Ferro-Fibrous armor (FF) is a special type of armor used by vehicles and BattleMechs. Utilizing a weave of ferro-steel, ferro-titanium, and diamond weave fibers which boosts the tensile strength of the plating, it provides more protection per ton than standard armor (12% for Inner Sphere FF, 20% for Clan FF), but takes up more space on the 'Mech or vehicle (14 critical slots for Inner Sphere, 16 for prototype Inner Sphere, and 7 for Clan 'Mechs; two slots for Inner Sphere vehicles (three for prototype IS), one for Clan). The maximum amount of protection is not changed; merely the weight of armor required to achieve that level of protection. For a unit which already has maximum armor protection, it is therefore considered a weight-saving measure, at the cost of critical space. The weight savings for Endo Steel are greater than those saved by ferro-fibrous armor, but it is more costly and obviously more difficult to repair or add as an upgrade to a 'Mech.
First developed by the Terran Hegemony as a prototype in 2557 and mass produced in 2571, Ferro-Fibrous armor was lost to the Inner Sphere during the Succession Wars. The Draconis Combine was the first to recreate it in 3040. Later, the Free Worlds League and Lyran Alliance would develop Light and Heavy versions of Ferro-Fibrous armor.
Ferro-Fibrous Armor does not suffer from critical hits; any rolls upon a space occupied by any type of Ferro-Fibrous should be rerolled.
FF Armor is a Standard Rules piece of Equipment under the current system and was Rules Level 2 under the previous system. Armor of this type produced in the Inner Sphere has a Technology Rating of E while Clan produced armor has a Technology Rating of F. As with all combat vehicle armor types Ferro-Fibrous is assumed to have a Barrier Rating of 10.
Ferro-Fibrous armor is manufactured on the following planets:
Inner Sphere Armor Types
- TechManual, p. 205, "Armor - Ferro-Fibrous"
- MechWarrior 4: Vengeance (Resource)
- Interstellar Operations, p. 72, "Ferro-Fibrous Armor-P"
- Total Warfare, p. 135, "Ferro-Fibrous Armor"
- Technical Readout: 3055 Upgrade, p. 56, "HRC-LS-9000 Hercules"
- Technical Readout: 3145 Capellan Confederation, p. 24, "Behemoth II"
- Technical Readout: 3058 Upgrades, p. 106, "Typhoon"
- Objective Raids, p. 124, "Produced Gibson BattleMech Components"
- Technical Readout: 3058, p. 198, "Maultier"
- Objective Raids, p. 105, "Produced Independence Weaponry Components"
- Technical Readout: 3060 (Reprint), p. 122, "TSH-7STai-sho"
- Technical Readout: 3067 (Reprint), p. 68, "TSN-1C Tessen"
- Technical Readout: 3060, p. 110, "JagerMech III"
- Technical Readout: 3145 Mercenaries, p. 26-27, "Kite Reconnaissance Vehicle"