Point-defense gun

A point-defense gun is a type of United Nations Space Command starship-mounted magnetic accelerator weapon. Though several models exist, the most common type of point-defense gun fires 50mm high-explosive projectiles.

Functionality
The point-defense gun fills a role similar to the CIWS designs created during the 20th century. Based around magnetic linear accelerator technology, it fires 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. They are instead meant to intercept smaller threats like Seraph fighters or boarding craft to prevent (or at least lessen) the damage inflicted to 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" AIs seem better able to operate the point-defense guns than standard computers and also lesser "dumb" AIs.

Operational history
Point-defense guns have been standard armament on UNSC vessels since the Insurrection, a common model being the M810 Helix. Later, s used a dual-barreled point-defense weapon system designated as the M910 Rampart point defense network.

During the human occupation of Installation 04, the ODSTs that recaptured and secured the wreckage of the from the Covenant managed to scavenge several of the ship's 50mm turrets. The ODSTs utilized the scavenged defense weapons and used them as anti-air defensive emplacements at Alpha Base.

Known types

 * M606 Goalkeeper point defense gun – Used on orbital defense platforms.
 * M710 Bulwark point defense gun – Used on s.
 * M800 point defense gun – Used on refitted s.
 * M810 Helix point defense gun – Used on s, s, and UNSC heavy destroyers.
 * M870 Rampart point defense gun – Used on s, s, s, s, s, and s.
 * M910 Rampart point defense network – Used on s, s, and s.
 * M965 Fortress point defense network – Used on.
 * Mark 57 Arena point defense gun – Used on s.

List of appearances

 * Halo: The Fall of Reach
 * Halo: The Flood
 * Halo 3
 * Halo 3: ODST
 * Halo Legends
 * Origins
 * Halo: Evolutions - Essential Tales of the Halo Universe
 * The Impossible Life and the Possible Death of Preston J. Cole
 * Halo: Reach
 * Halo: Combat Evolved Anniversary
 * Halo 4
 * Spartan Ops
 * Halo: Fractures
 * Breaking Strain
 * Halo: Envoy