Starfleet Jedi

This could go in Other Websites, since it was inspired by my peeking at Vince's page about Star Wars starship densities where he uses my volume figures without attribution and tries to claim that Star Destroyers are 25 times more dense than water, but I think it belongs here . . . I'm just not converting the entire thing over to the phpBB format.

http://dsg2k.blogspot.com/2014/05/sinking-ships.html

To summarize, the velocity of an engine sinking on Mon Calamari in "Gungan Attack"[TCW4] pegs Star Wars vessel densities as topping out somewhere in the neighborhood of water's density, and they could very well be less. 750kg/m^3 is safe enough to use as a single figure, though 1000 might get less argument from some quarters. 25,000 is right out.

To give it as a shorter version, you can calculate terminal velocity even in water by solving for the square root of ((2*m*g)/(ρ*A*C)) provided you correct for buoyancy . . . but we had the velocity. And, since we know some things about the size of the engine and could guess at a drag coefficient, gravity, and the density of the Mon Calamari ocean, we could then get the mass.

Since we had the mass and know the approximate volume of the engine, we have density.

There is one small problem in that the final scene of the engine parts hitting bottom shows them going five times faster than they were previously, but this is explainable as fast-motion (i.e. the opposite of slow-motion). After all, there's no way the folks could've been hanging on to the engine if it were going that fast the whole time or accelerating to that speed, because the final speed shown would've required that Senator Padme Amidala be strong enough to hold 120 people who are hanging on to her while she hangs on to a rail with her hands.

So, amusingly enough, the canon came back and reinforced my old guess on the Volumetrics page where I had it at 500 to 1000 kg/m^3, which makes so much sense given hydrofoamed permacrete and other weight-saving measures known to exist in Star Wars Awesome.

Here's Vince's video on Youtube for those interested:

https://www.youtube.com/watch?v=wKj_e7ZmBhI

So, them ships are made of cloudfoam?

I'm sure the inflationists would think that of the findings.

But really, for an engine assembly to have that density (and which we can presume to hold for the rest of the ship, though I would expect engines to be more dense) is not so far from our current techniques as to be beyond the pale. Oh, I don't mean that we build spacecraft that way, but it's not too far from what one might expect at a shipyard. After all, these things don't have to float . . . obviously.

And that really fits in with the Star Wars realism perspective that was prevalent before the inflationists got cracking. After all, the old Shane Johnson tech manual describes titanium-reinforced hulls. The TPM novelization refers to Coruscant as steel alloys and glass. The ascension cables were steel-clawed. The ANH script refers to the door sealing the chasm that Luke and Leia swing over as steel. The ANH novelization refers to the Death Star exterior as steel. The RotJ novelization refers to Boba as "steel-masked" and Luke's hand as being made of steel. The floor of the Emperor's room in the Death Star is made of steel. The Imperial shuttle has a "steely hull", and its landing ramp is described as chilly steel. The bunker corridors are made of steel. Melted steel floats amongst the debris of the final battle.

And, of course, there's the hydrofoamed permacrete and other weight-saving measures of that nature as I've mentioned before and will mention repeatedly.

Put simply, all that neutronium and hyperdense nonsense was never a good idea when compared to the canon itself. The canon supports Star Wars realism, not inflationism.

2046 wrote:I'm sure the inflationists would think that of the findings.

But really, for an engine assembly to have that density (and which we can presume to hold for the rest of the ship, though I would expect engines to be more dense) is not so far from our current techniques as to be beyond the pale. Oh, I don't mean that we build spacecraft that way, but it's not too far from what one might expect at a shipyard. After all, these things don't have to float . . . obviously.

And that really fits in with the Star Wars realism perspective that was prevalent before the inflationists got cracking. After all, the old Shane Johnson tech manual describes titanium-reinforced hulls. The TPM novelization refers to Coruscant as steel alloys and glass. The ascension cables were steel-clawed. The ANH script refers to the door sealing the chasm that Luke and Leia swing over as steel. The ANH novelization refers to the Death Star exterior as steel. The RotJ novelization refers to Boba as "steel-masked" and Luke's hand as being made of steel. The floor of the Emperor's room in the Death Star is made of steel. The Imperial shuttle has a "steely hull", and its landing ramp is described as chilly steel. The bunker corridors are made of steel. Melted steel floats amongst the debris of the final battle.

And, of course, there's the hydrofoamed permacrete and other weight-saving measures of that nature as I've mentioned before and will mention repeatedly.

Put simply, all that neutronium and hyperdense nonsense was never a good idea when compared to the canon itself. The canon supports Star Wars realism, not inflationism.

Being light weight and being weak are not synonymous with one another.
http://en.wikipedia.org/wiki/Ultralight_material
http://en.wikipedia.org/wiki/Aerogel
http://en.wikipedia.org/wiki/Aerographite
http://en.wikipedia.org/wiki/Aerographene
http://en.wikipedia.org/wiki/Metallic_microlattice
http://en.wikipedia.org/wiki/Metallic_foam

It kind of explains why Star Wars ships seemingly float on air so readily. We can already make materials where the densest part is literally the air at sea level.

Oh, very much so. I recall Wong dismissing nanotechnology on the grounds that carbon fiber is just carbon and won't get magical properties, or somesuch silly claim, but the fact is that the inflationism on density was silly even just on scientific grounds. It isn't necessary to always have the biggest number. I would rather have light materials that can actually be worked with and don't require a crane to pull up a deckplate.

Saturday, May 31, 2014
Star Wars Fuel and Densities

No, this is not a comprehensive post . . . just a note from the TCW novelization, Ch. 16 and 17, which is when the newly-acquired Twilight, no longer trying to get aboard the Republic Attack Cruiser within Teth's atmosphere, is instead going to try to make it on her own.

Ch. 16: Even at maximum thrust, the Twilight climbed slowly for a pilot used to starfighters. [...] The freighter shuddered as it climbed. [...] He tweaked the fuel injectors a little higher.

Ch. 17: "I can't outrun them," he said. [...]
"Let's jettison something," Ahsoka said at last.
Laser cannonfire streaked past the Twilight's nose, and another vulture droid buzzed the ship, so close to the cockpit viewport that Anakin jerked hard to starboard in pure reflex.[...]
"What? Can't dump fuel." Anakin checked the gauges. "It's not like it weighs enough to make a difference,and we've got to get to Tatooine."
"Water," she said. "Ballast."
"I didn't check the cargo bay."
"I'll do it," she said, and before he could stop her, she'd strapped Rotta in the copilot's seat and was making her way aft. "I jettison whatever I find, right?"
"Yeah. When you open the cargo hatch, I'll get a red warning light up here, and I'll just bring up the nose and let everything slide out. Don't waste time dragging any crates up to the tail ramp."[...]
The cockpit intercom buzzed. "Master, I'm in the cargo bay now."
"Good. What do you see?"
"Plenty of crates, and the reserve water tanks are showing full. That's five tons at least."
"That might do it. Open the drains on the tanks and make sure you're standing behind anything heavy that's going to slide out the back when you hit the big red button." [...]
"The console warning light flashed to life: CARGO HATCH OPEN. Anakin brought up the nose and the Twilight climbed steeply.
He thought he heard Ahsoka say something, but it was drowned out by the noise of air buffeting the bay. The freighter soared. Suddenly there were no vultures ahead of him, and he was heading into darker skies as the ship climbed.

There's a lot of interesting information here.

1. Five tons, plus some unremarkable and presumably-draggable crates, are sufficient to significantly alter the performance of the Twilight and allow it to escape vulture droids, climbing to orbit over the course of the next page or so until it could make the jump to hyperspace after clearing the atmosphere.

The Twilight's volume is about 4,600 cubic meters, and per our recent ruminations on the density of the engine section of Star Wars vessels, we presumably have good confirmation that her mass might be somewhere in the range of 2300 to 4600 tonnes. And yet, five stated tonnes plus some unremarkable crates is sufficient to offload enough mass to make the ship, whose performance had been less than starfighter-ish previously, to soar and leave starfighters in its dust.

Perhaps our estimates of the mass are thus too high for this ship.

After all, consider that the performance went from slow to starfighters-suck. The jettisoned mass would thus have to constitute a very significant portion of the ship's entire mass. If a total of 100 tons were jettisoned in this circumstance, for instance, I would expect the total ship's mass be no more than 1000 tons . . . probably less.

(And you know, it makes some sense that an empty freighter would be a speed machine, though it's still odd a starfighter would lose to it. Unlike modern vehicles where you have to gear for certain performance preferences (towing requiring a completely different setup than high speed), a spaceship would not really have these concerns assuming the same basic thrust-generating technology was in use for a starfighter versus a freighter. Thus, a freighter would be designed with supreme engines simply in order to move the loaded bulk, but unloaded she'd be a high power-to-weight speed machine.)

2. Anakin notes that the fuel doesn't weigh enough to make a difference. But, he thinks five tons of water and some crates will.

Understand, even if the ship was carrying a full load of crates full of solid lead, it's irrelevant because Anakin's mental calculation was in regards to crates that Ahsoka could drag. Thus the mass and density of the crates in his mind would've been on par with the crates we see two clones always teaming up to carry around on Republic cruisers.

It thus seems unlikely that he would've been expecting even, say, another five tons of cargo. Thus, the total amount he expected to offload ought not have been more than ten tons or so.

Around ten tons of cargo thus outweighed the fuel on the Twilight, significantly enough to be in the "might do it" category versus the "won't make a difference" category.

2A. Also note that he references the need to get to Tatooine in reference to fuel jettison. And we know Teth and Tatooine aren't too far from one another insofar as the duration of the trip.

a. Let's say the ship had a full load of fuel. How much would be needed to reach Tatooine? If it's 1% of the ship's fuel, then 99% of the fuel weighs a lot less than ten tons. If it's 50% of the fuel, then 50% weighs a lot less than ten tons. If it's 75% of the fuel, then 25% weighs a lot less than ten tons. And so on.

b. It's also possible that he checked the gauges and saw that the ship barely had enough to get to Tatooine. In that case, it required much less than five or ten tons of fuel to get there. At rough maximum, then, given that set of parameters and that it didn't weigh enough to make a difference, the ship was going through a very small weight of fuel in order to make orbit and make the jump to hyperdrive to get to Tatooine, not to mention deorbit and landing.

-----------------------------------------

Suffice it to say, it looks like our vessel mass is too high in the case of the Twilight from this example, and moreover we now have confirmation that Star Wars fuel is not very dense in the canon . . . not that we didn't already know that from RotS and the watery fuel scenes (deleted in the film but still present in the script, for instance). However, it's nice to have another confirmation.

Contrast this with Star Wars inflationists who insist that Star Wars fuel is hyperdense magic material . . . and of course contrast the five tons making a performance difference with their claims of Star Wars vessels having densities many times that of water. Such 'fanatics' (to borrow a phrase) can point to whatever they like . . . the canon is what it is, even if they don't understand how it works from their certain point of view.

Interesting find there, Robert. Especially in that scene the Twilight is not doing anywhere near the uber 3,000 g accelerations that the inflationists have been insisting Star Wars ships have, even after Anakin and Asoka dump the 5 tons of water and cargo overboard.

On top of that, the Twilight was able to leave the Vulture fighters way behind, and those starfighters are a fair match for almost any other fighter craft seen in the PT movies in terms of performance.
-Mike

The sci-fi universe the inflationists have created is nifty and might even be entertaining to watch, but calling it Star Wars is just unoriginal.

2046 wrote:Oh, very much so. I recall Wong dismissing nanotechnology on the grounds that carbon fiber is just carbon and won't get magical properties, or somesuch silly claim, but the fact is that the inflationism on density was silly even just on scientific grounds. It isn't necessary to always have the biggest number. I would rather have light materials that can actually be worked with and don't require a crane to pull up a deckplate.

I think I once said something to that effect concerning Babylon 5 some years ago...

As I just posted to ASVS:

To summarize, "Water War"[TCW4] points toward vessel engine densities in the 500-1000 kg/m^3 range, and the newly-canon TCW novelization points to vessel and fuel densities that are far less still in the case of the Twilight. Even if we presume the Twilight's design was not known by Traviss owing to the greater lead time required for novelization-work versus production-work (and thus that the specifics as applied to the Twilight might not be valid), there is still the point that the fuel itself is not especially weighty.

Put simply, then, I see no obvious way to maintain the claim of super-dense ships. The X-Wing suddenly sinking in muck on Dagobah certainly doesn't point to super-dense fightercraft. The X-Wing sinks all of the sudden . . . it sat on the ground beneath the not-terribly-deep water from the time of unsoft-landing until the middle of the stone-stacking exercise. Then R2 freaks because all of the sudden the thing is almost submerged.

Presumably the ground beneath both it and the water gave way somehow, since not only did it sink all of the sudden but also turn by about 30 degrees, as well, given the apparent orientation of the guns versus the ship's prior orientation (with the big tree nearby as a guide). Perhaps the thing that tried to eat R2 had an underwater lair that collapsed? Who knows.

But in any case, I'd say that's more a test of the ground pressure of the lake bottom.

So do we have any canon evidence of massive ships that I'm missing?

There's the crash of the Trade Federation core ship in AotC . . . assuming a 700m sphere that vessel's volume is 179,600,000 cubic meters, suggesting a probable mass of 90 million tonnes or less. I haven't worked the scene to get crash speed and whatnot, but I don't get the sense that it was hypervelocity. At 200 meters per second, for instance, the kinetic energy would work out to less than half a megaton, which doesn't seem too off from the scene as I remember it (and bearing in mind that not all of an impact like that would be in the form of air blast, owing to the comparatively low impact velocity, the fact that it was a strike on the deformable ground by a deformable ship, et cetera).

What else is left?

The X-Wing sinks with a pretty low velocity. The best you can say for it is that it's slightly denser than the water.

I would say that the calculations you're getting off TCW are spotty. There are a couple issues. The first is that we're not actually just talking about crates that can be manhandled out. The plan from the start is to dump everything out the back by tipping the ship and letting it all fall out. That could very easily add up to a significant sum on top of 5 tons of water.

The "official" cargo figure is 70 tons... which is still very much not much compared to the volume you're talking about.

However, I'm very skeptical of your volume for the Twilight. Official dimensions say "Length 34.1 meters, Width 16.97 meters, Height/depth 15.73 meters (outrigger extended."

#1: This ship is actually wider than it is long. This is visible in the model you're using for it, and in other people's models. "Length" probably refers to wingspan here - the longest dimension.

#2: None of the images I've seen for it have the requisite 2:1 wingspan:length ratio. I could believe that originally, they were going to give it a wing on each side, and then clipped it off, and forgot to change the figures.

#3: At that scale, the window becomes on the order of 1.5 meters tall. The problem is that when we see it face-on, that window just shows heads. Note how tall that window strip is compared to the little windows on the Falcon?

Overally, from the exterior shots, it looks like the main body is intended to have a cargo hold that can fit one modern standard shipping container inside & takes up much of the interior of the craft.

If we assume that the key dimension is nose-to-tail, and that's actually the official "width" of ~17 meters (with official "length" referring to the longest dimension, perhaps in slight error), that would be an error factor of eight, roughly an order of magnitude.

If the official length was simply a typo that slipped through, and 17 meters is supposed to be the wingspan (which would be a closer fit for the heads in the windows, but more trouble for Anakin fitting his fighter inside the cargo hold with room to spare), then we're talking about easily another half order of magnitude or so.

Just a quick note at the moment, but you may be right regarding the official dimensions of the Twilight not working properly. I will do some scaling checks following images like:



Based on a 1.5 meter Ahsoka the box height is around ten meters. And though I don't have a good side view handy…



… we can easily get a box three times longer than its height that way.

I also seem to recall the bridge/cockpit windows being fairly expansive, but I will check further.

I would have no issue at all with a smaller Twilight if it fits.

Sorry, senile . . . just remembered I'd left you hanging. My apologies.

I have obtained a superior model of the Twilight than the one shown in the pics, but it's rather labor-intensive to clean out models and I haven't gotten a chance to check the volume yet. (You can see the model in the acceleration demo videos.)

Jedi Master Spock wrote:I would say that the calculations you're getting off TCW are spotty. There are a couple issues. The first is that we're not actually just talking about crates that can be manhandled out. The plan from the start is to dump everything out the back by tipping the ship and letting it all fall out. That could very easily add up to a significant sum on top of 5 tons of water.

The plan is to let everything fall out, yes. However, Anakin basically tells Ahsoka not to worry about moving the crates into position at the door. The fact that he thought she could have done so is relevant.

Let's turn this to a more real-world example. Suppose we're deep in the sticks of Miss'ippi (or Alerbammer) and I've got me a jacked up Silverado with Confederate flags flying off of it and I done put me a big ole engine up in there.

1. I have a number of empty beer cans in the truck bed and the idea is to drop the tailgate and punch the gas so everything falls out of the rear. I tell you "don't waste time dragging any cans up to the tailgate."

That makes sense. You could "drag" them with a broom.

2. I have a number of 30lb bags of concrete mix in the truck bed and the idea is to drop the tailgate and punch the gas so everything falls out of the rear. I tell you "don't waste time dragging any bags up to the tailgate."

That makes sense. You would probably actually drag them in such a case.

3. I have a number of 1 foot cubes of solid lead (weighing in at 700lbs each) in the truck bed and the idea is to drop the tailgate and punch the gas so everything falls out of the rear. I tell you "don't waste time dragging any cubes up to the tailgate."

That doesn't make sense, over and above the fact that we have to pretend my truck could accelerate fast enough to pull it off. You'd have a helluva time dragging, pushing, or otherwise maneuvering them.

Now of course, the reality really ought to be a mixture of crate weights, and perhaps there were some that were basically solid lead. However, there's no direct indication of that. It is clear that Anakin was assuming the crates would be of a draggable weight, much like we always see two clones moving crates around on Venators.

The "official" cargo figure is 70 tons... which is still very much not much compared to the volume you're talking about.

Indeed it isn't. A pity I don't cherry-pick official figures, because that would make a clear top end for this event.