| Model number: RX-77-3 Code name: Guncannon Heavy Arms Type Unit type: prototype artillery mobile suit Manufacturer: Earth Federal Forces Operator: Earth Federal Forces First deployment: UC 0079 Accommodation: pilot only, in standard cockpit in torso Dimensions: overall height 18.1 meters; head height 17.5 meters Weight: empty 58.6 metric tons; max gross 79.1 metric tons Powerplant: Minovsky type ultracompact fusion reactor, output rated at 1380 kW Propulsion: rocket thrusters: 62200 kg total Performance: maximum thruster acceleration 0.79 G; maximum ground running speed 69 km/h Equipment and design features: sensors, range 6000 meters Fixed armaments: 1 x 240 mm cannon, mounted on backpack over shoulders; 2 x 60 mm vulcan gun, fire-linked, mounted in head Optional hand armaments: beam rifle, powered by rechargable energy cap; grenades, stored in optional grenade rack on left hip armor |
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| During the development of the GM Cannon, the Federation's engineers kept working on the original RX-77-2 Guncannon design. A third version of the Guncannon, dubbed the Heavy Arms Type, was produced for testing purposes. Previous incarnations of the Guncannon and GM Cannon were designed as support units, to supplement teams of close-combat mobile suits. The Heavy Arms Type, on the other hand, was intended to be a self-sufficient mobile suit that could be used to form all-Guncannon teams. Its armor and armament were improved, with modified cannons and a handy grenade rack. The Heavy Arms Type was later used as a testbed for a new type of beam cannon. |
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