MACBlast HUD.jpg|thumb|right|The MAC Blast in use.]]
===''Halo Wars''===
===''Halo Wars''===
{{Quote|Use the Spirit of Fire's awesome Mass Accelerator Cannon to incinerate enemy troops.|In-game description.}}
{{Quote|Use the Spirit of Fire's awesome Mass Accelerator Cannon to incinerate enemy troops.|In-game description.}}
Line 202: Line 175:
File:H4-Infinity-Firing.jpg|The {{UNSCShip|Infinity}} fires her forward MACs at the ''[[Mantle's Approach]]''.
File:H4-Infinity-Firing.jpg|The {{UNSCShip|Infinity}} fires her forward MACs at the ''[[Mantle's Approach]]''.
File:Corvette destroyed.png|The effect of a MAC round fired from an orbital defense platform on an {{Pattern|Ceudar|heavy corvette}}.
File:Corvette destroyed.png|The effect of a MAC round fired from an orbital defense platform on an {{Pattern|Ceudar|heavy corvette}}.
File:HW Screenshots E3 11.jpg|A MAC round impacting the surface of [[Harvest]].
File:MAC - Bombardment.jpg|A MAC round impacting the surface of [[Harvest]].
File:TFoR AS - Commonwealth MAC.jpg|{{UNSCShip|Commonwealth}} firing her MAC.
File:TFoR AS - Commonwealth MAC.jpg|{{UNSCShip|Commonwealth}} firing her MAC.
File:H5G Anlace-class Frigate.jpg|An ''Anlace''-class frigate, lacking the traditional spiral mount, instead sports a downsized variant of the MAC atop its hull.
File:H2A Screenshot Cairo MAC Slug Rear.png|thumb|The rear of a slug for ''[[Cairo Station (station)|Cairo Station]]''{{'}}s Magnetic Accelerator cannon, seen in ''[[Halo 2: Anniversary]]''.
File:H2A Screenshot Cairo MAC Slug Rear.png|thumb|The rear of a slug for ''[[Cairo Station (station)|Cairo Station]]''{{'}}s Magnetic Accelerator cannon, seen in ''[[Halo 2: Anniversary]]''.
File:H2A Screenshot Cairo MAC Slug Tip.png|thumb|The tip of a slug for ''[[Cairo Station (station)|Cairo Station]]''{{'}}s Magnetic Accelerator cannon.  
File:H2A Screenshot Cairo MAC Slug Tip.png|thumb|The tip of a slug for ''[[Cairo Station (station)|Cairo Station]]''{{'}}s Magnetic Accelerator cannon.  

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