NationStates Jolt Archive


Secret IC: PIW develops countermeasures submarine

Sarzonia
29-09-2005, 05:38
Background: In an effort to address the unique threats presented by crawler mines placed on the ocean bottom and other assorted submerged threats, the Portland Iron Works set about to design a submarine to deal directly with the threats posed by such defences. Among the design specifications: A submarine armed with so-called underwater CIWS and including minehunting and sweeping technologies. The result of this planning and research is the Argonaut class countermeasures submarine.

Armament: To ensure the Argonaut is optimised for its defensive role in protecting surface and submerged threats, it has been designed with eight 35 mm supercavitating guns broadside to serve as a last-ditch defence against torpedoes. In addition, a new counter torpedo, designed to deploy upon detection of an enemy surface or submerged warship's firing of a torpedo, has been developed. This new 240 mm torpedo, the Epee, has been designed with a majority of its weight being made up of propulsion and guidance software, including GPS and targetting softwares with a small warhead to take out torpedoes. It is not designed to serve as an effective weapon against a surface or submerged warship, particularly with the emphasis on armour in many of today's warships, but it can serve as an anti-torpedo torpedo similar to AAA defenses. To serve as defence against larger torpedoes and against smaller escort vessels, the Argonaut also is armed with six 324 mm torpedo tubes.

Electronics: The Argonaut's hallmark is as a countermeasures submarine, and as a result, this is where the design sets itself apart from other submersibles. To counter assorted mines that threaten Sarzonian or allied threats, the Argonaut features the SLQ-53 mine countermeasures deep sweep system, AN/SQQ-32 minehunting sonar, and an AN/SLQ-48 mine neutralisation system. Similar to the old Osprey-class minehunters, the Argonaut uses a remotely controlled underwater vehicle to neutralise mines. Instead of some of the weapons outlay normally utilised by a patrol submarine, the Argonaut also includes two remotely controlled crab-shaped drones to detonate crawler mines before they can damage the fleet's vessels.

Protection: With the Argonaut's role as an escort and countermeasures submarine rather than a front line warship, emphasis has been placed on maximum stealth to allow the Argonaut to be a virtually "silent partner" for any fleet that employs it. To facilitate this stealth, the Argonaut has been covered with anaechoic tiles to reduce noise emissions and noise returned by active sonar. As a Sarzonian design, secondary emphasis has also been placed on survivability; thus, the Argonaut employs a double hull with an outer hull made of amorphous steel, a substance three times stronger than normal steel and non magnetic. The inner hull is made of a composite of titanium, vanadium and aluminum. The two hulls are separated by absorbant foam.

Propulsion: Great debate has centerd on whether to give the Argonaut a pressurised water reactor to allow it to remain submerged for several weeks at a time or a diesel electric engine to reduce noise and infared signatures emitted from a nuclear reactor. Ultimately, the PIW decided the initial run of the Argonaut would be powered by a Magnetohydrodynamic drive to ensure maximum stealth qualities. The drive, commonly referred to as a caterpillar drive, is virtually silent, making the Argonaut very difficult to detect with modern sensor systems.

Argonaut-class escort/countermeasures submarine
Length: 91 m; Beam: 11 m; Height: 12 m
Displacement: 3,100 tonnes full
Armament: 4 x 324 mm TT; 8 x 35 mm supercavitating guns (underwater CIWS); armament also includes 240 mm Epee anti-torpedo torpedoes.
Complement: 50
Propulsion: One Magnetohydrodynamic drive (3,500 shp), one 400 hp auxiliary prop motor. Speed: 12 knots surfaced; 15 knots submerged.
Electronics: SLQ-53 mine countermeasures deep sweep system, AN/SQQ-32 minehunting sonar, AN/SLQ-48 mine neutralisation system.
Countermeasures: AN/SLQ-25A Nixie; AN/SLR-24 Towed Array Subsystem Torpedo Countermeasures System
Cost: $750 million
Running Cost: $25 million per annum.