Making a Cruise ship into a megadungeon

[Shades of Eternity]

I really like the drone pod idea.

Did part 2

O.R.C.A. – The Terror of the Seas - Part 2 - Atlas Reach - an Overview

History An Achievement of Pre-Revelations Engineering, Atlas reach is a gargantuan nuclear cruise ship, which travels in pursuit of obta...

www.hodgepocalypse.com

It's basically a rough overview.

I'm then going to try to see if I can flesh it out floor by floor.

anything missing?

 

[aramis erak]

Any suggestions for what an arcology at sea WOULD look like, or how it could be adapted to a dungeon? Some constructive feedback/your suggested alternate approach might be useful to the OP.

The majority of designs look largely like a point down cone, with the majority of the crop space below sea level either lining the main cone or in pie-dish shaped additional components. All of them have sidewalls raised to 100m or more above sea level. Articulated interconnects under surface. Additionally, aquaculture projects float in a ring of life around them. Given the large sizes (typically, the proposals I've seen put the main hab cones at 1-2 km across, 0.3 to 1 km deep, and surrounded by aquaculture to 3 km radius. Boat launches and cargo porting are outside the actual cones, too.
The walls of the cones are typically shown as 30-50m thick, so, think an inner side hab, an outer side hab, both say 10-15m of the thickness each, and another 7 to 15 m of no-outside-access facility. Think schools, shopping, administration.

THe obvious need for compartmentalization in case of storm or impact would mean fairly regular patterns. Lowest risk housing is no outside edge, but that's also not good housing for humans.

The inside of the cone gets used for growing the terrestrial foodstuffs. The nutrient needs of those will probably require composting. There will be a constant influx of materials from aquaculture projects.

The effluent from the sewage system will likely need to be composted; radiation-sterilize it, then add it to a cultured composting in a subordinate (possibly even submerged) structure.

The other big form is a series of seafloor domed cities. Most of the domes would still need to make food....

Note that cruise ships largely just dump effluent. Which means that they can't draw water if they aren't moving, since it's contaminated by their own sewer dumping. THey have many small cabins, but no room for manufactuing, no room for growing, and no structural strength for significant armamments

The "cans" (more properly, "turret mount") which big ships' guns fit into are structurally affixed to the keel; if they weren't, they'd crack the decks during a longish fight. The guns recoil within the turret head; the turret head rotates inside a can-shaped inset. The inset interacts with a structural fitting tied to the keel, so the guns recoil operates against the whole-hull mass. This is all to reduce self-damage from guns. (Several late 19th C warships had huge issues with self-damage from oversized guns...)

Most sea arcologies will have defenses - but they're more likely to be drones, not guns,

 

[Dannyalcatraz]

Most sea arcologies will have defenses - but they're more likely to be drones, not guns,

I’d think missiles, rockets, torpedoes- all essentially recoilless weapons- would be in the array. Heck, since we’re talking arcologies, why not lasers of various wavelenghts and LRADs?

 

[aramis erak]

I’d think missiles, rockets, torpedoes- all essentially recoilless weapons- would be in the array. Heck, since we’re talking arcologies, why not lasers of various wavelenghts and LRADs?

With the exception of LRADs, which I don't recognize as a term...
Torpedoes still require a weak spot in the hull (the tube), and are NOT recoilless, since they've a pressure wave to help them exit the tube.
Deck torpedoes work well only when one is already pointed generally toward the enemy. And again, it's a projectile which has to be thrust out of the tube. Not recoilless.
Torpedoes are low recoil.
Rockets/missiles (same thing) do have very low recoil, but produce a prodigious amount of flame. The needed thermal mass is bulky. (Not so much heavy, but bulky.) And, unlike cannon, the propellant can be cooked off by a laser...

Lasers are not, at present, capable of the ranges of a 5" QF cannon (since many can exceed horizon - 11 miles came up on a quick google) No naval laser is going to exceed 5 miles - because the curvature of the sea has a limit of 3.1 miles or so. And while they are almost entirely recoilless (meaninglessly low except in an orbital/n-space context), they're going to require more mass per joule delivered to target than any cannon due to the need to use capacitance banks and major amounts of power generation. And feeding those capacitance banks needs a lot of energy at a roughly 30% efficiency; the capacitance to laser energy is also a similar rate... so about 9% efficiency from the generator, which is itself a 30-50% efficiency, so are' to to 3 to 4.5% of fuel efficiency into the laser... while we can get 30-50% or so with naval canon. (variety of factors I can't quantify.)
Further, Lasers dissipate over airspace both due to beam divergence and atmospheric scattering. At sea, they add spray to the particulat impediment...

So, canon are, largely, the most efficient use. Faster to rearm than missile systems. Easier to build, as efficient on fuel to joules of impact, can carry the same warheads... the drawback to guns is the strongback and can - not readily refittable.
Missiles ae harder to rearm, more risk of cooking off in launcher, but slightly longer ranges... but slower speeds. Most naval cannon are supersonic or hypersonic; most missiles run transsonic to supersonic. Gun shell is a smaller target than a missile, but both can be hit by modern CIDS/CIWS defensive automated defense cannons.

Defense turrets should be a mix of close in laser turrets (for sustainability) and very rapid fire small caliber autocannon (15 to 30mm hypersonic)

Note that CIWS have a significant recoil - they stress their mounts. So they are a significant maintenance factor, and work best when attacked to a localized strongback affixed to major bulkheads, if not to the casements part of the major turret cannon.

 

[Dannyalcatraz]

I’m not say8ng any one weapon would be used to the exclusi9n of others. I’m suggesting that aquatic arcologies would probably utilize a variety of weapons to complement the drones.

LRAD = Long Range Acoustic Device Essentially, they’re a focused sound device that can be utilized as a short-range less than lethal weapon. Current LRADs can enable highly intelligible vocal commands to be heard at approximately 2000m. But they’re also capable of delivering debilitating sounds (ear pain, nausea, vertigo) out to about 700m. Closer in, the focused sound can permanently harm if maxed out.

….all while being only moderately noisy to those outside the beam of sound.

They’re in use with some police forces and certain military vehicles. I know the Navy has some of the beefier ones, but I’m unsure if they’re permanently affixed or are mission-sensitive.

 

[aramis erak]

I’m not say8ng any one weapon would be used to the exclusi9n of others. I’m suggesting that aquatic arcologies would probably utilize a variety of weapons to complement the drones.

LRAD = Long Range Acoustic Device Essentially, they’re a focused sound device that can be utilized as a short-range less than lethal weapon. Current LRADs can enable highly intelligible vocal commands to be heard at approximately 2000m. But they’re also capable of delivering debilitating sounds (ear pain, nausea, vertigo) out to about 700m. Closer in, the focused sound can permanently harm if maxed out.

….all while being only moderately noisy to those outside the beam of sound.

They’re in use with some police forces and certain military vehicles. I know the Navy has some of the beefier ones, but I’m unsure if they’re permanently affixed or are mission-sensitive.

Oh, those. They're not terribly effective except for deafening.
EMP weapons are more likely to be used.

Cannon are the best naval offensive weapon for sustained combat; mass drivers are not yet reliable enough to replace them, but will likely do so eventually.

Lasers, due to LoS and atmospheric diffraction, have little place as offensive naval weapons. They have a lot of place as point defense, but they're still not efficient enough to match the Phalanx CIWS in the short run. Superconductor-based capacitors may be able to change that... And for CIWS, short run is the important one.

Note: The average naval battle starts beyond the horizon since the advent of the naval spotter with a radio... those early CA, BC, and BB carried seaplanes served as forward observers for the indirect fire of cannon. The last 40 years, missiles have had a lot of play, but cannon are harder to intercept and less likely to be a total miss if hit by CIWS.

Current trends in naval warfare have resulted in BC and BB falling out of service; their flagship role has, in the US, UK, USSR, and Commonwealth, been replaced by cruiser-sized and BB-sized carriers; ship-launched missiles are falling out of favor due to the much wider use of CIWS, including by the PRC and USSR.

The USN is moving to drones rapidly; any floating arcology is going to use drones and aircraft to keep threats far from the arcology. Once a potential aggressor is within cannon range, it's already too late. A DD with dual 5" QF can drop a pair of 30kg shells every 3 seconds, burning a a thousand plus CIWS shots or more. A line of 5 such DD? the CIWS will wind up either overwhelmed in part or burning ammo prodigiously; 10 shells per 3 seconds.... the rain of shrapnel is going to start infalling. And a functional self-supporting arcology is going to need a lot of surface area with minimal protections, so as to manufacture foodstuffs.

A converted cruise ship can't handle cannon, can't handle CIWS mounts other than laser type (the decks aren't resilient enough, as they're designed only for passengers), can't handle the battery/capacitor weight near the L-CIWS, can't handle the needed armor for shrapnel proofing (the issue isn't enough flotation for the batteries and armor, but where the center of mass will be; it will be moved above waterline, and so severely increase capsizing risk. If the battery banks are below waterline, that makes them much less durable.)

It's easier to convert military shipping to a town, than a cruise ship to combat useful...