Shields
Shields in Star Trek
Deflector shields or screens these were originally designed to deflect space debris at relativistic speeds. Neither matter nor highly concentrated energy could normally penetrate a shield. When shields were “up,” or energized at a high level, most matter or energy that came into contact with the shields was harmlessly deflected away. When the shields were up, only minor hull damage would be expected during combat. In the 23rd and 24th century. Continuous or extremely powerful energy discharges could progressively dissipate the integrity of a shield to the point of failure. Shields were said to be “holding” if damage was not sufficient enough to allow a compromise; if the shields were “buckling” or “failing,” then a total loss of shield protection was imminent.
Inconsistencies
Shields in star trek are somewhat flexible depending on the requirements of the plot. I take as one of the best canonical examples the final battle in the Undiscoverd Country. The Enterprise takes a pounding and the shields weaken and become leaky before finally collapsing. There are other examples in DS9 but the shields of the Reliant seem to be very weak or very strong depending on the plot. So other video games where there are good implementations of shields are Klingon Academy, Bridge Commander and Starfleet Command. Starfleet Command as it's based on Starfleet Battles tabletop probably gives a good feeling for how a tabletop game should play out. In the TV series there are shield reinforcements used in both TOS and TNG, but as Full Thrust does not have energy allocation it is probably best not to simulate this complexity.
Another option is to track shields strengths for a set of facings so that directional fire will wear down specific shields and not others. Again this is deemed to high a level of abstraction for fleet games and so shields are handled as an omni-directional system.
Shield reinforcement is also a tempting system to model but without energy allocation it doesn't work, there is a way to abstract this using armour discussed later.
A note on design philosophy we are tying to find rules that make sense in a Star Trek setting and not pit ships from other settings with Star Trek ships. If you plan to do that we suggest using Cross Dimensions (XD) as it is designed for this very purpose. This site will cherry pick the best rules for the right feel.
Shields in Full Thrust
The Full Thrust rules cater for screens but these are only effective against beam weapons and at higher ratings are very costly. In Star Trek shields or navigational deflectors which were originally designed to deflect space debris are effective against absorbing damage from most universe weapons. There are exceptions such as Borg cutting beams and enveloping plasma weapons which overwhelm even normal shields. To get the right feel the following rules are proposed to give the feel of the shields leaking damage before buckling and then Wrath of Khan level heavy damage where a torpedo hit will cripple a ship.
Full Trek shields are ablative (shot away bit by bit). Initially, all damage is absorbed by the shields. Score the dice rolls as against an unscreened ship but instead of filling the damage point tracks, record the damage by making “hash marks” in the top right corner of the ship record box (opposite the ID number). Or a custom SSD can have a special shield track can be added like armor.
Once the shields have absorbed damage equal to half their strength, draw a line under the marks; shields are then considered to be at half strength. On subsequent attacks, the shields is buckled and will absorb half damage (continue making marks underneath the line you just drew) while the other half makes it through to the ship itself and is recorded normally. Round odd numbered damage in the shield’s favor, so a ship with half strength shields that gets hit for 3 damage would absorb 2 points with its shields and take 1 point of structural damage.
Once the shields have absorbed damage equal to their strength, they are down and all damage is applied to the damage tracks. Note that the shield generator itself may still be knocked out as a result of threshold checks or needle attacks. (See damage control)
Type Cost Mass Strength
Standard 1 per ship mass 1 per 20 ship mass 1/3 ship mass
Superior 3 per 2 ship mass 1 per 10 ship mass ½ ship mass
Inferior 1 per 2 ship mass 1 per 30 ship mass ¼ ship mass