Shop Forum More Submit  Join Login
Tyrfing-class SSVN Submersible Strike Carrier by Afterskies Tyrfing-class SSVN Submersible Strike Carrier by Afterskies
This is the final version of my Tyrfing-class.
I realized as I began imaging the top-down view that the original was far too snub-nosed and I had to lengthen the bow considerably to make it believable. This fortunately has the added benefit of extra space.

Hull Configuration: Soft Chine, Displacement, Tapered Low Chin Spoon Bow
-Surfaced: 72,000t (64 285 long tons)
-Submerged: 132,900t (118 660 long tons)
Length: 820ft (250 meters)
Width: 154ft (47 meters)
Draft: 63ft (Surfaced) (19.2 meters)
Height: 34ft (Surfaced) (10.3 meters)
Total Height: 97ft (29.5 meters)
Speed: 22 knots (Surfaced), 27knots (Submerged)
Test Depth: 250 meters
Crush Depth: 300 meters
Power Supply:
-(2) S6H1 310MW PWR
-(2) 5MW Emergency Diesel Generators
-(2) Battery Banks
---9 Day Propulsion Duration (Speeds < 5knots)
- 3 Day Full Propulsion
-45 Day Hotel-Load Duration
Propulsion: [list]
- (2) Asimov SEMP-9 Submarine Electric Propulsion Motor, 107,280 hp (80 MW)
- (4) Maneuvering Thrusters, Retractable
- (2) Deployable Outboard Motors, 2,000hp
Range: Limited by food supplies, Maintenance requirements
Sensors: [list]
- (IN PROGRESS) Surface Search Radar
- (IN PROGRESS) Air Search Radar
- (IN PROGRESS) Flight Control Radar
- (IN PROGRESS) Sonar Array
- 10 VLS Pods (4 ESSMs/3 Tomahawk missiles/3 Harpoon missiles, 12 Stinger missiles/ 1 UAV)
- 6 Torpedo Tubes (Bow)
- 90 Anti-Torpedo active countermeasures/explosives (45 PORT/STBD)
- 16 (8 PORT/STBD) Passive Countermeasures[/list]
Ship's Force: 140 Crewmen
Air Crew: 412 Airmen
Mission Crew: 64
Aircraft: 12-18
Air Platforms:
-  2 Parallel Ski-Ramp
-  2 Parallel 5-Wire Traps (In line w/ Ski Ramp)
- 2 Centerline In-Deck Elevators (One Fore, One Aft)
-  1 Designated VTOL Landing Site (Aft)
- 4 Aircraft Parking, Centerline

S6H1 Pressurized Water Reactor Plant
310 MW
S6H1 Stands for:
S: Submarine platform
6: Contractors sixth design generation
H: Halcyon Arms. Contracted Designer
1: First iteration of the present Reactor Design

The S6H1 is a Pressurized Water Reactor utilizing nuclear fission for the purpose of heat production to be used to create steam for usable work. The S6H1 is jointly designed and built by Halcyon Arms and Asimov Engineering. Core life is expected to be twenty years, depending on operations, maintenance, and modifications made. Utilized for only electrical power, the core may last for up to 60 years.  The reactor core is rated to 310 MW production capacity and utilizes highly enriched uranium as fuel. The Uranium is made into uranium oxide pellets which are then clad in zircaloy to make fuel-plates, which are stacked with gaps between them (for coolant to pass through), and made into assemblies, which are then assembled around a center channel design for the control rod to pass through, making a fuel assembly. This fuel assembly is immobile within the core.

A scaled up version of previous designs, the S6H1 is a two-loop reactor plant design, using highly pressurized and purified water as both coolant and moderator. The heated coolant passes through a boiler unit, heating it's water to produce steam. This water is then pumped back to the core by a reactor coolant pump, one per loop, where it passes around the reactor vessel, mixing with water from the other loop and then through a colander to ensure proper mixing of the coolant and filtration of debris, should any exist. From the colander the water passes up through the first-pass fuel channels for the initial heating, then out, around, and down the fuel assemblies to again pass upwards through the second-pass fuel channels, heating up the coolant further before ejecting it into the outlet region, where the coolant is sent back through towards the boiler units. The boilers provide steam for three turbine generators, one of which is used to power the reactor coolant pumps, and the other two powering the Common Electrical Distribution System, though they may provide power for the reactor coolant pumps.

Due to using water as a coolant/moderator, the reactor achieves natural stability. If the reactor experiences an up-power transient the coolant heats up further it will be less dense and moderate fewer neutrons, so more neutrons will escape the core, again lowering reactor power back to it's original state. The only process, therefore, which will change reactor power and maintain it steady-state at that new power is a change in steam-demand, save for massive introductions of poisons which drive the reactor out of it's power range, such a protective "Scram". Conversely, other factors can change temperature, namely the introduction of poisons, to include control rods. Control rods are used for reactor control as well as protection; in the event of a loss of power they will automatically scram (insert to the bottom of the core, shutting it down completely). This can also be done by the operator or by automatic action in the event of other casualties as well. Additional safety features include automatic filling of the reactor, should the core become depressurized and risk becoming uncovered, which would mean a lack of coolant and would allow for potential meltdown. With this, significant release of fission-product contamination external to the hull of the ship is guarded against.

The S6H1 is capable of operating up to 10% power without powering it's reactor coolant pumps; this natural circulation can be used for both decay heat removal and low power operations, making the reactor plant relatively quiet, but this natural circulation also provides for power transient-response and is not suitable for combat operations. As they are easy to cool without operator action or electrical power, the S6H1 is remarkably safe when shutdown. This also means that the reactor plant can perform a battery-only start-up, which is highly valuable for combat scenarios or a loss of all reactor plants simultaneously.

Radiation shielding is required and makes up the outside of the reactor compartment, which houses the reactor, boiler units, coolant loops, reactor coolant pumps, pressurizer, and filtration system. The shielding is made up of borated poly, water tanks, steel, and lead. It also has photovoltaic cells lining the inner wall to provide a trickle-flow of electricity to power the ship's battery and auxiliary reactor-plant batteries. With the reactor at power this trickle flow can be used to maintain supply of electricity to critical components. Entering this reactor compartment while the reactor is at power is considered to be deadly, but the layered shielding is so sufficient that personnel working in the propulsion plant will receive less radiation than those working on the weatherdecks of the vessel.

In the event of a loss of power, several emergency diesel generators can provide auxiliary power. This are primarily designed to support the reactor plant's automatic fill protection system, but they can also be aligned to the common electrical distribution system for propulsion power.
Add a Comment:
qgrg Featured By Owner Feb 1, 2019
The only issue I see is the low crush and test depth. Especially for such a large sub. Other than that, great design.
FatPigRidingABoar Featured By Owner Feb 10, 2017
I bet Yamamoto Isoroku Gensui Taishō would be proud.
Sensthepunmistress Featured By Owner Oct 22, 2015
Wow! a Silent Hunter Carrier!
saladin0604 Featured By Owner Mar 7, 2015
So THAT's the submersible carrier... I would really like to see this ship at the seas. 
Add a Comment:


Submitted on
March 6, 2015
Image Size
453 KB


10,169 (3 today)
110 (who?)