Starship combat

From MegaTravellerWiki

This article is a work in progress and may not be complete enough to use in your MegaTraveller campaign. Feedback and ideas on Talk:Starship combat are welcome.

In MegaTraveller, starship combat is loosely simulated and obeys some strange constraints; though these constraints were done in the interest of ease of use, they reduce the game's realism significantly. In my eyes, a little too significantly.

The MTWiki starship combat system is a tactical boardgame within the MegaTraveller ruleset that more directly represents how vessels behave in a Newtonian physics medium. (Einsteinian relativistic effects are ignored for sanity reasons.)

Contents 1 Setting Up 1.1 Counters 1.2 Record Sheets 1.3 Scale 2 Combat Procedure 2.1 Surprise 2.2 Initiative 2.2.1 Isolated Combat 2.3 Movement 2.3.1 Manoeuvring 2.3.2 Acceleration 2.3.3 Sideslip 2.3.4 Movement Over a Turn

Setting Up

Counters

A generic counter with a unique identifying number is used to specify the location of each unit. Each unit also has a "vector", a smaller counter with the same identifying number, indicating where the unit will move to in the next turn.

Record Sheets

Each unit involved in a starship combat has its own record sheet that is used to identify damage. Per the MTWiki revised combat system, all damage suffered against all objects is on the same scale—in MegaTraveller terms this is the "personal" scale.

A ship's boat, for instance, has a hull rating (Hits) of 275/625, and its various components all have independent ratings as well. This translates to an Integrity of 1100/2500.

Scale

Unlike standard MegaTraveller starship combat with a "flexible" scale, the scale is 60 m per hex. Rounds last six seconds apiece. This allows starship manoeuvring to take place using g-force as a practical measure of acceleration and deceleration. Note that on the whole, this is a much narrower scope than the normal MegaTraveller system, but is also more theatrical from a "what you've seen on television" perspective, a little more frenetic and thrilling (hull points dwindling, crewmen dying, seconds to make a decision... what do you do?), and a little less taxing on suspension of disbelief.

Combat Procedure

Surprise

Roll for surprise as per p.91, Referee's Manual. The same concepts apply.

Initiative

Initiative is rolled as per the RCS, but only the commander of every unit need roll for initiative; all personnel aboard the unit are assumed to take their turns simultaneously with the commander. Most personnel are acting to serve the unit or its weapons and there is little need to go through the busywork of declaring their actions when their actions will continue to be Operate Vehicle, Pass, or Gunner.

Turns proceed in an unusual fashion compared to the MTWiki RCS. Play between units progresses rather similarly to the RCS, although each unit acts as a unified whole when the Taking Turn token passes to the unit commander. Units can seize initiative from one another as usual. An unusual component of this system, however, is the concept of "phases"; at the end of each phase, the cards are returned to their original initiative order and the units can then seize initiative again for the phase. There are two phases: the "movement" phase, and the "attack" phase. After both phases have been resolved, the next turn begins and initiative is rerolled as before.

Isolated Combat

In the rare event that a person is acting independently of the unit—for instance, if someone wants to abandon the ship against orders, or if there are hostile boarders—then a modified procedure is taken. All ships roll for initiative as normal, and seize initiative as needed. Once the "Taking Turn" token passes to that particular unit during the "movement phase", however, all personnel aboard that unit, including the commander, roll for initiative (unless they do not want to act, where they are simply assumed to take their normal actions after all people who wanted to act that round). Then play proceeds through all personnel inside the unit as though the unit itself was the entire play area. Once all personnel aboard the unit have acted, the unit may then move as normal for the turn if a person aboard successfully used the "Operate Vehicle" action. Finally, play proceeds to the next ship in the turn order as usual. Tactics pools are independent on both scales.

Personnel who manage to use the "Operate Vehicle" action allow the unit to perform its movement during the Movement Phase. Personnel who manage to use the "Operate Sensors" action allow the unit to achieve lock-on to one or more enemy targets at the beginning of the Attack Phase. Personnel who manage to use the "Gunner" action allow the unit to perform its attacks against locked-on targets during the Attack Phase.

Technically, this same procedure applies to all forms of independent or hostile activity inside units in a larger battlefield, but it usually only comes up in the starship combat system (and even then only rarely).

Movement

When a unit begins to take its turn, its pilot/navigator will attempt to manoeuvre the unit in one of several ways in order to achieve an advantage over its opponent. No matter what, if a unit's "vector" marker is not near the unit, then the unit must move to the position of the marker at the end of the movement phase.

Manoeuvring

All ships have a pool of manoeuvring points as determined by their drive quality and their size. Spending these manoeuvring points over a given turn is necessary to change the unit's facing, and thereby to change where the unit will produce acceleration and sideslip.

Each manoeuvring point spent changes the facing of the "vector" marker and the unit marker by one hexside. {Illustrated example needed.}

Acceleration

A unit can move the "vector" marker along the facing of the marker by any amount up to the acceleration factor of the unit. The acceleration factor is determined by the g-force rating of the drive installed in the unit, and in the case of military units is usually 6 G.

A unit may only accelerate directly along the facing of its vector marker. A unit cannot "brake", and the only way to slow down is to turn to face the other way and accelerate more. If the unit is moving in a non-straight line, then it must continue to "turn and burn" as appropriate to zero its momentum on all appropriate facings. The sideslip ability described below can reduce some of the pain of this procedure.

Sideslip

In addition to their base ability to accelerate along the facing of the unit, all units also have a sideslip factor that allows them to change the position of their vector marker more directly. A unit has sideslip factors for each the five hexsides excepting the aft hexside, and can adjust the position of its marker a number of times on a given hexside up to the specified sideslip factor.

(Technically a unit can sideslip in one direction, then in the other, with a net result of no movement. Because a unit's position is not updated until the end of the turn, there is no practical purpose for this.)

Movement Over a Turn

No units are repositioned until the end of the movement phase, when all units have taken their movement turns! A unit may freely use sideslip factors, manoeuvring points, and acceleration factors in any order to change the position of its vector marker, provided that the unit does not use more than the number of points its has available.

The facing of a unit's weapons is also determined by its facing at the end of the movement phase, in anticipation of the weapons phase. Thus, a unit must ration its manoeuvring points between changing its vector and ensuring its weapons are brought to bear against the enemy.

The essential concept is that the vector marker determines where the unit will end up at the end of the six-second turn. Units do not actually move at separate times, so there is no way to take advantage of the initiative order to suddenly move close to an enemy unit and discharge weapons at close range; such attacks must be handled through careful attention and anticipation of the enemy's vector changes.