Chŏndong-class destroyer

Class overview
Builders:	Gyŏngsan Songsu-do Naval Yard Kimhae Naval Yard
Operators:	Menghe
Preceded by:	Nunbora-class destroyer
Succeeded by:	none
Built:	1982-1995
In commission:	1985-present
Completed:	14
Lost:	2
General characteristics (as built)
Type:	Destroyer
Displacement:	3,300 tons standard 4,540 tons full load
Length:	128.7 m overall 119.1 m at waterline
Beam:	13.1 m at waterline
Draught:	4.87 m to keel
Propulsion:	steam turbine propulsion 4 high-pressure boilers 75,000 shp
Speed:	34 knots
Range:	4,000 nautical miles (7,400 km) at 18 knots
Complement:	20 officers 223 enlisted crew
Sensors and processing systems:	2 × HR-210 air-search radar HR-280 surface-search radar Ŭ-12 hull sonar
Electronic warfare & decoys:	2 × JJ-5 ECM antenna
Armament:	1 × HP-130/2 Type 82 dual 130mm turret 8 × YDH-23 anti-ship missile 2 × 8 YDG-36 surface-to-air missile (24 reloads) 4 × GBM-30/6 CIWS 2 × RBU-6000 depth charge launcher 2 × 3 450mm torpedo tube 120 mines

The Chŏndong-class destroyers were a group of fourteen warships built in Menghe during the 1980s and early 1990s. They are designed around anti-surface warfare, carrying a heavy main battery of eight YDH-23 anti-ship missiles and a HP-130/2 Type 82 twin 130mm main gun. Their anti-aircraft armament, however, is limited to short-range point defense, and their anti-submarine armament is also relatively weak. Ships of the class have no helicopter facilities, and are entirely reliant on land-based aircraft or aircraft from nearby warships for targeting.

Owing to their small size and lack of helicopter facilities, the Chŏndong class are sometimes described as frigates. A few foreign intelligence services have remarked that in terms of role, they more closely resemble large corvettes. The Menghean Navy officially classifies them as "missile destroyers" (Yudotan Guchugham), in contrast to the contemporary Yobu-class destroyers, which are classified as "escort ships" (Howiham).

Development

The Chŏndong class are direct successors to the Nunbora-class destroyers, which likewise carried heavy AShM and gun armament but had poor anti-air and anti-submarine capability. Menghean naval planners envisioned sending them out in groups of four, led by a Yobu-class destroyer, to launch coordinated missile strikes against enemy carrier battle groups.

Design

Three-view blueprint of the Plan 272 design. During construction, the centerline crane was removed and the aft funnel was shortened, along with other minor changes.

The design was primarily the work of Jin Gi-tae, the chief naval architect at the Naval Design Institute. Rejecting earlier proposals that had called for a large and flexible destroyer, Jin insisted on a compact, efficient warship built around a clear mission. This choice was a function of Menghe's military needs at the time: facing two opponents with greater industrial capacity, Jin Gi-tae believed that the only way to balance in national defense was to create a warship that could be produced in large numbers and easily maintained. This meant restricting features and capabilities superfluous to the core mission's needs.

The design went through several iterations, each time decreasing in tonnage. Even smaller versions were considered, sacrificing, for example, the aft surface-to-air missile mount. Other problems concerned the powerplant. Jin Gi-tae originally hoped to install gas turbine propulsion in a CODOG arrangement, for a high maximum speed and fuel-efficient cruising. Technological constraints, however, limited Menghe to the use of a steam turbine plant, which in turn was derived from that on the Yobu class.

Construction

The final iteration of the design, designated Plan 272, was approved for mass production by the MoND, with the first hull laid down in March 1982. Construction was carried out under conditions of considerable secrecy, with the final fitting-out conducted in the city of Wihae rather than Gyŏngsan where the drydocks were located. For this reason, Dayashinese intelligence officials originally labeled the destroyer as the Wihae class.

Construction work was complicated by Menghe's first nuclear test in November 1984, which officially placed Menghe in violation of the STAPNA agreement. Faced with an embargo with its few remaining trading partners, including Polvokia, Menghe encountered delays in securing key components for the hulls still under construction. Economic dislocation under Ryŏ Ho-jun's ill-conceived reforms also disrupted supply chains, even as the Navy fought to limit interference in shipyard operations.

At the same time, the worsening geopolitical situation led the Menghean Navy to launch the Second Emergency Shipbuilding Program, stepping up new orders of Chŏndong-class warships to confront the increasing risk of an enemy attack. The Gyŏngsan 2 drydock, originally intended for cruisers and large destroyers, was appropriated for Chŏndong construction, and the Kimhae Naval Yard took on additional orders. Some documents from the period suggest that the DPRM intended to build a total of 25 Chŏndong-class warships, more than any postwar destroyer class.

After the Decembrist Revolution, the Second Emergency Shipbuilding Program was slowed down, and the military budget was decreased. The eight ships which remained in various states of construction in 1988 were completed on a reduced schedule, and three additional ships were laid down after 1989, all of them at Gyŏngsan. Later construction included careful inspections for faulty parts installed during rushed building, and both Chŏndong and Swaejŏn were drydocked in 1989-1990 to identify and replace faulty parts and welds. The basic design, however, was not modified during this stage, though there was some discussion of building the last two ships with helicopter facilities.

Description (as built)

Main armament

GY-216 Chŏndong as she appeared shortly after commissioning.

The YDH-23JG supersonic anti-ship missile, top left, with wings folded and boosters fitted.

As built, the Chŏndong-class destroyers carried a powerful forward-facing battery of eight YDH-23JG "Yusŏng" anti-ship missiles. A surface-launched derivative of the Letnian KSR-5, the YDH-23 follows a quasi-ballistic trajectory toward the target, climbing to an altitude of 25 to 30 kilometers before descending at a terminal speed of Mach 4. While it has a maximum range of 280 kilometers when air-launched (500 kilometers for improved variants), the surface-launched variant has a range of only 200 kilometers due to the loss of fuel while ascending through denser low-altitude air.

Readying these missiles for launch could take over two minutes, a longer time than on Letnian warships, with an additional 15 seconds between ready status and launch. The launchers themselves could only fire missiles at 10-second intervals, but this could be reduced to 5 by alternating between port and starboard batteries. Total time to fire a full salvo was in theory just 40 seconds, but could be longer with a less prepared crew. The missiles could only engage targets 30 degrees to either side of the bow, requiring the ship to face toward its target during the launch phase.

Other armament

Gun armament consists of a single HP-130/2 Type 82 twin 130mm gun mount. This weapon system was designed specifically for the Chŏndong class, and boasts improved traverse performance and a higher rate of fire than the SM-2-1 mount on the Nunbora class. It is capable of engaging ships, land targets, aircraft, and incoming anti-ship missiles, using contact, timed, or proximity fuses. Special guided rounds and submunition rounds were also later introduced.

Close-range gun armament consists of four AK-630 CIWS guns, two on each side. The forward pair are slightly further outboard than the aft pair, allowing both mounts to fire directly aft. Combined with the superstructure layout, this arrangement also creates a blind spot in CIWS coverage at 15 degrees to either side of the ship's prow. Air defense over this arc depends entirely on the main gun and surface-to-air missiles.

The surface-to-air missile armament, like the gun mount, was designed specifically for the Chŏndong class. Originally, it consisted of two launch modules for the YDG-36 surface-to-air missile. Each module consists of an eight-box launch unit, plus 24 reload missiles stored below deck. Each mount can cover a 270-degree arc, resulting in full 360-degree coverage with overlapping coverage to either side. Each mount carries a combination of radar-guided and infrared-homing missiles, for greater redundancy against countermeasures, jamming, and poor atmospheric conditions, and each of the four radar illumination antennas can guide two missiles toward one target at maximum. Post-launch trials and operational service revealed that the YDG-36 had very poor accuracy and reliability, and during refits these mounts were replaced with the Subisu combined-gun-and-missile CIWS.

Anti-submarine armament consists of two three-tube 450mm torpedo launchers, one on either side of the forward funnel. Sources disagree on whether reloads are usually carried. Further aft are two RBU-6000 depth charge rocket projectors, which can also throw sonar decoys to distract incoming homing torpedoes. Because the ships lack any kind of variable depth sonar, they cannot detect submarines below the thermocline except at very short ranges, and their anti-submarine weapons are purely intended for self-defense.

Sensors and electronics

The first group of Chŏndong-class destroyers (Chŏndong through Pado) were fitted with two HR-210 3D air search radars, one on each mast. The two-radar layout, also present on the Nunboras, was intended to provide a measure of redundancy in the event that one radar is damaged in battle or taken down for maintenance. On Hongsu onward, these are replaced by HR-270 3D search radars, a licensed version of the MR-710 Fregat ("Top Plate") radar on Letnian ships. The new radar type was also fitted to the early-production hulls during their mid-life refits.

Atop the bridge is a more impressive HR-280 surface search radar, located inside a large radio-transparent dome. This J-band system exploits atmospheric ducting to detect surface targets beyond the regular radar horizon, and has both active and passive modes. Its long range allows the Chŏndong class to generate firing solutions for the YDH-23 anti-ship missile even without support from aerial reconnaissance aircraft, though such aircraft would normally be part of a coordinated strike operation.

The ships' only sonar equipment is a single "Plamina-S" antenna in a bulge under the bow. The ships carry no variable-depth or towed-array sonar, and cannot embark helicopters for area search operations.

A modest electronic warfare suite with two active jamming antennas provides defense against incoming anti-ship missiles. There are also two amidships chaff-and-smoke projectors to interfere in missile guidance systems; these were upgraded during refits as well.

Refits and subclasses

GY-222 Hongsu, the first ship completed to the modified configuration, as she appeared in 1990.

GY-221 Bŏmram as she appeared during the Battle of the Aqaba Sea, showing the "Chŏndong Ia" refit.

GY-224 Josu in 2007, with Subisu CIWS in place of the YDG-36 launchers.

GY-227 Ho-u, one of three ships rebuilt with Mk 41 VLS cells and Dungji CIWS. Until the early 2010s, her VLS cells could only fire the YDG-7G surface-to-air missile.

The first six ships in the class, GY-216 Chŏndong through GY-221 Bŏmram, were built to the original blueprints, with two HR-210 air search radar sets. This layout was intended to confer some degree of redundancy, in the event that one air search radar set was damaged in battle or taken down for maintenance.

After the Decembrist Revolution, Menghe was able to purchase newer MR-710 Fregat ("Top Plate") radar sets under the Menghean designation HR-270. This system was mounted on GY-222 Hongsu and the ships commissioned after her. Because the MR-710 was more reliable--and more expensive--these ships only received one air search radar each, mounted on an effectively identical mast structure. The aft mast was replaced by a simpler tripod design with a platform for a signal lamp operator. Foreign navies referred to these ships as the Chŏndong II subclass, though this designation does not appear in any Menghean sources; curiously, the Menghean Navy did not designate the Hongsu group as an independent subclass.

In 2000, the Menghean Navy began work on GY-216's mid-life refit and overhaul. This included the following changes:

• The YDH-23 launch boxes were replaced by launch tubes for the YDH-25, Menghe's license-produced version of the P-270 Moskit. Though it has a shorter range, a lower speed, and a smaller warhead, the YDH-25 can follow a sea skimming trajectory all the way to the target, making it harder to detect and intercept. Later Menghean variants of the YDH-25 would also boast improved performance, including the ability to perform pseudo-random evasive maneuvers on the final approach.
• The forward HR-210 radar was replaced by a HR-270 (MR-710 Fregat) radar, and the aft MR-210 radar was replaced by a signal lamp, though the sturdier aft mast was retained, carrying forward an aesthetic difference from the Chŏndong-II group.
• Chaff and smoke projectors were added, and the older parachute-jammer launch tubes were removed.
• The original JJ-5/6 ESM/ECM suite was replaced by the JJ-7/8 ESM/ECM suite. Though already somewhat dated for the 2000s, the JJ-7/8 system was more powerful and incorporated a number of new features, such as the ability to detect and classify anti-ship missiles by their radar emissions and automatically assign JJ-7 jammers to each threat.
• The fire-control radars for the 30mm CIWS mounts were upgraded.
• The ships were fitted with solid cargo CONREP kingposts just aft of the forward funnel, and liquid CONREP receptacles port and starboard of the aft missile magazine.

The original steam turbine powerplant was not replaced by a diesel powerplant, as some proposals had suggested, but the boilers and turbines were inspected and thoroughly refurbished. The YDG-36 launch boxes were also retained, despite growing concerns about the system's obsolescence, based on a judgment that newer surface-to-air missile systems were not yet in service. Engineers reportedly considered fitting the ships with SATCOM domes as well, but turned down the idea based on a judgment that there was too little space available. Foreign sources refer to the five ships refitted this way as the Chŏndong Ia group.

Following the Battle of the Aqaba Sea, part of the Ummayan Civil War, the Menghean Navy altered its refit plans for the Chŏndong class. GY-222 Hongsu and GY-224 through GY-229 were rebuilt to a modified standard: Subisu CIWS mounts replaced the YDG-36 launchers. This refit was long in the making, as the Subisu CIWS's below-deck space was specifically tailored to have the same dimensions as the YDH-36 magazine to allow precisely this kind of drop-in replacement, yet the losses of GY-221 Bŏmram and GY-223 Noesŏng expedited the design process. The new Subisu CIWS mounts obviated the need for the AK-630 CIWS mounts, so these were removed, with their deck space replaced by Baram-2 countermeasure launchers and their magazine space replaced by expanded crew accommodations. They also obviated the need for YDG-36 illumination radars: the forward pair on the sides of the bridge were removed along with their supporting braces and electronics boxes, and the aft pair on the aft mast were replaced by SATCOM domes. Foreign sources refer to this configuration as Chŏndong IIa, though Menghean sources generally refer to them as the "Hongsu refit group."

The Subisu CIWS drop-in upgrade was deemed urgent enough that GY-216 through GY-221 were all sent back into refits in 2006 to have their YDG-36 launchers replaced. For GY-221 Bŏmram, this came just two years after she completed her original pre-Subisu mid-life refit. The first batch of ships emerged from this refit with identical capabilities to the Hongsu refit group; they differ only in the appearance of their aft masts. Foreign sources refer to this configuration as Chŏndong Ib.

GY-227 Ho-u, GY-228 Dolpung, and GY-229 Pokpung underwent refits one year after the rest of the ships in the class, in 2007-2008. They were completed to a more advanced configuration: the YDG-36 magazines were replaced by self-defense-length Mk 41 VLS modules, with non-deck-penetrating GBM-23/5Y Dungji CIWS mounts fore and aft of the VLS cells. The resulting 32 self-defense-length VLS cells were originally meant to be loaded with individual YDG-7G surface-to-air missiles, but the introduction of the quadpacked YDG-7N and YDG-64 allowed for a major expansion in magazine capacity, with some cells instead loaded with vertically launched YDH-26 anti-ship missiles. As on the previous refits, the forward AK-630 mounts were replaced by Baram-2 chaff and smoke launchers, but the aft AK-630 mounts were instead replaced by STIR 1.2 guidance radars atop deckhouses containing control stations and electronics. The YDG-36 illuminators on the sides of the bridge were also replaced by STIR 1.2 illuminators. Other Hongsu-group refits were also carried forward to these three ships, including the new electronic warfare suite, the underway replenishment gear, and the MR-710 Fregat radar. Foreign sources refer to this configuration as Chŏndong III, and some Menghean sources refer to them as the Ho-u subclass.

Over the course of the 2010s, all of Menghe's surviving Chŏndongs received minor upgrades and improvements, though none of these merited new class designations in Menghean or foreign literature. By the outbreak of the Second Pan-Septentrion War in 2022, additional improvements to the Chŏndongs included the following:

• Yŏjŏm FSO datalinks, fitted to the aft mast.
• Unidentified SIGINT gear, also fitted to the aft mast.
• Radar decoy buoy projectors, installed in two launchers with two reloads aft of the second funnel on GY-216 through GY-226 and in four launchers with no reloads on GY-227 through GY-229.
• On the Ho-u group, software upgrades to accept the YDG-7N, YDG-64, YDH-26, and SY-26 missiles.

The manual signal lamps were also removed at some point after the Innominadan Crisis. On some ships, the signal lamp on the aft platform was replaced by a civilian satellite television dome.

Service

During the Ummayan Civil War, Chŏndong-class destroyers played a prominent role in the Battle of the Aqaba Sea.

In the fighting that followed, two Chŏndong-class destroyers in the task force were lost. The Bŏmram succumbed to air-launched anti-ship missiles on the afternoon of the 14th, while the Noesŏng was damaged in the aerial attack yet remained afloat. Despite damage to the rear superstructure, she was able to retreat under its own power, but began experiencing engine problems overnight. During the early dawn hours of March 15th, Noesŏng was struck by a torpedo from an Anglian submarine, and split in half directly beneath the funnel. As all ships in the formation were maintaining radio silence, and the captain had no time to send a distress signal, the ship's loss went unnoticed among the ships further ahead until 1103 hours when a patrol helicopter sent from the Migi failed to locate her.

Later on the 15th, a Dayashinese destroyer arrived to pick up the survivors. This move was a major step in cementing Menghe-Dayashinese relations. A monument to the Noesŏng was built in the city of Yanggang in 2008, and the captain of the Dayashinese ship was invited to the unveiling ceremony, where he was greeted by the survivors.

The wreck of the Noesŏng today lies within Ummayah's exclusive economic zone, but as a signal of gratitude, the Ummayan government in 2010 allowed Menghean salvage vessels to conduct dives over the ship's hull. The helm, recovered intact from the bridge, was brought to the surface and transported to the monument at Yanggang, after serving as a two-year temporary display in Gyŏngsan. The recovery team also claimed to have brought up the remains of Captain Ho Tae-su, cremating them for use at a Sŏngindan in his hometown of Hwasŏng. Some skeptics have questioned the official explanation of the recovery, charging that the description of Captain Ho "still standing at the helm" was unlikely and that the ashes used were not his.

Ships in the class

Ships in the Chŏndong class are named after weather systems, in keeping with ship naming conventions in the Menghean People's Navy. This again contrasts them with the Yobu-class destroyers (officially escort ships), which were named after Menghean prefectures, and the Pyŏng'ans and their successors, which were named after Menghean cities.

Name	Meaning	Builder	Laid down	Launched	Commissioned	Status
Chŏndong	Thunderclap	Gyŏngsan	1982 Mar 25	1983 Dec 23	1985 Jul 06	--
Donghan	Bitter cold	Gyŏngsan	1983 Feb 12	1984 Sep 24	1986 Apr 06	--
Swaejŏn	Chain lightning	Gyŏngsan	1983 Apr 06	1985 Apr 18	1987 Nov 05	--
Pado	Wave	Gyŏngsan	1984 Jan 04	1985 Aug 18	1988 Oct 31	--
Pungrang	Stormy waves	Kimhae	1984 Mar 28	1985 Oct 21	1988 Apr 22	--
Bŏmram	Deluge	Gyŏngsan	1984 Sep 31	1986 May 02	1989 Oct 17	Sunk by Anglian aircraft on 17 Mar 2005
Hongsu	Flood	Gyŏngsan	1985 Apr 29	1987 Jul 01	1990 Jun 30	--
Noesŏng	Thunder	Gyŏngsan	1985 Aug 25	1988 Mar 04	1990 Dec 18	Sunk by Anglian submarine on 18 Mar 2005
Josu	Tide	Kimhae	1985 Oct 27	1987 Sep 03	1990 Feb 10	--
Ubak	Hailstorm	Gyŏngsan	1986 May 09	1988 Jul 18	1992 Jan 25	--
Ilchul	Sunrise	Gyŏngsan	1987 Jul 12	1990 Feb 13	1991 Oct 14	--
Ho-u	Downpour	Gyŏngsan	1990 Feb 21	1991 Nov 12	1993 Jun 29	--
Dolpung	Squall	Gyŏngsan	1991 Jan 13	1992 Aug 27	1994 Mar 09	--
Taepung	Typhoon	Gyŏngsan	1992 Sep 02	1994 Jun 28	1995 Nov 01	--