The FA-78-1 Gundam Full Armor is the upgraded form of RX-78-2 Gundam. The upgrade program, called the Full-Armor System and Weapon System (FSWS), developed several options packs to increase the Gundam's already considerable power.However, due to the Full Armor Gundam's massive increase in weight, it suffered a sharp drop in mobility which the new thrusters could not sufficiently compensate for. It was deemed that the loss in speed and maneuverability would be unacceptable and the Gundam Full Armor Type never left the development stages. The Gundam Full Armor Type would never be built, and only existed on paper. However the plans for the unit would later be used as the basis of creating the FA-78-2 Heavy Gundam.(wiki)