Amphisbaena

Amphisbaena-class battleship

“Half ahe… that way.”

– Capt. Olavi Corel, first captain of Amphisbaena

Displacement: 125,000 long tons

Length: 330 m (at waterline: 316 m)
Beam: 84 m (at waterline: 48 m)
Draft: 12.1 m

Propulsion:

4 x Empire Nucleonics, ICC 64 MW “Fat Salamander” fission reactors
8 x Blackstone Industries, ICC steam turbines and reduction plant
In-house magnetohydrodynamic “inchworm” drive system

Speed: 42 knots (non-sustainable emergency power: 48 knots)
Range: Unlimited; 12 year refueling interval

Complement:

1,672 officers and men
Thinking Machines, ICC “Admiral Aliniv” Command Optimization Thinker

Sensors:

Artifice Armaments, ICC, ASR-24/3 air search radar
Artifice Armaments, ICC, SSR-36 surface search radar
Artifice Shadow Works X-449 imaging lidar
Hydrodyne Technologies, ICC, “Long Ear” sonar suite
Tactical interweave uplink

Armament (Primary):

6 x Artifice Armaments, ICC 22″ “Big Howlin’ Bitch” railgun
6 x triple Artifice Armaments, ICC, 16″ “Little Sister” railgun

Armament (Secondary):

24 x Artifice Armaments, ICC 9″ “Poniard” conventional gun
36 x Firefly Aerospace, ICC “Waterline” anti-ship seeking missile
36 x Firefly Aerospace, ICC “Gentle Touch” target-finding missile
8 x Eye-in-the-Flame Arms, ICC “Pesticide” automated threat protection system

Armor:

Citadel: 24″ layered C-allotrope/alloy composite; equiv. 53″ steel
Main turrets: 18″ layered C-allotrope/alloy composite; equiv. 39″ steel
Elsewhere: 12″ layered C-allotrope/alloy composite; equiv. 26″ steel

Aircraft carried:

16 x Stonesmight Automata, ICC “Tattletale” scout drones
16 x Stonesmight Automata, ICC “Fleshharrower” attack drones

The four Amphisbaena-class battleships were the last fast battleships laid down by the Imperial Navy (note: the “wet” navy of the era, not its space successor), and participated in a number of military actions including the last battles of the Consolidation to take place on Eliéra proper. They are widely considered to represent the pinnacle of the naval architect’s art, and the furthest development of the “wet” battleship as a class.

The design of the Amphisbaena-class, in keeping with the mandate the IN inherited from the Alatian Navy’s Weapons Development Board, was to produce a vessel that would utterly outclass any opponent against which it was set. Thus, the class carries six 22″ railguns – of a model designed to be scaled down for naval use, rather than used as is – in addition to its six triple 16″ railgun turrets and conventional armaments. This same approach led to the inclusion of the eight “Pesticide” automated threat protection systems, capable, once activated, of automatically reducing anything not tagged as friendly approaching within a mile of Amphisbaena, above or below the water, into chaff and charnel.

The final development of this approach was Amphisbaena‘s magnetohydrodynamic “inchworm” drive. While the primary characteristic of this type of drive is its quietness, and thus lower sonar profile, in the case of Amphisbaena, it was selected because its lack of the issues associated with high-performance propellers, coupled with an otherwise oversized power plant, enables Amphisbaena to reach the otherwise unprecedented – for a ship of its displacement – cruising speed of 42 knots.

It also has the advantage of functioning equally well in either direction, and this – combined with the ability to divert water to side outlets at both bow and stern – gave Amphisbaena unparalleled abilities not only to change heading 180° without turning at all, but also to decelerate, to turn in its own length, and to keep station – making it an incredibly stable gun platform.

It is also to this drive that Amphisbaena owes its entirely symmetrical hull profile and superstructure, since the designers felt no need to inflict the notion of a preferred direction on a ship which otherwise would have lacked one. Despite the quotation above, officers and men serving on Amphisbaena-class ships rarely had difficulty telling the bow of the moment from the stern when the ship was under way, but it is nonetheless true that a red-blue color gradient was added to the bridge paintwork after Amphisbaena‘s sea trials to make end from end clear when moored or hove to.

Notable Replies

  1. …damn it.

    I now have to get out my copy of GURPS Vehicle Builder and build Siren Yamoto, because why not?

    (Siren Yamoto is what happens when you say “okay, take the TL-6 warship and build it exactly the same mass with TL-10 technology.” Nine 23cm very long-barreled railguns are going to make anybody’s day unhappy. And AA guns that are actually worth something!)

  2. A Battleship can survive shells piercing their belt armor, a projectile penetrating the turret face results in a dramatic loss of firepower and possibly an explosion, less likely with railguns mind but losing half your firepower to a single shot early in the battle could easily change the course of the engagement. The point being that the turrets ought to be the most armored part of the ship. Further my suspicion is that a conventional 22" gun might be able to pierce the main battery turrets but fail on the belt for at least a little bit.

    Lastly super/hyper sonic chaff above the waterline can still deal considerable damage to the target ship even if the main warhead is dust on the wind. Which is to say even if your CIWS is lethally effective you should still intercept weapons over there rather than over here. Which in the context of naval weapons means extended range surface to air missiles because the horizon limits the maximum range of laser weapons even if they are arbitrarily powerful, radar and therefore guns reach a bit further.

    Technically the range is limited by consumables carried onboard or about 4.5 million miles.
    You also need about twice as much power to go 48 knots verses 42

  3. Avatar for avatar avatar says:

    On the armor, it was mainly the explosion risk I was thinking of; while it does impair firepower, a hit on a railgun turret doesn’t get you a magazine explosion because there’s nothing to explode. The not-immediately-required shells for the conventional guns and especially all those lovely missiles, that’s the kind of thing they want to keep safe behind the extra-heavy citadel armor because a hit on those magazines is uncomfortably likely to be a ship-killer.

    On the chaff issue - the CIWS is intended to clean up anything that gets through the screen, and a battleship’s not supposed to operate without screen. Which is to say, there are plenty of those anti-air missiles, but they’re on their equivalent of Aegis cruisers.

    I listed the range the same way you tend to see it for CVNs: unlimited in the sense of “you will never run into this issue”. :upside_down_face:

    I’ll double-check my envelope for the speed, but there is a lot more power available in that mode; “emergency power” is intended to cut off all other power-intensive systems on the ship (railguns, for a start) and dump all of the resulting surplus into the MHD. (The limiter on how long you can get away with that being when the superconducting coils in the MHD quench and vaporize themselves because you’ve spent too long playing chicken with the critical field/current.)

  4. Avatar for avatar avatar says:

    Ooh, that’s an interesting-looking piece of software.

    /me downloads

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