Main Battery

This system represents a ship’s principle offensive weaponry; the standard ship-to-ship weapons of whatever fiction the ship lives in. A single battery can represent several mounted barrels, emitters, or turrets working in tandem; or a single turreted weapon with one or more barrels/projectors. It is less effective at long range due to accuracy of firing solutions, spread of the individual projectiles/rays, etc.

Symbols:

Rolling To Hit

To determine the effect of firing on a target, a number of dice are rolled depending on range. Class-3 batteries have a maximum range of 36″. When firing at a range of 0-12″, three dice are rolled; at 12-24′, two dice; and at 24-36″, one die. The following table shows the number of dice to roll indexed by battery class and range to target.

Battery	0-12″	12-24″	24-36″	36-48″
Class-1	ONE D6	—	—	—
Class-2	TWO D6	ONE D6	—	—
Class-3	THREE D6	TWO D6	ONE D6	—
Class-4	FOUR D6	THREE D6	TWO D6	ONE D6

Unscreened Damage

Damage is dealt according to the results of the dice. The target ship must cross off a number of jhull boxes according to the total damage points generated as detailed in this table.

Per six-sided die	Result
Every 1, 2, or 3 rolled	No effect
Every 4 or 5 rolled	One damage point
Every 6 rolled	Two damage points

Damage Protected by Screens

Defensive screens reduce the damage from main batteries.

For a ship with at least…	Per incoming main battery die
Level-1 Screens	Rolls of 4 have no effect
Level-2 Screens	Rolls of 6 inflict only one point of damage

Class-1 Point Defense Mode

Class-1 beam batteries can be fired in defense against approaching small craft and missiles. This requires the use of one fire control system, but this one can be shared among any number of Class-1 batteries being used in point defense mode.

1D6 is rolled as normal, but only one hit is scored on a roll of 5 or 6 (as if being affected by level-2 screens).

Design Procedure

Battery	Bearing	Mass	Cost
Class-1
	360° (6-arc)	1	3 points
Class-2
	120° (3-arc)	2	6 points
	360° (6-arc)	3	9 points
Class-3
	60° (1-arc)	3	9 points
	120° (2-arc)	4	12 points
	180° (3-arc)	5	15 points
Class-4
	60° (1-arc)	5	15 points
	120° (2-arc)	8	24 points

Lore

The nature of the main battery must conform with the basic rules: its a barrage of something that hits roughly 50% of the time, and damage can be reduced by defensive systems mounted on the target. This lends itself to the concept of laser beams, phaser beams, and particle beams, but it doesn’t rule out high-velocity projectiles or other ballistic missiles.

Laser and Blaster Beams: Energy beams fired upon the target in volleys or a continuous beam over the course of a turn. Defensive systems are energy shields that absorb, deflect, or dissipate the incoming beams. The shields can be overloaded by especially direct shots allowing some damage through.

Phaser and Particle Beams: Hyper-accelerated particles fired toward the target in volleys or beams. Defensive systems can be energy shields or magnetic fields that dissipate the incoming particles, lessening the chance of damage.

High-velocity Projectiles and Ballistic Missiles: Gun barrels or launch tubes fire volleys of penetrating slugs or small rockets. Defensive systems are likely some form of active armor or laser-based point interceptors that physically deflect or vaporize some of the incoming weapons.

You can optionally rule that screen generators simply don’t exist in your setting and require ships to use some kind of ablative armor, or even trade standard batteries for ships with only torpedo systems creating a different flavour of sci-fi.

External Links

Main battery - Wikipedia

Ship Design Navigation Table
Basic Design	Faster Than Light Drive • Fighter Group • Main Battery • Normal Space Drive • Point Defense System • Screen Generator •
Advanced Design	Drone System • Needle System • Submunitions • Torpedo System
Experimental Design	Advanced Battery • Advanced Drive • Advanced Fire Control • Advanced FTL • Megabattery • Railgun System •