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Does anyone have a solid estimate on the structural and thermal properties of Star Wars durasteel, as compared to the types of steel known to today's metallurgy?

I don't know if that's possible, since (IIRC) structural materials always seem to be combined with structural force fields to maintain integrity.

If so, then one can estimate how strong the combination is, right?

Although if structural force fields are active systems requiring power input... that strikes me as suboptimal engineering.

Simon_Jester wrote:If so, then one can estimate how strong the combination is, right?

Although if structural force fields are active systems requiring power input... that strikes me as suboptimal engineering.

To be be blunt, we will never know. To acquire calculations we use real world materials as low end because we know what the constants are for them.

Simon_Jester wrote: Although if structural force fields are active systems requiring power input... that strikes me as suboptimal engineering.

How so? It would obviously be preferable for the structural members to take the load by their lonesome but if your metallurgy/material physics isn't up to that what is suboptimal about using force fields to augment them? Surely an I-beam that can take the load with forcefield support is better than one that just plain can't period.

Batman wrote:How so? It would obviously be preferable for the structural members to take the load by their lonesome but if your metallurgy/material physics isn't up to that what is suboptimal about using force fields to augment them? Surely an I-beam that can take the load with forcefield support is better than one that just plain can't period.

See here, mostly further down. Relying heavily on active systems to keep your construct from falling apart is a risky game, because the system won't fail gracefully.

Ghost Rider wrote:

Simon_Jester wrote:If so, then one can estimate how strong the combination is, right?
Although if structural force fields are active systems requiring power input... that strikes me as suboptimal engineering.

To be be blunt, we will never know. To acquire calculations we use real world materials as low end because we know what the constants are for them.

To be fair, we can observe accelerations and generate estimates of stress based on assumed masses. You're ultimately right, though; to derive estimates, we have to make some assumptions, and we use real-world materials to get lowball numbers.

An Executor-class ship lay buried and inactive beneath part of the cityscape on Coruscant for years according to the literature, and was not only able to maintain structural integrity throughout this period but actually destroy the overlaying structures in the process of flying itself out. It does not appear that they actually need those "structural integrity fields" to keep their ships together, at least not under conditions up to and including being buried under multi-km skyscrapers for years.

Simon_Jester wrote:

Batman wrote:How so? It would obviously be preferable for the structural members to take the load by their lonesome but if your metallurgy/material physics isn't up to that what is suboptimal about using force fields to augment them? Surely an I-beam that can take the load with forcefield support is better than one that just plain can't period.

See here, mostly further down. Relying heavily on active systems to keep your construct from falling apart is a risky game, because the system won't fail gracefully.

No kidding. That automatically makes it suboptimal engineering how? As I already said OF COURSE it would be decidedly preferable to have your structural supports being able to bear the load on material strength alone. What if they CAN'T? 'Don't build a structure that requires this then' isn't always an option you know.

Where is it stated that imperial vessels use structural integrity fields? I think you're getting Wars and trek mixed up here guys.

Wars ships use particle shielding to enhance their hulls in order to deflect multi-gigaton and multi-teraton warheads, but is there any evidence that they actually need them to hold the ship together?

Simon_Jester wrote:See here, mostly further down. Relying heavily on active systems to keep your construct from falling apart is a risky game, because the system won't fail gracefully.

If it's a choice between that and going into combat in a much weaker, slower ship that your opponent can run rings around, it's worth the risk. Wars technology seems generally more robust and reliable than Trek equivalents anyway, either due to millenia of debugging and refinement, or because Wars engineers actually understand redundancy and safety margins.

Darksider wrote:Where is it stated that imperial vessels use structural integrity fields?

Who knows. There's lines in the TPM ICS which state that the CC-9979 landing ships require the use of powerful 'tensor fields' otherwise the wings would snap, but I can't think of any other explicits uses of the technology.

Consider that a destroyer, under full acceleration, is effectively recieving a continuous multi- teraton kick up the backside; the question is how strong durasteel would have to be to hold the ship together without forcefield support, and the last time I checked- actually was schooled on the subject by Ender- the numbers were not good.

I've searched for the thread once and failed to find it, I'll have another go in a moment, but for the main structural members which must be supporting hundreds of millions of tonnes against accelerations of tens of thousands of metres per second per second, you're looking at something on the same level as Plith- the stuff ringworlds are made out of, yield point close to (if not actually more than) the binding energy of the strong nuclear force.

For normal manoeuvring, the tensor fields might not be necessary. Hell, for flying out from under a few hundred metres of solid rock and a kilometre or three of skyscrapers they don't seem to be necessary. For full normal space thrust and entering hyperspace, for damage tolerance in combat, I'd be very surprised if they weren't essential.



Slightly more reliably, there are hundreds of different grades and compositions of steel for hundreds of different uses, and a variety of processes needed to make them, which means some types of steel cost a lot more than others. Is there any reason not to make the same assumption for durasteel? No-one's going to use warship- structural grade durasteel as speeder chassis (for example), with the associated mass and cost, are they?

Ford Prefect wrote:

Darksider wrote:Where is it stated that imperial vessels use structural integrity fields?

Who knows. There's lines in the TPM ICS which state that the CC-9979 landing ships require the use of powerful 'tensor fields' otherwise the wings would snap, but I can't think of any other explicits uses of the technology.

Those are bolt-on removable wings, though. Those tensor fields could just be big electromagnets.

The other ICSes make mention of tensor fields being used in other starships too (I believe the Venator/Acclmaator use them, but I've got my ICSes packed away currently.)

Edit: Curtis makes several mentions of tensor fields for structural reinforcement purposes of warships and such in his latter post-DK updates I believe.

Double Edit: I think the idea of using tensor fields is not so much to replace the need for highly durable or tough materials (or thick/large members) but more to complement them. Reduce the potential for strain and tear on the ship. That way, if the tensor fields fail, then you still have the hull to hold up (at least temporarily) until the situation can be rectified.

I think the tensor field makes more sense as something you only activate when the ship is under full acceleration. Clearly, these ships don't need tensor fields simply to stay together or even to withstand the stresses of being buried under a city. But one might argue that they are necessary in order to hold the ship together when it's doing something ridiculous, like circumnavigating a planet in one minute. In that case, the reasoning against tensor fields (that they are an extremely unsafe way to design a structure because you can't count on power being up all the time) is inapplicable because you would not be making such maneuvers unless your ship had full power and you are reasonably assured that its important subsystems are operational.

However, one should not make the mistake of assuming that these tensor fields can be treated as an equivalent to Star Trek's annoyingly unscientific "structural integrity fields". They would not have the effect of simulating material strength in every way. It's more like an invisible truss.

Darth Wong wrote:I think the tensor field makes more sense as something you only activate when the ship is under full acceleration. Clearly, these ships don't need tensor fields simply to stay together or even to withstand the stresses of being buried under a city. But one might argue that they are necessary in order to hold the ship together when it's doing something ridiculous, like circumnavigating a planet in one minute. In that case, the reasoning against tensor fields (that they are an extremely unsafe way to design a structure because you can't count on power being up all the time) is inapplicable because you would not be making such maneuvers unless your ship had full power and you are reasonably assured that its important subsystems are operational.

However, one should not make the mistake of assuming that these tensor fields can be treated as an equivalent to Star Trek's annoyingly unscientific "structural integrity fields". They would not have the effect of simulating material strength in every way. It's more like an invisible truss.

Curtis mentioned tensor fields used for other things (like the recoil of ship guns, which is comparable to max acceleration). and you'd probably use them with shields too (against enemy fire, which is going to be of similar magintude to your own.)
I vaguely recall something about tensor fields with black holes and whatnot somewhere too, but I can't remember where he mentioned all this (website I think.)

On the issue of energy consumption, would tensor fields necccesarily consume any energy? I would imagine the same logic that might apply to deflectors might apply to tensor fields too.

Darth Wong wrote: However, one should not make the mistake of assuming that these tensor fields can be treated as an equivalent to Star Trek's annoyingly unscientific "structural integrity fields". They would not have the effect of simulating material strength in every way. It's more like an invisible truss.

This is primarily what was bugging me. Some of the talk in this thread had me thinking that people were headed in this direction and there's just no evidence of that.

Just look at what the Invisible hand was able to withstand despite the fact that it had literally been blasted to shit and ripped in half. If these Tensor fields require power input, they sure as hell weren't operating then. And if SW ships actually required them to maintain structural integrity, wouldn't the ship have disintegrated upon encountering substantial atmospheric friction?
I think it was either Chuck Sonnunburg or Wayne poe who posted an excellent video comparing the crash of the IH to the Ent-D crash in Generations

It was Poe, titled "Another happy landing"

We also have highly varied examples of durasteel qualities, not unlike real steel. This is reasonable given its abundant use. Different applications will require highly different qualities. Structural strength is all good and well, but what if you want a spring? Even structural strength is divided into several different qualities; deformation, fatigue, compression, tension, and shear. Material science is complex, with a long history, and a great but seldom acknowledged impact on the world.

Darksider wrote:This is primarily what was bugging me. Some of the talk in this thread had me thinking that people were headed in this direction and there's just no evidence of that.

Just look at what the Invisible hand was able to withstand despite the fact that it had literally been blasted to shit and ripped in half. If these Tensor fields require power input, they sure as hell weren't operating then.

There was still power to the front section. The ICS shows front and rear reactors, IIRC.


Not that this means tensor fields are required - just that some systems in the Hand could have been powered up right until impact. Certainly the lights were on.

Just as steel can be changed at a molecular level, or processed in certain ways to produce different characteristics, I'd imagine durasteel would be similar. Depending on how the durasteel was made, and what trace impurities are contained within, you'll see different properties.

Case in point: wouldn't the durasteel found in space ships differ from that found in buildings?

In Star Wars: Republic Commando, they mention a special Dwarf Spider Droid that has a completely different hull from the "hummingbird" faced kind seen in Episode 3. The Adviser mentions it's armour is graded for Starship Hulls, and is Indestructable to the weapons the Commandos have except for when aiming for a Contra esque Red dot. Which serves as part of the sensor equipment.

Game mechanics aside, it does support the "varying grade" concept, and other Grades of Durasteel are mentioned periodically throughout the EU. presumably, an AT-AT is built from Starship grade(or close to it) Durasteel (though much thinner) hence it's near immunity to Blaster fire, while an AT-ST, is likely equipped with a far lower grade.

at least that's my understanding of it.

The tensor fields make a great deal of sense on those trade federation LSTs that are stored with the wings detached. It would no doubt allow for a much lighter design that can haul more cargo, and simplified assembly. I can’t recall any other specific use of the fields being mentioned, but I kind of got the impression that they simply pull two points together, that then being some omnipresent field as the Star Trek structural integrity fields are.

The book never stated precisely how tensor fields work, but in the absence of any specific information to the contrary, one might speculate that they simply exert a force on the entire surface (although not necessarily uniform; there might be variation depending on distance from the device). After all, there's no reason to believe that the force is focused like a laser.

However, that's still not at all like Star Trek "structural integrity fields", ie- magic bullshit which simply makes metal stronger in every conceivable aspect (to such an extent that they are sometimes used as a form of combat shielding). A tensor field would be like an invisible truss, not something which makes the metal stronger.