StarDestroyer.Net BBS

Another dropship type used by the Empire would be the F7 Landing Brick, although it only carries 40 troops.

PhilosopherOfSorts wrote:Possibly, but you are also more exposed in orbit, not much to hide behind up there after all. At a lower altitude you can use the terrain as cover, or at least concealment. That big honkin' ion cannon can't do much to you if it can't target you because there's a mountain in the way.

Well, this being Star Wars weaponry we're talking about, and since we are naturally using SD.net calculations of weapon power... frankly, all they need to do is shoot twice. Which still beats only needing to shoot once, I guess.

Eleventh Century Remnant wrote:And yes, they almost certainly do come down on repulsors for the most part. Only in emergency would it be necessary to decend on ions; it can't possibly be routine, and the terrain of the battle of geonosis was not lava plain, which is a bit of a giveaway. I wanted to point out that in the event that a ship does have to resort to lithobraking, ("slowing down by slamming into the ground"), in this case the ground might actually lose. They certainly have nothing to fear from the atmosphere.

Oh, sure, but it can't be good for the ship. Or the crew. Given the sheer brute strength of the ship's force fields, it's quite possible for it to make an atmospheric reentry and plow into the ground without being destroyed (didn't Anakin and Obi-Wan ride half of a crippled CIS destroyer down in Episode III)?

Even so, it's a very suboptimal way of putting troops on the ground. For starters, you don't have all that much control over your final position or landing attitude. The ship may do just fine canted at five or ten degrees to the horizon... but that's a problem from Hell for infantry or walkers trying to disembark. And it's entirely possible that you'll wind up well out of place if you missed a minor detail of the terrain.

On top of that, taking a ship without landing gear in for a skid is problematic, because you can't steer effectively. Star Destroyers have a keel, for crying out loud; try to lithobrake on that and there's a real chance the ship will turn broadside and go into a roll.* That's going to have effects inside the hull that will be tough to suppress for using shielding/tensor fields/inertial compensators/whatever.

Lithobraking might work in the sense that everyone reaches the planetary surface alive, but it's a really weird, and probably bad, way to plan a spaceborne assault. It's the sort of thing Black Prince** might do in a truly strange and desperate scenario, but there's no way it would be SOP for an entire ship class.
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*The image of an Imperator class star destroyer rolling around its long axis as it tumbles to a halt on the ground is... impressive.
**Reference to ECR's series of Star Wars fan fiction threads, for anyone who doesn't get it.

NoogDeNoog wrote: In the Hutt Gambit, the slaver ship that is corellian corvette, 150 meters long, has to take on slaves at the space station in orbit

Corvettes certainly can land on planets. Thy do so on in the Novel Wraith Squadron and also in that obscure and little known source; Episode III: Revenge Of The Sith

Corellian CR-90 corvette?

Chances are, there's going to be a doctrinal balance between freely blowing through bits of the planet to get at the defenders, and not blowing through too many because you want the planet in useful shape.

When you can melt mountains and scatter them through the upper atmosphere, climatic damage may actually be a serious concern. (Climactic damage would be something else entirely, see; Alderaan.)

I wonder if this is the reason that, apart from some of the heavy blaster artillery, we seldom see ground vehicles with decent power to weight? A Corellian Corvette, for instance, should be putting out firepower in the 100mt/sec range; four guns, comparable to a known weapon type throwing 5 bolts/second at 6 mt, plus lighter weapons. An AT-AT is rather larger than one percent of a Corvette, and apart from the 'maximum firepower' shot on the shield generators doesn't even deliver within two orders of magnitude of that.

Generations, probably millennia old conventions of war skewing the available technology, that the clone wars only began the process of tearing up?


"Lithobraking" is a joke. It was a running gag back in the days when I used to play tabletop games that involved drop pods and the like, and it was what was said when you miscalculated hideously and crashed in a ball of flame. It's an obvious pun on aerobraking, and a radical, dynamic new insertion technique, honest. In other words, cocking it up then trying to recover some dignity by pretending you meant it that way.

The fact that some Imperial dropships can say that and mean it, that demolishing the outworks of a fortress by slamming into it with an assault boat at a round number of KPS then disembarking to fight your way in may actually be feasible, is genuinely frightening.

Probably not worth it with a big ship, though.

And is a 17km-wide flying saucer, easily comparable with the Executor of the same film. It has to actually have some sort of repulsor-support to even stay afloat, ergo these things exist for ships of this size.

Yes, but it does not have to RENTER an atmosphere which is where all the stress of atmospheric operation is coming from. I can put a 747 on a carrier deck and it will be fine, just don't expect it to take off from it or land on it.

Well, we don't know the exact construction of these kinds of space stations. If there's mobile construction platforms involved with supplies coming down piece by piece or if the whole thing's done in space and then sunken into the atmosphere. Either way, it has to be equipped with engines to stay afloat in an atmosphere, so we know these kinds of vessels can do it from that very obvious example. And as stated, the Executor was preparing to enter the atmosphere of Krake's Planet in Marvel 63, even sending landing requirements to the base. (I assume not actually landing, but clearing an area for hovering).

Patroklos wrote:

And is a 17km-wide flying saucer, easily comparable with the Executor of the same film. It has to actually have some sort of repulsor-support to even stay afloat, ergo these things exist for ships of this size.

Yes, but it does not have to RENTER an atmosphere which is where all the stress of atmospheric operation is coming from. I can put a 747 on a carrier deck and it will be fine, just don't expect it to take off from it or land on it.

What are you talking about? Full-sized starships can pull 3000+g accelerations, and take teraton-yield point explosions on their shields, and you're saying they somehow cannot handle the acceleration and heat of reentry and exit from atmosphere? Never mind that a little TIE fighter can manage it, and LAAT/i's in the Clone Wars cartoons do deployments from low orbit.

Eleventh Century Remnant wrote:I wonder if this is the reason that, apart from some of the heavy blaster artillery, we seldom see ground vehicles with decent power to weight? A Corellian Corvette, for instance, should be putting out firepower in the 100mt/sec range; four guns, comparable to a known weapon type throwing 5 bolts/second at 6 mt, plus lighter weapons. An AT-AT is rather larger than one percent of a Corvette, and apart from the 'maximum firepower' shot on the shield generators doesn't even deliver within two orders of magnitude of that.

Everywhere else on the Internet, but not here, we'd be getting people arguing that the space-based firepower calculations are overrated.

Here, I all I have to suggest is atmospherics. Fire a megaton-range energy weapon in atmosphere and weird things can happen- notably, it's bad for any infantry or light walkers in the vicinity, even if properly shielded hovertanks/heavy walkers can handle the side scatter.

"Lithobraking" is a joke...

Yes, but it's as good a name as any for trying to come to a stop by a deliberate crash landing.

Patroklos wrote:Yes, but it does not have to RENTER an atmosphere which is where all the stress of atmospheric operation is coming from. I can put a 747 on a carrier deck and it will be fine, just don't expect it to take off from it or land on it.

Strictly speaking, a ship with repulsorlifts capable of 1g or better acceleration doesn't have to reenter; it can just drift into the atmosphere slowly at very suborbital speeds. Reentry happens because you were travelling at orbital speed when you hit the upper atmosphere and have several thousand kilometers per hour of velocity to shed.

fractalsponge1 wrote:

Patroklos wrote:

And is a 17km-wide flying saucer, easily comparable with the Executor of the same film. It has to actually have some sort of repulsor-support to even stay afloat, ergo these things exist for ships of this size.

Yes, but it does not have to RENTER an atmosphere which is where all the stress of atmospheric operation is coming from. I can put a 747 on a carrier deck and it will be fine, just don't expect it to take off from it or land on it.

What are you talking about? Full-sized starships can pull 3000+g accelerations, and take teraton-yield point explosions on their shields, and you're saying they somehow cannot handle the acceleration and heat of reentry and exit from atmosphere? Never mind that a little TIE fighter can manage it, and LAAT/i's in the Clone Wars cartoons do deployments from low orbit.

If you dont want to boil the planetary atmosphere, or blew it away with your ion engines (or at minimum turn some spots on the planet into a radioactive wasteland) then "reentry" is a tricky thing to do. There are reasons to have three different type of engines in SW. So in the atmosphere there is no 3000g acceleration...

On the other hand with repulsors aerobraking is unneccesary so the heat of reentry can totally be avoided if one wishes.

The reason the Corellian Corvette had to dock with the space station to take on slaves in the Paradise Snare was that Ylesia's atmosphere was constantly stormy and very turbulent, necessitating smaller craft with preferably human pilots.

As far as Destroyers and SSD's in the atmosphere, does the escape of Lusankya in Krytos trap count as canon? As I recall, its ascent killed massive numbers of people when it shot its way free, rather than any ignition of the engines. It also had a massive repulsorlift cradle to take it into orbit. So, Capable of operating once (with a specially designed system,) yet it did not pose a significant danger to Coruscant itself.

DrMckay wrote:The reason the Corellian Corvette had to dock with the space station to take on slaves in the Paradise Snare was that Ylesia's atmosphere was constantly stormy and very turbulent, necessitating smaller craft with preferably human pilots.

As far as Destroyers and SSD's in the atmosphere, does the escape of Lusankya in Krytos trap count as canon? As I recall, its ascent killed massive numbers of people when it shot its way free, rather than any ignition of the engines. It also had a massive repulsorlift cradle to take it into orbit. So, Capable of operating once (with a specially designed system,) yet it did not pose a significant danger to Coruscant itself.

Since it is the same series where solar mirrors broke through the shield of Coruscant (with energy output almost reaching as of a light turbolaser bolt)...

bz249 wrote:Yes, but it does not have to RENTER an atmosphere which is where all the stress of atmospheric operation is coming from.

On the other hand with repulsors aerobraking is unneccesary so the heat of reentry can totally be avoided if one wishes.

You're still going on about barriers to atmospheric entry like heat being a limit to the ships themselves; how much energy do you think atmospheric friction represents? Wanna bet it's enough to overwhelm SW capital shielding?

People have already said that there are tactical and practical reasons not to use ion drive in atmosphere, it does not mean you can't do it. All the "stress" you're talking about hardly concerns the ship itself.

fractalsponge1 wrote:

bz249 wrote:Yes, but it does not have to RENTER an atmosphere which is where all the stress of atmospheric operation is coming from.

On the other hand with repulsors aerobraking is unneccesary so the heat of reentry can totally be avoided if one wishes.

You're still going on about barriers to atmospheric entry like heat being a limit to the ships themselves; how much energy do you think atmospheric friction represents? Wanna bet it's enough to overwhelm SW capital shielding?

People have already said that there are tactical and practical reasons not to use ion drive in atmosphere, it does not mean you can't do it. All the "stress" you're talking about hardly concerns the ship itself.

I did not use the stress in the physical sense, but as a pschychological one. A big ship can cause lots of trouble to the planet, so they have to be extremly careful there. Imagine like maneuvering with an oceagoing vessel in a harbor... it is one of the most difficult part of navigation. I can say a stressful one.

By the way friction plays a very minor role in atmospheric reenty heat. It is the adiabatic compression of air which causes the heat buildup.

bz249 wrote:I did not use the stress in the physical sense, but as a pschychological one. A big ship can cause lots of trouble to the planet, so they have to be extremly careful there. Imagine like maneuvering with an oceagoing vessel in a harbor... it is one of the most difficult part of navigation. I can say a stressful one.

Better

Again, not arguing that such an entry would be bad for the planet, just saying there's not really much of a limitation on the ships themselves. Heat buildup in atmosphere is only going to equal how much energy the engines are putting out to bring the ship down (assuming only ion drive), and most of that heat does not go to the ship. Acclamator shielding can dissipate 1/3rd reactor output; that leaves a big margin for what the ship can theoretically do in atmosphere.

What are you talking about? Full-sized starships can pull 3000+g accelerations, and take teraton-yield point explosions on their shields, and you're saying they somehow cannot handle the acceleration and heat of reentry and exit from atmosphere? Never mind that a little TIE fighter can manage it, and LAAT/i's in the Clone Wars cartoons do deployments from low orbit.

You are assuming a great many things, the most absurd is that every ship can be readily designed to withstand every kind of stress from every source optimally. It doesn't really matter how much acceleration a vessel can withstand when in a vacuum because the design of a ship to withstand those stresses in a vacuum would be completely different than one designed to withstand the same stresses in an atmosphere. It is really no differned than expecting a current fighter jet to somhow operate effectively as a submarine at the same time. On top of that direction matters. A fighter jet can withstand extreme acceleration forward, but if I tried accelerate it in any other direction it would fall apart. Starships would be no different, being designed to support the acceleration (and generally predictable) from its engines in the expected direction only, anything more would be a waste.

You guys are also gold plating as well, pretending that every ship can have every engine type. It very well may be that a vessel designed primarily for space combat (Executor) didn't have its cababilities watered down by having a comblete set of repulsor engines in addition to its optimally equiped space based ion engines. It would be like putting helicopter roters on a race car. It would make sense for a vessel like a Correllian Corvette, however, designed to be a jack of all trades to make those compromises.

The fact that Lusankya needed a repulor craddle to get into orbit should make it clear that the design itself was not meant to opperate inside the atmosphere independantly. This would also explain things like Bespin if we insist it must be an orbital constuction. There are simply specialized methods to get very large objects from orbit to the surface if required of visa versa. Which of course is exactly what we do now in real life.

[quote="DrMckay"]The reason the Corellian Corvette had to dock with the space station to take on slaves in the Paradise Snare was that Ylesia's atmosphere was constantly stormy and very turbulent, necessitating smaller craft with preferably human pilots.

Wait, I thought these ships were so powerful that atmosphere wouldn't bother them at all. wouldn't if be easier to take a larger ship through rough atmosphere than a small one?

I finally found a pic of a Cr-90 with landing gear.

http://www.roleplayersdirect.com/downlo ... _D6Con.pdf

How can this be, even if they had landing gear, the main part of the hull is at least 15 -20 meters off the ground. It must have an incredible cargo ramp.

No one answered my question before. If these ship are meant to routinely land on planets, wouldn't it be easier to build them on the planets? Why do they have shipyards in space???

No one answered my question before. If these ship are meant to routinely land on planets, wouldn't it be easier to build them on the planets? Why do they have shipyards in space???

It is easier to build large objects in zero gravity for obvious reasons.

NoogDeNoog wrote:No one answered my question before. If these ship are meant to routinely land on planets, wouldn't it be easier to build them on the planets? Why do they have shipyards in space???

This does not necessarily follow. For example, one advantage of construction in vacuum is that you can control the working environment. Another is that the default is near-zero gravity. These make things difficult for human workers, but the vast majority of work with air-sensitive parts could be carried out by non-air breathers or droids. Meanwhile, microgravity makes it easier to build areas that will have different orientations when the artificial gravity is turned on (such as the Millenium Falcon's turrets). Furthermore, industrial accidents are less deadly in vacuum, without an atmosphere or water to carry any toxic chemicals they work with, and without shockwaves or fireballs from any munitions accidents. So, to sum things up, there are a number of potential reasons why Star Wars civilizations use vacuum for starship construction, which are totally unrelated to those finished ships' ability to enter and maneuver in atmosphere.

EDIT: Well, here are some of the less obvious reasons.

I guess its kind of like asking is it easier to build a 3D model in real life or via a computer program.

Through a turbulent atmosphere on repulsors? I can actually see a problem there- depends how well the repulsors anchor the ship to the centre of mass, how effectively they prevent lateral movement that doesn't involve a change of gravitational potential energy.

Obviously well enough for routine operations on habitable worlds, but on a 'Hot Jupiter', say, with an enormous atmospheric envelope and so much energy being pounded into it, you are going to get weather patterns that make a present- day yield nuclear blast wave look minimalist.

With the raw thrust available from ion drive, yes, bull on through, but with an inherently weak force which gravity is, I think there may be a legitimate problem there trying to negociate something like that on repulsors. Of course, that's probably one of the cases where environmental damage doesn't matter a damn. And there may be very little reason (barring really extreme sports) to go there anyway.

All right, never mind the extreme case. Ylesia. Blue-green, looks pleasant enough, but it has a rotation period of ten hours, and at least one moon- I have to admit I don't get it. With that kind of weather problem, enough to punch a starship around- but too much of an ecology to go burning holes in the atmosphere on ion drive- shouldn't that be compromising it's habitability?

Actually, probably not. Not considering the survival tools a spacefaring civilisation should be able to bear on the problem. Which means that you can comfortably set up shop on planets that have environment issues severe enough to cause problems for relatively weak gravitic drives- and too much environment to go spraying the air with ion beams, which is a good way to ionise it and get it moving, causing environmental issues, as any I can think of at the moment. Repulsors might be the weak link in the chain here. Anyone want to start a beanstalk firm?

Shipyards in space- that one's likely a habitability issue too, through pollution. Not carbon based, I don't see much deliberate combustion happening here, but in the foundry and assembly processes there is probably going to be some chemical and heavy metal residue, highly energetic and highly toxic. Corellia's virtually a garden world- precisely because they made the decision, generations ago, to move the industrial base up to orbit and preserve the ecology.

(Take too long to retype it all, "a new post has been made to this topic" grumblegrumblemuttergrumble, but Bakustra's got a point there.)

For building - most of the resources consumed by the really massive yards would not come from the planets themselves. (Kuat and Corellia, for example) If most of the construction material and components will be coming from other systems via hyperspace, it makes much more sense to refine/process/assemble them in orbit rather than pulling the material down the gravity well and back up again.

You are assuming a great many things, the most absurd is that every ship can be readily designed to withstand every kind of stress from every source optimally. It doesn't really matter how much acceleration a vessel can withstand when in a vacuum because the design of a ship to withstand those stresses in a vacuum would be completely different than one designed to withstand the same stresses in an atmosphere.

It is really no differned than expecting a current fighter jet to somhow operate effectively as a submarine at the same time. On top of that direction matters. A fighter jet can withstand extreme acceleration forward, but if I tried accelerate it in any other direction it would fall apart. Starships would be no different, being designed to support the acceleration (and generally predictable) from its engines in the expected direction only, anything more would be a waste.

Of course it would not be optimal, but that does not mean it would not be easily feasible. Did I ever say ships need to pull 3000g in atmosphere? How much acceleration do you need to manage a controlled touch down on a planet? double-digit multiples of g? You're saying a ship with structure rated for maneuvering in the 3000g+ range can't handle single or double digit g in atmosphere? The Invisible Hand, in ROTS, lost primary engine power (by virtue of being separated from its ion drive) and did a free-fall into the gravity well, and survived largely intact. Venators and Acclamators routinely enter and leave gravity wells. The structure of warships also need to handle high local momentum transfer from their heavy turbolasers.

You guys are also gold plating as well, pretending that every ship can have every engine type. It very well may be that a vessel designed primarily for space combat (Executor) didn't have its cababilities watered down by having a comblete set of repulsor engines in addition to its optimally equiped space based ion engines. It would be like putting helicopter roters on a race car. It would make sense for a vessel like a Correllian Corvette, however, designed to be a jack of all trades to make those compromises.

Source, for where it says repulsorlift drives are expensive, structurally cumbersome/unfeasible, and not nearly universal? If there is one, I'd really like to know.

Venators, optimized as space carriers and flotilla vessels, have repulsorlifts perfect suitable for atmospheric operation. Much more space and power constrained craft like starfighters have them, after all. Even TIEs (unless you want to argue all the maneuvering in Bespin's atmosphere was done on ion drive and dependent on the innate aerodynamics of the fuselage).

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NoogDeNoog wrote:

It is easier to build large objects in zero gravity for obvious reasons.

Isn't the obvious reason that the vessels are too large to get them into space in one piece.

That is not the obvious nor the only reason to be honest. It's one of them but there are problems of materials transport, movement, and even space of the object on terrestial settings. Getting them into space is usually the last problem one runs into.