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 re-create 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 re-rolled.
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"