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For $10,000?

Today?

$10,000 to build something with a range of several hundred miles (any closer and the launch platform would be detected before they all launched).

$10,000 to build something such that 90% of them carry sufficient, collective explosive payload to cripple or destroy a carrier.

$10,000 to build the autonomy needed to get around jamming, GPS hijacking, and to track a moving target. I guess, once they're close enough, they can spot the shape of a carrier pretty effectively. But depending on their launch distance and speed, the carrier may be wildly off from where they expected it to be.

If electronic countermeasures weren't a concern, the swarm could spread out, locate the target, and relay coordinates to all others in the swarm. But jamming makes this a difficult proposition, after the first attack.

Then, this, if it works, is a $100,000,000 attack on a single carrier group. And a literal sunk cost at that, these won't be recoverable and reusable.

> The way to kill a carrier strike group today is to make them run out of bullets.

Nuclear powered vessel (all latest carriers?) + lazed weapon = you'll never run out of ammo.

http://www.theguardian.com/us-news/video/2014/dec/10/us-navy...

"The US navy demonstrated its new 30-kilowatt laser weapon system in the Persian Gulf, near Iranian waters. The device, which is 30 million times more powerful than a laser pointer, is capable of targeting mounted weapons systems on fast-moving boats, and destroying drones in mid-flight. According to the navy, a much more powerful 150 kilowatt system is currently in development"

This was two years ago.

Railguns with inert slugs. The things will have a 200+ mile range and you can store and reload without having to worry about explosive propellant. Lots more bang for the buck. Lots more ammo storable onboard.

Also something the US Navy has!

https://www.youtube.com/watch?v=eObepuHvYAw

These are the real game changers for destroyers and cruisers. The combination, lasers and rail guns, is probably going to be the standard of what you have to deal with in 15 - 20 years.

I did some ballpark calculations on the subject. You would need about 800kW laser to reach parity with M61 Vulcan autocannon.

I compared how much you need to melt aluminum with how big volume dent you can make to steel with 20mm round traveling 1000m/s. The energy you need to melt aluminum is considerable, and autocannons have pretty whopping rates of fire.

You need 0,05 second beam on target with 30kW laser to have the effect of single 20mm round. During that time M61 fires 5 rounds and incoming BrahMos missile would travel 50 meters.

You can claim that penetration is hardly needed. Then you can add bursting charges with programmable time fuses to those 20mm rounds. And you have high speed high accuracy shotgun.

It boils down to targeting. Both can do it if they hit in the appropriate time window. BrahMos does S-manouver at the close in range, but 500m before impact it moves straight. At this point it's trajectory is ballistic enough to hit anyhow. And it's kinetic energy is going to give you a bad day no matter what (~1000m/s and ~1ton weight, comparable shell from main gun of Iowa). During that S-maneuver you have to score or you're dead. Cannon rounds have long time of travel, you have to shoot when the missile is 2km away to hit it 1km away. The good news is that missile traveling that fast has to have turn radius of several kilometers.

In the future both close in possibilities are likely to be futile. BrahMos II has twice the speed and it's likely to have some stealth features. If you can't see it on radar, shooting it with laser is impossible. You can still see it on IRST, but shooting extremely hot beam of light towards it is going to fuck up your delicate sensors.

Edit: current best weaponized lasers have similar size, weight and range than M61. But lot less power. Increasing the range and the power at the same time is very tricky.

First your opponent would have to find the carrier. Easier said than done.

Next they would have to be able to target it with these drones. The drones would have to be fast, (otherwise the carrier has moved out of reach), long ranged (otherwise the airwing will neutralize the launchers) and completely autonomous (otherwise the carrier and its escorts will jam any comlinks.

If you think you could build such a weapon for $10K, good luck.

If my mission were to take out a carrier group, and I had a budget of $100M, I would go a slightly different direction.

I'd shop Alibaba for 300 hp diesel outboard motors, and rigid-hull hydroplaning inflatable boats with at least 2000 kg maximum cargo weight. Then I'd build some one-ton armor-penetrating bombs and 19 times that number of cheap decoys. My engineers would rig up the steering and throttle controls to some servos, connected to a system-on-a-chip, connected to some cheap sensors that could determine distance and direction to nearby objects and discriminate between big ship and little boat.

The software on the SOC would have a flocking/schooling AI that would maintain separation between vessels while seeking to maneuver the bows of many small boats into contact with any large ship. Any boat carrying a non-decoy bomb detonates it on contact. It would be about as complex as an insect brain.

For bonus points, the boats would be spitting flares, smoke, mylar helium balloons, and chaff everywhere as they approach. Perhaps a few would conceal a conventional torpedo.

As you say, the hard part is getting the weapons to the targets. With a setup like this, you really need to have the carrier group come to you. The inflatables can certainly outrun a carrier, but they have much shorter range. Perhaps the boats could be deployed by submarines?

I think each decoy boat could probably be deployed for less than $2000. The bomb boats would be that, plus the cost of the bomb. There would be no radios to jam. There's no particular reason the drones need to be airborne, other than for speed and maneuverability, and you're trading that in for sheer numbers (40000+) anyway. Besides that, it's a lot easier to float a one-ton bomb than it is to fly it, and it would do more damage at or below the waterline than on a deck.

If US carrier groups are not wargaming this type of scenario, they probably should, both as underway-at-sea and in-the-harbor attacks.

Are you sure the inflatables can outrun a carrier? Though the top speed is classified, it's widely acknowledged that a CVN can make 30+ kts indefinitely, and in sea states that would make inflatables untenable.

And "armor penetrating bombs" usually do so by one of two methods, kinetic energy imparted via gravity or rocket engine, or via something similar to an explosively forged projectile (like the fancier Iranian IEDs).

And there may not be any radios to jam (assuming your swarm can maneuver intelligently without communication), but that doesn't mean that your control servos etc are immune to jamming. The electromagnetic spectrum is pretty wide, and I wouldn't be surprised if this was something that couldn't be fried by a clever Aegis array. The wattage those arrays put out is pretty incredible.

An aircraft carrier displaces 100k tons. A fully loaded inflatable displaces maybe 2 tons, and can hydroplane. As long as the outboard motor is not damaged, an inflatable is definitely faster and more maneuverable than a carrier. The carrier beats the inflatable in range and seaworthiness, though, which is a significant advantage. So again, the major problem is how to get the inflatables close enough to the carrier in the first place. Inside a harbor or straits, you accomplish that via stealth or trap. On open seas, well... probably better to guess where the carrier group is going and wait for it there.

The threat of an attack like this can cause a carrier group to maintain an impassable cordon at a certain distance from hostile coastlines, just like anti-ship ballistic missiles. 500 guys can spend all night prepping and launching boats from transport trucks and a floating pier, and two can pilot the "flock leader" close enough to your ships that the attack behaviors can trigger.

As far as I know, you can craft a bomb using engineered shapes and controlled detonation timing to drive a lance of molten copper through a hardened steel armor plate. It does require a certain level of technical expertise and precision machining. That's why so many boats have decoys on them; too expensive to put bombs on all of them. But even so, the USS Cole attack used only 0.3 tons of dumb explosive and still opened a big hole. But it neither sank the ship nor damaged its keel, which is why bigger, smarter bombs are needed to take down a warship. You have to pierce through more than just the outer hull, otherwise the built-in passive defenses of a modern warship mean you only inconvenience the enemy for a few months, rather than putting their asset on the seafloor.

Couldn't you place all electronics inside a Faraday cage and ground it to a metal part in your hull? The steering and throttle can be done with purely mechanical linkages.

US aircraft carrier top speed is classified, but "in excess of 30 kts", typical inflatables top out at about 30 kts, though there are faster high-performance designs. I don't think it's clear that inflatables are faster than carriers, but they are more maneuverable (can change speed and direction much more quickly), which is more important outside of a long-distance chase.

You're not wrong but I don't think your chosen method of exhausting their consumables is practical.

Lets start with your 'bomb', its an aircraft with a 2,000 mile total range (you actually need 2,500 to cover cases where you are flying upwind) and a one ton payload capacity. So in flying circles that would be a plane with a 2,500 mile range and one ton capacity. Looking through the various aviation web sites, that would not be available for $10K. Even looking at something like the Spirit of St. Louis which had the range but no cargo capacity is $144K in todays dollars[1].

Then there is the question of speed, if these things are flying at 150 - 200knots (typical of a single engine turboprop) you don't need to shoot them down, you can just buzz them with a fighter yet and let the jetwash destroy them.

And then there is the question of engagement, the larger the circle you start with around the carrier group the more dispersed your incoming bomb-craft can be. But a circle with a radius of 2,000 miles (worst case) is 12,000 miles. There aren't very many circles like that on the planet where they have significant land on the circumference, other places mean that a bulk of your bomb-craft come from a smaller number of locations. And even a 100 aircraft taking off from an airstrip and heading toward the carrier groups is going to get a response to the airstrip pretty quickly.

But the fundamental thesis is sound, if you can overwhelm the defenses with an inexpensive and mass produced threat then you stand a better chance of getting to the carrier.

The only way I know of that you could do something was an idea Jerry Pournelle used to talk about which was a kinetic kill weapon that dropped from orbit. He called it "a crowbar with wings" which would detach from a satellite, re-enter ballistically, and using fins steer itself to the target where the energy from the kinetic impact would destroy the target. However, you then need these satellites with this crowbars and a communications network and launch facilities. So once again it is hard to surprise someone that way.

[1] https://en.wikipedia.org/wiki/Spirit_of_St._Louis

> a couple thousand pounds of TNT or other explosive, a basic aluminum airframe, control servos, a lot of fuel (enough for a couple thousand mile range), a small jet or even turboprop engine, a microchip, and a communications uplink. You could probably build this for about $10K with COTS hardware.

In other words, a cruise missile. They cost a lot more than $10k.

Still, not totally inconceivable -- being overwhelmed by "small and cheap" is a legitimate risk.

I do wonder about subs though, and how effective submarine detection capabilities are. Cruise missile swarms are brute-force and logistically difficult. Better to sneak up and stab them in the back instead? What about long-range torpedoes, perhaps even ones that could be prepositioned like mines, sitting underwater and waiting for a signal to go?

Considering how the USN has gutted their ASW capability in the last two decades, there's a chance that the greatest threat is an enemy submarine.

1. No ASROC 2. No Viking 3. No FFG-7 (and please no one tout the LCS) 4. No Sprucans

Just fielding a "couple thousand lbs" of explosive over hundreds of miles of water is very difficult and expensive. You also have to consider the survivability of a modern carrier. These things are built to take significant hits.

As of the mid-80's, they were designed to take 10 anti-ship missile hits and possibly survive with good damage control crews operating. Not sure what direction they went with the Gerald Ford and other ships after the Nimitz class.

The way to kill a carrier strike group today is to make them run out of bullets.

Western military planners seem to have a blind spot here. Back in the 1980's, it was projected that NATO would slaughter Soviet/Warsaw Pact forces in a ground conflict -- for one month. At which point, western forces would have run rapidly through their ammunition and supplies, then the advantage would return to the less technologically advanced east. (Then NATO would bring out the "tactical" nukes.)

It's probably economic in nature. It's profitable to sell the government lots of expensive toys with sexy capabilities on paper and high ongoing maintenance costs.

All of U.S. military doctrine is based on the assumption that manpower is the limiting resource.

That didn't even absolutely work in WWII.

Why would NATO run out of supplies?

Without bullets and beans, an army isn't worth much.

"Amateurs talk about tactics, but professionals study logistics."

Implied in his comment is that what little force actually deployed to Western Europe would have been dramatically outnumbered from the very start. In some categories the ratio was higher than 10:1. Until the mid 80's, we'd have been lucky to avoid crossing the nuclear threshold had the balloon gone up.

There was the Polder Gap. We had plans to collapse mountains into the mountain passes wth nukes to try and slow down the Warsaw Pact forces.

Fulda Gap maybe? This is really a wide open plain, not really a mountainous region.

If we went nuclear first (and odds are the Soviets would have beat us to the punch), SIOP was pretty broad and the idea of containing fissiles to the battlefield never had much credibility. Pershing and the GLCM were deployed so that NATO could easily and reliably hit deep into the USSR with European based weapons.

Fulda Gap maybe?

Yes Fulda gap. I mis-membered it. (It was a JROTC class in the 80's!)

After WWII, the rate at which weapons could use ordnance increased. In general, soldiers and weapons systems could move faster, fire faster, and engage more targets at greater distances. Mobility expanded and became even more important.

In general, greatly increased firepower and more advanced machines require lots more logistics. (By that measure the Soviet T-33 was superior to the German Tiger. It was more reliable and required less logistics for amount of firepower.)

At Kursk, that proved true. Numbers won.

>What happens if you send in 10,000 flying bombs simultaneously?

You're wishing into existence a capability nobody has or has had since the Soviet Union fell, and won't have for decades at least.

Beyond that, you're ignoring the ability of a carrier battle group to disrupt that kind of attack. The way to defend against that kind of thing is to destroy the launching platforms.

This sort of reminds me of the bikini island footage.

What is shocking with that footage isn't the devastation of the nukes but rather how damn robust the battle ships sacrificed are. Some of them never sank even after direct hits from a nuke.

So I have to think a carrier might just completely ignore your flying bots and let them attack/hit :)

No capital ships took direct hits during operation crossroads.

The closest was the USS Arkansas, at 170 yards from ground zero during the underwater baker test. It was lifted all the way to the vertical by the blast, before being pummeled into the sea floor.

Ahh that is right. I was going to double check that and I'm annoyed that I didn't. For some reason I thought some of them were hit directly.

Regardless the ships that did survive I don't think any humans would have survived on those ships given the intense shock waves (as shown by obliterated test sheep).

Don't forget about electronic countermeasures.

this drones you speak of would be pretty small and each one could be taken down with much smaller guns from air or sea. no need to use a missle, they are designed to take out heavily armored air/sea craft. thus i think it would take a lot more then 10k cheap drones to take out a carrier group.