M71 Scythe

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The M71 Anti-Aircraft Gun, nicknamed the Scythe, is a stationary rotary cannon emplacement used by the UNSC Armed Forces. It is produced by Misriah Armory.

Design
The M71 Scythe is a powerful pneumatically powered, air-cooled anti-aircraft weapon that performs reliably against many hostile aircraft. It is specifically designed to fire the powerful 20x102mm high-explosive incendiary/armor piercing cartridge from a 100,000-round drum; using its six barrels, the Scythe can fire at a rate of 6,000 rounds per minute, though some Scythes are fed by 1,000-round drums and consequently maintain lower rates of fire. This high rate of fire allows the Scythe to strip away the armor of Covenant aircraft with relative impunity, especially when the craft fly at low altitudes, such as the and  and the Type-26 Banshee. The Scythe can even quickly disable the shields of low-flying Seraph fighters. Scythe emplacements are also armed with an M41 rocket launcher to complement the main cannon.

The M71's tetrapodal base allows the emplacement to be deployed on varied types of terrain. It is usually synchronized with an automated tracking system or a defense-control artificial intelligence. The weapon's control panel is located on the body of the platform; this panel allows an operator to activate or deactivate the weapon, as well as to modify targeting parameters. The base of the weapon can also be used to employ the M95 Lance missile launcher instead, replacing the rotary cannon mount.

Operational history
Several Scythe turrets were placed around the Office of Naval Intelligence's SWORD and CASTLE Bases on Reach. One such turret was located at Airview Base, just outside Sword Base. On July 26, 2552, Catherine-B320 and SPARTAN-B312 of Noble Team were ordered to Airview Base to reactivate this turret, which assisted in repelling the Covenant's raid on the base. A few weeks later, a group of M71s was later used to defend the Sabre Program Launch/Research Range on Farkas Lake from Seraphs and Spirits.

In March 2553, it was discovered that the Insurrectionists on Venezia had several Scythes protecting New Tyne. In October 2559 M71 Scythes were used by the Viery Militia during Operation: WOLFE.

Trivia

 * In concept art, the weapon was known as the Vulcan, in reference to the M61 Vulcan Gatling gun. This weapon is also the source of the M41 Light Anti-Aircraft Gun's nickname.
 * The initial design for the turret had four Gatling-style cannons, while the final design only incorporates a single cannon. The weapon's design was inspired by the GAU-8 Avenger cannon mounted on the A-10 Thunderbolt.
 * Though the M71 is designed to be a rapid-firing rotary cannon, in-game, it possesses a low rate of fire, producing deep "booms", and the barrels do not spin until a burst has been fired. Realistically, the weapon should (like the GAU-8 upon which it was based) fire much faster, the barrels should spin while firing, and the weapon should emit a loud buzzing noise. Halo: The Essential Visual Guide reveals that the inconsistencies between the weapon's appearance and function are errors, and that it actually operates like a traditional Gatling-style rotary cannon; thus, it is likely that the Scythes encountered on ONI: Sword Base maintain low rates of fire to conserve their ammunition (as the only time one is seen, it is firing on a single Phantom).
 * In rare instances, the rotating turret can fall from the rest of the weapon and continue to fire at enemy aircraft. When detached, it rolls around and can be pushed with a vehicle.

List of appearances

 * Halo: Reach
 * Halo: Glasslands
 * Halo: Ground Command
 * Halo: Shadows of Reach