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For a robot built in the future, powered by a nuclear reactor, and controlled using some sort of neural interface, a Jaeger’s combat tactics are surprisingly primitive. Yes, they have plasma casters and missile launchers, but most of the time, the Jaegers fight with old-fashioned punching and brawling. They talk about the Kaijus’ thick skin and how conventional weapons cannot penetrate it, yet the most effective weapon in the movie is a sword that can cut through entire limbs with ease. There’s a reason why modern soldiers don’t fight with swords. Why fight up close with a sword when you can stand far away and propel a sword at high velocity towards your enemy?
A rocket punch from a Jaeger has similar kinetic energy to a Boeing 747 at 60 mph, at 125 MJ of energy. This is approximately equivalent to 30 kg of TNT. This may seem like a lot, but the MOAB, the largest non-nuclear bomb in the U.S.’s arsenal, has a blast yield of 11 tons of TNT, or almost 10000 kg. A MOAB would do damage similar to 300 rocket punches, all at once.
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We don’t need expensive, physically impossible robots to fight giant monsters. Popular Mechanics laid out a strategy of using current day helicopters and bombers to counter the Kaiju threat. These bombers could deploy payloads such as the MOAB, a bunker buster bomb, or a continuous hail of carpet bombs. A MOP is a bunker buster which is claimed to be able to penetrate 60 m of reinforced concrete. This would appear to be a great weapon to use against the Kaijus’ thick skin.
Here’s another idea. We know exactly where the kaiju are coming from, so why not surround the location with tons of naval mines? Sure, a single naval mine would probably not be very effective, but a minefield of them should at least slow a kaiju down as it swims toward the shore. You might even be able to pack a MOAB into a naval mine, which could potentially cripple a kaiju before it was able to do any damage.
If you extend the time frame slightly into the future, there are more weapons available that could be potentially even more effective. One idea is to use a railgun. Yeah, the deus ex machina in that other giant robot movie.
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These weapons use electromagnetic propulsion to send a projectile at over 10 times the speed of sound. Current railguns have kinetic energies in the 10-60 MJ range. Even if this is not as much as a rocket punch or a MOAB, the railgun has many potential advantages. First, given correct projectile design, a railgun would almost certainly be able to penetrate a Kaiju’s skin and deal damage to internal organs. Second, railguns have tremendous range and accuracy. With a range of 100 miles, they could engage Kaiju well clear of any potential danger. With the money spent on Jaegers, you could build a large battery of hundreds of small railguns, or develop a massive railgun with even greater kinetic energy.
Finally, there is my favorite idea: kinetic orbital bombardment, also known as “Rods from God.”
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Under this concept, massive projectiles would be housed in orbital satellites. When a kaiju is detected, a projectile would be released from orbit, and as it falls it would accelerate to velocities as high as 10,000 m/s. This would result in energies of over 100 tons of TNT – 10 times the yield of the MOAB! That’s 3000 rocket punches delivered at once. Moreover, since it is deployed from space, it could easily target the kaiju and eliminate it as soon it is detected, far away from the coast.
If these weapons were to succeed, the consequences would be clear: If they’re so effective on kaiju, they’d be even more effective on human armies! Whoever was in control of an orbital bombardment satellite would be able to quickly deploy 100 tons of TNT to major targets all around the globe. Sometimes, it’s scary to see just how good we have become at using physics to create ever greater weapons of destruction. But at least we know we’d be safe from giant monsters traveling through an interdimensional portal. Probably.
I had the idea to use “rods from god” as well!!! I was watching Pacific Rim on a flight back from vacation this summer and I couldn’t help but think that was the best solution. They’d be extremely powerful, powerful enough to penetrate nearly anything, and wouldn’t give off radiation like a nuclear warhead. Literally the ideal solution.