|Type-27 Anti-Aircraft Cannon|
Ultra-heavy plasma bolts
The Type-27 Anti-Aircraft Cannon, nicknamed the "Mantis", is a Covenant ground-based stationary anti-aircraft battery emplacement. It fires bolts of plasma that are extremely damaging. A single round can shoot down a GA-TL1 Longsword-class Interceptor and possibly even destroy a UNSC frigate with ease.
The bolts fired by the T-27 are in a teardrop shape, similar to normal plasma rounds, and fly in a straight trajectory. The plasma bolts are extremely powerful, since even their wake is able to take down a Longsword. It is unclear how powerful these weapons are, but during the Battle of Installation 00 it was reported that one AA gun could "tear the Dawn apart", implying that an AA battery would be powerful enough to destroy or seriously damage a UNSC Frigate.
An T-27 can be quickly assembled using modules transported by Phantoms. This makes them easy to deploy in the field. AA batteries are also often supplemented by deploying multiple Anti-Air Wraiths nearby.
The Mantis is sleek and light in construction, with the gun itself resting on three long legs. The gun's battery must cool off and release its excess heat after every shot, exposing its weak point; the interior is vulnerable through a vent on the underside the gun. A certain amount of damage to the interior will destroy the AA battery, making it vulnerable to infantry and ground vehicle attacks. Troops are often stationed on and around AA guns to safeguard them from ground forces.
The T-27 saw use during the Battle of Voi on November 17th, 2552, when at least one battery had been deployed in the town of Voi in order to keep the UNSC forces away from the Portal excavation. The UNSC planned a low-level strike, using Frigates and Longswords, to attack the Prophet of Truth's Forerunner Dreadnought which was resting on the Portal, which was thought to be the Ark by the UNSC at the time. Throughout the battle, the AA battery fired continuously, and managed to destroy at least one Longsword. Marines and John-117 eventually breached the Covenant resistance in Voi and destroyed the AA gun, allowing Lord Hood's ships to assault the Forerunner Dreadnought.
AA guns were also used during the Battle of Installation 00, when the Covenant tried to construct them on the surface of the Ark to keep the UNSC ships above from reinforcing their troops on the ground. However, these batteries remained incomplete, as SPARTAN-117, with the assistance of several Orbital Drop Shock Troopers stopped their construction, allowing the UNSC Forward Unto Dawn to land nearby.
In the Halo 3 level The Storm, the main objective is to destroy the Mantis in Voi so that Lord Hood can start attacking the Prophet of Truth's Dreadnought. Two T-27s under construction also appear in the level The Ark. AA Batteries are also mentioned in Halo: The Cole Protocol.
- The weapon's nickname of Mantis is fitting with the names of the Covenant's other heavy artillery weapons such as the Scarab and the Locust, which are all named after insects.
- The Mantis appears to be the successor to the Tyrant and the Covenant artillery.
- The Rocket Launcher requires two shots, to destroy the Mantis.
- You can also use multiple gernades to destroy one if you do not have a Rocket Launcher, Fuel Rod Gun, or Spartan Laser.
- A plasma pistol can also take down a AA gun with 2 EMPed shots to the core.