Editing Mark 2488 Onager

{{Status|Canon}}
{{Weapon infobox
|image=[[File:HReach-OnagerMDC.png|300px]]
|name=Mark 2488 Magnetic Accelerator Cannon 
|manufacturer=[[Misriah Armory]]
|model=Mk/2488
|type=Magnetic Accelerator Cannon
|cost=
|length={{Convert|106.9|ft|m|sp=us|disp=flip}}{{Ref/Book|Id=Enc22|Enc22|Page=182}}
|width={{Convert|46.2|ft|m|sp=us|disp=flip}}{{Ref/Reuse|Enc22}}
|height={{Convert|33|ft|m|sp=us|disp=flip}}{{Ref/Reuse|Enc22}}
|weight=93.4 tonnes (103 tons){{Ref/Reuse|Enc22}}
|damage per hit=
|magazine=
|maxammo=
|fire=
|ammotype=15 cm M895 HV/FTHPP (1.1 gigajoules per hit){{Ref/Reuse|Enc22}}<ref name="vis">'''[[Halo: The Essential Visual Guide]]''', ''page 114''</ref>
|operation=[[Wikipedia:Coilgun|Electromagnetic linear motor]]
|rate=20 rounds a minute
|velocity=High
|optics=
|range=Long
|service=[[Human-Covenant War]]
|affiliation=United Nations Space Command
}}
The '''Mark 2488 Magnetic Accelerator Cannon''', formally designated '''15&nbsp;cm Mark/2488 1.1GJ MAC''', also known as the '''Onager''' and often referred to as a "'''[[mass driver]]'''", is a stationary [[Magnetic Accelerator Cannon]] used by the [[United Nations Space Command]] during the [[Human-Covenant War]].<ref name="stats">'''[[Bungie.net]]''' ''Halo: Reach'' game stats</ref>

The [[Mark 2551 Magnetic Accelerator Cannon|Mark 2551/25cm Portable]] is an upgraded variant of the weapon brought into service after the war.

==Design details==
The Onager is capable of firing a 15&nbsp;cm ferric-tungsten hollow-point round with up to 1.1 gigajoules of kinetic energy.{{Ref/Reuse|stats}} It has five linearly arranged magnetic coils, each of which needs to charge individually before each shot. The weapon needs to cool off after every shot, and does so by opening a radial vent on the upper portion of the barrel. The weapon is operated from a small booth on the left side of the cannon.{{Ref/Reuse|reach}}

==Operational history==
During the [[Fall of Reach]], a group of [[UNSC Marine Corps|UNSC Marines]] installed an Onager on top of one of the planet's [[Asźod ship breaking yards|ship-breaking facilities]] in [[Asźod]] to protect the drydocked {{UNSCShip|Pillar of Autumn}}. [[Emile-A239]] manned the mass driver to fend off incoming Covenant [[Type-26 Ground Support Aircraft|Banshees]] and [[Kez'katu-pattern Phantom|Phantoms]] before the ''Autumn'' could take off.<ref name="reach">'''Halo: Reach''', campaign level ''[[The Pillar of Autumn (Halo: Reach level)|The Pillar of Autumn]]''</ref> However, the Spartan was killed by a [[Sangheili Zealot]], prompting [[SPARTAN-B312]] to commandeer the cannon and successfully delay the Covenant assault on the ''Autumn'' by crippling an incoming {{Class|CCS|battlecruiser}} with a shot to its ventral [[energy projector]].{{Ref/Reuse|reach}}

==Trivia==
*The Onager is named after a [[Wikipedia:Onager (siege weapon)|medieval siege weapon]], which in turn takes its name from a [[Wikipedia:Onager|horse species]].
*On the ''Bungie.net'' weapons statistics page, the description for the Onager is simply "I need a weapon", a reference to a line by [[John-117]] in the opening cinematic of the level ''[[Cairo Station]]'' in ''[[Halo 2]]''.
*"S-239" is painted on the Onager's frame. This is a reference to [[Emile-A239]], who was killed while operating the weapon. Also, "S-266" is painted on the left side. That is a reference to [[Jun-A266]].
*The "[[using Onager early]]" glitch can be exploited so that a player can reach the driver before the scripted cutscene. This glitch can provide a player with an easy killing spree by shooting down [[Banshees]], or avoiding enemy lances by shooting the Phantoms carrying them.

==Gallery==
<gallery>
File:HR_Onager_Early_Concept.jpg|An early concept for the Onager by [[Isaac Hannaford]].
File:HR_Onager_Concept.jpg|The cannon's final design.
File:HaloReach - Mass Driver Cannon.jpg|A first-person view of the Onager.
File:Onager.jpg|The Onager installed in the Asźod ship breaking yards.
File:HaloReach - MACrusher.jpg|The Onager, manned by SPARTAN-B312, firing a round at the incoming Covenant ''CCS''-class battlecruiser.
File:HReach-PillarOfAutumn-MDC.jpg|The Onager discharging a ferric-tungsten slug at the Covenant ''CCS''-class battlecruiser.
File:Onager_charging.jpg|An Onager's electromagnetic coils charging before it fires.
File:Onager_controls.jpg|The control booth of an Onager cannon.
File:Onager.png|A blueprint for the Onager.
</gallery>

==List of appearances==
*''[[Halo: Reach]]'' {{1st}}

==Sources==
{{Ref/Sources}}

{{UNSC heavy weapons}}
[[Category:Magnetic acceleration weapons]]
[[Category:Artillery]]
[[Category:UNSC ground weapons]]