Pirami-class submarine

The Pirami class is a type of midget submarine designed in Menghe and built at the Eastern Submarine Yard in Anchŏn. A total of 12 have been built for the Menghean Navy, and the type has also been exported to Argentstan, Ummayah, and Azbekistan. With a relatively heavy armament of four 533mm torpedo tubes, but no special forces insertion capabilities, it is designed to raid ports, lay minefields, and sink coastal shipping, while leaving special forces missions to other midget submarine types.

Development

From the 1960s onward, the Democratic People's Republic of Menghe developed a number of midget submarine classes, most of which were assigned to the areas around Altagracia, Hanhae, and the Renkaku Islands.

Interest in a new midget submarine class returned in 2005, after relations with Innominada severely deteriorated as a result of the Ummayan Civil War. To deal with the new threat along its southwestern border, the Menghean Navy established a Southwestern Flotilla, which would specialize in coastal operations against Innominada. Part of its mission, shared with the South Sea Fleet, would be to attack Innominadan warships in port at the start of any war, inflicting attrition on Innominada's Eastern Fleet. As part of this mission, the Southwestern Flotilla would require more modern midget submarine classes, incorporating quieting and endurance lessons learned from the larger Bung'ŏ class.

Design work began in 2006, and work on the first boat began in 2009. All vessels in the class were built at the Eastern Submarine Yard in Anchŏn, which specializes in small and medium submarines and submersibles. The Menghean Navy ordered twelve units in total, and after the end of the Innominadan Crisis, it arranged for exports to Menghe's allies in the Namhae Front.

Design

The main armament of the Pirami class consists of four 533mm heavyweight torpedo tubes arranged in a 2-by-2 square. No reloads are carried, and torpedoes must be reloaded through the front of each tube while the submarine is drydocked. This also makes the torpedo launch process relatively quiet, as there is no need to clear each tube with compressed air after firing; water is left in them to compensate for the mass of the fired torpedo. Wire-guided torpedoes cannot be fired, as they would extend beyond the sonar and periscope detection range.

In place of a torpedo, each tube can be loaded with two tube-deployed mines. Additional mines can be mounted on top of the submarine and released while underwater.

The submarine is powered by a diesel-electric propulsion system. It has a range of 2,150 nautical miles (4,000 km) when snorkeling, or 215 nautical miles (400 km) on batteries. This is sufficient to travel from Menghe to Puerto Alegre and back with fuel left over for loitering and contingencies. It is also sufficient to travel from Ummayah to the Acheron Islands, or from Cartagena to Baumburg, on a similar round-trip mission, though most missions would cover shorter distances.

Compared with previous Menghean midget submarines, the Piramis incorporate a reasonably high level of quieting, with rafted machinery and a modern electric motor. They are the first Menghean submarine class to enter service with a pump-jet propulsor. On top of their small size, an anaechoic rubber coating reduces the submarines' active radar signature. In case of detection, they carry sixteen ejector tubes for Manhwagyŏng torpedo countermeasures, to distract lightweight torpedoes and mask the submarine's retreat. Pirami-class submarines off the coast of Innominada are painted in a mottled blue-and-green camouflage scheme to reduce the probability of visual detection from the air when submerged in shallow water; some units based near Altagracia have a brown color scheme to hide in the muddy Ŭm River Estuary.

Role

Unlike many other modern midget submarines, which have some special forces delivery capability, the Pirami class are purely designed around the anti-shipping role. Special forces delivery would be left to other midget submarine classes. The main missions of the Pirami-class revolve around the following tasks:

• Infiltrating enemy harbors to sink moored and anchored ships
• Loitering outside of ports and harbors to ambush ships as they enter and exit
• Laying mines at the entrances of ports and harbors, or on key coastal shipping routes
• Raiding coastal shipping between ports
• Providing a defensive screen against surface ships to protect amphibious landings

Initially the Menghean Navy planned to assign four Pirami-class submarines to Altagracia and eight to the Southwest area, with some of those in maintenance at any given time. After the Innominadan Crisis, Menghe moved four to Argentstan off the coast of Isla Diamante and four to the Republic of Innominada north of the Strait of Portcullia. From there, they would be in a position to attack the island of Portcullia and EC naval bases in Khalistan.