Making a large effortpost in the thread for a potential Dragon-slaying weapon. Parts are copy pasted from the Discord.
So I've been thinking about Five Seal Barrier'd (FSB'd) spidersilk as a potential Dragon-slaying weapon for a while now. I call the proposed weapon the skyslicer. I want to deploy it against Dragons when Hazou's Consequences heal.
The basic idea of a skytower is to use a coil of ninja wire to support a wooden platform in the sky at arbitrary altitude. This has possible weaponizable properties, wires will cut if sufficient force is applied to them, the thinner the wire the easier they cut. Skip the platform on a skytower and you're halfway to ruining the day of any flying creature that runs into the support.
It's possible to improve on this in a couple ways, use spidersilk instead of ninja wire, spidersilk is stronger for a thinner cord, IRL spiders can do about 3 μm, thinner than a razor blade. It would take some experimentation to find the optimal thickness of silk for covering as large an area as possible without breaking. FSB's can be applied 3-100 m from the central seal, so we're looking at a possible area covering a disk 200 m in diameter. Rather than using straight lines to go out to the seals, use wiggles and loops to cover as much of the internal area of the disk as possible. Camouflage the outriggers that the support seals lie on so that they blend into the sky better. Other suggestions welcome here!
Thankfully there's no problem with using as much spidersilk as practical to hold in place. The FSB is limited by volume of the object even a very long thread has a tiny volume compared to moderately sized three dimensional objects.
The effect should be like an apple slicer on meth, anything that flies or runs into the disk is chopped to bits by the skyslicer. No earthly creature would even feel resistance at even a moderate running pace.
The steps to deploy the skyslicer look something like this:
1) Get some Arachnids and Hornets trained in the activation of seals (already done?)
2) Set up skyslicer(s) and a waiting ambush
3) With the bait teams we've been using to lure the Dragons away from the GS, lure a the target Dragon into the skyslicer. Try to catch the Dragon mid-lunge. Make sure to get far enough away from the GS that seals/jutsu behave normally
4) If the Dragon somehow survives, attack it with implosion seals, earbusters, explosives, youthanizers, anything we can think of - suggestions welcome here
5) It should be dead, if it's still alive, get the hell away
Now this would work on anything that obeys the laws of physics. Dragons possibly don't, but let's make some reasonable assumptions and see how tough their scales would need to be to resist an attack like this.
This is the current best working description we have of a Dragon. If we take the serpentine description and run with it (as the others don't exactly have real life equivalents), we can compare it to real life snakes. The
largest of which is the green anaconda, which can reliably weigh 97.5 kg for a 5.6 m (18 ft) snake.
(This next section is based on my best guesses, criticism welcome and numbers will be updated)
Now we scale up according to the square-cube law, where every doubling of length multiplies the volume -and therefore the mass- of the serpentine creature by eightfold. 18 -> 36 (x8) -> 72 (x64) -> 144 (x512) -> 288 (x4096)
So a small dragon (80 ft) should weigh about 7,000 kg, a medium (150 ft) at 50,000 kg and a large (300 ft) at 400,000 kg. For reference, the heaviest blue whale ever recorded clocked in at 190000 kg. So we're not getting totally crazy here. Animals that heavy shouldn't be able to breathe out of the water, let alone fly, but chakra is a thing in MfD. Our wild asspulling is looking pretty good so far.
All we have to go based on speed is "frighteningly fast in sustained flight" and "terrifyingly fast in a quick lunge". As enormous multi-ton serpents(?), there's no possible physical way they could ever keep up with a 4 oz bird. So I'll be generous and say they do
peregrine falcon diving speed (fastest animal flight) as their quick lunge flight speed, that's about 100 m/s (250 mph). Since peregrine falcons typically cruise about 1/5 of their diving speed, I'll do an appropriate decrease for cruise speed, call it 20 m/s (50 mph). I would call those numbers frighteningly fast and terrifyingly fast. I sure would be frightened if I saw a 150 ft Dragon coming at me at 50 mph.
This formula is great, thanks for already doing all the actual work, my only quibble is that I'm unsure where the 60 μm figure for the diameter of the spidersilk came from, I seem to be getting 3 μm when I Google. I'm going to run with my number, but I'll keep the disagreement in mind. Otherwise this is perfect for the next step. Which is to see how a single line of a skyslicer impacts a small, medium and large size Dragon at cruising and lunging speeds. I'll keep d = 5 cm. That seems like a generous amount of elasticity for anything. The harder the scales, the less they'll deflect anyway. For the cross sectional area, I will use the longest axis that the Dragon could possibly impact on-the side.
Small Dragon, cruising- ((0.5*7000*20^2)/0.05)/(21.336*3e-6) = 437 GPa
Small Dragon, lunging- ((0.5*7000*100^2)/0.05)/(21.336*3e-6) = 10900 GPa
Medium Dragon, cruising- ((0.5*50000*20^2)/0.05)/(45.72*3e-6) = 1450 GPa
Medium Dragon, lunging- ((0.5*50000*100^2)/0.05)/(45.72*3e-6) = 36500 GPa
Large Dragon, cruising- ((0.5*400000*20^2)/0.05)/(91.44*3e-6) = 5830 GPa
Large Dragon, lunging- ((0.5*400000*100^2)/0.05)/(91.44*3e-6) = 146000 GPa
So this very generous model says that at cruising speed, the very smallest Dragons impact with more than 1500x enough pressure to puncture steel. When lunging, the largest impacts with 530,000x the pressure needed to puncture steel. But forget about steel, steel is weak.
Diamond has a Vickers hardness of 115 GPa, still lower than the pressures created in the collision with the smallest Dragon at cruising speed.
This will cut scales made of biodiamond. If they can be hurt by physical objects, this
will hurt them.
Draping more threads over the total cross section of the Dragon will slice them into smaller pieces. I think that's important for making the skyslicer more damaging. It will increase the impact cross section and decrease the pressure. So I have been very generous in the model so far (5 cm deflection, impact over entire length of longest axis) to account for it. Under my assumptions about mass and velocity, a more rigorous model would output higher pressures, I am fairly confident (70%).
If you want to take this further. I'd say 15 cm thickness hardened steel for their scales-that's the thickness of modern tank armor, with mass and velocity as detailed in this post. Also any issues or revisions you have with my mass and velocity estimates are more than welcome.
That's all for why the weapon should work on anything that obeys physics. The last word on Discord was to bring this to Kumokugo (sanity check with Mari, go over tactics with Keiko and Shikamaru, and ask Asuma if we can share OPSEC first ofc) and start field testing skyslicers if she thinks the idea has merit. IMO we need seal trained Hornets to really get the most out of the skyslicer, and the teams shouldn't be emplacing one for the first time during the ambush, that means time to run drills and prepare, as well as get more Hornets and Arachnids trained on seal activation.
EDIT 1: Added comparison to hardness of diamond, very favorable