Pacific Rim- how to do it more efficiently?

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Re: Pacific Rim- how to do it more efficiently?

Post by Sky Captain »

Q99 wrote:Because the big problems with torpedoes and speed aren't simply power. Drag, and translating the power into motive force are the issue. Simply making a propeller that's the same size go faster and faster has diminishing returns.
It depends how close to the limits are current torpedo propulsion. No one has submarines or major surface ships that go faster than 70 - 80 km/h so there never was serious incentive to push conventional torpedo speeds into hundreds of km/h range if existing torpedo performance are good enough.
There are compact waterjet propulsion systems used on high end speedboats that can translate several megawatts of engine power into a motive force so that area also seems to be already solved.
Q99 wrote:Or to put it another way- rather than assuming they can't, the problem is none of the observed technologies show such a method, so you'd have to assume they can.
No need for those, just better battery or some other form of compact energy storage.
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Re: Pacific Rim- how to do it more efficiently?

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Sky Captain wrote: It depends how close to the limits are current torpedo propulsion. No one has submarines or major surface ships that go faster than 70 - 80 km/h so there never was serious incentive to push conventional torpedo speeds into hundreds of km/h range if existing torpedo performance are good enough.
There are compact waterjet propulsion systems used on high end speedboats that can translate several megawatts of engine power into a motive force so that area also seems to be already solved.
There was enough incentive to invent supercavitating torpedoes- the primary limiter for this type of thing tends to be drag, as adding more power has diminishing returns. The faster you go, the less turning a propeller at the same rate adds. That's the main problem- that, and I'm not sure how fast one can physically make one go.
No need for those, just better battery or some other form of compact energy storage.
The fact that the plasma gun charges up does suggest some sort of energy storage system- though I will note, nothing in that implies 'compact.' Just because you can do something big doesn't mean you can scale it down. Also, not just small, but low-mass is something you want. If it's high energy density but also high physical density, then you've just upped how much you need to push by a lot. And the plasma gun capacitor only needed to hold power for a short time (they never went into battle with it charged, which says a lot), while this one needs to operate for a sustained length.

It's assuming undemonstrated capability, in short. Something like that would've been quite helpful to them if it existed.
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Re: Pacific Rim- how to do it more efficiently?

Post by Elheru Aran »

IIRC, most submarines don't go much past ~30ish knots max. There are a few speed tests that do better than that, but they involve some seriously wacky designs like the Albacore's tuna-shaped body, not necessarily practical for a modern submarine or torpedo. Sure, a smaller body like a torpedo has will go a bit faster, but again, diminishing returns. There's a reason the Shkval is shaped like a rocket-- it's basically one. Since a torpedo doesn't have to worry about G-forces or crew or a pressure hull, it can economize on certain aspects of design that a submarine can't, but barring some funky propulsion system being invented in the future, non-supercavitating torpedoes have pretty much hit their ceiling as far as speed goes with current technology, as far as I know (Skimmer or anybody else is welcome to set me right).
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Re: Pacific Rim- how to do it more efficiently?

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The Spearfish is the fastest conventional torpedo I can find at 80 knots, and they were an end-of-cold-war era design, coming into service in the 90s.

Notably, they were designed with catching high-speed 40 knot subs in mind- you want your torpedoes significantly faster than your targets, of course.

And a torpedo would need to go not just a little faster, but a number of times faster to even match speed.
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Re: Pacific Rim- how to do it more efficiently?

Post by Venator »

Rather than pumping work into torpedo speed and accuracy, my thoughts turn to quantity - and optimization.

One thing that always bugged be about Kaiju was that they seem absurdly optimized in their defenses - they shrug off tons of conventional ordinance, survive repeated nuking, and yet blunt-force trauma and the occasional stabbing work wonders. Ignoring writer's fiat and inconsistent science and taking it at face value...

Why not try lamprey-style torpedoes - decent but not outlandish propulsion, thermal guidance and a drill. Find warm thing > drill until it stops being warm. Build by the shipload.
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Re: Pacific Rim- how to do it more efficiently?

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Venator wrote: One thing that always bugged be about Kaiju was that they seem absurdly optimized in their defenses - they shrug off tons of conventional ordinance, survive repeated nuking, and yet blunt-force trauma and the occasional stabbing work wonders. Ignoring writer's fiat and inconsistent science and taking it at face value...
I will note blunt force trauma only ever stuns them from what we see- it's plasma cannons, missile volleys, or blades to vitals that do the killing. Otachi got cuts from Otachi, thrown, punched by Cherno, combo-punched by Striker, boat-batted by Gipsy, and while it took some time to shake off, each of those attacks were shaken off until it got a limb sliced off and it fell from super far.

And there's some variety in defense. Some have exoskeletons, some endoskeletons, but it is all the same material so, yea, there's some aspects of the defense which seem to be set.


Why not try lamprey-style torpedoes - decent but not outlandish propulsion, thermal guidance and a drill. Find warm thing > drill until it stops being warm. Build by the shipload.
Hm, couldn't it use it's limbs to slap itself, much as we do a mosquito? And the bones may chew up drillbits...
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Re: Pacific Rim- how to do it more efficiently?

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Q99 wrote:The Spearfish is the fastest conventional torpedo I can find at 80 knots, and they were an end-of-cold-war era design, coming into service in the 90s.

Notably, they were designed with catching high-speed 40 knot subs in mind- you want your torpedoes significantly faster than your targets, of course.

And a torpedo would need to go not just a little faster, but a number of times faster to even match speed.
You need great speed advantage only if attacking from tail. If torpedoes are deployed in path Kaiju is likely to swim and can attack from front you could get away with slower speeds. As long as Kaiju don't have some kind of sensors to detect approaching torpedo there should be no problem to achieve impact.
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Re: Pacific Rim- how to do it more efficiently?

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To guarantee a hit you would have to launch multiple torps from multiple frontal angles to ensure they don't just turn one way or another to dodge the things. Humans could put multiple remote launcher's around the breach, each armed with multiple torps like the American middle launcher that had many missiles in tubes all together. You couldn't miss it if you saw a picture of one. Except these would be on the bottom strung around the breach. If the nuke depth charge suspended just over the breach didn't work you get the torps going.
Well good thing their "entrance" to the Pacific ocean seems to be fixed.

P.s. as I wrote that I wondered, maybe all this talk of super deep, super sonic torps was barking up the wrong tree. Why does it have to be a torp? Why not a rail gun? Perhaps with some sort of hunting bullet derived bullet design. The problem with making a torpedo work that deep much less up to super sonic speed would be negated because the ammunition would not need any sort of propulsion stage. The M.A.C. gun would do all of that for you, and as has been pointed out many times the enemies launch point is not only ascertained but apparently completely FIXED.
Thought's??
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Re: Pacific Rim- how to do it more efficiently?

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Sky Captain wrote: You need great speed advantage only if attacking from tail. If torpedoes are deployed in path Kaiju is likely to swim and can attack from front you could get away with slower speeds. As long as Kaiju don't have some kind of sensors to detect approaching torpedo there should be no problem to achieve impact.
From the front on, yes. From any other angle, you'll need speed. If you're firing from the side, it'll probably end up a tail chase. A kaiju goes straight up, or at an angle, you're not too likely to get a front shot.


They can turn pretty fast, too, which will throw off a lot of attacks... and they seem like they have some detection range, since they were circling the Jaegers at a distance. If it's supercavitating, that's loud and obvious. Heck, anything going really fast is gonna make some noise no matter the method. Plus after the first, they're always going to be expecting Torpedoes, so they can go on full evasive courses.

JI_Joe84 wrote: P.s. as I wrote that I wondered, maybe all this talk of super deep, super sonic torps was barking up the wrong tree. Why does it have to be a torp? Why not a rail gun? Perhaps with some sort of hunting bullet derived bullet design. The problem with making a torpedo work that deep much less up to super sonic speed would be negated because the ammunition would not need any sort of propulsion stage. The M.A.C. gun would do all of that for you, and as has been pointed out many times the enemies launch point is not only ascertained but apparently completely FIXED.
Thought's??
That... is an interesting idea. Though the projectile will slow constantly through the water, so your range is likely pretty limited, and no adjusting aiming like the torp would have.
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Re: Pacific Rim- how to do it more efficiently?

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Elheru Aran wrote:IIRC, most submarines don't go much past ~30ish knots max. There are a few speed tests that do better than that, but they involve some seriously wacky designs like the Albacore's tuna-shaped body, not necessarily practical for a modern submarine or torpedo. Sure, a smaller body like a torpedo has will go a bit faster, but again, diminishing returns. There's a reason the Shkval is shaped like a rocket-- it's basically one. Since a torpedo doesn't have to worry about G-forces or crew or a pressure hull, it can economize on certain aspects of design that a submarine can't, but barring some funky propulsion system being invented in the future, non-supercavitating torpedoes have pretty much hit their ceiling as far as speed goes with current technology, as far as I know (Skimmer or anybody else is welcome to set me right).
They largely have, something past the present ~80 knots would no doubt be possible but it'd come at the cost of too little range for real uses.

Even normal torpedoes are a good part of the way to being rockets on the energy scale, all the fastest ones are all combustion powered and the fuel is more or less rocket fuel, usually a single monopropellent but sometimes fuel and oxidizer. Spearfish uses ammonia perchlorate as its oxidizer, same stuff used for the space shuttle booster rockets. Its being burned in a turbine or piston engine in the torpedo context to extend endurance.

Many rocket torpedoes existed before Shkval but they typically had ranges of no more then 1,500 yards or less.
See:www.geoffkirby.co.uk/rocket-torpedoes.pdf

Something like an underwater Sprint or giant underwater EM gun should be possible at similar ranges, perhaps even more, if you drive with enough energy you'll supercavitate from the shear force of impact. Its going to be a really violent ride though.

If movie tech comes into play then perhaps you could just generate a high enough pressure to maintain supercavitation at any depth, and size, and have an actually relevant amount of gas pressure time to exploit the speed. And have the rocket to propel it on top of that. This would also imply though that we should have a lot more powerful explosives too though. Our Sidewinders should be leveling buildings kind of upgrade.
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Re: Pacific Rim- how to do it more efficiently?

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Q99 wrote:
Sky Captain wrote: You need great speed advantage only if attacking from tail. If torpedoes are deployed in path Kaiju is likely to swim and can attack from front you could get away with slower speeds. As long as Kaiju don't have some kind of sensors to detect approaching torpedo there should be no problem to achieve impact.
From the front on, yes. From any other angle, you'll need speed. If you're firing from the side, it'll probably end up a tail chase. A kaiju goes straight up, or at an angle, you're not too likely to get a front shot.


They can turn pretty fast, too, which will throw off a lot of attacks... and they seem like they have some detection range, since they were circling the Jaegers at a distance. If it's supercavitating, that's loud and obvious. Heck, anything going really fast is gonna make some noise no matter the method. Plus after the first, they're always going to be expecting Torpedoes, so they can go on full evasive courses.

JI_Joe84 wrote: P.s. as I wrote that I wondered, maybe all this talk of super deep, super sonic torps was barking up the wrong tree. Why does it have to be a torp? Why not a rail gun? Perhaps with some sort of hunting bullet derived bullet design. The problem with making a torpedo work that deep much less up to super sonic speed would be negated because the ammunition would not need any sort of propulsion stage. The M.A.C. gun would do all of that for you, and as has been pointed out many times the enemies launch point is not only ascertained but apparently completely FIXED.
Thought's??
That... is an interesting idea. Though the projectile will slow constantly through the water, so your range is likely pretty limited, and no adjusting aiming like the torp would have.
Actually there are artillery shells with fins on the nose to guide it along a certain path such as trying to hit a target behind a mountain where your conventional cursing arc could not reach. Those do exist but its probably easier to have a fighter jet come over and just bomb it so we don't see much about it.
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Re: Pacific Rim- how to do it more efficiently?

Post by JI_Joe84 »

Also Q99, if the breach really remains fixed in location then the range disadvantage is not a problem. We just camp the breach.
Now the question is what do the kiju do??
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Re: Pacific Rim- how to do it more efficiently?

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You'll notice that Q99 calls anything aside from what we see in the movies speculation. He uses the term negatively when talking about other applications for RimTech and other near future tech that we're currently working on. Yet he uses just as much speculation to ensure that any plan you try will be defeated by some never seen Kaiju, ie. "They've adapted to Jaegers so they can adapt to supersonic penetrators." or "This one's head was shaped like a battering ram, he must have been designed to break down the Pacific Wall." or "Kaiju bones could break drill bits mounted to a torpedo." He also wants to use numbers for Jaeger costs taken from secondary sources, movie promotional material and the novel, while ignoring the bits that he doesn't like such as Kaiju and Jaeger weights.
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Re: Pacific Rim- how to do it more efficiently?

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It occurs to me that assuming you magically could make the supercavitation rocket torpedo work at 35,000ft depth, the static pressure of the gas would already have to be to the tune of 15,000psi just to withstand the water. The pressure the nose would actually experience moving would be many times this. Typical rocket motor firing chambers are to the tune of 1000psi for comparison! The torpedo would basically be rocketing around inside of a very powerful explosion.

A weapon like that shouldn't even need to hit the target to cause major damage. Just passing beside it would leave a constant explosive damage trace as the gas bubble expands and collapses. The amount of energy involved in this is of course rather linked to why it wouldn't work in real life, even if you could solve the gas control issues.
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Re: Pacific Rim- how to do it more efficiently?

Post by Venator »

Actually, on the topic of "if you could solve"/"why this wouldn't work in real life" and what assumptions we can and can't make...

We know they have the engineering chops and material resources to think that walling off an entire continent was a viable solution (even if the wall itself was rubbish). Compared to Australia (~36,000km of coastline), why not just make a ~11km deep wall around the breach, pump out the water, and ignore the issues of water entirely?

Something like JJ's railgun idea then becomes very attractive in that situation.
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Re: Pacific Rim- how to do it more efficiently?

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Possibly because it's virtually guaranteed that kaiju will be coming out of the breach directly and interfering with construction, whereas they'd only interfere with the construction of the Wall occasionally in specific locations?
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Re: Pacific Rim- how to do it more efficiently?

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Jub wrote:You'll notice that Q99 calls anything aside from what we see in the movies speculation.
Yes...? 'Something outside of what's established is, by definition, speculative.

And there's kinds of speculation. "We've seen them do something similar, so they can probably do this," different designs, same tech, is the type of question being asked here. "We haven't seen them do something similar here, but they could win if they did this," is a different type of speculation.
He uses the term negatively when talking about other applications for RimTech and other near future tech that we're currently working on.
Not negatively, so much as a different question than, "What can you do with what we see?".

Because if we're adding other supertechs, there's a gigantic array of possible supertechs, and "Oh, it'd be so much easier if they just had (something new)," is way too broad an area.

Considering what to do with constraints on technology is a challenge one has to think around. Considering what to do without constraints on technology is, well, rather easier, and is now not a question of "what do you want to add?". It's more writing a new story using new parameters. Which is a perfectly fine thing to do! I encourage anyone who wants to make a fanfic along those lines to do so ^^ It's just no longer talking about what's possible with what is definitively established.

Yet he uses just as much speculation to ensure that any plan you try will be defeated by some never seen Kaiju, ie. "They've adapted to Jaegers so they can adapt to supersonic penetrators."
We know they're purposefully designed. We can consider what other designs are possible because we're told they do this. When we're told that someone is actively altering designs to find better responses, one must factor in that they'll do so. It's not borg-like immunity or anything, but altering designs is something they do. Redundant organ, thicker shells, better maneuverability.

And I will note, the purpose of the thread is to speculate what approach we would take as the Kaiju makers. That's the question being asked. What alternative approaches in building kaiju would be more effective?


Also, Trespasser took plenty of supersonic penetrators vs the military, I'm pretty sure ^^;

or "This one's head was shaped like a battering ram, he must have been designed to break down the Pacific Wall."
^^;; You don't see the difference between speculating the purpose of something seen in canon, made by people we know to be purposefully designing things (i.e. we absolutely know 100% it was designed with a purpose, and the strategic goal, we're just left to figure out what the specific reasoning of the designs are. Mostly guessing based on what they're shown to be good at), and adding something outside the shown technology of the movie?
or "Kaiju bones could break drill bits mounted to a torpedo."
Because that's a known super-hard material in large quantities, and we have seen the bones in action. That's... not speculative at all. Drillbits wear out by nature, anything super hard will wear out many kinds of drillbits. Gipsy's sword with Gipsy's weight behind it couldn't pierce Scunner's skull, so, do we really think a little drill can get through?

And if you think we can make such a thing *with* shown materials and techniques, that's good! Explain reasoning.

He also wants to use numbers for Jaeger costs taken from secondary sources, movie promotional material and the novel, while ignoring the bits that he doesn't like such as Kaiju and Jaeger weights.
Note how with weights/mass, I'm taking visual performance over stated numbers, as the two are obviously contradictory. Anything else, I'll take secondary sources that don't contradict anything no problem.

I think you just like threadcrapping on scenarios rather than indulging them, honestly. I'm going to focus more on people who try and engage the topic rather than complaining about it.
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Re: Pacific Rim- how to do it more efficiently?

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JI_Joe84 wrote:Also Q99, if the breach really remains fixed in location then the range disadvantage is not a problem. We just camp the breach.
Camping the breach revolves around the fragicide problem one way or another.

We're talking nuclear torpedoes, right? So if one camps too closely, you lose your camping installations whenever you get a hit, and as we've seen, one really does need a good close hit to work. So you gotta be at some distance, which conversely, gives a freshly-emerged Kaiju time to start swimming and evasions and there's less surprise in the camping.

The bigger the warhead, the further away you gotta launch it from for safety (or not even safety, so much as 'so disrupted that it can't fire a second shot), and the more room to maneuver and warning the target has.

Which can be countered to an extent by putting more launchers, but considering you need a 3-D dome, how many is feasible to build around at a distance?

Now the question is what do the kiju do??
Hm... my thinking is more aquatic focused Kaiju, small and fast, especially when one got to multi-event.

Like, instead of a large kaiju, what if there were two half-sized Eel shaped kaiju, deployed one after another. They come out and swim in different directions, or even parallel, at enough distance that only one can be hit at a time even if one *is* hit. The other can ride out in the clearing created by an attempt to hit one. After a blast, everything's effectively blinded down there, so any kaiju that survives an attempt can either dash for freedom, or dash to take out other launch sites while they're scrambled.

An undersized kaiju would be more vulnerable, but could dominate the seas with speed.


Or... oh, would it be possible to disrupt an incoming torpedoes' course with a shockwave, kinda like a whale's sonar pulse...? Well, probably not.... hm, Otachi had very strong acid. How about a kaiju that swims directly away from a torpedo, but leaves acid clouds in it's wake ala an octopus? Torpedo goes through, gets acid on it, and is damaged/destroyed. Cephalopod defense ^^ That'd be a possibility for a good sized kaiju.

Oh, a kaiju that drops scales or even limbs to give false targets and things for the torpedo to run into would be a possibility.



Venator wrote: Actually, on the topic of "if you could solve"/"why this wouldn't work in real life" and what assumptions we can and can't make...

We know they have the engineering chops and material resources to think that walling off an entire continent was a viable solution (even if the wall itself was rubbish). Compared to Australia (~36,000km of coastline), why not just make a ~11km deep wall around the breach, pump out the water, and ignore the issues of water entirely?

Something like JJ's railgun idea then becomes very attractive in that situation.
Daaaang is that an impressive engineering project! (And 11km? Yikes, even with the weaponry involved, I think you can go smaller! Once the water's out, there's less shockwave/pressure factor) Yea, that'd certainly eliminate the 'swim away' problems and natural protections of water.

Like Simon_Jester mentioned, the big problem is going to be construction interference. The longest wait between kaiju is 6 months- and that's after the first, before it's even know a second will come. I would say, realistically, you have maybe 4 months to build it if it's an ASAP thing and you begin right after an event while the timespan is still longish. Later on, you'll have a month or less.
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Re: Pacific Rim- how to do it more efficiently?

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Q99 wrote:Like Simon_Jester mentioned, the big problem is going to be construction interference. The longest wait between kaiju is 6 months- and that's after the first, before it's even know a second will come. I would say, realistically, you have maybe 4 months to build it if it's an ASAP thing and you begin right after an event while the timespan is still longish. Later on, you'll have a month or less.
You would build it as numerous giant cassions which are towed to the site and then sunk. Supertankers full of waterproof concrete can seal the joins.
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Re: Pacific Rim- how to do it more efficiently?

Post by Q99 »

How long would it take for even the pump-out-the-water part, I wonder?
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Re: Pacific Rim- how to do it more efficiently?

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Q99 wrote:
Venator wrote: Actually, on the topic of "if you could solve"/"why this wouldn't work in real life" and what assumptions we can and can't make...

We know they have the engineering chops and material resources to think that walling off an entire continent was a viable solution (even if the wall itself was rubbish). Compared to Australia (~36,000km of coastline), why not just make a ~11km deep wall around the breach, pump out the water, and ignore the issues of water entirely?

Something like JJ's railgun idea then becomes very attractive in that situation.
Daaaang is that an impressive engineering project! (And 11km? Yikes, even with the weaponry involved, I think you can go smaller! Once the water's out, there's less shockwave/pressure factor) Yea, that'd certainly eliminate the 'swim away' problems and natural protections of water.

Like Simon_Jester mentioned, the big problem is going to be construction interference. The longest wait between kaiju is 6 months- and that's after the first, before it's even know a second will come. I would say, realistically, you have maybe 4 months to build it if it's an ASAP thing and you begin right after an event while the timespan is still longish. Later on, you'll have a month or less.
I probably should have said 'tall' rather than 'deep' (as in, 11km give or take from the sea floor to the surface).

Construction interference occurred to me as the biggest hurdle. You have to build at least the bottom of the wall very fast, but also either durable enough to survive the (presumably nuclear) anti-Kaiju measures, or far enough from the breach (more materials > slower construction) to not have to worry about it.

Maybe something like this, actually -
Starglider wrote:You would build it as numerous giant cassions which are towed to the site and then sunk. Supertankers full of waterproof concrete can seal the joins.
Q99 wrote:How long would it take for even the pump-out-the-water part, I wonder?
An 11km by 1km cylinder would contain 8.64e9 cubic meters > 8.64e12 liters of water. According to The Internet (http://gizmodo.com/5800072/the-worlds-l ... ery-minute), our most powerful modern pump moves 568,000 L/s of water... for approximately 176 days of pumping.

Now assuming you can field 4+ of those pumps you can get it down to a month or two, but you'd still have to budget for killing at least one Kaiju inside the completed structure for safety. Probably want to incorporate run-off valves so you don't blow up your own wall with overpressure.
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Re: Pacific Rim- how to do it more efficiently?

Post by Gaidin »

Q99 wrote:
Jub wrote:You'll notice that Q99 calls anything aside from what we see in the movies speculation.
Yes...? 'Something outside of what's established is, by definition, speculative.

And there's kinds of speculation. "We've seen them do something similar, so they can probably do this," different designs, same tech, is the type of question being asked here. "We haven't seen them do something similar here, but they could win if they did this," is a different type of speculation.
Coming up with a different use for similar technology isn't a stretch. We pretty much do it every day. It's a fairly legit question. What else could they have used the Jaeger level research on and made this easier. Not the neural link, mind you. Though maybe there's a use for that in cases. A lot more went into that. The material research for the armor. The hydraulics. The electronics. The heavy weaponry for a few of them. The power systems. I'm sure I'm forgetting a lot. And that's not counting all the support systems they had to come up with or logistics. You think using that stops at the Jaegers? They should've been using that everywhere.

Establish a sort of protocol for a line in the sand where they fight. Kaiju got past a Jaeger you say? Launch emergency advanced bomber squadron capable of dropping a payload kinda like those bombs the Australian Jaeger was launching out of its chest(if likely lighter) before it gets closer to shore to soften it up if necessary for a secondary. If that doesn't destroy it outright.

I guarantee you, if they still wanted to use Jaegers to fight these things, they'd have lost a helluva lot less if it wasn't just Jaegers.
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Re: Pacific Rim- how to do it more efficiently?

Post by Sea Skimmer »

So guys, you know foundations are a thing right?

All of this would require that the ocean floor is strong enough to support the mass of an 11km tall wall that is itself strong enough to withstand actual square kilometers of ocean current pressure. Which is profoundly unlikely to be true, and certain not to be true without putting in a very deep foundation. And I would suggest that the time required to put in tens of thousands of deep pilings into the bottom of Challanger Deep while under monster attack might be so high that spending twenty years to FREEZE THE OCEAN from the bottom up and then tunnel into that, using I dunno, a giant a liquid ammonia pipeline from the shore would be as or more reasonable.

Mountains only get as tall as they do because the ground is actually constantly squishing under them in slow motion. That kind of reaction will not be favorable to suddenly, in geological scales, dumping something like 5 trillion tons of concrete onto a small area. Also concrete isn't strong enough to self support over that kind of height. Not even close. How much for the magic alien tech concrete?
Venator wrote: An 11km by 1km cylinder would contain 8.64e9 cubic meters > 8.64e12 liters of water. According to The Internet (http://gizmodo.com/5800072/the-worlds-l ... ery-minute), our most powerful modern pump moves 568,000 L/s of water... for approximately 176 days of pumping.

Now assuming you can field 4+ of those pumps you can get it down to a month or two, but you'd still have to budget for killing at least one Kaiju inside the completed structure for safety. Probably want to incorporate run-off valves so you don't blow up your own wall with overpressure.
I dunno where they got the claim that's the biggest water pump in the world from, 5000hp is nothing. I know of ones which are rated for 10 MWs in the world, such as the ones for that giant Tokyo flood control tunnel system (CFM56 based turboshafts for power) and that's not counting the water jets on ships or certain pumped storage hydropower plants that are much greater in turn.

You are forgetting something very important though. If you pump out the water through the wall you have to fight up to about 15,000psi of backpressure on the outlet near the bottom. If you pump it over the top then you have to make up to 11km of vertical lift! Both of these requirements would enormously increase the required pumping power compared to that Mississippi pump which is only doing a few dozen vertical feet of lift. Pumps don't have static output ratings.

Realistically through any pumping system would need to be multiple pumping stages to get so much pressure at a useful flow, and probably a hybrid of methods. Pump out the upper water through the wall, and below a certain point lift it and then push it out at a depth where the backpressure is much less. It also might be worth it to try to start evaporating some of the water into steam with all the pump waste heat and pipe the steam to the top. But I think this whole idea is epic dumb anyway.


Edit: looked into water pump more and Polysci is not only wrong about it being the most powerful pump in the world, they have in fact underrated its actual pumping power because they suck that hard. Also the complex said pump is at has eleven of the things in a row.
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JI_Joe84
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Re: Pacific Rim- how to do it more efficiently?

Post by JI_Joe84 »

Q99 wrote:
Venator wrote: One thing that always bugged be about Kaiju was that they seem absurdly optimized in their defenses - they shrug off tons of conventional ordinance, survive repeated nuking, and yet blunt-force trauma and the occasional stabbing work wonders. Ignoring writer's fiat and inconsistent science and taking it at face value...
I will note blunt force trauma only ever stuns them from what we see- it's plasma cannons, missile volleys, or blades to vitals that do the killing. Otachi got cuts from Otachi, thrown, punched by Cherno, combo-punched by Striker, boat-batted by Gipsy, and while it took some time to shake off, each of those attacks were shaken off until it got a limb sliced off and it fell from super far.

And there's some variety in defense. Some have exoskeletons, some endoskeletons, but it is all the same material so, yea, there's some aspects of the defense which seem to be set.
U will note stryker took down the wall breacher with its chest missiles. Physical impact blunt force trauma (lots of it) to the head and chest vitals took that critter down for good. How can you miss that? It's only the second battle scene in the movie!
Why not try lamprey-style torpedoes - decent but not outlandish propulsion, thermal guidance and a drill. Find warm thing > drill until it stops being warm. Build by the shipload.
Hm, couldn't it use it's limbs to slap itself, much as we do a mosquito? And the bones may chew up drillbits...
Hhhm this sounds like supposition with out any evidence behind it at all. U need to show evidence why this won't work.
Q99
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Re: Pacific Rim- how to do it more efficiently?

Post by Q99 »

Gaidin wrote: Coming up with a different use for similar technology isn't a stretch. We pretty much do it every day. It's a fairly legit question. What else could they have used the Jaeger level research on and made this easier.
Agreed, and using the same tools in a toolbox in different ways is quite interesting. If you need to go a fair bit different the shown technologies though, and want tools outside the available box, that's kind cheating, though, and opens the limits so broad it doesn't say much about what they could've done (if there's no limits, you can just say, 'giant orbital laser canon, done.'). Figuring out stuff with tools at least close to what they have, that are either RL possible or definitely PR possible, is the challenge.

I'll note that the original post question is more applying this type of question to the Precursors- What other uses and approaches could be done with the kaiju-making tech?
Not the neural link, mind you. Though maybe there's a use for that in cases. A lot more went into that. The material research for the armor. The hydraulics. The electronics. The heavy weaponry for a few of them. The power systems. I'm sure I'm forgetting a lot. And that's not counting all the support systems they had to come up with or logistics. You think using that stops at the Jaegers? They should've been using that everywhere.
Though it's not rare for their to be logistic bottlenecks for new technology. Most of the stuff, like the power plants and weapon, were huge and thus would require huge facilities to make, and not all of it would scale down (though some stuff, like the armor, can obviously be made in smaller amounts). Filtering through to small scale stuff and ubiquitousness normally takes time with technology. So, there's going to be some limits in how much can be deployed in the short run, whatever the approach used.
Establish a sort of protocol for a line in the sand where they fight. Kaiju got past a Jaeger you say? Launch emergency advanced bomber squadron capable of dropping a payload kinda like those bombs the Australian Jaeger was launching out of its chest(if likely lighter) before it gets closer to shore to soften it up if necessary for a secondary.
Yea, that's a logical and straightforwardly effective.

I will note that when not close to shore, Kaiju spend most of their time submerged, so you will almost certainly have to hit 'em within the city a lot of the time, though.

JI_Joe84 wrote: U will note stryker took down the wall breacher with its chest missiles. Physical impact blunt force trauma (lots of it) to the head and chest vitals took that critter down for good. How can you miss that? It's only the second battle scene in the movie!
Point, but it did take a repeated series of hits from very large explosives. The punches never did more than stun a target.

Hhhm this sounds like supposition with out any evidence behind it at all. U need to show evidence why this won't work.
You need evidence that slapping works? Really? ^^;

Look at anyone deal with a mosquito.

Heck, on drilling, didn't Hannibal say it took so long to drill through a skull the stuff on the other side would rot by the time they're done?
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