WW2 Japan gets the Asahi class Skyship (RAR!)

[Zor]

In this scenario in 1936 the Japanese find something off the western coast of hokkaido which it sturs to life. It begins mining resources from the sea floor, builds copies of itself, which build various specialized machines which build more machines which amount to a shipyard and ultimately begin building a spherical construct in June of 1939 which is completes in November of 1940. The machines are uninterested in ships or divers. Their only response to being shot at is to swim away and salvage fallen unit. The IJN cordon off the area and observes what is going on. The intelligence agencies know that something weird is going on, but in truth know little about it. Once it's completed it lifts off, hovers out of it's berth, flies out and dips into the water a short ways away. The IJN takes it, investigates it and names it the Asahi.

The Asahi is a spherical craft about 310 meters in diameter and weighing about 350,000 tonnes. It is made of steel, aluminum and composite materials and has an outer hull which is equivalent to 25cm of steel armor. There are numerous hatches along it's lower half and a few more on the upper half. It is powered by an trio of internal fusions reactor generating some 540 MW of power in total. Outside of some technical systems in has 24 decks. The lower decks are about 12 meters (including floor thickness), the upper decks are 6 meters and there is a central equatorial deck about 24 meters and is mostly empty space. This has four large hatches (each about 15 degrees of the circumference of the craft and 22 meters tall) on the equatorial deck. There are elevators for both cargo and people as well as secondary airtight bulkheads inside most of the decks (save the big equatorial one, which only has the extenal bulkheads) and environmental systems to maintain an environment up to maximum altitude where humans would be mostly comfortable. The top deck's roof is mostly a transparent dome and has some simple controls. It is capable of flying at speeds of up to 120 km/h, has a maximum altitude of 13 km and a range of 1,000,000 km before it needs to touch down in the water and extract more deuterium for it's reactors. It can only make water landings and it's computer will not let it touch down on land. It can carry up to 200,000 tonnes of cargo. Most of it's technical systems are handled by 0.5 meter long starfish like robots that ignore humans and it has some ability to manufacture new components. It has a RADAR system which it uses to construct a 3D map of the world around it for up to 300 km around it with several display screens on the bridge which can be set to search for certain general shapes.

The IJN realize that this vehicle could be an excellent carrier. As such it's given some quick modifications, some of them are basic such as installing bunks, showers, heads and kitchens for a crew of 2,500 and others include outfitting it with four 355.6 mm cannons, twenty 12.7cm cannons, 120 Type 96 25mm Gun and assigning it 120 A6M Zero fighters and 60 B5N Kate torpedo bombers with another 40 Zeroes and 20 Kates in reserve. This refit was completed by August of 1941. At the same time the shipyard which made the Asahi is at work making other craft like her every 14 months, though it too will have to be refit before it and subsequent vessels could be used as a carrier or transport.

What happens?

Zor

[Tandrax218]

so basically it gives you radar warning 300km radius and has 120 fighters on stand by on 13km ?

America loses its fleet in a meter of days if japan attacks and enters WW II, 120 km/ h movement speed is really fast for a huge bomb truck that could be created if the 200 000 tones of cargo is used for bombs... just hoer over a production plant, city / base and bomb it to dust...

+ another one is created in a little over a year ...

Japan dominates the world

[Elheru Aran]

Since it might be very hard to hide something like that... it could be considered a causus belli for the US or UK to pre-emptively attack?

[Batman]

Actually hiding that wouldn't be all that hard in the pre-spy satellite era. Just declare a no sailing/no flying zone around it

[Tandrax218]

and have ships patrolling said area shooting on sight ...

[Sky Captain]

It could be spotted by some recon flights, if Japan declared large no sail, fly zone and there are indications that something strange is going on there, US or Britain would be very tempted to make some reckon flights no matter what.

At WW2 era there would be no easy way to stop a skyship on a bombing raid. 13 km is too high for existing AA systems and fighters. Weapons designed to be effective against fragile aircraft would have no effect against such huge armored target. Japan essentially gets unstopabble bomber. Only plausible way to defeat it would be massive bomber attack while ship is at low altitude or landed in water. One issue would be producing enough bombs to arm it, but with such huge payload capacity just dumping rocks from high altitude would do a lot of damage.

[CetaMan]

13 kilometers is pushing it as a target even if they were to modify naval artillery. You essentially gave japan a bomber fortress nobody can reach, they possibly could within 5 years, but I doubt any allied nation will survive unless a super-lucky break is given (destroy current one while refueling, then push to shipyard and capture/destroy others)

[Tandrax218]

yes but probably the whole IJN would protect the sky fortress while it refuels, and a good portion of the IJA, fighter escort and stuff...
Plus no one said that the radar is turned off while refueling is underway...

#GoJAPAn #IJNVICTORY #BUSHIDOTOTALITARISM

[CetaMan]

Having the "whole navy" protecting it ensures that they are not doing anything else while it refuels, which given the size and mass could be a very extensive process. This leaves japan open to attacks and raiding forces, IE on the shipyard that is a massive target, or all their conventional shipyards and naval yards. The existence of such a device probably also pushes the allied nations into a frenzy, so it would be interesting to see if they redirect war efforts away from Germany and the African theatre. Wondering also how the other Axis leaders (Mainly Hitler and his staff) would respond to Japan finding what essentially is a piece of alien technology.

[LaCroix]

Having the "whole navy" protecting it ensures that they are not doing anything else while it refuels, which given the size and mass could be a very extensive process. This leaves japan open to attacks and raiding forces, IE on the shipyard that is a massive target, or all their conventional shipyards and naval yards. The existence of such a device probably also pushes the allied nations into a frenzy, so it would be interesting to see if they redirect war efforts away from Germany and the African theatre. Wondering also how the other Axis leaders (Mainly Hitler and his staff) would respond to Japan finding what essentially is a piece of alien technology.

It can go a million miles before refueling. Most likely, by that time, there isn't any enemy surface fleet left. If they are clever, they drop down for an hour or so every few days and take a sip of water to keep everything full. It by far outpaces any fleet, has a 300km radar and is invulnerable to any weapon they have. it can pretty much drop rocks on ships, or use bombs or simply shoot DOWN with 355mm guns - there is nothing in the US arsenal that could withstand this.

They can simply fly to any US habor and destroy everything there, or just fill the drydocks with tons of sand every few days. It can drop huge rocks on the panama canal. They can drop anything they like on the white house or pentagon.

Fun fact, if they can use pumps that way, they could simply fill their cargo hold with nothing but seawater and just drop that on a target.


http://www.youtube.com/watch?v=P5EuuHR9yiQ (Youtube linking seems broken)

Even a couple thousand tonnes, say 50k, of water will destroy pretty much everything in a large area, and the resulting flooding will mess up the rest. Pocket tsunami to drop in Detroit/LA/Denver/NY/wherever. Just start at the Pacific and work your way down, then along the Gulf coast and up the west coast. Obliterate any town with a certain radius of the coast. Fly back out, and pump more water, take off the moment you see something approach on radar, and deal with that beore you return to shedule.

The US will sue for peace in a matter of days or weeks, most likely before you have reached California (once they figured out what you are doing).

[Sky Captain]

It is actually fun to think how just 20 years after WW2 such vessel would be nothing more than huge fat target for swarm of nuclear missiles and high altitude bombers with nuclear bombs. Really shows how fast nukes changed everything.

[Sky Captain]

yes but probably the whole IJN would protect the sky fortress while it refuels, and a good portion of the IJA, fighter escort and stuff...
Plus no one said that the radar is turned off while refueling is underway...

#GoJAPAn #IJNVICTORY #BUSHIDOTOTALITARISM

No need for that. Just refuel in remote area out of reach of enemy bombers. By the time it will need to refuel there will be no enemy air force left to threaten it. Probably every one at the receiving end of such bomber from hell would ask for peace talks long before it needs to refuel.

One of the reasons why US military forces and industry were so effective during WW2 was no one had capability to mount serious attacks against US soil. This thing takes that huge adwantage away. Whole US is open to bombings, no city, factory or military base is safe.

[CetaMan]

Its pretty obvious the United States is screwed before it has to refuel, so unless its used horribly incompetently Japan essentially wins hands down.