NationStates Jolt Archive

- removed to completely re-work design -

http://i26.photobucket.com/albums/c140/berrik/Smileys/emot-pwnonk.gif

Running off the figures based on your empty weight of 17 kton:

It's 2x1 km and weighs 17 ktons. Let's assume it's 100m high to keep the figure down [because it's most certainly taller, but there's empty spaces in there] = 262,938,300 cubic metres. So 15,466 cubic metres of wankium weighs a ton... =0.064 kg / cubic metre, if my math is right. Air is 1.2. This plane doesn't need engines [or even wings], because the airframe is less dense than air.

You need to be several hundred times heavier before your plane can even be made of material that's solid, your mass is way too low. To put it into perspective, a Kirov class Cruiser is 24,300 tons. It's 251 x 28.5 metres, meaning your plane is 368 times the area but weighs 7,000 tons *less*.

Firstly, “more wing = more lift.”

Um, not so. Large aerofoil shapes actually lose lift after a point, it's a bell curve, not a straight line.

And secondly, “anything will fly with enough thrust.”

Nope, after a point your wings will fly but the rest of you won't. Stress gets too great for the thing to hold together and the wings buckle under their own weight.

OOC: GMC, I've asked nicely in the past for you to keep your incessant criticisms of my stuff to yourself. And you've done just that with my two prior designs that came out since the Partisan. Please don't ruin that great track record, allright?

OOC: GMC, I've asked nicely in the past for you to keep your incessant criticisms of my stuff to yourself.

Maybe you shouldn't design aircraft that would have to be made of gas to reach the mass figure you attribute them, hm? Criticism of designs is legal in this forum, and your weight is impossibly low. Also, you are not a moderator, do not order other posters around.

OOC: The last time, this started out innocently enough, and devolved into a godawful flame war. I do not want that to happen again. Flamewars benefit nobody.

Again, I'm asking real friendly-like, if you don't like the design, that's fine. Just -please- don't start kindling the fire. I'd really appreciate it.

Maybe you shouldn't design aircraft that would have to be made of gas to reach the mass figure you attribute them, hm? Criticism of designs is legal in this forum, and your weight is impossibly low. Also, you are not a moderator, do not order other posters around.

Looked more like a request to me...

Anyways, just using the basic height/length/weight calcs to form a brick which is then used as the base for your calculations is a bit of a red herring, imho.

GMC pointed out a major flaw of the design - it's almost a hundred times less dense than air (Makes a zeppelin look outright solid in comparison. Oh, and the same is true for simple hot-air balloons), meaning that whatever it tries to carry will fall right through the cardboard hull, whose structural strength ought to approach zero.

Now, what an engineer would do, is this: He/ she'd point out that GMCs arguments are flawed due to <enter reason here> and give examples/ do the appropriate math to prove his or her point.

You, erm... failed to do this, instead resorting to whining that is, well... exactly what a designer that'd actually think about what he/ she is designing wouldn't do, as the thinking would involve knowing how to refute criticisms.

And by 'refute' I mean proving that the criticisms are incorrect, not asking to stop it because it may inform potential customers about a design's weaknesses, despite having done next to no work on it, inventing numbers rather than thinking about them.

Again, I'm asking real friendly-like, if you don't like the design, that's fine. Just -please- don't start kindling the fire. I'd really appreciate it.

I'm not saying I really don't like the design; I'm saying there is no physical way it could exist with these figures and still be a solid object. I've given you the numbers to look at; I'd be willing to accept some good-natured wank that you could somehow make this thing without its wings collapsing when it was half-finished and such [and even that it could fly at all], but you're just not going to sell this or get anyone to believe it unless you jack up the mass figure to around a million tons at the very least.

This isn't the same as saying mecha bad, grr mecha; this is me saying you're 368 times the area of a Kirov while being 7,000 tons lighter, and that you just can't make materials do that.

And here we go, spiraling off into the terminology and jargon of classifying weight and density...So what you're saying is that you absolutely refuse to do what every engineer learns to do in his/ her first semester (Assuming that they haven't had it in highschool, which they usually do)?

I'm very sorry, but how can you design stuff without at least emulating the most basic of engineering concepts?

~ Claudia Falkenhayen, Ministry for General Curiosity, DA

I believe, Mr. GMC, you should revisit your math. You calculated the volume of a cube of 1km by 2km by 100m. So, unless the ship is a giant cube (which I doubt because such a thing would be stupid), your calculations are completely wrong. In fact, I highly doubt that you could asertain the exact volume of the ship unless you were an engineer. The ship, any ship, is not a perfect figure, and its shape is based on complex mathematical functions, something that it appears you know nothing about.

I believe, Mr. GMC, you should revisit your math. You calculated the volume of a cube of 1km by 2km by 100m. So, unless the ship is a giant cube (which I doubt because such a thing would be stupid), your calculations are completely wrong. In fact, I highly doubt that you could asertain the exact volume of the ship unless you were an engineer. The ship, any ship, is not a perfect figure, and its shape is based on complex mathematical functions, something that it appears you know nothing about.

Nice trolling there. You're wrong, however. You should note for a start that I stated that the 100m was a very low figure for the third dimension given the shape shown in the picture. You should probably learn about the concept of 'approximation,' since that's what the figure is.

So, let's assume the thing only fills half the volume of the shape, shall we? Still density of 0.128. Still ten times lighter than air. Unless the aircraft only fills one nineteeth of the volume of its total dimensions [meaning 94.7% of the aircraft's dimensions is completely empty space], it's less dense than air. If it does only occupy 5.3% of its entire dimensions, it still couldn't be made of anything that was solid because its density is still too low. To put this into perspective, 17,000 tons of water would occupy a volume of 17,000 cubic metres; this means the actual aircraft's body could only occupy 1/15,467 or 0.006% of its total volume, if it was made of material no more dense than water.

We can compare this to a real aircraft using the same method; the AN-225 is 88.4 x 84 x 18.1 metres with an empty weight of 175 tons. Running off the numbers, this gives us 134403.36 cubic metres, for a density of 0.0013 tons per cubic metre which is 1.3 kilograms per cubic metre, twenty times the density of this aircraft, and that's using the very heavy-handed assumption that the Ouroboros has a wingspan / depth ratio of 21.57:1, which the picture did not.

This means that even if an AN-225 is a solid block occupying its entire dimensions it is more dense than air. If we run our water figures for this, we find if the AN225's empty weight was a solid block of water it would occupy 175 cubic metres, which is 1/768 or 0.13% of the total volume.

Perhaps more notably, the Wright Brothers' Flyer was 6.43 x 12.29 x 2.74m, for a volume of 216.5 cubic metres with a weight of .274 tons. This comes out as 0.001265 tons per cubic metre, which is 1.265 kilograms per cubic metre. Meaning the Ouroboros is also almost twenty times less dense than an aircraft made of balsa wood, wire and canvas with no enclosed areas whatsoever.

We do not need to ascertain the exact volume of the aircraft using 'complex mathematical functions' to make a rough comparison to another aircraft using the same method, or to realise that the rough figure implies Something Is Very Badly Wrong. The exact figure is not the only useful one.

Ok, now let's try to get us a useful guideline figure for mass [since I was in a hurry yesterday, or I'd have done it then]. We'll do this by imagining the mass of the airframe of the AN-225 to be a solid block of aluminium, working out what percentage of the total volume such a block would occupy, and then scaling it up to the volume figure for the Ouroboros.

Ok, density of aluminium is 2.7 tons per cubic metre, so the 175-ton AN-225's airframe would occupy 64.814 cubic metres as a solid block. The volume of the dimensions is 134,403.36 cubic metres, so the airframe here occupies 0.048% of the total volume.

Let's check this aginst a few other similar aircraft to see if it works:

C-5 Galaxy: 75.3 x 67.89 x 19.84m [volume 101,424.4 cubic metres], empty weight 153.285 tons. Using the percentage from the AN-225, we get a solid block of 48.91 cubic metres of aluminium for the airframe, for an empty weight estimate of 132 tons.

AN-124: 68.96 x 73.3 x 20.78m [volume 105,038.08 cubic metres], empty weight 175 tons. We get 50.653 cubic metres which is 137 tons.

Flyer: 6.43 x 12.29 x 2.74m [volume 216.5 cubic metres], empty weight .274 tons. We get 0.104 cubic metres of aluminium which is 0.282 tons.

So, while this method isn't staggeringly accurate [and if you try it on things that aren't large cargo planes you get ridiculously low figures because we're basing it on a plane full of large empty spaces], we can generate a figure somewhere close to the real one with it. Now, we know that assuming the Ouroboros is only 100m high, it has a volume of 262,938,300 cubic metres. Therefore we get a block of aluminium with a volume of 126,796.736 cubic metres, weighing us in at an empty weight of 342,351.2 tons. And this is likely to be a low figure, remember.

Will you give it a rest already? I've pulled the design until I can come up with some more appropriate figures. I'm presently doing work with some Draftroom people to get an actual volume measure and stat it accordingly.

In fact, you're a moderator, can you delete this thread entirely? For the purposes of II RP, this design never existed, because it was impossible. -_-

Stupid mathematics....

Will you give it a rest already? I've pulled the design until I can come up with some more appropriate figures.

Um, I'm trying to help you by giving you an estimate of what to aim for. Can lock it, if you'd prefer, but not delete it.