Halo Alpha
Halo Alpha

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The Point-defense gun is a United Nations Space Command starship-mounted weapon that fires 50mm high-explosive projectiles.[3]

Design details[]


The Point-Defense Gun functions much like the CIWS designs created during the 20th Century, firing 50mm projectiles. Unlike Archer missiles and the MAC weapon systems mounted on capital ships, the Point-Defense Guns are not used to engage Covenant capital ships in ship-to-ship combat (The only known case is in Halo: Reach level Long Night Of Solace), but is instead meant to take out smaller threats like Seraph fighters[4] or boarding craft to prevent (or at least lessen) the damage inflicted on a warship.

Because human operators lack the reflexive responses necessary to operate the point-defense guns to maximum effect, the autocannons are computer controlled and, if an AI is available, control is diverted to it. "Smart" AI's seem better able to operate the Point-Defense Guns than standard computers and also lesser "dumb" AI's.[2]

In Halo: Reach Point-Defense Guns can kill a player with a single shot if it hits the player.

Operational history[]

During the human occupation of Installation 04, the ODSTs that recaptured and secured the wreckage of UNSC Pillar of Autumn from the Covenant managed to scavenge[5] several dual barreled[3] 50mm turrets. The ODSTs utilised the scavenged defense weapons and used them as anti-air defensive emplacements at Alpha Base.


  • M870 Rampart 50mm Point Defense Guns - lower and narrower in profile than the M910, it was mounted on Charon-class light frigates.[6]
  • M965 Fortress Point Defense Guns - Prototype 70mm guns mounted onboard UNSC Infinity
  • M910 point defense network - Used on UNSC Pillar of Autumn, Autumn-class heavy cruisers and Paris-class heavy frigates.