StarDestroyer.Net BBS

Surlethe wrote:That's an excellent question. I guess I'd just assumed they stayed in the air all the time, since they're shitting all over the laws of physics anyway. Of course, if they do that, then I don't really have a problem with the shape of the hull as long as they're consistent.

Not all magi-tech means of negating gravity are created equal. Unlike skystone or repulsorlifts, some schemes require energy constantly pumped into them to even idle. For heavier-than-air airships that operate unders such schemes, it obviously makes sense to set them down when you can.

Sea Skimmer wrote:Also I have noticed that later parts of the comics have T-34s and TV sets rolling around.... does this comic jump around in time or what?

It looks like there's a "modern era" and "WW1 era" to them, with many of the same characters. Hopefully more will be revealed as time goes on.

The Duchess of Zeon wrote:Also, how would one calculate the range of the main guns, say, firing at an elevation of 45 - 50 degrees, from a ship-altitude of 10,000 feet?

You could have a very basic back-of-the-envelope estimate ignoring pesky details such as aerodynamics by using the usual trajectory calculations.

I doubt there's jumping around in time.

Rather than time travelling, the evidence would suggest inter-dimensional travel. With the modern setting potentially being our world.

Adrian Laguna wrote:I doubt there's jumping around in time.

Rather than time travelling, the evidence would suggest inter-dimensional travel. With the modern setting potentially being our world.

Sounds about right, actually.

phongn wrote:

Adrian Laguna wrote:I doubt there's jumping around in time.

Rather than time travelling, the evidence would suggest inter-dimensional travel. With the modern setting potentially being our world.

Sounds about right, actually.

I think it's done kinda explicitly in a fairly recent one, where you have a group show up on the top of a building.

I've read the whole thing and it does get a tad confusing. Those airships I think actually land on ground. I know the troop transport airship and the freighter airship can land on the ground despite looking like they were made for water.

Tech wise looks messy. Military wise it looks like a high tech WW1-2 style weaponry and so forth while the rest seems like modern day tech. The only thing I see as "future" tech is the gatestone.

Enigma wrote:I've read the whole thing and it does get a tad confusing. Those airships I think actually land on ground. I know the troop transport airship and the freighter airship can land on the ground despite looking like they were made for water.

Those need to land on ground, so they've been engineered too. The difficult of making a 30,000-ton battleship land on ground, however, is probably too great (remember that the average cargo ship of the 1910s was 3,000 - 4,000 tons).

Also, if you read to Page 150 or so it becomes very clear that they're infiltrating modern day earth by some sort of magi-tech gate mechanism, presumably to gain our resources and technology to aid both in the internal power struggles of the Empires and in the War.

The Duchess of Zeon wrote:Also, if you read to Page 150 or so it becomes very clear that they're infiltrating modern day earth by some sort of magi-tech gate mechanism, presumably to gain our resources and technology to aid both in the internal power struggles of the Empires and in the War.

Page 150 just brings up the conversation between Nicole and her sister Laura. Are you talking about the two big cats? The way I see it, the webcomic artist went bonkers and decided to give the armed forces a retro feel. The first chapter shows Laura as the ruler of her nation in a WW1 style war, while the rest of the webcomic shows her as just an athletic uni student in a modern setting. I don't know it is just confusing to me.

Enigma wrote: Page 150 just brings up the conversation between Nicole and her sister Laura. Are you talking about the two big cats? The way I see it, the webcomic artist went bonkers and decided to give the armed forces a retro feel. The first chapter shows Laura as the ruler of her nation in a WW1 style war, while the rest of the webcomic shows her as just an athletic uni student in a modern setting. I don't know it is just confusing to me.

I'm talking about the big cats, yes.

The context is clear--they're preparing for a second round, which is more WW2 in style.

The WW1 war is backstory, like a lot of WW1 scenes are for WW2-era settings.

There's an implication, also, that lots of nobles have been exiled into the modern Earth in internal political struggles.

I would say that happened to Laura because of her success (which made the more powerful Imperial dynasty concerned about her) and she's biding her time here in hope of a change in the situation back home.

Darth Raptor wrote:

Surlethe wrote:That's an excellent question. I guess I'd just assumed they stayed in the air all the time, since they're shitting all over the laws of physics anyway. Of course, if they do that, then I don't really have a problem with the shape of the hull as long as they're consistent.

Not all magi-tech means of negating gravity are created equal. Unlike skystone or repulsorlifts, some schemes require energy constantly pumped into them to even idle. For heavier-than-air airships that operate unders such schemes, it obviously makes sense to set them down when you can.

Does it? Leaving aside the sheer inefficiency of an antigrav tech that requires loads of energy constantly being pumped in to hover, keep in mind that it takes even more energy to get back off the ground up to where you were. So if you've got a 10,000 ton = 1e7 kg battleship at 10,000 ft = 3048 m, and if you have to expend, say 1 mW per kg to keep it in the air at any given height, then if you want to take it down and then bring it back up in any reasonable timeframe (3 km in maybe two hours, to stretch it), you'll have to expend 4e7 W, three orders of magnitude more than simply idling in midair. The only way you can make it break even is if you spend more than 345 days on the ground. It seems grossly more efficient to simply refuel in midair: you're only dealing with the cost of bringing the fuel up, which you'd have to do with landing the battleship anyway, and you don't have to deal with all the armor, ammunition, and other fun things battleships have that fuel transports don't.

I guess I'm having trouble a priori suspending technical disbelief about the consistency of having the ability to exert forces on the order of 4e8 N (a WWII battleship weighed about 40,000 tons), generate power on the order of 1e8 W = 10 MW, and be in a WWII-esque setting.

The Duchess of Zeon wrote:The context is clear--they're preparing for a second round, which is more WW2 in style.

The WW1 war is backstory, like a lot of WW1 scenes are for WW2-era settings.

Slight problem, the WW1 scenes (you mean the first chapter, right?) have yet to happen.

Surlethe wrote:I guess I'm having trouble a priori suspending technical disbelief about the consistency of having the ability to exert forces on the order of 4e8 N (a WWII battleship weighed about 40,000 tons), generate power on the order of 1e8 W = 10 MW, and be in a WWII-esque setting.

I'd find it rather likely that they do not generate such power and they fly using magical fields or whatever.

Adrian Laguna wrote:

Surlethe wrote:I guess I'm having trouble a priori suspending technical disbelief about the consistency of having the ability to exert forces on the order of 4e8 N (a WWII battleship weighed about 40,000 tons), generate power on the order of 1e8 W = 10 MW, and be in a WWII-esque setting.

I'd find it rather likely that they do not generate such power and they fly using magical fields or whatever.

Glancing through the first several pages of the comic, they don't seem to apply the magitech anywhere else. That sort of power generation technology should be obvious anywhere; hell, even if it's people capable of causing fields that can put out in excess of 10 million watts, you'd think they'd be the center of the military. Also, if they can arbitrarily generate 4e8 N (without seeming to violate Newton's 3rd law! So that's what's been bugging me about this), why haven't they applied it to actual weapons technology? Those are the sorts of things I'm talking about when I say it breaks my suspension of disbelief.

EDIT: According to Wikipedia, Saturn-V rockets generated 34 million N of thrust in their first stage. That's an order of magnitude less than what we're talking about here. These people should be on the moon; are they?

DOUBLE EDIT: A NASA publication (.pdf) confirms the 3.4 MN figure: 7.5e6 lbf = 3.3e7 N.

What I mean by "magical fields" is that you turn the shit on for a low power requirement and something else entirely provides the force needed to lift it up. You may note that the only thing a submarine needs to do in order to gain altitude is fill its ballast tanks with air. It might be something kinda like that, but with weird magics.

Adrian Laguna wrote:What I mean by "magical fields" is that you turn the shit on for a low power requirement and something else entirely provides the force needed to lift it up. You may note that the only thing a submarine needs to do in order to gain altitude is fill its ballast tanks with air. It might be something kinda like that, but with weird magics.

The point I'm making is so long as they're not making use of technology known to us (and they're not, or else we'd have flying battleships), the sort of technology or magic or whatever you want to call it capable of the non-trivial feat of lifting 40,000 tons of steel thousands of feet into the air should have far-reaching industrial uses.

Addendum: The buoyant force on a battleship from the surrounding air will be about 9e5 N. To do a submarine trick, you'd have to decrease the density of the ship -- and hence the density of steel -- by a factor of about 400. Remember, there's air on the inside so the crew can breathe, so it's not like a ship, which can't have any water inside it.

It's just an analogy, I'm quite aware buoyant force doesn't apply.

Surlethe wrote: I guess I'm having trouble a priori suspending technical disbelief about the consistency of having the ability to exert forces on the order of 4e8 N (a WWII battleship weighed about 40,000 tons), generate power on the order of 1e8 W = 10 MW, and be in a WWII-esque setting.

10 megawatts you say?

A typical Japanese heavy cruiser displaced 14,500 tons and had 150,000shp from four turbines and twelve boilers. That’s 111 megawatts for propulsion and the ship is actually making a bit more power then that to run its existing auxiliary equipment and multiple large moving weapons and directors. A similar plant, powered the 72,000 ton Yamato and Japanese several aircraft carriers in the range of about 30,000 tons. The US 1939 South Dakota had 130,000shp, 97 megawatts. Iowa has 212,000shp and somthing like 7,600 tons fuel oil capacity.

WW1 battleships are lower powered, the 1920 South Dakota had 50,000shp and a very advanced turbo-electric drive system. HMS Revenge had 40,000shp, however the WW1 battlecruisers went as high as 151,000shp for 1916 HMS Hood. For an earlier smaller battlecruiser example HMS Princess Royal made 70,000shp for about 52 megawatts.

Even a 2,000 ton 1930s destroyer could have 50,000shp from two turbines and two or four boilers. 10MW is no problem.

So we're back to simply the mechanism being unknown.

The lift engine could just have a Star Trek bullshit based effect which neutralizes the downward effects of gravity on the ships mass. Its use might be limited by other factors, like being built of 50 tons of Swiss watch parts reassembled into a Nazi German created ‘perfect aryan’ design.

One reason why you may not see the technology used elsewhere is that they don't actually HAVE the technology (i.e., they don't understand how it works). Maybe they're exploiting "natural" resources (think skystone) that grant them those abilities. Just looking at how primitive everything else looks, I wouldn't be surprised if that's the case. It could be exotic, complex matter of alien origin or artifacts left over by an ancient, hyper-advanced civilization.

One method of having large flying ships in an alternate universe without regular engines or wings for lift is technically interesting, although it is fairly impractical.

Earth's magnetic field of around 0.5 to 0.6 gauss (~ 0.00005 tesla) at the poles is borderline at best for having even a lightweight magnetic lift craft with real-world superconductor performance, let alone a more dense, massive flying ship. But technically one could imagine an alternate civilization making gigantic underground superconductor loops, in circles many kilometers in diameter, to create a much greater magnetic field over many square kilometers of their planet, such as with sufficient strength up to thousands of meters altitude. By much greater, one doesn't mean multi-tesla magnetic field strength, rather a very small fraction of a tesla, though perhaps two or three orders of magnitude greater than 0.00005 tesla.

Such would still be too weak to have noticeable repulsive effect on diamagnetic objects like water, human bodies, etc. It would have significant attractive effect on ferromagnetic objects. But magnetic flight ships could be made with superconducting magnets onboard oriented in opposition to the "ambient" magnetic field from the giant underground superconducting magnets. Smaller control surfaces and conventional propeller or jet engines provide stabilization and horizontal thrust.

For such magnetic lift, the nominal power usage is zero for a ship to remain stationary at a given altitude, with superconducting magnets having lossless circulation of current indefinitely ... but in practice that isn't the case. There is electricity consumption for stabilization, for keeping the superconductors cold (sufficiently lightweight refrigeration equipment being of uncertain plausibility with today's tech even with good thermal insulation), and so on. Whenever a superconducting electromagnet is delivering kinetic or potential energy to an object, such as the ship levitating itself higher in altitude, a corresponding amount of power input is required.

Is it competitive compared to a regular aircraft in infrastructure cost and requirements? Of course not. It is very, very impractical by most standards. The ships have to be designed around compatibility with their "repulsor" superconducting electromagnets, such as resulting precautions against ferromagnetic objects onboard. It requires vast industrial capability and expenditures to even set up the system. It tends to be particularly impractical and implausible for flying battleships in war since any enemy damaging the ground superconducting infrastructure causes the ships to fall down. And the installations don't tend to exist in enemy territory.

It is particularly difficult on a planet compared to lower-gravity bodies.

But the preceding is a fun exploration of what is technically possible within the laws of physics, however impractical. It would look cool.

This isn't meant as directly applicable to what is described in this thread, particularly not for a WWII-tech-level setting.

Darth Raptor wrote:It could be exotic, complex matter of alien origin or artifacts left over by an ancient, hyper-advanced civilization.

Actually, that would almost work with the magnetic lift idea. An advanced enough alien civilization could basically change a planet's magnetic field with artificial equipment more deep underground than a less advanced civilization could reach. Still, on the other hand, the relatively strong magnetic field is only in the proper orientation over part of the planet's surface, not all (a little like earth's magnetic field can exert vertical force at the poles but isn't vertical field lines at the equator). And even with a good ambient magnetic field, there are other issues, like alien artifacts being needed for the onboard superconductors as well unless the locals' superconductor tech is well beyond WWI-WWII earth.

Surlethe wrote:without seeming to violate Newton's 3rd law! So that's what's been bugging me about this

Hovering does not violate the 3rd law. Nothing moves, so there is in fact, no action requiring a reaction. If something does in fact need to move, there could be some bullshit field that interacts with the earth, reacting against the earth itself.

Darth Raptor wrote:One reason why you may not see the technology used elsewhere is that they don't actually HAVE the technology (i.e., they don't understand how it works). Maybe they're exploiting "natural" resources (think skystone) that grant them those abilities. Just looking at how primitive everything else looks, I wouldn't be surprised if that's the case. It could be exotic, complex matter of alien origin or artifacts left over by an ancient, hyper-advanced civilization.

You're not thinking back to 1914 enough, DR.

Think about this. Why am I limiting their altitude to 10,000 feet?

Oxygen

They're getting those 10 megawatts of power from steam engines. At altitudes above 10,000 feet, you are not going to be running a steam engine except on forced drought (basically massive blowers create a continuous air suction effect into the boilers), and forced draught isn't going to take you all that much higher.

Then what happens? Nobody can function above a certain altitude because people need air to breath, too. They take those battleships much beyond 20,000 feet and they're all dead onboard--and they can't last at 20,000 feet for more than a few minutes.

Solution? There's only one available with 1914 tech: Oxygen masks. There aren't any pressure suits yet, so we're talking about just masks around the face. Now we can push our altitude up to, maybe, on the order of 40,000 feet. The results will be extreme. The crew will be freezing in their positions. Men will go insane. Mask function must be constantly checked. Read up on what the crews of the German Airships on the so-called "Silent Raids" in 1917 went through for a good idea of how fucking difficult it is to operate an unpressed vehicle with just oxygen masks at that kind of altitude.

So that is why they are not on the moon. They don't have any pressurization systems whatsoever, for starters, and I'm sure you can think of many more problems like that pretty darn quickly.

Also, don't knock massive flying ships in terms of usefulness. It could be all their production capacity goes to those because they're incredibly useful. Shipping is by far the most economical form of transport in the world, ever, and if their flying ships are just as efficient, then we're talking about incredibly cheap trasport everywhere for them, which means huge economies, and vast material prosperity for everyone on the planet, even if their technology level is low. Transportation is by far the most useful application for this kind of technology, and the most lucrative.

Beowulf wrote:

Surlethe wrote:without seeming to violate Newton's 3rd law! So that's what's been bugging me about this

Hovering does not violate the 3rd law.

I said it seems to violate it. It might in fact not violate the law -- e.g., if there were some bullshit mass-lightening effect or something and it were simply being held up by Pascal's principle.

Nothing moves, so there is in fact, no action requiring a reaction. If something does in fact need to move, there could be some bullshit field that interacts with the earth, reacting against the earth itself.

Your characterization of the 3rd law is simply wrong. Just because the net force on a flying ship is zero does not mean that there are no forces acting on the ship.

Sea Skimmer wrote:10 megawatts you say?

A typical Japanese heavy cruiser displaced 14,500 tons and had 150,000shp from four turbines and twelve boilers. That’s 111 megawatts for propulsion and the ship is actually making a bit more power then that to run its existing auxiliary equipment and multiple large moving weapons and directors. A similar plant, powered the 72,000 ton Yamato and Japanese several aircraft carriers in the range of about 30,000 tons. The US 1939 South Dakota had 130,000shp, 97 megawatts. Iowa has 212,000shp and somthing like 7,600 tons fuel oil capacity.

WW1 battleships are lower powered, the 1920 South Dakota had 50,000shp and a very advanced turbo-electric drive system. HMS Revenge had 40,000shp, however the WW1 battlecruisers went as high as 151,000shp for 1916 HMS Hood. For an earlier smaller battlecruiser example HMS Princess Royal made 70,000shp for about 52 megawatts.

Even a 2,000 ton 1930s destroyer could have 50,000shp from two turbines and two or four boilers. 10MW is no problem.

Huh. That's fascinating; thanks for the info. The biggest discrepancy, though, is still the ability to apparently exert ten times as much thrust as a Saturn V rocket. Why aren't they using this tech for launching weapons, e.g.?

That reminds me: how do they compensate for the effect of firing their heavy guns? That should throw them off-course.