SW capitalship shields.

[Alyeska]

Here is my take on SW shields, specifically the type used on larger capitalships such as Mon-Cal cruisers or ISDs.

After reading several EU books it becomes immediately clear that shields can recharge fairly quickly. In X-Wing Bacta War a squadron of X-Wings fired a volley at a VSD. This was enough to down its shields. The VSD rolled to present new shields. The fear of the squadron was that the VSD could reestablish its downed shields and represent these. Given the time frame of the battle, that would be a very quick recharge rate on the shields.

Now, with a recharge rate such as this you must strike the shields with more power then the shields can recharge at. This means any weapon not above a certain firepower will never harm a capitalship.

There is a second part to the SW shields. If the weapon goes above a certain threshold it will be powerful enough to completely knock out the shields. Anything above the threshold value allows the remaining energy to slam into the armor. This is how something like an ISD can fire an HTL at a smaller ship. The HTL punches through the shields (possibly knocking it out) and the remaining power slams into the armor.

And now the third aspect of SW shields. If a weapon is below the shield threshold but above the recharge rate, you can still attack the ship. This is how ISDs can fight each other. They attack each other and batter each others shields down until they can cause armor damage.

Here is what all this means. If a ship can produce enough firepower to go above the threshold of the shields, they are doing the most effective damage. Any ship that must batter down another’s shields is actually using more power then the shield threshold. That is because the shield will recharge to a degree. It is entirely possible that a ship can survive twice the shield threshold simply because its recharge rate has allowed it to absorb more firepower. Last of all, any collective weapons fire below the recharge rate will do no damage.

This means that SW ships are fitted with shields based on two concepts. Shield recharge rates and shield threshold values. If your enemy fields lots of smaller guns it would be smarter to use shields with greater recharge. If your enemy fields very large guns in smaller numbers, having a high threshold is a better choice.

Thoughts, comments, suggestions, death threats?

[meNNis]

Death threats... lol... hmmm nah...

I guess it makes sense, sacrifice speed for power or vice-versa. Although I'm sure some almighty person figured this shit out a long time ago... interesting read.

[Mad]

I think shield failure is based on more of an over-stressed model. The way shields fail isn't too consistent, indicating that the generators fail physically.

First, let's take a few quotes, and then work them together:

When overloaded by incoming energy charges, a shield projector's matrix boards will burn out rather than flooding the generator with energy and destroying the entire shield system. Tech crews can repair burned out-out projectors in just a few minutes to get the shields back up to full power.

R2-D2 whistled a warning and shut down the overloaded shield generator to begin an emergency cool off.

Dazed, Luke staggered toward the front of the ship. He barely noticed the sound of enegy bolts, too weak to penetrate the ship's deflectors, exploding harmlessly outside.
...
Another energy bolt struck the freighter forward and was barely shunted aside by its deflectors. The cockpit shuddered violently, and gauges whined in protest at the quantity of energy they were being asked to monitor and compensate for.
...
Another fighter unloosed a barrage on the freighter, only this time the bolt pierced an overloaded screen an actually struck the side of the ship. Though partially deflected, it still carried enough power to blow out a large control panel in the main passageway, sending a rain of sparks and smoke in all directions.

Coolant pump circulates a superfluid with enormous heat capacity to moderate the shield matrix during critical power spikes that cannot be radiated away quickly
...
Shield heat-sink and radiator matrix converts unusable energy surges into heat for disposal

Conventional shield technologies use a range of force-field effects. Ray shield, for example, deflect or break up energy beams, while particle shields forcefully retard high-velocity projectiles. Normally, shield intensities diminish gradually with distance from the generator or projector. However, shields projected in an atmosphere tend to have a defined outer surface. Such a boundary becomes super-hot when left still, and mirage like affects are seen. Shields surrounding a moving airborne vessel are less visible, but can impact aerodynamic performance.

Okay, so shields absorb or redirect incoming energy. This energy is converted into heat, which is likely dissipated at the rating given for the shpis in ICS2 (one ship has a higher shield rating than reactor rating, indicating that this isn't the power being used by the shield system). If the energy comes in quicker than the system can dissipate it, then things overheat until the projectors or generators burn out. As the ANH quote show, shields are an active system, which "monitor and compensate" for incoming energy, instead of being a passive wall that can be nibbled away at.

Bleedthrough occurs if the shields have to absorb too much energy at any given instant. Even relatively weak weapons can have bleedthrough if the wattage is high enough. Of course, bleedthrough from weak weapons won't do much damage. This threshold is probably determined at least some by how much power is directed to the shields. If a ship puts a lot of power to the shields, then more energy can be redirected (and heat may be dissipated faster, depending on the process).

A lot of small bleedthrough instances can probably take their toll on the shield equipment, basically causing a slow death from lots of small power spikes.

Typically, we see shields begin to become less effective (overheating), sometimes accompanied by bleedthrough, then a sudden collapse (burn-out or shutdown). Soon afterwards, if the ship survives, shields are back online (replaced projectors or they are brought back online after cooling off).

There isn't much support for a linear degredation of shields. Usually, the effects are pretty random. In Rogue Squadron, for instance, an assault on a planetary shield was slackened off as the shield radius shrank because the shields were expected to simply collapse at any time, but when that time would be couldn't be calculated. This seems more consistent with equipment failure than an energy reserve that's slowly being nibbled away.

[Illuminatus Primus]

Mad seems to cover everything. ICS2 precisely informs us that there's a specific shield wattage dissipation threshold--so Alyeska is definitely right--a weapon below a certain wattage will never do any damage to the shield. Alternatively--many simultaneous strikes by lower-wattage weapons will breach the threshold--fighter warheads used on lighter capships are a good example.

[His Divine Shadow]

Indeed, the whole process seems very random, based on many factors of which we probasbly do not know all yet.
Bleedthrough sometimes occur without shield failure too it seems.

[SPOOFE]

Then there's the whole "swiss cheese" effect, where tiny whole open up in a shield before it's completely collapsed.

I'm willing to bet that deflector shields can be selected to mimic variable hardnesses and brittleness, depending on the situation. I don't know what the advantages or disadvantages of doing so would be, though. I'm betting a harder, less forgiving shield surface would work better against numerous smaller impacts, though make the shield itself more prone to bleedthrough effects. Conversely,a softer, malleable surface would absorb larger hits better (gives the shield more time to dissipate the energy).

Though I should spend more time thinking on this, because we've seen examples of both hard and soft shields (in the X-wing series, we primarily saw hard shields, while in the Black Fleet Crisis, we get descriptions of shield spheres shrinking under impacts).

[Darth Garden Gnome]

Additionally, shields are able to absorb and re-direct energy from blasts into their own systems, given that it is a small enough blast. From "Lando Calrissian and the Flamewind of Osseon":

"pg.218: A pair of fighters streraked by, spitting fire. The Falcon's shields glowed and pulsed, absorbing the energy, feeding it into the reactors. There were limits to the amount that could be absorbed that way - in which case the reactor would come apart, taking the ship and everything within a thousand kilometers with it - but for now, each unsuccessful pass fed the Millenium Falcon's engines and her guns."

Courtesy of Wayne Poe's database of quotes.

[Illuminatus Primus]

Then there's the whole "swiss cheese" effect, where tiny whole open up in a shield before it's completely collapsed.

This just appears to be an example of shield-bleedthrough.

while in the Black Fleet Crisis, we get descriptions of shield spheres shrinking under impacts).

Its possible that the decreasing region of shield affect according to AOTC shrinks with shield overheating/increasing inability to dissipate waste energy.