Optional Rules Compendium

This is a compilation of "house rules" for the BattleTech gaming system. These rules come from different sources and might not be used by your GM. If your gaming group does not use a GM, then rules can be adopted by general consensus of the players. Please note that some of these rules may conflict with each other; this list is meant to complement existing rules.  This list is based on FASA's BattleTech, not the newer version by FanPro (Classic BattleTech).
Use of the phrase "House Rules" in no way implies that the sequenced garbage played in dance clubs in the early 1990's was even music, let alone any good.

Actuators* Armour* Critical Spaces* Conventional Aircraft* Damage and Repair* Endo Steel* Ferro Fibrous* Hatchets* Heat Sinks* Misc.* Physical Combat* ProtoMechs* Quads* Weapons and Equipment
Dropships | Warships
VehiMechs | Centaurs | Spiders

Some of the rules listed here are clarifications. These rules are mostly for campaigns or large scale battles. Rules involving personel are better applied to cargo space than factored into dropship construction.

Dropships

AeroSpace Fighter Bays

The weight of the AeroSpace Fighter is assumed to be included. If the bay is empty, the Dropship can carry an additional 100 tons of cargo (in the cargo bay).

AeroSpace Fighter Launch and Recovery

AeroSpace Fighters cannot launch from or be recovered by grounded dropships. Grounded AeroSpace Fighters must either be loaded into the dropship like cargo (assume the ship has facilities) or must dock with the dropship in space. Although they can launch, AeroSpace Fighters cannot dock with a dropship in atmospheric transit.

A fighter leaving a dropship in atmospheric transit must make a piloting skill roll with a +5 penalty to exit the ship safely. Failure indicates that the fighter is 1-3 destroyed or 4-6 falling uncontrolled toward the surface. If the fighter is destroyed while exiting the dropship, the fighter bay/door takes damage.

Carrier-like catapults would accelerate the pilot too quickly or be too bulky use.

Current BattleSpace rules prohibit launch/recovery of fighters on the ground and in atmospheric transit.

Aero Tech Conversion

BattleSpace dropships can be easily converted to AeroTech and BattleTech compatible units. Multiply a weapon's fire factors by 10. Each weapon attack is resolved separately, not by weapons bay. Armour values are also increased by a factor of 10 when defending against AeroTech weapons. Weapon ranges are per AeroTech, using "overcharge" mode for firing weapons in space.

see also BattleTech Conversion

Armour

Dropship armour comes free with the design, at no monetary cost.

Tonnage must still be allocated for armour.

Armored Infantry

A dropship designed to carry Elementals or other armored infantry can add those troops to their Marine Rating if they are on board. Since IS armored infantry may not be specifically trained as marines, change the value from 1 to .75 per trooper.

Armored Marines

To properly support Elementals or Armored Marines, tonnage (can be cargo) and cost for a maintenance and storage area must be allocated. Support areas must be allocated in full point increments.

BattleTech Conversion

Dropship weapons convert to normal BattleTech weapons on the ground. Ballistic weapons are now fully subject to gravity and thus fire as normal BattleTech weapons. Atmospheric interference reduces the range of energy weapons (the AeroTech fluff cannot cut it here). Armor values increase by a factor of 10.

Use of BattleSpace weapon ranges gives dropships an ungodly range capable of raining PPC fire several kilometers away. Using only a 10:1 armor conversion may make dropships seem fragile, but it is important to remember, dropships are mostly hollow.

Capital Weapons

Dropships can mount capital ship weapons. BattleSpace construction rules refer directly to the capital weapons page. The Fox's Teeth contains a scenario in which a crashed dropship is able to bring it's Main Gun online, obliterating target 'mechs on a to-hit roll of 9 or better.

A capital weapons bay takes 2 of a firing arc's 8 weapons bays. A dropship capital weapons bay may hold 50 fire factors worth of weapons. Capital weapons bays in side firing arcs must match to maintain ship symmetry. A capital weapons bay may also be limited to 1 weapon per firing arc.

Fluff: The reason most dropships do not carry capital weapons is that they simply weigh too much. Even though the larger dropships could easily carry such big guns, the owners of such ships do not wish to sacrifice the cargo capacity. If you need a big dropship, you need a big dropship.

Since dropships have so little armour compared to their jump-capable big brothers, they cannot readily trade fire with warships. The high cost of capital weapons also limits their use.

Cargo - 'Mechs and Vehicles

BattleMechs and vehicles may be carried as cargo. They must be secured as cargo and take additional unloading time before being deployed. 'Mechs are transported horizontally to avoid falls, so they must be unloaded then "unpacked" before they can by activated.

Counters

see Size.

Doors

Although BattleSpace rules specifically limit the number of cargo doors to 40, 'Mech and Vehicle doors should be included in this limit. Hot drop (for 'Mechs or Vehicles) or Aerospace Fighter doors do not need to be included in the limit as they can be mounted "higher" on the ship.

'Mechs and vehicles can enter and exit through cargo doors if they occupy the same ship bay. For example, if a 'MechBay and a Cargo Bay are both located in a dropship's number 2 bay, the BattleMechs may use the cargo doors. 'Mechs and vehicles cannot hot drop from cargo doors.

Firing Arcs (grounded)

BattleForce gives grounded dropships 3 firing arcs, 2 hexsides per arc.

Spheroids
Fire factors can be divided equally among the three arcs. This precludes individual targeting of weapons but makes bookkeeping much simpler. Nose and Aft weapons should not be considered in determining the fire factors. BattleForce allows for all 3 arcs to simultaneously track AeroFighters, but this should be subject to LOS. Nose weapons can be figured in when targeting aircraft.

Aerodynes
Normal firing arcs should be used for aerodynes. If using the BattleForce 3 arc system, it works best to assume that the dropship is facing a corner instead of a hexside. Nose weapons can fire in the "front" arc and wing and aft weapons can fire into the "back" arcs.

Flamers

Flamers do not work in space.

Flamers cannot fire during atmospheric transit.

Hot Dropping

Suborbital drops in which a 'mech must wear a protective drop cocoon necessitate an ejection system rather than a conventional door. There are decompression considerations as well as the incredible heat of re-entry. Turbulence from the gap caused by a 10m+ tall door would prohibit occupancy of the 'MechBay.

AeroTech rules listed 'Mech Doors as drop doors, 'Mechs had to re-enter through cargo doors. BattleSpace separates 'MechBays and Cargo Bays into closed off ship bays.

Having an ejection system as an integral part of each individual 'MechBay would require direct access to the ship's outer hull, just as weapons and doors. Fortunately, these need not be ringed around the bottom of the dropship.

Landing

Since dropships occupy more space than a single 30m hex, a landing site must be large enough to accommodate them. Dropships over 600,000 tons can land in light woods or on small buildings with impunity as their mass drive plumes will easily clear the hexes of these obstructions.

LB-X Autocannon (IS)

Loaders

Inside the dropship are all manner of cranes and gantries for moving cargo, but ground operations may require special loaders. Due to physics, a loader must be heavier (whether through anchors, balances, or sheer mass) than the object it is lifting. Use the Maximum Tech Super Heavy Vehicle rules if you wish to design such a vehicle. Transports do not have to heavier than the object they are intended to carry.

MechBays/Cocoons

The allocation of tons per bay is assumed to include the up to 100 tons of 'Mech.

MRMs

MRMs must be mounted in the LRM weapons bay. MRMs use the cost/weight/heat stats found in the BTFM:DC and BTMR.

Naval Vehicles

Naval vehicles can only be carried as cargo.

Quarters: Carried Troops, Warriors, Pilots

BattleSpace construction rules allow the accommodations for all military personnel to be included with their materiel. These options allow for a more realistic campaign, but have little effect on board-level gameplay.

Although tonnage is allocated for infantry and armored infantry, quarters are required for each trooper. The pre-assigned weight is attributed to the storage bins and the equipment carried by the troops, such as armor, extra weapons and ammo.

Troops can temporarily camp in cargo areas, taking 1 ton of cargo space per trooper. This allocation reflects the premium of floor space and the extra materiel required to support each trooper. Even gro-pos need acceleration couches.

MechWarriors, AeroSpace Pilots, and Vehicle Crews are all considered passengers.

Marines are considered crew.

Quarters: Weight

A private cabin section weighs 7 tons per person.

A semi-private cabin can be designed for 4 tons per person.

Repair: Mechs

Since dropships should have all manners of loading equipment, repairs to BattleMechs inside the dropship can be accomplished more quickly than in the field (assuming the ship is not full and too crowded). Repair time and difficulty can be lowered at the GMs discretion.

Size

Many of the dropships described in BattleSpace are considerably larger than the generally accepted 1 hex. Two of the spheroid dropships are nearly 300m in diameter, prompting the need for special LOS considerations. A 100m Spheroid dropship rises 10 elevation levels!

Counters:

ds-90.gif

ds-270a.gif | ds-270b.gif ds-270c.gif | ds-270d.gif

Small Lasers

Small lasers, ER small lasers, and small pulse lasers may be mounted in their appropriate laser bays as well as the point-defense bay.

Streak SRMs

Super-Heavy Vehicle Bays

Super-Heavy Tanks can be carried as cargo, but cannot be deployed directly in to combat.

Super-Heavy Vehicle Bays can be created at double the weight and triple the cost of standard vehicle bays. Super-Heavy Vehicle Bays allow Super-Heavy Tanks to deploy immediately upon landing, if an appropriate door is available.

Swords

You've got to be kidding.

Ultra Autocannon

Vehicle Bays

The weight of the vehicle is included in the weight of the vehicle bay.

VTOLs

VTOLs can be carried as cargo or in vehicle bays but cannot be deployed immediately into combat.

VTOLs cannot be launched from AeroSpace Fighter bays, but may be transported in them.

Weapons Bays

There are limits to the number of weapons in a bay, but there are no limits to the number of bays listed in BattleSpace. The warship construction rules are also vague on this point. By looking at existing ships, dropships can obviously have more than one type of weapons bay per arc.

Each firing arc may have one weapons bay of each type. If an arc is armed with exclusively one type of weapon, i.e. all lasers or all missiles, that arc may support 2 weapons bays of the same type.

Alternately, each firing arc may have up to 8 weapons bays of any type. Each bay must contain only one type of weapon per bay. Only 64 weapons may be mounted in a firing arc.

Weapons Conversion

Dropship weapons become their standard BattleTech namesakes upon leaving space. The reasons for the much shorter ranges include atmospheric interference and gravity. Each weapon may be targeted independently or grouped in to fire factors.

Weapons Fire

In AeroTech, dropships are not allowed to fire weapons in atmospheric transit. This can be thought of as closing the gun ports to provide heat shielding. This also makes dropships very vulnerable to orbital and ground-based fire.

The BattleTech storyline provides for weapons fire during atmospheric transit. While dropships sport considerable firepower, they have relatively light armour and are prohibitively expensive to replace.

To submit a rule for posting, e-mail Koichi (please include "BattleTech" in the subject line) href="mailto:MechWorks@mail.freeyellow.com">e-mail Koichi

This list was compiled by Jason Caesar and Koichi Ishitandai

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