Insŏng-class destroyer

The Insŏng-class destroyers are the newest class of large guided missile destroyer built in Menghe. They are multi-mission warships capable of performing anti-air, anti-surface, and anti-submarine duties, and they reportedly have a secondary ballistic missile defense capability which will become operational when the YDG-69 anti-ballistic missile enters service in 2022. They are designed to serve as the flagships of larger surface formations, and carry generous onboard command facilities for this purpose. In some foreign navies, they are regarded as cruisers due to their size and command role; in the Menghean Navy, they are formally classified as "main-force escort ships" (Juryŏk Howiham).

Development

The Insŏng-class destroyers were developed as successors to the Haeju-class destroyers, which first entered service in 2006. Though the Haeju-class destroyers were generally well-liked, and their Onju subclass addressed many of the supposed shortcomings of the earlier ships, higher officers in the Menghean Navy were interested in a larger surface combatant which could more effectively protect a wider area. The successor design that subsequently emerged made improvements in each of the Haeju class's capability areas.

A mock-up of the new destroyer's superstructure was first spotted at a coastal missile testing range in Ryangnam Province in 2014. This structure was likely used to test the new ship's electronics equipment, which was still in development. Official state media at first suggested that the mock superstructure was intended for the Onju-class destroyer group, but based on clear differences in the superstructure and estimated measurements of the ship's size, independent analysts quickly concluded that it was part of a new class. This information was officially confirmed in May 2015.

The location of the test site stirred a great deal of discussion. The Menghean Navy had built test sites on land for decades, but usually in the blocked-off zone of the North Donghae Missile Range or at secret test areas in the northwest. The new test site, by contrast, was not only a short distance from Altagracia, but also clearly visible from the G76 expressway leading to the Juman Container Terminal and from civilian shipping lanes in Hwangsa Bay. Ostensibly, the Hwangsa Bay location was chosen to test the surface search radar's performance in an environment cluttered with civilian surface targets, but its proximity to Altagracia may have been a signal of strength to the Entente Cordiale states.

In 2017, the hull mockup fired surface-to-air missiles at a target drone over Hwangsa Bay, confirming that it was equipped not only with a full sensor suite but also with a fully operational vertical launch system. This suggested a further rationale for the chosen location: it allows the test site to provide air defense for Sunju, Tongju, Juman, and Dongchŏn, and guide long-range surface-to-air missiles into Altagracian airspace.

Design

Sensors and electronics

The main air search radar of the Insŏng-class destroyers is an AN/SPY-6(V)1 AESA system with four 37-module phased arrays. In addition to detecting air targets out to more than twice the range of the AN/SPY-1 arrays on the Haeju-class, these radars can conduct simultaneous air search, ballistic missile search, and cruise missile search scans. They are also believed to have a secondary active jamming capability.

Above the four AN/SPY-6 panels are four horizontal phased arrays optimized for surface search. Above these, atop the mast, is an NS50 radar for detecting low-level threats. Mounted 39 meters above the waterline, this system can detect a sea-skimming target flying at an altitude of 2 meters from a distance of 31 kilometers (17 nautical miles) and cue active-radar-homing missiles toward the threat. An electro-optical sensor on the rotating radar antenna improves detection and target identification against low-RCS missiles.

The shipboard electronic warfare suite is entirely new, and along with the AN/SPY-6 radar represents one of the class's major improvements. "Metturi" ESM/ECM arrays, on the corners of the superstructure, are optimized for the task of autonomously identifying and jamming nearby missiles. "Chasip" ESM/ECM arrays on the front and sides of the superstructure intercept enemy radio emissions, classify their source, and, with operator input, jam a sector or a wide area. The large phased arrays on either side of the superstructure are designated "Jadan," and are believed to be an especially high-powered jamming system. Nun-10 electro-optical sensors on the upper superstructure provide an additional mode of passive detection, while Hongmoja EO sensors on top of the bridge provide high-quality visual and infrared video feed to the combat information center. Four small receiver antennas around the upper sensor mast represent a possible COMINT system, but the Menghean Navy continues to offload most communications intercept and analysis duties to specialized intelligence ships.

The anti-submarine sensor suite is modeled after the suite carried by the Hasŏ-class cruisers, with a Ŭ-100D variable-depth sonar and a Ŭ-109 towed array. The hull sonar is a large low-frequency active-passive array, but lacks the extended side-scan panels of the Hasŏ class.

Armament

The Insŏng-class destroyers are fitted with 128 Mark 41 vertical launch cells in two 64-cell arrays, one forward and one aft. All cells are strike-length. A state news report in 2020 listed the following "typical loadout," though actual loadouts may vary based on the mission in question:

• 16 × HŎ-3 Ryongorŭm anti-submarine rocket
• 64 × YDG-64, quadpacked (16 cells)
• 64 × YDG-67, quadpacked (16 cells)
• 64 × YDG-68 long-range surface-to-air missile
• 16 × YDG-69 anti-ballistic missile (in development)

In addition to the vertical launch cells, the Insŏng-class destroyers have twelve long angled box launchers between the funnels, the same arrangement seen on the Sŏnsan-class frigates. These are believed to carry YDH-28 or YDH-90 anti-ship missiles, though because they use the same missile storage canisters as the vertical launch cells, a variety of loadouts may be possible.

Gun armament consists of a single HP-130/1 turret forward, the same as on the Haeju-class destroyers and Chunchŏn-class frigates. This gun can engage aerial as well as surface targets, and is loaded from a magazine below the waterline. As with many other Menghean warships, the Insŏng class do not carry any specialized autocannons for engaging light surface craft; instead, this role is left entirely to the deck gun and the two 23mm CIWS mounts.

In addition to the HŎ-3 anti-submarine rocket, the Insŏng-class destroyers are armed with two twin 350mm torpedo launchers for close-range defense. These are reloaded from the same magazine as the helicopters. They are located behind protective panels on either side of the aft VLS block.

Propulsion

The Insŏng-class destroyers are fitted with an all-electric propulsion scheme, with two 60,000-kW direct-drive electric motors driving two conventional propeller shafts. At full throttle, they can achieve speeds of over 35 knots. At low speeds, these electric motors also allow for very quiet operation, reducing the probability of passive detection by submarines and reducing noise interference with the ship's own sonar systems. The two motors are also staggered across two watertight bulkheads, and separated by a third.

The generators for the electric motors and the ship's systems are distributed around the ship, resulting in a high degree of redundancy in the event of a missile or torpedo hit. The four 3450-kWe Samsan 6EY33LW diesel generators are split between three watertight compartments spaced at wide intervals, and the ship can power its sensors, EW suite, and life-support systems on two generators alone. The four LM2500+ gas turbine generators are located not in the hull, but in the superstructure, 5.7 meters above the waterline and in two spaced compartments surrounded by fireproof bulkheads. This arrangement provides maximum protection against flooding damage, and also results in greatly increased noise insulation: for optimized anti-submarine operations, the ship can run one turbine to power the electric motors and onboard systems, keeping all diesel generators within the hull shut off. All generator units are mounted on vibration-damping rafts.

A single retractable propeller unit under the forward VLS group provides auxiliary thrust in the event that both electric motor rooms are flooded, and also allows easier docking and maneuvering in port.

Protection and countermeasures

For any anti-ship missiles that slip past the ship's large SAM arsenal, the Insŏng-class destroyers are fitted with two GBM-23/5 Bulkkot close-in weapon systems, one above the bridge and one above the helicopter hangar. Interestingly, both are baseline Bulkkot models, rather than the Dungji model with YDG-61 surface-to-air missiles or the Subisu CIWS used on the Haeju-class destroyers. Some analysts interpreted this armament choice as a judgment that the YDG-67 active radar homing missile was more accurate than the YDG-61, which by 2020 is nearly two decades old and had relatively modest performance even upon its introduction.

An official press release unveiled in August 2020 stated that the Menghean Navy is working on "unconventional close-in weapon system options" for later ships of the Insŏng class, including railguns, directed energy weapons, and a stacked charge volley gun. The same press release stated that the existing mounts are designed to allow easy installation of new close-in weapon systems in refits.

Additional defensive countermeasures consist of eight Ori radar decoy buoy ejectors, four Baram-2 chaff, flare, and decoy projectors, and two Manhwagyŏng-H torpedo countermeasure projectors. Crates of reloads for all decoy ejector types are mounted on the deck.

Aviation facilities

The quarterdeck of the Insŏng-class destroyers contains a landing area and hangar space for two helicopters. While nearly all previous postwar Menghean large surface combatants used some variant of the Gyundoan-Han GH-28 Ppulsoeori, the Insŏng-class can carry the larger GH-36 Mulsuri, a compound helicopter with a pusher propeller. Compared with the GH-28, this helicopter has a faster cruise speed, longer range, and higher sonobuoy capacity, allowing it to patrol a larger area.

Operational service

Chŏngdo's world tour

The second ship in the class, HJ-385 Chŏngdo, embarked on a special world tour shortly after being commissioned into the fleet. As part of this voyage, she circumnavigated the globe traveling east, conducting pre-scheduled courtesy calls at a number of friendly ports along the way. She was accompanied by the underway replenishment ship Yŏngjŏng, but otherwise traveled alone, without a larger battlegroup.

Chŏngdo's voyage started in her namesake port city of Chŏngdo, which she departed on 30 October 2020 three days, after her commissioning ceremony. From there, she made stops in Donggyŏng, Nakazara, the Aijuku Islands, Inishmore, Avallone, Sayamota, Inisheer, Guacara, Impor, Kopanes, Selkiö, Satamansuu, Lappo, Cartagena, Puerto Alegre, Ao Mangkon, and Quẚng Phẚ, Sunju, and Chanam, before finally docking in Gyŏngsan for a thorough post-voyage maintenance check. During most of these port visits, Chŏngdo was partially opened to the general public for tours of her deck and some non-sensitive areas. At Nakazara, Avalonne, and Selkiö, Dayashinese, Glasic, and Hallian naval officers were given exclusive guided tours of the ship's interior and allowed to inspect onboard electronic systems.

The voyage also included a number of naval exercises, particularly with Dayashina and Tír Glas. En route from Inishmore to Avalonne, she conducted a rendezvous with the guided missile cruiser Banbha. At several points on her voyage, she also conducted more aggressive exercises, sailing near Sieuxerrian naval bases in Scintillement and Anglian naval bases in the St. George Islands. On the long voyage from Impor to Kopanes, she also sailed close off the coast of Anglia and Lechernt, Sieuxerr, and Sylva, staying outside of EC territorial waters but claiming innocent passage through the EEZ. This was the first time an armed Menghean surface warship had passed through any of these areas, or for that matter through the Maw south of Inisheer. In addition to signaling Menghe's resolve, these maneuvers also provided an opportunity for the Chŏngdo to test her sensor suite against Entente aircraft, surface ships, and submarines.

Ships in the class

As of December 31, 2020, there were two Insŏng-class destroyers in service, five in fitting-out, and four more under construction in drydock, with a twelfth and final ship under contract. There are rumors of future orders under negotiation, but as of yet, the Menghean Navy has ordered twelve ships in total. They are built by the Gyŏngsan Songsu-do Shipyard and the Chŏndu New Naval Facility. Because the latter facility uses covered drydocks, ships built there are only partially built up when launched, with the rest of the mast lowered in place by heavy cranes during fitting-out.

The Insŏng-class destroyers, like their predecessors, are named for Menghean prefecture-level cities. Not coincidentally, a number of them share names with planned or operational battleships of the Greater Menghean Empire. Insŏng and Hwasŏng were the names given to two cancelled super-heavy battleships, and Chŏngdo and Sunju were the names of the two Chŏngdo-class battleships. With the announcement of Wŏnsan as the name of the last planned destroyer in 2020, some observers have noted that there are only a few remaining prefecture-level cities that do not yet have an active destroyer named for them, raising speculation that the Menghean Navy might alter its naming scheme at some point before mid-century.

Number	Name	Mengja	Builder	Laid Down	Launched	Commissioned
HJ-384	Insŏng	仁城	Gyŏngsan	2015 06 24	2017 05 11	2020 05 03
HJ-385	Chŏngdo	青島	Chŏndu	2015 09 07	2017 08 14	2020 10 27
HJ-386	Hyangchun	香春	Chŏndu	2016 12 10	2018 11 11	2021
HJ-387	Chanam	叉南	Gyŏngsan	2017 05 17	2019 02 20	2021
HJ-388	Chilsan	漆山	Chŏndu	2017 08 19	2019 05 31	2021
HJ-389	Jinyi	晉義	Gyŏngsan	2018 09 27	2020 08 17	2022
HJ-390	Sangha	商河	Chŏndu	2018 11 15	2020 08 20	2022
HJ-391	Sunchang	淳昌	Chŏndu	2019 06 04	2021	2023
HJ-392	Hwasŏng	華城	Gyŏngsan	2020 05 26	2022	2023
HJ-393	Taean	泰安	Chŏndu	2020 08 22	2022	2024
HJ-394	Gŭmchŏn	錦川	Gyŏngsan	2020 10 26	2022	2024
HJ-395	Wŏnsan	遠山	Gyŏngsan	2022	2024	2025

See also

• Yamazaki-class guided missile cruiser