SWAT HQ Salvage Yard
Ireland Autoduel Association
IADA Car Wars Errata Sheet 1998 Edition

The following is an errata sheet/rules clarification for Car Wars arena dueling.

Because of the competitive nature of arena dueling, it requires a more precise set of rules than role playing or adventures with a referee. The advantages of more precise rules include that it is fairer for the players to know in advance what the rulings on certain common ambiguities in the rules will be, they result in fewer rules arguments, and unscrupulous players will find it less easy to exploit ambiguous rules especially in car design.

This sheet relates only to those rules and items available in AADA sanctioned events. Boats, helicopters and even passengers will not be considered, since they are illegal under the AADA rules in ADQ 9/1. Actually, it was originally intended that instead of an errata sheet, that this would be a full rewrite of those Car Wars rules used in arena dueling. However, the probability of the AADA accepting and publishing a rewrite is minimal, and I could hardly distribute the rewrite myself, since this would be tantamount to giving the Car Wars rules away free.

Unfortunately, Steve Jackson Games appears to be giving up on producing Car Wars products. Some role playing and GURPS material is being produced but arena combat material seems to have been dropped. This is a terrible pity, since the Car Wars rules have become exceptionally complicated and inconsistent and the game is crying out for a more precise and consistent (but not necessarily much less complicated) set of rules for tournament style arena combat between cars. The current rules are too ambiguous, have been written by too many people, are incomplete and are full of useless information all about varieties of baroque and esoteric vehicles that are totally irrelevant to the arena duelist.

These rules correct, clarify and add to the rules in CWC2, UACFH and ADQ 9/1, to bring these texts into line with the Car Wars rules as I understand them. Where possible, I try to quote the source of the ruling, although there are so many contradictory rulings that knowing which is correct is difficult. In addition, a number of unofficial clarifications and changes are included in this sheet. These are clearly marked as such, and do not form part of the official Car Wars rules. They may be useful as they make some clarifications on ambiguous rules on which I am not aware of any AADA ruling. They also suggest some changes to the official Car Wars rules which I think would be good.

These rules are not appropriate for role playing or adventures, the rules for which should always take second place to player interaction and speed of play. It should also be noted that these rules are appallingly ambiguous. To write a properly precise set of rules, they would need to be written in a formal language. If there are any computer scientists or linguists out there who are interested in such a project, feel free, but I doubt that the AADA would be willing to use them.

David Gregg
IADA President
July 1996

Note from SWAT HQ: The page numbers on the July 1996 edition of this document referred to Car Wars Compendium Second Edition (CWC 2.1). This page numbers in this edition of the IADA Car Wars Errata Sheet have been changed to reference Car Wars Compendium Second Edition Fifth Printing (CWC 2.5) and Uncle Albert's Catalog From Hell (UACFH).

Michael P. Owen
SWAT Webmaster
March 1998 and April 2015


CWC 2.5, p. 67 and UACFH, p. 155 -- Fireproof Armour

If a vehicle catches fire, fireproof armour takes 1 point of damage per turn, like normal armour.

CWC 2.5, p. 68 and UACFH, p. 156 -- Metal Armour

If a vehicle catches fire, metal armour takes no damage from the fire. ADQ X/X. (There are a number of contradictory rulings on this, but this is the latest I am aware of.)

Clarification: The only way to use metal and plastic armour together is with metal outside and the plastic inside. It is no longer possible to layer it arbitrarily as was allowed by Dueltrack.

CWC 2.5, p. 67 and UACFH, p. 155 -- Rubber Armour

Rubber armour (from "Hoverball" in ADQ 7/2) is omitted from the CWC 2.5 altogether.

A point of rubber armour costs and weighs the same as a point of normal plastic armour. Rubber armour takes half damage from collisions, but takes five times the normal damage from weapons fire.

-- Unofficial Clarification

Rubber armour may be fireproof, laser reflective or radarproof at the same cost and weight as plastic armour.

It takes a full five points of rubber armour to stop a single point of weapons fire. If there is less than five points remaining, then all of those points of rubber armor are destroyed AND the point of damage goes through.

Laser reflective rubber armour takes 2.5 times (rather than 5 times) normal damage from lasers. It takes a full 2.5 points to stop a single point of laser fire. Rubber armor cannot be bought in half point increments.

Weapons fire is defined to be any damage from any direct fire weapons, as well as damage causing dropped weapons, such as mines, flame clouds, etc. Rubber armor takes no damage from hand weapons that do not damage vehicular components.

Rubber armour may be used as a layer in composite armour, with metal and plastic. The outermost later be metal, but the designer may choose which order to place the rubber armour and plastic armour in. There may be only one layer of rubber and one layer of plastic.

If a vehicle with rubber/plastic composite armour catches fire, the one point of fire damage each turn is taken from the innermost layer of armour.

Rubber armour takes normal (one point per turn) from vehicular fires.

CWC 2.5, p. 68 and UACFH, p. 156 -- Carbon-Aluminium Frames

Just in case anyone is still in doubt, CA frames are legal in AADA events.

CWC 2.5, p. 68 and UACFH, p. 156 -- Streamlining, Sloping

Clarification: You must round up the number of spaces lost to streaming or sloping. You cannot keep fractions of spaces.

CWC 2.5, p. 68 and UACFH, p. 156 -- Six Wheeled Chassis

"You can either place the tires side by side or one in front of the other. In the first case, one wheelguard and one wheelhub protect both, but any excess damage on the outer tire (when shot at from the side) goes to the inner tire. In the second case, two separate wheelguards and wheelhubs are required, and excess damage only goes on to the next tire if fired at from the rear (front)." ADQ X/X.

-- Unofficial Clarification

It is suggested that the extra $100 for a six wheeled chassis should be added to the base cost of the chassis, that is before adding CA frames, chassis modifications, etc.

CWC 2.5, p. 69 and UACFH, pp. 59-60 -- Extra Power Cells

-- Unofficial Clarification

It is suggested that the cost and DP of extra power cells be calculated on the base cost and DP of the power plant as it appears in the table on p. 69 in CWC 2.5 and p. 157 in UACFH rather than the cost and DP after PCs, SCs and ISCs.

CWC 2.5, p. 69 and UACFH, p. 60 -- Improved Supercharger Capacitors

-- Unofficial Clarification

It is suggested that the number of DPs lost by triggering an ISC should be based on the DPs of the plant as listed in the table on p. 69 in CWC 2.5 and p. 157 in UACFH.

CWC 2.5, p. 69 and UACFH, p. 157 -- Loss of Engine

-- Unofficial Rules Change

There is an enormous number of different decelerations for a car that loses power, depending on whether it loses its plant, driver dies, runs out of ISC or N2O or whatever.

It is suggested that any time a car loses power, it decelerates at 5 mph/turn. This can be the result of the power plant/engine being destroyed, or the driver removing his/her foot from the accelerator.

If at any time, a vehicle finds itself above its top speed then the driver must, on that phase, either push the plant or remove his/her foot from the accelerator. If the driver pushes the plant then it takes damage as normal on p. 53 in CWC 2.5. If the driver removes his/her foot from the accelerator, the car decelerates 5 mph/turn.

 The 5 mph/turn deceleration from plant loss or letting up on the gas is considered part of normal deceleration. It is not in addition to braking.

** Consider rocket boosters/jump jets. **

CWC 2.5, pp. 69-70 and UACFH, pp. 157-158 -- Gas Engines

Note that according to official AADA rules, gas engines are, by default, illegal in the arena -- "If the arena is to be open to gasoline powered vehicles, this must be specified." This rule is rarely enforced, but it might be wise to seek further clarification, or design two cars, if no statement is made on gas engines.

Furthermore, all vehicles must have a range of 150 miles at cruising speed.

-- Unofficial Rules Change

Gas engines take far too little space. The new gas engine rules actually reduce the amount of space that gas engines take.

All gas engines bigger than 30 cid take one extra space. Note that this is not in any way official. It also represents a serious change in the balance of the game. Consider it carefully before you use it.

CWC 2.5, pp. 69-70 and UACFH, pp. 157-158 -- Gas Tanks

According to "Damage Location," CWC 2.5, p. 41, cargo is any internal component other than weapons, crew and engine. Thus, gas tanks are cargo for damage allocation.

-- Unofficial Rules Change

For damage allocation purposes, gas tanks are part of the engine compartment. Allowing zero space gas tanks to be part of the cargo gives an unfair advantage to gas engines.

Gas tanks may be placed in cargo space. ADQ X/X.

CWC 2.5, pp. 70-71 -- Engine Critical Damage Table

-- Unofficial Rules Change

If the suggested unofficial rules on power loss are used, then in item 8, the car loses 10 mph top speed per turn, but not necessarily decelerate to meet the lower top speed. Similarly, under 12, all power is lost and the car decelerates 5 mph/turn.

CWC 2.5, pp. 71-72 and UACFH, p. 158 -- Plasticore Tires

-- Unofficial Clarification

When a plasticore tire has taken 4 DP the rubber exterior strips off revealing plastic. At this point it is visible to other cars that the tire is a plasticore which has lost its rubber layer.

CWC 2.5, p. 72 and UACFH, p. 158 -- Steelbelting

CWC 2.5 and UACFH both say that steelbelting increases a tire's DP by 25%. However, it has been repeatedly asserted in ADQ that the proper amount should be 33 and 1/3%. It seems likely that the CWC 2.5 and UACFH value is incorrect since the change from 33 and 1/3% to 25% was not on any of the SJG errata sheets.

Therefore, the "official" ruling is that steelbelting adds one-third to tire DP.

CWC 2.5, pp. 71-72 and UACFH, pp. 158-159 -- Tires

The order of tire modifications:

A. Take a tire (std, HD, PR or solid)

B. Steelbelted it, if desired (+50% cost, +50% weight, +33 and 1/3% DP)

C. Add radial (+150% cost, +20% weight, -1 DP)
    OR offroad (+20% cost, + 5 lbs. weight, no DP change)
    OR -- Unofficial Clarification: Add slick (+300% cost, +100% weight, +1 DP)

D. Fireproof it (+100% cost)

E. Put it on a cycle (-50% weight)

CWC 2.5, p. 73 and UACFH, p. 160 -- Placing Weapons and Armour

"Up to two spaces worth of dropped weapons (four spaces on an oversized vehicle) may be corner mounted." In this case, dropped weapons include dropped weapons, gas weapons, gas streamers and flame cloud gas streamers.

CWC 2.5, p. 72 and UACFH, p. 159 -- Cargo

Gas tanks may be placed in cargo space. ADQ X/X.

CWC 2.5, p. 73 and UACFH, p. 160 -- Weapon Location Restrictions

No more than 1/3 of total spaces in a vehicle can be devoted to weapons that fire from any one side.

How do you calculate the number of spaces allowed per side?

A. Slope and/or streamline the chassis.

B. The total number of spaces is the sum of the remaining regular and cargo spaces.

C. Divide the total number of spaces by three and round down. The result is the maximum number of spaces per side.

How do you calculate the number of spaces of weapons on a side?

For each of the six sides of the vehicle, add up the spaces taken by all the weapons on that side.

The space taken by magazines is added to the space taken by the weapon to which it is attached. The space taken by component armour is also added to the weapon(s) it protects. The space taken by weapon concealment also counts. The space taken by rocket boosters and jump jets mounted on each side is added to the number of spaces mounted on each side.

Weapons and magazines mounted in the corner count against the 1/3 space rule for BOTH sides that make up the corner it is mounted on.

It is not clear whether turret mounted weapons count against the number of spaces that can be mounted in the top arc. The 2038 Wombat III took advantage of this ambiguity to attach 8 spaces of weaponry to its turret.

Although the 1/3 rule is part of the official rules, and is enforced in most chapter and regional events, it is virtually never enforced in the World Championships. If you are competing in the Worlds, ignore the 1/3 space rule. Countless published illegal world championship designs demonstrate that the number of spaces per side is never checked. It may seem unfair to use an illegal car, but your opponents will probably be driving illegal designs, so if you follow the rules you will be at a disadvantage.


CWC 2.5, p. 106 and UACFH, p. 44 -- Laser Battery

Clarification: "A laser battery is required if a gas powered vehicle is going to fire lasers or run power draining electronics (radar, IR, etc.)

CWC 2.5, p. 106 and UACFH, pp. 44-45 -- Laser Guidance Link

-- Type out the MANY rulings on LGLs. --

CWC 2.5, p. 106 and UACFH, p. 45 -- Magazine Switch

-- Unofficial Rules Change

It is suggested that the arena must specify before the arena starts the order in which the shots in different magazines will come from if the arena is put on automatic. If the player does not specify, then it is decided randomly.

CWC 2.5, p. 106 and UACFH, p. 46 -- Ramplate

Clarification: The entire front armor is taken into account when deciding how much a ramplate costs and weighs. You cannot make only part of the front armor a ramplate.

CWC 2.5, p. 106 and UACFH, p. 46 -- Rocket EWP

-- Unofficial Clarification

A rocket EWP is treated like a normal EWP for the purposes of wind resistance, being hit, ejection, etc.

CWC 2.5, p. 107 and UACFH, p. 47 -- Rocket Platform

If a rocket platform is carrying a targeting laser, the targeting laser is destroyed if the rocket platform is destroyed.

CWC 2.5, p. 107 and UACFH, p. 47 -- Rotary Magazine

-- Unofficial Clarification

If a weapon with a rotary magazine is put on automatic, the shots are fired in the order that they were loaded. If a shot is due to be fired on automatic but has already been fired in regular combat, then the shot in the next chamber is fired instead.

CWC 2.5, p. 107 and UACFH, pp. 47-48 -- Smart Link

There is a rather bizarre ruling on smart links in ADQ X/X which says that two smart linked, identical weapons, one in the turret, one on the front, can be fired together with a cyberlink and both get the full +3 bonus. Considering that CWC 2.5, p. 105 says that a cyberlink works like a SWC and an SWC "must be set on installation to aid a single weapon type in a single position" (CWC 2.5, p. 107), this ruling seems to almost certainly be in error. If it is correct, one wonders whether it applies to SWCs and HRSWCs.

In my opinion, this ruling is incorrect.

-- Unofficial Clarification

SWCs and smart links may not be combined. Although one (or both) of the smart linked weapons may have an SWC attached, the bonus from the SWC only counts when that weapon is fired alone. If both smart linked weapons are fired, neither gets the SWC bonus. To get a computer bonus for smart linked weapons, you need a full targeting computer.

CWC 2.5, p. 108 and UACFH, p. 53 -- Component Armour

Component armour is one of the most useful and abused accessories in Car Wars. There are countless rulings on specific cases of using component armour, but there has never, to my knowledge, been any clean up type ruling on component armor, to iron out all the ambiguities and abuses.

In a gas powered vehicle, the gas tank and engine may be component armoured together or separately.

A component may have a maximum of 20 lbs of component component armour per space. This corresponds to 2 points of metal armour or 9 points of laser reflective armour or 10 points of normal armour.

A volatile weapon that is protected by component armour will not explode from fire unless the weapon actually takes damage from the fire (i.e., after the component armour is destroyed).

Component armour need not match the armour on the outside of the vehicle.

Fire extinguishers, ISCs and nitrous oxide must be component armoured with the engine.

Dischargers may not be component armoured.

Items in rocket platforms or rocket EWPs may not be component armoured.

-- Unofficial Rules Change

The rules change that has been most badly needed on component armour is to delete the line "It effectively increases the DP of the component in question." This may have been a useful analogy when people just used plain old plastic, but not anymore.

For damage allocation purposes, components are divided into crew, cargo, engine and weapons. Within the crew, cargo and engine compartments, components may be armoured in groups or together. Thus, if a compartment holds three components -- A, B and C -- then each may be component armoured separately, or all three can be armoured together, and so forth. Under no circumstances can any component be protected by two or more layers of component armour.

Components from different compartments may not be component armoured together. Thus, unless the IADA rule stating that gas tanks belong in the engine compartment for damage allocation purposes is used, gas tanks may not be component armoured with the engine.

Items with 0 DP may not be component armoured.

Weapons on the same facing may be component armoured together, or a single weapon may be component armoured on one side or some weapons on a side can be component armoured and others not. The important thing is there is no more than one piece of component armor per side.

A volatile component armoured weapon will not cause a vehicle to explode as long as it is component armoured, however component armour provides no such protection against gas engines exploding.

CWC 2.5, p. 109 and UACFH, p. 55 -- Fake Wheelguards and Armoured Hubs

When fake wheelguards or fake armoured hubs are hit by weapons fire and destroyed, it is visible to everyone that they were fake.

CWC 2.5, p. 109 and UACFH, p. 56 -- Fire Extinguisher

-- Unofficial Clarification

Any turn that a vehicle has a positive fire modifier total, the fire extinguisher will attempt to extinguish (reduce to zero) the fire modifier.

If a vehicle is on fire, check to see if the extinguisher puts out the fire before applying fire damage.

CWC 2.5, p. 109 and UACFH, pp. 56-57 -- Heavy-Duty Shock Absorbers

HD shocks cost $400 per wheel, not $400 total.

-- Continue from here.

CWC 2.5, p. 109 and UACFH, pp. 57-58 -- Roll Cage

Midville enthusiasts will remember that the MONDOs were allowed to build a single vehicle with a few points of armour per side. One option for this vehicle was that it could have an open roof, allowing a 360 degree arc of fire to passengers and crew, at no extra cost, as long as it didn't have any top armour. Of course, this was long before there was any argument over official and unofficial rules. If such vehicles are still legal, do they have five or six armour facings? Rules lawyers?

CWC 2.5, p. 111 and UACFH, p. 63 -- Antilock Braking System

-- What about oil on ice? --

CWC 2.5, pp. 111-112 and UACFH, p. 66 -- Car-Top Carrier

-- Unofficial Clarification

Car-top carriers and fake car-top carriers are illegal in AADA events.

CWC 2.5, p. 113 and UACFH, pp. 82-83 -- Jump Jets

from ADQ 9/1

"Jump Jets: $150 per 20 lbs, 1 DP and 1 space per 100 lbs. or fraction thereof. Volatile. 20 lbs. of jump jet will lift 1,000 lbs. of vehicle 1/4" (3.5 feet) off the ground. 50-lb. jump jets are available, costing $375, taking up one space, having 1 DP. A 100-lb. jump jet would cost $750, take up 1 space, have 1 DP and lift the car to 1/2" altitude. A 200-lb. jump jet would cost $1500, take 2 spaces, have 2 DP and lift the vehicle a full inch (15') of altitude.

When a jump jet is ignited, the car lifts from the surface at 1/4" per phase until the maximum altitude is reached, and then descend at 1/4" per phase until it reaches the ground. The vehicle is not considered to reach the altitude it is heading for until the end of the movement phase. Thus a vehicle at 1/4" altitude at the beginning of a phase.

Published by David Gregg, July 22, 1996.
Reprinted by the Seattle Washington Autoduel Team, March 08, 1998.
Updated March 31, 2015 and May 03, 2015.
Original URL: http://arrakis.ucd.ie/~greggd/IADA.html
Original URL: http://arrakis.ucd.ie/~greggd/IADAerrata.html