- The Modern BattleMech -

The modern BattleMech is perhaps the most complex machine ever produced. Each 'Mech contains thousands of different components, far too many to explain here. But exploring the systems and the capabilities of BattleMechs is a great way to start getting to know these marvellous machines.

Skeleton

Every BattleMech contains a 'skeleton' made up of several dozen 'bones.' Each 'bone' is a honeycombed, foamed-aluminium core wrapped with stressed silicon-carbide monofilament and protected by a rigid, titanium-steel shell. Each of these artificial 'bones' has attached points for the myomer 'muscles' and servos that drive the BattleMech. This skeletal construction helps to make the BattleMech less vulnerable and easier to repair than vehicles supported by stressed-skin shells.

Muscles

Two different systems are used to drive BattleMechs and control their movements. Small, electrical driven actuators move a 'Mech's light weapons and sensor arrays. Bundles of polyacetylene called myomers control a 'Mech's limbs and main weapons. Myomers contract when exposed to electrical current, much like human muscles. If a BattleMech's myomers are damaged in battle, technicians can replace the fibre bundles with new ones or transplant myomers from other parts of the 'Mech's skeleton. Transplanted myomer bundles cannot restore full function to a damaged limb, but they do provide limited mobility and strength.

Armour & Weapons

Two separate layers of armour provide modern BattleMechs with protection against energy and projectile weapons. Usually, aligned-crystal steel is used for an outer layer of armour. The aligned-crystal steel has excellent heat-conducting properties, and so it provides excellent protection against lasers and particle-beam weapons. An inner layer of boron nitride impregnated with diamond monofilament stops high-explosive armour-piercing (HEAP) rounds and fast neutrons. This second layer of armour also prevents any armour fragments from damaging the BattleMech's internal systems.

BattleMechs usually carry charged-particle-beam weapons or lasers as their primary armaments, because energy weapons can be powered virtually indefinitely by a 'Mech's onboard fusion reactor and do not require ammunition reloads. In addition to energy weapons, many BattleMechs carry launching racks for short- or long-range non-nuclear missiles. Other 'Mechs mount rapid-fire autocannons or machine guns for use against infantry, aircraft and other BattleMechs.

Power

BattleMechs require a large, constant power supply for movement and combat. The fusion reactor, which produces enormous amounts of electricity from ordinary water, is the most efficient system for providing this power. Because the fusion reaction, created by a BattleMech's power plant, does not release neutrons, the power plant can operate indefinitely without becoming radioactive.

The fusion plant produces electricity by a process known as magnetohydrodynamics (magneto-hydro-dynamics). In this process, magnetic fields are used to channel plasma from the fusion reactor into a loop. This plasma is electrically conductive, and so the loop functions as a powerful generating coil, producing both electricity and waste heat. Every BattleMech carries radiators called heat sinks to help dissipate the waste heat. Heat sinks are especially important, because extensively high temperatures can disrupt the magnetic containment fields around a BattleMech's reactor. If a power plant's magnetic "jar" is disrupted, an uncontrolled fusion reaction may occur, releasing neutrons and exposing the BattleMech's internal systems and its crew to damaging and lethal radiation.

Movement

BattleMechs can attain walking or running speeds ranging from 40 to 100 kilometres per hour in open terrain. Dense forests, swamps and steep slopes will slow a 'Mech, but very few terrain features can stop one. In addition, many 'Mechs can jump over obstacles by superheating air with their fusion reactors and jetting it out through so-called jump jets. Jump-capable BattleMechs operating on worlds without atmospheres often carry small quantities of mercury to use as reaction mass for their jets. All BattleMechs can wade through water when crossing rivers or small lakes.

Spaceborne BattleMechs can make assault landings from low orbit. Special reaction jets housed in their feet allow them to soft-land from altitudes of up to 320 kilometres. During re-entry, breakaway ablative shields protect a BattleMech's vulnerable sensors and weapons.

Weapons & Heat Dissipation Strategies

Because a BattleMech's systems are pushed to their limits during combat, 'Mechs engaged in battle generate large amounts of waste heat rapidly. While excessive internal temperatures can disrupt a fusion reactor's magnetic containment shield, excessive heat can also impair or permanently damage a 'Mechs electronics and computer systems, slowing the BattleMech's movement and reducing the accuracy of its weapons.

Heat sinks are one way of controlling heat build-up, but the heat pouring out of these radiators can produce strong infra-red (IR) signatures, which make a 'Mech easy to target. In order to try and solve this problem, MechWarriors have found other ways to control heat build-up. Often, MechWarriors will place their machines in shallow lakes or rivers, if possible. Through the processes of conduction and convection, the running water helps to dissipate the 'Mech internal heat, allowing a higher rate of activity. On cold worlds, the atmosphere itself can help to dissipate the waste heat in the same manner. On the other hand, the high outside temperatures of a desert or jungle environment can exacerbate a BattleMech's heating problems.

Because a 'Mech can become so hot, pilots are at great risk from being over exposed to the great levels of waste heat generated all over the machine, including inside the cockpit. To combat this, all pilots are equipped with a cooling vest. This vest covers the pilot's upper torso and helps to keep his body cool, much like the reverse of a hot water bottle. The internal cockpit temperature determines the cooling rate of these vests.

Perhaps the most common way that MechWarriors control heat build-up is by regulating the movement and firing rates of their machines manually or by reprogramming the machine's movement control computer and secondary systems. These computers can be set to limit the 'Mech's rate of activity and the resulting heat build-up. For example, when a 'Mech is sent to an area with a high temperature atmosphere, its activity-rate setting may be lowered. The 'Mech will then be less capable of moving fast and firing its weapons rapidly than it would in a cooler environment. When a 'Mech is sent to fight in an arctic climate, the setting is raised, allowing faster movement and a higher rate of fire. Re-programming is usually carried out while the BattleMech force is en-route to its assignment aboard the dropship. The process takes approximately 1-2 weeks, depending upon how many settings must be altered.

Because BattleMechs are often adjusted for the expected external temperature of their combat environments, sudden increases in outside temperature can have a devastating impact on a 'Mech's ability to dissipate waste heat. Tacticians have developed a whole series of battle tactics to take advantage of this 'Mech characteristic. For example, commanders regularly set forests on fire while enemy BattleMechs are advancing through them. The superheated air roaring around the 'Mechs can overload the machines cooling systems or drastically reduce their efficiency, thus hampering the machines' combats capabilities. All BattleMechs have a "heat spike" detection system as part of their sensory equipment.

"Utilizing a weave of ferro-steel and ferro-titanium fibres, this armour plating increases tensile strength by 12 percent."

-Star League Field Library, Helm