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Weapon & Equipment Information
General Details
Name:  C3 Computer (Master)
Type (Category):  Equipment (Other)
Technology:  Inner Sphere
Available To:  BattleMechs
Reference:  TechManual (p. 209)

The Command/Control/Communications (C3) system is easily among the Inner Sphere’s most potent recent inventions. It is also one of the most original, considering that it emerged not as the result of a Star League tech recovery, but as a new application of technologies. As much a revolution in battlefield technology as one of combat philosophy for its creators in the Draconis Combine, the system is essentially an elaborate tight-beam communications suite, designed to link the sensors and targeting systems of up to a full lance of friendly units in a single, closed network. The C3 system enables those within its network to draw targeting data from one another and coordinate fire with amazing ease. As long as effective weapon ranges and lines of fire permit, a member of a C3 network can essentially strike at a target with the same accuracy as the nearest friendly network member. Moreover, units that mount a C3 master computer—with the other network members using slave nodes—can use the computer’s coordination as an improvised TAG system.

The system, of course, has its limits. Only units in the same network—generally a single lance, though creative deployment of multiple master computers per unit may allow for networks as large as a company—may share targeting data in this fashion. Friendly units with systems outside the network cannot simply “tap in” at will. Further, the network signals and data streams are susceptible to jamming by enemy ECMs. Worst of all, the hierarchical nature of the system means that the loss of the master computer to destruction or ECM interference crashes the entire network, leaving its surviving units to fend for themselves.

Sad to say, the biggest obstacle to optimum use of the C3 system is a matter of ego more than technology. Ironically produced by a realm with a strong sense of personal honor and a warrior’s code, the concept of a communal targeting and communications network is often lost on the warriors of the DCMS. Indeed, despite efforts to force a more widespread distribution of the technology, this mentality has apparently kept an otherwise powerful system virtually marginalized on the battlefield, even as other factions adopt similar systems of their own.

Game Rules:
A unit’s C3 systems are considered active in game play as long as the systems are not hit in combat, the unit’s engine is not shut down and the unit is not destroyed. Otherwise, these systems continue to function, even if the pilot/crew is unable to act.

The C3 computer system can link up to twelve ’Mechs or vehicles together—utilizing a series of C3 Master and C3 Slaves—in a communications network that will share targeting information.

To make an attack using a C3 computer network, calculate the to-hit number using the range to the target from the networked unit nearest the target. Use the firing unit’s modifiers for movement, terrain effects, minimum range and so on. A weapon attack using a C3 network must conform to standard LOS restrictions and cannot fire beyond its maximum range, though a well-placed lancemate may allow the firing unit to use his weapon’s short-range to-hit number at long range.

The C3 network itself has no maximum range, but only units actually on the playing area can benefit from the network, and the C3 Master (or C3 Masters if using a company-sized network) must be on the playing area.

While a unit may mount both a C3 Master and a C3 Slave, it may not use both at once. For units so equipped, at the start of game designate which C3 system is operational. A unit may only belong to a single network.

TAG: The C3 Master (but not the C3 Slaves) exactly duplicates the function of target acquisition gear.
LOS: While units must have LOS to a target to make an attack using a C3 system, the C3 system itself need not have LOS.
LRM Indirect Fire: A C3 network does not help when launching or spotting targets for indirect fire. Note that TAG (which conveys the benefits of spotting if it hits) does benefit, however.
Minimum Ranges: Minimum range is always determined from the attacking unit to the target.
Variable Damage Weapons: The range, to determine the Damage Value of a Variable Damage Weapon, is always determined from the attacking unit to the target.
Stealth Armor: Armor that inflicts range modifiers against attacking units does not confuse a C3 network. Only apply the additional range modifiers based on the range between the target and the nearest unit in the network; do not apply modifiers based on the range between the target and the attacking unit in the network. The only modifiers to consider between the attacking unit and the target are Minimum Range modifiers.
Water: If a C3 of any kind is in a location of a unit that is above the surface of a water hex, it cannot be linked to a C3 system underwater. In other words, for a C3 of any kind to be linked underwater, it must be able to draw an LOS to the other units in the C3 system that passes only through underwater hexes (note that this need not be a clear LOS, as noted above). The one exception are naval vessels. If a C3 of any kind is located in the “body” of a naval vessel, on the surface, the C3 can be linked to units both above and below the water.

Construction Rules:
May be mounted on any available unit type with adherence to the following construction rules:
 Not allowed in conjunction with Improved C3 Computer, Null-Signature System, or Void-Signature System
Inner Sphere Data
Prototype Date:  ~3039
Production Date:  3050
Extinction Date:  —
Recovery Date:  —

Heat (Aero)
Damage (Aero)
Range (Aero)
Cost (C-bills)
Weight (Tons)
Battle Value
0 (0)
– (–)
– (–)

Start Year
End Year
Rules Level
Tournament Legal

Special Abilities
C3 Master Computer, Mobile Headquarters, Target Acquisition Gear

Special Unit Abilities
The special unit abilities described here are intended for use with the Alpha Strike rule system:
 C3 Master Computer (C3M)
The C3 master computer enables up to four units to share targeting information and receive the benefits of the C3 network. One unit in a four-member C3 network must have the C3M system to act as the “master”. The other three units in the network must have C3 equipment of their own to be part of that “master’s” network. These member units can use either their own master computers, or C3 slaves to accomplish this.

If a C3 network has multiple “masters”, each “master” needs to designate three other units as part of its network. Units with multiple C3Ms can even use them to coordinate multiple networks via the same “master”, as demonstrated in the C3 configuration Diagrams.

 Mobile Headquarters (MHQ)
The standard MHQ is equipped with a wide array of special equipment to coordinate engagements over a large area. This ability provides different bonuses depending on the numerical rating.

 Target Acquisition Gear (TAG)
TAG is used to designate targets for homing artillery attacks. A unit with this ability may designate targets in the Short and Medium range brackets.

MTF Output → Weapon List:  C3 Master with TAG
MTF Output → Critical Slot:  ISC3MasterUnit
PDF Output → Critical Slot:  C3 Computer (Master)