Editing Toaru Majutsu no Index:MvM2 Depth3 (section)

===Part 5===

They had gathered in the CIC.

With Shokuhou, Hokaze, and Kobayashi there, the place looked a lot like a Shokuhou Clique hangout.

“The greatest threat of a ballistic missile comes from its altitude and speed,” explained Kobayashi from her usual seat. “They are literally sent outside the atmosphere where they can travel with zero air resistance until reentry, so their speed can reach a maximum of greater than Mach 10. That altitude also puts them well outside the range of any surface anti-aircraft weaponry. Shooting them down from the surface is just about impossible.”

“Are the ballistic missiles here girls too?”

“We don’t know. But the Harpoon and air-to-air missiles we’ve seen here looked like ordinary weapons, so presumably the ballistic missiles are also ‘just weapons’ with no girliness to them.”

That was good news at least. Mikoto breathed a sigh of relief.

Ballistic flight might sound complicated, but it could be thought of like a long throw in baseball. It was just that the top of that arc left the atmosphere in this case.

To shoot it down, you had to throw a rock from the side and hit the ball before it could land in the other player’s glove.

And with perfect accuracy.

“Ballistic missile defense is split into three stages,” said Mikoto. “First, shooting the missile down between when it is launched and when it leaves the atmosphere. Second, shooting the missile down while it is flying through space. Third, shooting the missile down between space and when its warhead detonates.”

“Of those, the first has the best odds of success,” said Shokuhou. “The missile is, after all, fighting against gravity, which lowers its speed. And its altitude is low. Also, it’s just one missile – the warhead isn’t splitting up and it isn’t weaving this way and that☆”

“Really? You know better and are testing me, aren’t you? We can’t use the first stage. The ballistic missile launch bases are at the center of the continent and we can’t get close.”

“That leaves us two options.” Shokuhou waved two fingers and winked with her back against the wall. “We use stage 2 and bring down the missile in space, or we use stage 3 and bring it down after reentry.”

“The third one has problems too. The Queen touched on it already. We do have a chance of shooting down the missile if it remains in one piece throughout its descent, but if the warhead splits, if it weaves hard in the air, or if it releases aerosolized fuel over a wide area, we cannot shoot it down.”

“That means we go with stage 2. We find some way to shoot down the missile while it’s flying through space.”

That would be a challenge if the warhead did split apart while in space, but in this case, they could assume every warhead was targeted at the Izanami and Izanagi on the ocean rather than targeting several cities spread out across the map. In other words, it would be an MRV, not a MIRV. Even if it did split apart, the speed and course wouldn’t change much until reentry. If they had a way to shoot down one warhead, the same defense system in the same position would be able to bring them all down.

“But how exactly do we do it?” asked Shokuhou with a shrug.

Mikoto ignored her. Did that spoiled pair of boobs just assume Mikoto would answer anything she asked?

“Kobayashi-senpai, when you say space, how high up are we talking?”

“Medium orbit…if that’s a real term. Geosynchronous orbit is at an altitude of 36,000km and space stations orbit at an altitude of about 400km, but ballistic missiles reach an altitude between those two. Somewhere between 1000 and 3000km, I think.”

Three thousand kilometers. That height was probably longer than the Japanese archipelago.

“Civilian space planes that take off in midair go up to around 100km, right? I assumed it would be more like that…”

“That idea isn’t entirely wrong.” Kobayashi suddenly contradicted herself. “Because ballistic missiles will fall back toward the surface. They drop in altitude on their own. If you want to intercept them in space but just outside the atmosphere, you can expect to contact them lower than the space telescopes and shuttles, but higher than the ballistic space planes. So between 110 and 120km.”

That sounded more realistic than sniping them from 3000km away.

Sniping them from 120km away would still be a challenge, though.

“All we have available to us are carrier aircraft,” said Shokuhou. “At best, they can maybe reach an altitude of 25km.”

It was a simple subtraction problem.

If they were assuming the120km figure, then shooting down the ballistic missile in space would need something with range of 95km.

“But our fighters are only equipped with small air-to-air missiles. It differs by type, but those have a range of around 20km, right? That’s 75km too short. Shooting down a ballistic missile flying outside the atmosphere with that seems like too great a feat to me.”

If they had a giant strategic bomber available, they could have used an ALBM or something, but they didn’t have what they didn’t have. Not that those could be used on a carrier anyway.

“I say flying a fighter up to ultra-high orbit is a good start,” said Mikoto.

“That’s not the hard part,” said Shokuhou. “The question is what we’ll shoot once we’re up there. It would need greater speed and force than any of the air-to-air missiles we have here.”

Again, they didn’t have what they didn’t have. They would have to construct something with what was available on the Izanami and the Izanagi. So they could remove a fantastic laser weapon with 100% accuracy from their list of options.

However…

“I might just have an idea.”

“?”