Evolution of the Imperial Star Destroyer

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Simon_Jester
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Re: Evolution of the Imperial Star Destroyer

Post by Simon_Jester »

TC Pilot wrote:
NoogDeNoog wrote:How exactly do you escape a superior force that has you surrounded?
Who said they're surrounded? You yourself provided quotes saying that it was a pincer. That only leaves about.... an infintie number of directions for the Rebel fleet to go.
You do not have to build a physical wall or sphere of units around an enemy to surround them, assuming you are armed with effective ranged weapons. A competently executed 3D pincer movement in a situation like this won't block every angle of approach with a wall of ships, but it will force the fleet to retreat towards one or more enemy battlegroups no matter which direction it tries to run. Imagine, say, four Imperial groups, forming the corners of a cube along with Endor and the Death Star. Or, if that isn't enough, an octahedron or some other shape with many vertices.

To escape in any direction, the Rebels would have to come close to one of the Imperial task forces, allowing the Imperials to drop massive petatonnage on them as they try to get away. So the Rebels would still be screwed even though there are patches of sky they can run towards that do not have an Imperial ship in them, because that still requires them to close with an Imperial force and take the beating from, say, two dozen star destroyers. Especially since the Imperial forces are just as mobile as they are and are quite capable of moving to block their retreat.

The situation is even worse if the Imperials have interdiction ships in-system, and it is implied in the EU that they did. In that case, it is physically impossible for them to escape into hyperspace, and they will have to run a gauntlet of Imperial fire to get away from the Death Star in any direction.
Eleventh Century Remnant wrote:If accurate, that loops back to Simon_Jester's point about the difference between convoy and fleet interdictors. I really do not see a ship as small (600m long, narrow, 1.7 million m3 at a wild ass guess- smaller than an Acclamator) as a Sienar-418 lasting very long in fleet action- a single alpha strike from a Mon Cal starcruiser or a few seconds sustained fire against a manoeuvring target should be enough to remove it as a problem.
Question: what is the radius of hyperspace denial projected by an Immobilizer? In fleet actions, the 418-series may be relying on staying out of effective turbolaser range, to the point where enemy capital ships would have to put out a truly unreasonable effort to get enough power on target to knock the shields down.

Of course, it seems like the Imperial fleet figured out the problem with the design in short order, and commissioned the Interdictor Star Destroyers built on an Imperator hull. The gravity well generators still obscure the main battery, but with full destroyer-grade shielding and power supply, that design would be much better suited for fleet interdictor duty.

If you want the interdictor itself to be a multirole design, of course, there's a lot to be said for compromising the effectiveness of the interdiction in favor of a more effective main battery. But the power consumption of the gravity well generators is high enough that no interdictor design is going to be a full match for other ships in its own tonnage range anyway; high alpha arc throw weight can sanely take second place to other considerations (like maximizing the radius of interdiction, and systems redundancy to prevent the interdictor being unable to carry out its primary function after taking one lucky shot to a single exposed dome).
Think about it; you're trying to stop them escaping- so you divide your forces and scatter them across a wide area, rendering them susceptible to defeat in detail, a thin screen that a concerted Alliance move could achieve local superiority to, blast their way past and escape...eh? How does the original battle plan even make sense, never mind interpretations of it?

Ackbar's retreat would have been such a concerted move, and would not have been bloodless- the starfleet would have reacted to stop them.
My impression is that each of the Imperial task forces pincering the Rebel fleet was individually large enough to handle Imperial intelligence's best guess as to the upper bound of the strength they could deploy for this encounter. And the Imperials seem to have been more or less right about that, too.
Romulan Republic, the motivation is obvious- you are stating the facts as I understand them- but I'm just boggled by the fact that the death star's main reactor was able to power superlaser shots with a YT- sized hole in the shielding; that it even could be capable of generating that much power in the partially completed state it was in. Still, it obviously was.
Is the outer casing (the physical shell that a YT cannot fly through) a necessary condition for the reactor to be online? My impression is that the reactor itself is that (relatively) small installation in the center, and that the large spherical cavity is just a case of distance being the most efficient form of radiation shielding: there's no point in putting anything within three or four kilometers of the reactor housing if you're committed to making the battlestation 900 km across anyway, and making the cavity physically larger reduces the flux of [insert particle of the week here] experienced by each square meter of the chamber.
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Re: Evolution of the Imperial Star Destroyer

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Eleventh Century Remnant wrote:Endor was certainly not a typical battle, but neither was the Clone Wars Battle of Coruscant- and I wonder if there isn't a fleet in being thing happening here. The numbers would seem to suggest that ships are more important than planets; that it's not worth defending a planet if you lose a frigate or better doing it.

Twenty- five thousand (minimum, usual caveats apply) line destroyers- that is to say destroyers that count as a complete line in the order of battle in their own right, nominally Imperator/Imperial class, and counting the variant types I reckon you could add another fifteen thousand to that- and at least a hundred thousand, probably more, light destroyers, Victory-class and the others in the same weight class, as divided across fifty-one million inhabited worlds minimum.

Lose the naval force, and you've lost an enormous proportion of your ability to affect trade between the worlds, and to attack and defend them directly. I know, pot and kettle, analogies, but this really is sounding like the century or so on either side of the Thirty Years War- small professional forces only, much rarer and more important than any non- capital target, and the object of combat is to kill as much of the enemy's fighting strength as possible beause then the territory is ripe.

So, normally, battle is only risked when the odds are or can be manufactured to be in your favour, and potentially losing fights are things to be run away from. I think it may be that only the freak cases like Endor and Coruscant actually result in large pitched battles, when the weaker side has to stand and fight or suffer strategic disaster.

Normative combat may be a running fight, it being fairly obvious to the stronger and weaker party who is which, the weaker side attempting to disengage through hyperspace before they can be destroyed, the stronger party trying to kill the weaker before they can succeed.

At least, thus is theory before pride, stupidity, higher orders and Murphy get involved, and no doubt there are many battles fought that should not have been and more than a few that should not have been but were, but this is the model the respective abundance of ships and planets suggests to me.

In the light of that, and of the false intelligence Palpatine planted about the relatively thin defences of the construction site, the almost kamikaze aspect of Ackbar's mission makes more sense. They were expecting to have to defend against arriving Imperial reinforcements, engage and keep off the fighter- carrying ships that could have spoiled the rebel fighters' precision strike.

Ackbar, not being a fool, made the decision to go ahead with the strike after spotting the Imperial fleet and accept the losses that would be involved, heavy though they would likely be, because the strategic objective was worth the price.

Equally, withdrawing after the death star opened fire would have made hard practical sense. If it was operational to that degree, the primary objective was probably no longer feasible- the sacrifice of ships and beings would be for nothing. Why he listened to Lando is the real mystery.
I will agree with that except for one part. While it might have made hard practical sense to retreat after realizing that the DS was operational, I remember quite distinctly that Lando says "Admiral, we'll never get another chance like this," just as Ackbar is calling for a retreat.

The reason being because as soon as the DSII becomes operational it would be impervious to nearly any Rebel assaults; not to mention that unlike the DSI, the DSII would undoubtedly have a fleet of SDs to protect it as well. So they had no choice but to stick with the fight and hope that the shield generator would be destroyed in time to allow fighters to enter the reactor core and destroy it. The sacrifice of ships that you mention was more than enough to pay the cost of seeing the DSII, and the Emperor himself aboard it, destroyed.
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Re: Evolution of the Imperial Star Destroyer

Post by fractalsponge1 »

Is anything known about the maximum effective range of interdictor gravity well generators? If the range is greater than effective turbolaser range, then interdictors may well stand off from the main action. The EU references to interdictors in the outer system of Endor suggests that the range might be quite long.

It is also worth noting that the grav-well generators on the Dominator are substantially larger than those on an Immobilizer. If this is indicative of greater range or area of effect, then the introduction of ISD-based interdiction platforms might be largely for the benefit of the bigger reactor to power a longer range system. The best defense for such an asset, if possible, is to avoid the fight altogether, and the farther the interdictor can stand off and still trap enemy ships, the better.

In any event, probably the best platform for grav-well generators is on a proper capital ship like a Mandator or Executor, which would have the space and power for them, are the most survivable, and be the ships enemy vessels are most likely to run from anyway.
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Re: Evolution of the Imperial Star Destroyer

Post by Vehrec »

Their range doesn't need to be substantial enough to blockade the inner system entirely and prevent all hyperspace jumps-just any that would be on a viable trajectory out of the system. We really don't know what that involves, and it might be a fairly limited region that can be covered by only a few ships. But that's still probably a large section of the sky to cover, so you do have a good point there.
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Re: Evolution of the Imperial Star Destroyer

Post by Abacus »

Vehrec and Fractal have good points. From re-reading the Thrawn trilogy, it seems that interdicters had two different modes of deploying their hyperspace inhibitors: either in the form of a wide arc, forming a blanket effect, or in the form of a cone that could be directed at the behest of the commander. Thrawn used the latter to set up precise drop points where his ships would come out of hyperspace at the exact point where they were needed and deliver a crushing blow.

As far as the effective distance, that I do not believe will be known unless Lucas himself decides to say, or if they print it in an updated source book. I'd half to assume that it would be at least several light-minutes in distance.

According to the "Revenge of the Sith: Incredible Cross Sections" a Venator-class Star Destroyer had 8 DBY-827 heavy dual turbolaser turrets; each "DBY-827 could hit a target vessel at a range of 10 light minutes" which I assume to be the mid to long (at the edge of effective) range for a Venator. And assuming that their weaponry was upgraded alongside the new class of Imperator/Imperial-class Star Destroyers, the effective turbolaser range could have increased by an extra light minute or two. For a hyperspace inhibitor field, I would assume that it could do fifty times that amount. Just by guestimating.

Also, fractal, the reason I believe that they never fitted the Executor and other large capitol ships with the gravity well generators was because it required too much in the way of manpower, computing, concentration, etc. It filled the roll it was made for. The Executor was a command ship and had the fighting capability to take on a Fleet if it wished. From my experience from the EaW games, it seems like the interdictor would have required to have a halt pattern in space when activating its generators, therefore being a target. I don't think the Empire would be foolish enough to make a ship like the Executor a stopped, painted target for a massed attack. Hence the creation of a smaller, cheaper cruiser that was dedicated to the battlefield role of interdicting escaping enemy ships.
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Re: Evolution of the Imperial Star Destroyer

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The 10-light minute range gives a target a lot of time to dodge; against a planet or a ship with a very predictable path it's perfectly fine, but for a maneuvering target, no chance.

As for Executor, that reason doesn't make much sense to me. The ship is so large and powerful that to support the same crew complement, computing and generating power of one Dominator as an extra system should be trivial. And game mechanics don't count (after all, interdictors can move in Rebellion and still generate a grav well :P ).

The whole point of putting a gravity-well generator on the largest and most dangerous ship is that it's likely to be one of the slowest; that, and the fact that such ships are things that most enemies would likely want to flee from, makes a gravity-well generator equipped star dreadnought a no-brainer, imo. That's one thing the design of the Sovereign and Eclipse got right.
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Re: Evolution of the Imperial Star Destroyer

Post by Eleventh Century Remnant »

There's an obvious problem with that assumption; minutes' travel time for the turbolaser bolts, an impossible targeting problem unless the ship being shot at chooses to commit suicide by being utterly predictable. Might be viable if you can light cone it, arrive, acquire, start firing on a target that won't be aware of your presence until a bare couple of seconds before the bolts hit- if you know where to expect them.

That might have been what Vader intended at Hoth, now I think of it; emerge far enough away not to trip the FTL warning sensors, shoot immediately on emergence- it's a planet, they are fairly predictable- and the first, lightspeed, warning the rebels would have of the fleet would be followed, in far less time than it takes to raise a shield, by the leading edge of the bombardment.

Aganst a target that spots you coming, or one already in system and aware, I strongly suspect the effective- accurate- range in light seconds is no greater than the time, in seconds, it takes the target's captain to give a helm order and have it acted on. Ten, fifteen at the outside, dropping massively for small ships with short chains of command.

Updated sourcebooks, maybe- but as for the old ones, yes, interdictor range was always stated to be much in excess of gun range; especially as they wouldn't actually be trying to hit a point target, just drop an envelope that may be several planetary diameters across- my guess as to what the fluff text for the Interdictor, "simulate a planetary gravity well" from Starships of the Galaxy actually means- over the location of the target.

Fitting grav well generators to a proper capital ship is good for the ship in question, and they should be able to support the burden without much trouble, but considering how relatively few very large capital ships there are it's no great way of adding the capability to the fleet.

I'd still prefer to see decently armed multirole interdictor-destroyers, though. The idea of something that is going to make that important an operational target of itself being unable to fight back just doesn't sit well.
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Re: Evolution of the Imperial Star Destroyer

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fractalsponge1 wrote:The 10-light minute range gives a target a lot of time to dodge; against a planet or a ship with a very predictable path it's perfectly fine, but for a maneuvering target, no chance.

Yeah, I know what you mean. But that's what it says according to the sourcebooks.
As for Executor, that reason doesn't make much sense to me. The ship is so large and powerful that to support the same crew complement, computing and generating power of one Dominator as an extra system should be trivial. And game mechanics don't count (after all, interdictors can move in Rebellion and still generate a grav well :P ).

The whole point of putting a gravity-well generator on the largest and most dangerous ship is that it's likely to be one of the slowest; that, and the fact that such ships are things that most enemies would likely want to flee from, makes a gravity-well generator equipped star dreadnought a no-brainer, imo. That's one thing the design of the Sovereign and Eclipse got right.
Meh. IMO the whole massive dreadnought/supership/ultimate pwning noobz weapon/etc was always a bad idea. Concentrates too many men and resources. Always has sort of design flaw that, once taken advantage of, makes the entire costly contraption to be useless/destroyed. I've always been a big believer in the Thrawn School of Thought; aka I can accomplish the same objective with a less costly avenue of approach.

I do think the Executor was awesome and should have been the last great project after the DSI went boom. It was an effective command ship and from it a competent commander could effectively command an entire sector fleet from it.
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Re: Evolution of the Imperial Star Destroyer

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Abacus wrote:Meh. IMO the whole massive dreadnought/supership/ultimate pwning noobz weapon/etc was always a bad idea. Concentrates too many men and resources. Always has sort of design flaw that, once taken advantage of, makes the entire costly contraption to be useless/destroyed. I've always been a big believer in the Thrawn School of Thought; aka I can accomplish the same objective with a less costly avenue of approach.

I do think the Executor was awesome and should have been the last great project after the DSI went boom. It was an effective command ship and from it a competent commander could effectively command an entire sector fleet from it.
Adding an interdictor well on a ship so its targets can't escape is perfectly logical for a ship that can easily handle it. It's not like it'd be much of an increase in cost either - the Executor is already going to embody several dozen ISD-sized ships at the very least; the cost and resources of a Dominator equivalent is trivial on top of that.

As for adding capability to the whole fleet, I'd agree that a destroyer would be a better candidate for the kind of smuggler/pirate/light rebel hunting the fleet does routinely, but for fleet actions, a grav-well equipped capital ship can't be beat.

There's obviously going to be a point of diminishing returns with large ships, but don't be too quick to dismiss them unless you're sure you know where that inflection point is. At the very least, it comes down to the old truism about battleships - if your enemy has them, you had better have them too, regardless of whether they're the best platform ton-for-ton.
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Re: Evolution of the Imperial Star Destroyer

Post by Eleventh Century Remnant »

As part of the latest chapter of Squelch I had to work this question out, and the numbers I came up with were scary. Big ships should fight in serial; taking on one enemy at a time, obliterating them, moving on to the next. Small ships have to fight in parallel.

At a rough estimate, a single Imperial class destroyer against one of your Bellators, fractal, would need to land better than seventy- five percent of it's firepower on a single shield facing, threatening that specific panel's surge capacity to get a local burnthrough and start doing damage. Not a hope of overloading the radiators.

A Bellator shooting at an Imperator/Imperial class would start overloading radiators regardless of specific location with as little as half a percent of it's fire on target. These figures will vary depending on the estimates you use for shielding, but the capital ship has such an edge in this- size really does matter, and if you're going to go up against big ships, bring a wolfpack. A big one.

The last time we bothered to work this out- as a byproduct of the Executor vs. Mandator thread a couple of pages back- I think we came to the conclusion that the Executor outmassed her escorts by a factor of four hundred and fifty to one.

For open space control operations, locally overwhelming a dispersed enemy fleet, I would actually say that's when heavy vessels come into their own, not in fleet action where they can be met by their weight in smaller, more efficient ships.

Of course, the logistic strain of playing hunter with something that must drink that much fuel is another question entirely.
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Re: Evolution of the Imperial Star Destroyer

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fractalsponge1 wrote:
Abacus wrote:Meh. IMO the whole massive dreadnought/supership/ultimate pwning noobz weapon/etc was always a bad idea. Concentrates too many men and resources. Always has sort of design flaw that, once taken advantage of, makes the entire costly contraption to be useless/destroyed. I've always been a big believer in the Thrawn School of Thought; aka I can accomplish the same objective with a less costly avenue of approach.

I do think the Executor was awesome and should have been the last great project after the DSI went boom. It was an effective command ship and from it a competent commander could effectively command an entire sector fleet from it.
Adding an interdictor well on a ship so its targets can't escape is perfectly logical for a ship that can easily handle it. It's not like it'd be much of an increase in cost either - the Executor is already going to embody several dozen ISD-sized ships at the very least; the cost and resources of a Dominator equivalent is trivial on top of that.

As for adding capability to the whole fleet, I'd agree that a destroyer would be a better candidate for the kind of smuggler/pirate/light rebel hunting the fleet does routinely, but for fleet actions, a grav-well equipped capital ship can't be beat.

There's obviously going to be a point of diminishing returns with large ships, but don't be too quick to dismiss them unless you're sure you know where that inflection point is. At the very least, it comes down to the old truism about battleships - if your enemy has them, you had better have them too, regardless of whether they're the best platform ton-for-ton.
Be that as it may, I'm still of the opinion that they do just fine as a separate ship. But I understand your point of view, even if I don't entirely agree with it.

Out of curiosity fractal, now that I get a good look at that website of yours, how come you haven't ever made a Imperial-class I or II Star Destroyer that builds on all of the improvements that would make it better? As in an Imperial-class III Star Destroyer? I noticed you added a lot of technical and strategic improvements to your Bellator and others, but why not apply that to the ISD? I think that would be interesting to see.
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Re: Evolution of the Imperial Star Destroyer

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I've seen one ISD-III concept courtesy of ECR in the Fanfics section, and it is scary-awesome. I wish I felt up to checking his math, but I don't.
fractalsponge1 wrote:In any event, probably the best platform for grav-well generators is on a proper capital ship like a Mandator or Executor, which would have the space and power for them, are the most survivable, and be the ships enemy vessels are most likely to run from anyway.
True, but these ships are also the smallest in number, and they cannot easily be spared to trawl for enemy warships. Given the sheer internal volume of the large capital ships, it might make sense to mount grav-well generators on them anyway just in case they're needed, but they won't be able to take the place of smaller, cheaper interdiction ships.

Terminology question: I know of at least two classes of ships that use gravity well generators to control hyperspace; I'm using "interdictor" as a generic lower-case name for the class. Does that seem reasonable?
Vehrec wrote:Their range doesn't need to be substantial enough to blockade the inner system entirely and prevent all hyperspace jumps-just any that would be on a viable trajectory out of the system. We really don't know what that involves, and it might be a fairly limited region that can be covered by only a few ships. But that's still probably a large section of the sky to cover, so you do have a good point there.
It's certainly far outside the effective range of light speed weapons; if an interdictor can sit an AU away from the battle and still do its job it's effectively immune to retaliation by normal means. Unless turbolaser fire is drastically superluminal, and I don't remember any evidence for that...
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Re: Evolution of the Imperial Star Destroyer

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Simon_Jester wrote:I've seen one ISD-III concept courtesy of ECR in the Fanfics section, and it is scary-awesome. I wish I felt up to checking his math, but I don't.
Link please? :D
Terminology question: I know of at least two classes of ships that use gravity well generators to control hyperspace; I'm using "interdictor" as a generic lower-case name for the class. Does that seem reasonable?
The official class of the smaller cruiser was the "Immobilizer 418 cruiser" for the Imperial Navy. "Interdictor" was an appellation given to several classes of capital ship capable of generating an interdiction field. So it fits to use the title for either a smaller cruiser, such as the Immobilizer, or for the Interdictor Star Destroyers.
It's certainly far outside the effective range of light speed weapons; if an interdictor can sit an AU away from the battle and still do its job it's effectively immune to retaliation by normal means. Unless turbolaser fire is drastically superluminal, and I don't remember any evidence for that...
There is no evidence. I've looked for I don't know how many uncounted man-hours.
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Re: Evolution of the Imperial Star Destroyer

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Eleventh Century Remnant wrote:As part of the latest chapter of Squelch I had to work this question out, and the numbers I came up with were scary. Big ships should fight in serial; taking on one enemy at a time, obliterating them, moving on to the next. Small ships have to fight in parallel.

At a rough estimate, a single Imperial class destroyer against one of your Bellators, fractal, would need to land better than seventy- five percent of it's firepower on a single shield facing, threatening that specific panel's surge capacity to get a local burnthrough and start doing damage. Not a hope of overloading the radiators.

A Bellator shooting at an Imperator/Imperial class would start overloading radiators regardless of specific location with as little as half a percent of it's fire on target. These figures will vary depending on the estimates you use for shielding, but the capital ship has such an edge in this- size really does matter, and if you're going to go up against big ships, bring a wolfpack. A big one.

The last time we bothered to work this out- as a byproduct of the Executor vs. Mandator thread a couple of pages back- I think we came to the conclusion that the Executor outmassed her escorts by a factor of four hundred and fifty to one.

For open space control operations, locally overwhelming a dispersed enemy fleet, I would actually say that's when heavy vessels come into their own, not in fleet action where they can be met by their weight in smaller, more efficient ships.

Of course, the logistic strain of playing hunter with something that must drink that much fuel is another question entirely.
I was trying to work this out for the star dreadnought I'm finishing up currently. With a 50% hit rate and a mission kill pegged at 10x of alpha in hits landed in one second, the big ship eliminates an alpha-equivalent force of ISDs (400), within 19s. If you assume a dreadnought can manage better than 33% max power dissipation by shields (say if it were a convenient 50%), then the ISD force never threatens total heat dissipation of the big ship's shields.

A lot depends on the strength of individual shield facings, but I would imagine think that individual panel surge capacity scales up with size of the shield system, and total capacity will definitely scale up with radiator size and number.

For one shield facing on the Executor (bridge area), if every known Rebel ship at Endor was firing at maximum, and there are 20-ish ISD equivalents and three Home Ones worth about 10x ISD each, all landing 100% hits (point blank), then the limit is going to be on the order of 100 petatons per second for individual panel failure. At the upper end at least, individual panel strength is distressingly (for a small ship commander) near to average total radiative capacity (assuming it's an Acclamator level %33 of maximum reactor power). Everything of course changes if there are multiple shield layers or a higher dissipation rate, and I for one don't think Executor is, for her size at least (not in aggregate), all that exceptional a warship in many respects.
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Re: Evolution of the Imperial Star Destroyer

Post by fractalsponge1 »

Abacus wrote:Out of curiosity fractal, now that I get a good look at that website of yours, how come you haven't ever made a Imperial-class I or II Star Destroyer that builds on all of the improvements that would make it better? As in an Imperial-class III Star Destroyer? I noticed you added a lot of technical and strategic improvements to your Bellator and others, but why not apply that to the ISD? I think that would be interesting to see.
I think it is bad karma to mess about too much with such an iconic design :). Perhaps someday though.
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Re: Evolution of the Imperial Star Destroyer

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Abacus wrote:
Simon_Jester wrote:I've seen one ISD-III concept courtesy of ECR in the Fanfics section, and it is scary-awesome. I wish I felt up to checking his math, but I don't.
Link please? :D
The titular Hull 721 is in the process of evolving into it; the process is continued in Hull 721, plot arc the second.

I assume ECR has a draft of the design tucked away somewhere, but I've never seen it.
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Re: Evolution of the Imperial Star Destroyer

Post by Transbot9 »

There's obviously going to be a point of diminishing returns with large ships, but don't be too quick to dismiss them unless you're sure you know where that inflection point is. At the very least, it comes down to the old truism about battleships - if your enemy has them, you had better have them too, regardless of whether they're the best platform ton-for-ton.
Didn't work too well in WWII. Oh, sure, both sides had battleships, but it was air power that won the war. Claim Endor was a fluke all you want, but even with the losses taken by the Rebellion the day was won thanks to hot-rodded star fighters (and a small cargo ship modded to be as good as a Starfighter) verses cheaply produced tie fighter/interceptors. It's entirely possible that nobody got into a close-range slugfest like that since the clone wars, and it worked for the Rebellion.

"Build a bigger battleship" is an archaic concept. In fact, there are none operational today. It is either smaller ships with greater firepower (thanks to advancements in ballistic missiles and targeting) or all done by aircraft. Considering how the first Death Star got taken down, how Endor went, and certain facets of New Republic Capitol ships in the EU worked out, the same is paralleled in Star Wars. Heck, Legacy Era has most of the work that over a century before by ISD I & II handled by Ardent class cruisers.
There are only two ways the Federation defeats the empire: Either some hot shot idiot of a captain uses the cosmic undo button known time travel (in a poorly written 2-hour special) to undo however the Empire ended up in the Milky Way, or the leftovers join the rebellion after being horribly crushed to provide them with cannon fodder. The OT plays out like normal with any "federation" support being not even notable enough to get a foot-note in the history books.
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Re: Evolution of the Imperial Star Destroyer

Post by bz249 »

Transbot9 wrote:
There's obviously going to be a point of diminishing returns with large ships, but don't be too quick to dismiss them unless you're sure you know where that inflection point is. At the very least, it comes down to the old truism about battleships - if your enemy has them, you had better have them too, regardless of whether they're the best platform ton-for-ton.
Didn't work too well in WWII. Oh, sure, both sides had battleships, but it was air power that won the war. Claim Endor was a fluke all you want, but even with the losses taken by the Rebellion the day was won thanks to hot-rodded star fighters (and a small cargo ship modded to be as good as a Starfighter) verses cheaply produced tie fighter/interceptors. It's entirely possible that nobody got into a close-range slugfest like that since the clone wars, and it worked for the Rebellion.

"Build a bigger battleship" is an archaic concept. In fact, there are none operational today. It is either smaller ships with greater firepower (thanks to advancements in ballistic missiles and targeting) or all done by aircraft. Considering how the first Death Star got taken down, how Endor went, and certain facets of New Republic Capitol ships in the EU worked out, the same is paralleled in Star Wars. Heck, Legacy Era has most of the work that over a century before by ISD I & II handled by Ardent class cruisers.
Sure things are quite comparable, in space the curvatore of the Universe won't allow battleships to fire more than 40km. Also battleships are restricted to move on 2D planes while starfighters can move in 3D. Also the power of battleship main guns are strictly limited by the curvature of the Universe, so there is an upper limit of weapon power and aircrafts can carry weapons of similar yield.

But about the battle of Endor: it was won, because
- the Emperor died, resulting in chaos
- the Executor was taken out by a golden twinkey (an A-wing hit the bridge, forced the main navigation to a downward maneuver and secondary navigation was not able to take over before hitting the Death Star) killing the commanding staff
- at point blank the kamikaze effect worked for the rebels, they were able to exchange frigates for destroyers but ramming attacks
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Re: Evolution of the Imperial Star Destroyer

Post by Simon_Jester »

In Star Wars, the firepower of individual fighters is a joke compared to that of individual battleships. In real life, aircraft can carry torpedoes or bombs with effects comparable to a 16-inch shell. Combined with their ability to evade air defense fire, that gives them a huge advantage in ton for ton efficiency over battleships. But firepower parity is a prerequisite for that to happen- if all the fighters can do is buzz around outside the battleship's armor and peck away at it with weapons orders of magnitude to weak to penetrate, the battleship wins. And in Star Wars that is the case. Note that a fighter attack was only able to take out Executor after Ackbar concentrated all fire on it, knocking down the shields over the bridge. The fighters did not manage to disable the shields alone.

All the evidence in Star Wars suggests that all sides involved consider capital ships a necessary aspect of the war; the only thing they can't do is fly inside a Death Star superstructure to make precision strikes on its reactor. The fact that that's what is required several times proves little.

Now, the actual size of the capital ships is negotiable- you can go for big destroyer-weight ships like the Imperials, or light destroyers like the Victory class, maybe even smaller. But in any case you're still dealing with what are very much capital ships when compared to the size of "fighters." And compared to the productive capacity of any one ordinary world.
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Re: Evolution of the Imperial Star Destroyer

Post by Eleventh Century Remnant »

Fighters also do not have any great advantage in mobility; the Venator class had 400 'g' straight line acceleration superiority to their own bombers.

And seriously, after Executor lost bridge shielding she was doomed anyway. The next turbolaser bolt to connect would have done the same job, it was just filmic to have someone die heroically in the process- reinforcing the idea that there are diminishing returns in shielding, that the absolute "thickness"- energy handling capability- of the shielding rises with the size of the ship, but in much less than direct proportion to the size of the ship.

Simon, I was actually trying to avoid "As clearly shown in my fanfiction"- but since you mention it, I've basically taken a hint from the British DVLA, vehicle licensing agency, which gives all kit- cars, comedy vehicles like mechanised sofas, and any other extensively modified vehicles out-of-sequence registration numbers featuring the letter Q, not used for any other purpose.

Errant Venture, Black Prince, Emancipator, some of the other radical modifications probably reach that state and qualify, not as Imperator-I or Imperial-II, but as Imperator- Q, side branches of the main development sequence.
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Re: Evolution of the Imperial Star Destroyer

Post by fractalsponge1 »

Transbot9 wrote:snip
Are you being deliberately obtuse?

----------
Eleventh Century Remnant wrote:And seriously, after Executor lost bridge shielding she was doomed anyway. The next turbolaser bolt to connect would have done the same job, it was just filmic to have someone die heroically in the process- reinforcing the idea that there are diminishing returns in shielding, that the absolute "thickness"- energy handling capability- of the shielding rises with the size of the ship, but in much less than direct proportion to the size of the ship.
I'm not entirely sure I agree with it representing diminishing returns in shielding; there doesn't seem to be enough data to quantify that. The entire Rebel fleet concentrated on Executor, and at point blank range on a nearly stationary target it would be a fair assumption to say that they took coordinated shots at key components. That's on the order of 20-50x ISDs worth of firepower, but for an unknown amount of time, required to overload the bridge shield panel.

The situation that allowed the Rebels the chance to do that is not going to happen very often in matchups of large ship vs swarm of smaller ship actions. The swarm needs to take component shots, from as many ships as possible, and as precisely as possible, to hurt the big ship in any meaningful way quickly enough. I'm assuming the disparity in the individual unit comparison is quite large, of course, no fair comparing Allegiance to 4 Tectors or somesuch... In a ranged fight, with unpredictable acceleration and ECM making hits difficult, it's going to be quite difficult for a swarm to manage those precise component shots. It makes it more likely that the damage will average out over multiple panels, and that's not going to be good for the swarm. A big ship fighting another big ship can manage more precise volleys, if only because its component turrets aren't frantically dodging for their lives. Also, the big ship inflicts absolute loss on the swarm with each volley - in a battleship vs battleship scenario, the loser might run with its shields down; in a swarm vs battleship scenario, a battleship that's losing might run having lost its shields, but it might have inflicted a major, irreparable, loss in [/i]destroyed ships on the swarm.

I imagine that large vessels will come into their own in any situation involving a high initial threshhold of damage, because they can survive it and try again without taking permanent losses. Sieges, for example, to crack the outer layer of defense platforms, or mobile warfare, destroying isolated fleets of small ships in detail. When looked at that way, the cost effectiveness equation changes a bit. 100 star destroyers might be cheaper to run overall and per ton than a battleship worth 100 destroyers, but when some objectives cost 25 star destroyers or 99% battleship shield load to achieve, it won't take many battles for the battleship to become cost-effective.
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Re: Evolution of the Imperial Star Destroyer

Post by Transbot9 »

Yes, negligible...much like how a few Y-wings would be worthless against a capital ship. Oh, wait...

And yes, I'm aware that it was Venators that dealt the killing blow, but the bombing run was successful in disabling the ion cannon so that they could deliver the killing blow. Spout the math all you like, but this isn't real science - video footage (not just clone wars, but the movies too) shows that capital ships suck at targeting small objects and fighters are a viable component in capital ship-to-ship combat.
There are only two ways the Federation defeats the empire: Either some hot shot idiot of a captain uses the cosmic undo button known time travel (in a poorly written 2-hour special) to undo however the Empire ended up in the Milky Way, or the leftovers join the rebellion after being horribly crushed to provide them with cannon fodder. The OT plays out like normal with any "federation" support being not even notable enough to get a foot-note in the history books.
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Re: Evolution of the Imperial Star Destroyer

Post by bz249 »

Transbot9 wrote:Yes, negligible...much like how a few Y-wings would be worthless against a capital ship. Oh, wait...

And yes, I'm aware that it was Venators that dealt the killing blow, but the bombing run was successful in disabling the ion cannon so that they could deliver the killing blow. Spout the math all you like, but this isn't real science - video footage (not just clone wars, but the movies too) shows that capital ships suck at targeting small objects and fighters are a viable component in capital ship-to-ship combat.
Yes fighters are almost impossible to shot down, that is why the Millenium Falcon (whatever modifications it have, it still a freighter) destroyed three TIE-s with her quad laser cannons in less than five minutes. Do you think that a star destroyer can not afford the volume to have similar fc hard- and software as the Millenium Falcon?

But you are right fighters are viable component. As recce and fire control aides and of course destroying the other sides recce and fire control aides. That is the normal usage of fighters.
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Re: Evolution of the Imperial Star Destroyer

Post by Fingolfin_Noldor »

If anyone really wanted to spend money on having capital ships killing fighters, there's always the Lancer class frigate. But apparently, it was a rather expensive dedicated vessel, and the Empire didn't build many of them.
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Re: Evolution of the Imperial Star Destroyer

Post by Eleventh Century Remnant »

Ah, combined arms (ish...) I don't think the Lancer's ever been exactly quantified; I gave it a shot, but most of the numbers were based on comparisons and rules of thumb.

I'm not convinced it has the acceleration necessary for it's job, although that might just be stylistic influences talking; the original writeup does explicitly state that "comparable in price to a cruiser, without the added benefits of the larger vessel"- that would be the lower scale cruisers, two hundred to five hundred metres in length, so not massively expensive, just not cost effective.

"Unable to match starfighters for speed or maneuvrability"- which is not a good thing. The one thing a big bulbous ship like that should have is room for a decent powerplant and engine, and if it doesn't, if it isn't built with first- rate power systems and to cope with the stress of high acceleration, why is it so expensive? Sensors and fire control?

That and they have no real ship to ship weaponry. Against a proper small warship like a Carrack or Strike Cruiser, they're dead meat- they just do not have the firepower to hit back with.

Also- if it can't keep up with starfighters, then the chances are it can't keep up with the ships it's supposed to be escorting, either. Imperators are fast; the evidence suggests minimum three thousand, I've always believed that was a minimum and they're at least as fast as the Acclamators, around thirty-five hundred varying a little by variant.

It looks as if the Lancer is a success as far as it's highly specialised role goes, but generally a failure as a ship and as a warship otherwise. If greater antifighter defence is what's needed, the answer is obvious; carry more fighters. (And strip the hulk of every wrecked Lancer you come across for weapon mounts and tracking gear, but that's just me.)

One of the most perplexing things about the Imperial class design for me is just how ground oriented the things are. The drop ships, when you reckon on 22.5m long AT-ATs and their landing barges, and the storage and handling volume required for them- compared to the measly 6.7m TIE Fighter, they take up an enormous amount of room. By volume investment, it starts to look as if the marine detachment was the priority, and the fighter wing something of an afterthought.

Let's run through the list; seventy-two TIE types, initially forty-eight /ln, twelve bomber, twelve boarding craft, later 48 /ln, 24 /sa bomber, subsequently, 48/ln, 12/sa, 12/int Interceptors, final official load 36 /ln, 24 /int, 12 /sa, plus a constant five recon Starwings and an unknown number (five, in parity? Seven to round out a recon squadron? Six in two flights?) of Skiprays.

Eight Lambda shuttles, 20m long but capable of putting up a fight with two fixed, two pivot and one turret sets of twin guns, twelve 38(?)m Sentinels actually better armed and armoured, fifteen 20m ordnance- carrying Stormtrooper Transports, at least one Gamma assault shuttle, an unknown number, ten, twenty-five? of at least twenty-five metre long Theta AT-AT barges- the officially shuttle wing not only outmasses the fighter wing, it may also be able to outfight them.
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