NationStates Jolt Archive

New silent and deadly diesel submarine lurks seas...

Castilla y Belmonte
12-12-2007, 20:58
Diesel Attack Submarine Type A

The Type A, or ‘Tipo A’, diesel attack submarine (SSK) is designed primarily to fit within the Castillian Armada’s requirements for a next-generation coastal defense submerged platform. These requirements include the reduction of detection as much as possible, maximization of time under water through the use of the latest in air independent propulsion (AIP), maximization of lethality for a low volume submerged vessel and the minimization of price. In other words, the Armada wants a lethal, state-of-the-art submarine without breaking current price tags on the international market. In conjunction with these requirements, Sisnaval is looking at maximizing export potential of the Type A submarine to fleets with a need for littoral defense. In regards to production for the Armada, Sisnaval has been contracted to produce thirty units in a first-batch and another thirty in a second batch. Ultimately, the Armada is looking forward to having enough diesel submarines to be able to deploy fifty at any one time, which means that the Armada will ultimately require at least one hundred and fifty submarines. Whether all of these will be Type As is currently unknown. It’s understood that Sisnaval is also planning to release a cheaper diesel submarine without air independent propulsion called the Type B – it has been reported that these will cost less than half the value of the Type A! However, it seems as the Type B will be an export option as the Armada has not shown interest in the designs to date.

Why the Type A? Why diesel-electric?
Castilla’s principle reason for choosing a diesel-electric submarine over a nuclear submarine is due to a number of important reasons. First, using a diesel submarine allows shrinking the design of the vessel for coastal defense. Currently, the Armada’s priorities do not include force projection, although there have been certain recent procurements – ten Triumph class aircraft carriers from Beaufort Naval Industries (BNI) – which may make it seem as if Castilla is putting importance in that area. Therefore, the ability to stay underwater until supplies run out is not necessarily important. A diesel-electric submarine using air independent propulsion can remain under water long enough to be a threat to any surface group. As an example, the Type A using its hydrogen fuel cell AIP system can remain under water for over two weeks! With this ability to submerge for long periods of time new diesel-electric submarines, like the Type A, can perform ambushes and hit-and-run attacks on enemy shipping. The principle drawback is the ability to attack at long-ranges from friendly coastline, like a nuclear submarine (especially given the long distances between nations and regions), but for a submarine designed for regional and national defense long-range isn’t a priority.

Second, diesel-electric submarines are markedly cheaper and lighter than their nuclear brethren. In the Type A’s case, the submarine goes for $475 million which is considerably cheaper than a larger, nuclear submarine. The Type A weighs 1,870 tons and is physically small, although it’s a tad larger than some other existing diesel-electrics since the Armada has specified a minimal weapon’s load for the design’s lethality. However, this is much smaller than the 7,000+ ton nuclear submarines currently in service around the world. Third, the Type A is especially stealthy. The boat has adopted a waterjet – seen on some of the more recent nuclear attack submarines – instead of the classical screw to reduce noise produced during movement. Furthermore, the water waste produced by the fuel-cell AIP system is spread along the length of the hull of the submarine to reduce the submarine's signature, while said hull is constructed out of anti-magnetic steel. Finally, when operating on electric power the noise produced during movement by the fuel-cell powered batteries is almost none.

It’s important to note that SSKs like the Type A are perfectly compatible in a fleet made-up predominately by SSNs (nuclear attack submarines). Given that theoretically the SSNs in any given navy were procured to offer that navy the ability to strike at an enemy at any given range and in any given location in the world’s large oceans and seas the SSN remains a power-projection tool – the ability to project fear into an enemy’s surface fleet at thousands of nautical miles off any nation’s shore. The SSK remains a tool that now may be superior to SSNs for coastal defense. Consequently, the two serve two different roles and purchasing one doesn’t mean that the other is suddenly worthless. A nuclear navy can operate diesel submarines.

There are various diesel-electric designs available on the export market, but the Type A has several advantages. First of all, the fuel-cell system is superior to other air-independent propulsion systems including the Sterling cycle engine and either the closed circuit diesel or the closed circuit turbine. To give an idea, Sterlings and closed circuit diesels operate with about 30% efficiency, while the turbine operates with a maximum of 25% efficiency – fuel cells operate with 70% efficiency. While the rest use indirect energy conversion, the fuel cell system directly converts energy and it has a markedly lower water consumption rate (.4 kg/kW). The quietness of the battery technology makes the Type A perfect for clandestine special operations, as well. True, this technology is not exclusively Castillian and may be adopted by other submarines on the market. However, Sisnaval guarantees the availability of spare parts and armaments for its submarines and also guarantees the availability of evolutionary technologies. In other words, instead of having to buy a new submarine to gain new technology Sisnavantia guarantees the ability to upgrade the Type A. Consequently, the life of a Type A can be considered longer than many others through the use of upgrades and improvements. A Type A will be able to compete against other designs for the next thirty years, or more.

In regards to sensor systems, the Type A is at the top of the spectrum. The submarine includes land navigation technology which allows it to perform closer to a nation’s coastline. The advantages are numerous, and it includes the ability for the submarine to hide using the nation’s coastal terrain (such as fjords) without the fear of having an accident or running aground. In that sense, the Type A can also operate in extremely shallow water. The submarine also has plenty of long-range sensors, including SONAR and RADAR, for long-range armaments and includes a number of devices to protect it from enemy torpedoes and helicopters. Against enemy sensors, as already said, the Type A has a number of features which make it incredibly stealthy – including a low radar signature when the submarine is sailing along the surface.

Origins of the name
Prior to the appearance of Sisnaval and the Type A, Castilla’s submarine fleet was composed of foreign diesel designs. The first submarine – truly a submersible, rather than a submarine – was procured in 1911 and between 1911 and 1914 Castilla saw six introduced into service, named A.1 through A.6 (the series was given the title of Class A). These were noisy, small, diesel-electrics which were used for coastal defense and to potentially harass Spizanian and Franberrian shipping. Six Class B submarines replaced the Class A starting in 1924 and these were far more advanced submarines, although still on the ‘cheap side’ given the kingdom’s lack of money (not to mention that at that time the kingdom was more worried about purchasing armaments more relevant to putting down rebellions). Between 1944 and 1947 four Class C diesel-electrics replaced the six Class Bs and these have remained in service until the appearance of the Type A. Given that neither Class of submarines were indigenously designed, the Armada has decided to rename the classification system for submarines and start again at Type A – Sisnaval sells the submarine with this title, although the designation can change from country to country.

However, as opposed to the Class A, Class B and Class C the designation of a new letter doesn’t necessarily mean that it is better than the last. For example, Sisnaval’s Type B is smaller and less advanced than the Type A, but offers a cheaper solution and can sail in much more shallow waters (such as rivers).

Type A procurement
Full rights to production are not sold, however a nation can purchase limited rights to production which simply means that Sisnaval gives the right to produce any given amount of submarines, specified by the contract signed by all relevant parties, to a specific naval defense yard in the client’s nation. Given the limited production capabilities of Sisnaval this might be preferred by some customers – especially those with large orders in mind. In regards to the cost, not all submarines will cost $475 million a piece. Bulk orders, understandably, will decrease cost by a relatively large margin. In regards to submarine construction, Sisnaval is currently offering the reduction of total price in exchange for the selling of naval defense companies relevant to submarine design to Sisnaval. Sisnaval is looking forward to being one of the leading submarine naval yards in the world.

Manufacturer: Sisnaval
Displacement: 1,870 tons submerged, 1,580 tons surfaced
Dimensions: 64m (length) x 6.7m (wide)
Hull Construction: Anti-magnetic steel
- Eight fuel-cell modules producing 48kW each, for a total of 384kW of power.
- Three diesel engines.
Velocity (Surfaced): 13 knots
Velocity (Submerged): 21 knots
Maximum Depth: 300m
Range (Surface @ knots): 7,000nm
Range (Submerged): 370nm
Periscope: A single Indra-Begón search mast and a single optronic mast.
- 6x 533mm torpedo tubes for submarine launched anti-ship missiles and heavy anti-ship torpedoes. Torpedoes are reloaded through the tubes, so no hatches are required. The submarine holds fourteen torpedoes.
- or 44 mines
Countermeasures: 2x AOS
Sensor Equipment:
- Cylindrical bow SONAR array.
- Flank array.
- Mine avoidance array.
- Land navigation array.
- Intercept array.
- Active array.
- Distributed array
- Towed array.
- Surface RADAR array.
Communications: Satellite communications, multi-frequency buoyant antennas and a slow broadband transmission. The submarine includes a small unmanned communications submergible for surface communications while the submarine is submerged.
Crew Compliment: 31
Cost Per Unit: $475 million

Castilla y Belmonte: 60