Operation Sŭngsin

Operation Sŭngsin (Menghean: 승신 작전/勝神作戰, Sŭngsin Jakjŏn), named for the Menghean god of victory, was a military operation which the Menghean Navy conducted at the start of the Second Pan-Septentrion War. It referred to a period of high-tempo air, surface, sub-surface, and missile operations around the Strait of Portcullia between Innominada and Khalistan, targeting military assets of the Entente Cordiale, especially aircraft parked on land.

Menghe's main objective in Operation Sŭngsin was to seriously degrade the Entente's air and sea power in the Khalistan area, thereby allowing Menghean aircraft and surface ships to operate freely in the Strait of Portcullia and thus deny the strait to EC warships. The Menghean Navy's military doctrine heavily emphasized the need to inflict decisive damage on enemy forces during the first 24 hours of fighting, also known as the Opening Phase of Operations, and prewar Menghean force assessments concluded that the NF would need a 3-to-1 numerical advantage in combat aircraft around the strait in order to offset the capabilities of the EC's newly-upgraded Typhoon and Rafale fighters. The airfield strikes aimed to achieve this ratio by destroying Entente aircraft on the ground, where loss ratios would favor Menghe.

Measured in absolute terms, Operation Sŭngsin was a clear Menghean victory, as the EC suffered much heavier losses in ships, aircraft, and personnel. The Menghean Navy's general staff, however, considered it a failure: Menghean aircraft losses were higher than the operation's planners had anticipated, and EC aircraft losses were lower than anticipated. While it did tip the balance of forces around the strait in Menghe's favor, it did not fully eliminate the EC's ability to contest the airspace north of Khalistan, portending the indecisive outcome of the war.

Background

Balance of air forces

On the eve of the Second Pan-Septentrion War, the Entente Cordiale and the Namhae Front had a relatively even number of fourth-generation fighter aircraft on either side of the Strait of Portcullia, with the Namhae Front operating 408 aircraft and the Entente operating 362. These totals include only aircraft attached to operational fighter squadrons on either side of the strait, and not spares held in deep storage or reserve formations. They also include only aircraft flown by Menghean Naval Aviation. Menghean Army Aviation had several hundred more fighters in Innominada, as did the Republic of Innominada Air Force, but these formations were under the command of the Menghean Army and primarily concerned with operations over land. Therefore, they are excluded from the table below. The 20 Mirage 2000s operated by AeroBlades, a private military company based in Portcullia, are included in the table because Menghean planners anticipated that Sieuxerr would assume control of AeroBlades' forces at the outset of any major conflict with Menghe.

Balance of 4th Gen combat aircraft in the Strait of Portcullia Area, March 2022

Total Namhae Front combat aircraft	408	Total Entente combat aircraft	362
SR-8D Gŏmdoksuri	72	Typhoon	100
SR-8N Chowŏnsuri	36	Super Mirage 4000D	24
SR-8G Jŏndoksuri	12	Mirage 2000C	20
DS-9D/R Shin Biho	144	Valkyrie	36
DS-9G/N Biho (incl. Biho Gae)	144	Rafale B/C	182

These numbers do not reflect the differences in capability between the listed aircraft. By 2022, all EC fighter aircraft in the Strait of Portcullia area with the exception of AeroBlades's Mirages had been outfitted to fire the MBDA Meteor, an air-to-air missile with a range of over 200 kilometers. While Menghe's YGG-110 Chŏn Chang matched the Meteor in performance, it had only entered service in 2020 and was still in low-rate production. Only the SR-8D Gŏmdoksuri and DS-9D/R Shin Biho were able to fire it, and although the Strategic Logistics Agency of the Ministry of National Defense had prioritized YGG-110 deliveries to the Navy, top Naval planners anticipated that the stockpile of YGG-110s available at the start of April 2022 would only last for two days of high-tempo air-to-air combat. Furthermore, the Typhoon, Valkyrie, and Rafale all incorporated advanced composite materials to reduce their radar signatures, while only the SR-8D and DS-9D/R achieved similar levels of stealth.

Balance of surface forces

For most of 2021, the balance of surface forces around the Strait of Portcullia had generally favored the Namhae Front, except during periods when the Entente surged surface forces into the area. The Second Pan-Septentrion War, however, broke out during one of those periods, as the EC conducted a major exercise to support the reinforcement of Isla Diamante. On the morning of April 11th, the EC had four major groups of warships in the general area of Innominada:

• Task Force Acclamator, a Sieuxerrian amphibious battle group at sea east of Khalistan;
• Task Force Princess Royal, an Anglian carrier battle group at sea east of Khalistan;
• Task Force _____, an Anglian anti-submarine battle group docked in Fort St. Arthur; and
• Task Force Rhin, a Sieuxerrian amphibious battle group at sea west of the Strait of Portcullia.

All of these formations contributed to the battle in some way, either by sustaining damage or by firing at Menghean aircraft or missiles. They were supported by a small number of independent corvettes and patrol ships of the Khalistani Navy and Portcullian Navy.

Other Entente assets in the South Menghe Sea included Task Force Carnatica, led by Maracaibo's sole fixed-wing carrier and operating northeast of Sefrou; Task Force Auvernhe, a Sieuxerrian carrier battle group at sea west of Khalistan; Task Force ____, a Sylvan carrier battle group near Isla Diamante; and a Sylvan amphibious battle group overseeing Isla Diamante's reinforcement. The two Sylvan task forces were targeted in Operation Sondokki, also known as the Naval Battle of Isla Diamante, and Task Force Carnatica was sunk in Operation Chŏnman. Task Force Acclamator did not take part in any combat on the first day of operations.

Although the Menghean Navy operated a large number of surface ships, it relied primarily on land-based assets while operating in the vicinity of the Strait of Portcullia. CVBG Gukga Gyŏngje Gijŏk took part in Operation Chŏnman, supported by its independent surface screens, and the 2nd and 5th Anti-Submarine Battle Groups conducted patrol operations east of the strait and did not see combat. Only the following formations were committed to the operation:

• Independent Cruiser Chilsan
  • HJ-388 Chilsan (Insŏng-class destroyer)
• 2nd Destroyer Brigade
  • HJ-379 Pungsu (Haeju-class destroyer)
  • GY-224 Josu (Chŏndong-class destroyer)
  • GY-228 Dolpung (Chŏndong-class destroyer)
• 9th Destroyer Brigade
  • HJ-366 Dongchŏn (Haeju-class destroyer)
  • GY-227 Ho-u (Chŏndong-class destroyer)
  • GY-226 Ilchul (Chŏndong-class destroyer)

In preparation for the offensive, the 2nd and 9th Destroyer Brigades, normally structured as independent formations, were grouped together with the Chilsan into a single ad-hoc formation under the command of Rear Admiral Ho Gyŏng-sŏk. This seven-ship formation was effectively structured as a surface action group, centered on the large destroyer Chilsan rather than an aircraft carrier. Previously a Brigadier Admiral in command of an Escort Brigade, Ho Gyŏng-sŏk was specifically promoted to Rear Admiral in order to give him command authority over such a formation. His flagship Chilsan was also rushed into service in response to news of an EC military deployment: originally scheduled for delivery in late April, she was commissioned on March 27th, before the completion of some non-essential trials.

Menghean battle plan

In a series of classified studies conducted in 2015, the Menghean National Defense Advisory Agency (an organ of the MoND) reached sobering assessments about the relative effectiveness of the Menghean air force. In a series of simulated air-to-air engagements, Menghean DS-9G fighters armed with YGG-7 missiles suffered 3-to-1 losses in engagements with Entente Rafales when the latter were armed with Meteor AAMs. Due to their smaller radar signatures and longer-ranged AAMs, the simulated Entente fighters consistently outfought their Menghean opponents in beyond-visual-range combat, though the two planes performed equally in within-visual-range engagements. These studies expedited the development of the YGG-110 missile, the DS-9D Shin Biho, and the SR-8D Gŭmdoksuri, but they also pushed Menghean military planners to seek aggressive solutions to the perceived imbalance in air power between the two blocs.

Citing these studies, Menghean doctrinal planners estimated that after YGG-110 stockpiles were exhausted, but before Meteor stockpiles were exhausted, DS-9G/N fighters would suffer 3-to-1 losses in engagements with Typhoons, Valkyries, and Rafales. Therefore, these planners concluded, Menghe would need to achieve a 3-to-1 ratio in 4th-generation fighters in order to maintain air superiority over the strait. Any lower ratio would eventually shift the balance in the EC's favor.

Thus, the primary objective of Operation Sŭngsin was to inflict decisive losses on Entente land-based fighter aircraft in the first 24 hours of the war. If the Menghean Navy managed to destroy three-quarters of the EC's 4th-gen fighters adound the Strait of Portcullia in exchange for no more than one-quarter of its own, it would enjoy a 300-to-90 advantage in fighter aircraft, a 3-to-1 ratio which would remain stable in the following weeks of the conflict if the 3-to-1 loss ratio unfolded as expected. To achieve such a feat, Menghe would have to rely on submarine-launched missiles, land-launched missiles, surface ships, and the added initiative provided by a surprise attack in order to destroy Entente fighters on the ground.

The initial version of the Operation Sŭngsin plan called for four diesel-electric submarines to covertly approach Entente land targets on the eve of the war, then launch SY-56 Ho-u runway-cratering cruise missiles at H-hour, which would be 1030 hrs Menghean Standard Time. These missiles would crater the runways of the EC's major land bases, grounding all aircraft without giving sortie-ready fighters time to scramble. These same submarines would also fire long-range YŎ-53/19 torpedoes to engage Entente warships docked in major naval bases on the Khalistani coast. To disable the EC's surface-to-air missile defenses in Khalistan, a flight of SR-8G1s would release large numbers of WYGP-100 Saehorigi glide bombs, at which point individual DS-9 formations would approach at low level to engage short-range air defenses and CSNS guidance jammers, clearing the way for a follow-up strike with heavier guided bombs. In order to suppress Portcullia's longer-ranged MASURCA missiles, all of which were based at a stationary PAAMS site, Menghe would send Special Group Chilsan to Portcullia, where its ships would bombard the PAAMS site with rocket-assisted shells shortly after midnight on the 12th and then cruise southeast along the Portcullian coast, bombarding the airbases at Alexandriaville, Newcastle, and Dewsbury. A follow-up strike would then hit surviving targets across Portcullia.

At some point, this plan was revised, in light of the consideration that SY-56 missiles fired from the forward-deployed submarines would be shot down by land-launched surface-to-air missiles before reaching their targets. Instead, Menghe drew up a revised version of the plan, in which the NF would first compel the EC to scramble its ready fighters prematurely by conducting a feint attack with land-launched decoys supplemented by fighter aircraft. After repelling this attack, the surged EC fighters would have to land to refuel and rearm, leaving more of them trapped on the ground by cruise missile strikes. At this point, Menghe would fire a large number of land-attack cruise missiles across the strait, with the primary goal of overwhelming Entente missile defenses. The submarines would then launch their SY-56 cruise missiles afterward, exploiting gaps in missile and gun defenses created by the first cruise missile save.

Weather conditions

The Second Pan-Septentrion War began in the middle of April, which, in the Eastern Hemisphere, marked the shift of the inter-tropical convergence zone from Northern Meridia to Southern Hemithea. While the dry season was still ongoing across Southern Hemithea, with clear skies and firm ground, cloud cover over Northern Khalistan was nearing peak density. Throughout the entire duration of Operation Sŭngsin, all of Northern Khalistan, including the island of Portcullia, was experiencing overcast weather, with a dense cloud ceiling starting at 2,800 meters and additional clouds higher up.

This prevented the use of photographic reconnaissance satellites, high-altitude optical reconnaissance drones, and high-altitude laser designation equipment: any aircraft surveilling ground areas or designating targets for laser-guided munitions would have to drop below cloud cover, exposing them to short-range munitions. Low-level fighters would also be the only assets capable of performing post-strike battle damage assessment. It also prevented the use of Menghean TY-8N Sŭngri short-range ballistic missiles and TY-8H Anhae anti-ship ballistic missiles, both of which relied on electro-optical seekers to acquire their targets.

The attack

Torpedo attack on Fort St. Arthur

On April 11th, at 0830 hours local time, the Chŏngsangŏru-class diesel-electric missile submarines JY-964 Gangkkochigogi and JY-963 Julbenjari received the coded ELF radio signal announcing the start of offensive operations. Each submarine fired eight YŎ-53/19 long-range port strike torpedoes toward the docks at Port St. Arthur, with the submarines firing from launch positions 121 and 135 kilometers away, respectively. These torpedoes approached at a speed of 30 knots, slowing to 15 knots in the confines of the harbor for greater maneuverability. After firing their payload of long-range torpedoes, JY-964 and JY-963 immediately began loading standard sonar-guided torpedoes in order to engage any submarines or surface ships, and turned north to exit the area at a speed of 5 knots.

As the larger missile submarines retreated, two Pirami-class midget submarines--JH-1510 Junggogi and JH-1501 Songsari--began moving further south in order to lay mines outside Moradabad and Fort St. Arthur, respectively. An Anglian Protector UAV dispatched to patrol the north coast of Khalistan detected Junggogi at 1006 hrs local time, sinking her with an air-dropped torpedo. The same UAV detected Songsari five minutes later, again sinking her. Neither submarine would have had time to release its full payload of sea mines.

The first wave of YŎ-53/19 long-range torpedoes arrived in Fort St. Arthur at 1042 hours, catching Royal Navy sailors entirely by surprise. One struck the helicopter carrier ____ but failed to sink her outright. One destroyer and one frigate were split in two by torpedoes detonating under their keels. A second frigate was also hit, but her crew managed to confine the flooding to the aft machinery room, and one of the corvettes in the formation suffered serious flooding damage to her steering room after a torpedo impacted the pier aft of her stern. A fifth torpedo impacted an empty pier in the base, and the remaining two apparently drifted off course and did not find the harbor; witnesses reported only six underwater explosions.

The second wave of torpedoes, fired from a longer distance, arrived at 1058 hours local time. The helicopter carrier ____, which was already taking on water, sustained two more hits and began to flood much more rapidly. She capsized at 1102, killing many of the seamen who were fighting the existing damage and trapping a number of survivors inside the hull. The surviving two frigates were also hit, with one of them rapidly sinking in deep water and the other settling on the seabed after losing power to her pumps. The corvette ___, already damaged by the first wave and unable to leave her pier due to damaged rudders and propellers, was hit a second time, breaking in two. Three warships survived the torpedo attack: one damaged frigate, which had sustained flooding damage but still had a fully operational combat suite, and two corvettes, which were out at sea and had not been targeted. Task Force ____ had been effectively wiped out.

Previously working further afield, Entente maritime patrol aircraft over the strait began a concentrated search of the areas north of Moradabad, hoping to find the submarine which had launched the torpedo strike on Fort St. Arthur. JY-938 Chŏngsangŏri, tasked with launching SY-56 cruise missiles at the South Heart and Alexandriaville airbases, was detected by a P-8 patrol aircraft at 1148 hours and engaged, sinking before her commander could ascend to periscope depth or launch missiles.

First Entente counterattacks

Minutes after receiving news that the Menghean Navy had fired on Sylvan forces at Isla Diamante, eight ECB-1 bombers began taking off from Hell's Mouth Airbase in central Khalistan. Kept on high alert due to the risk of a Menghean pre-emptive strike, the ECB-1s were each loaded with 20 SCALP missiles, for a total of 160. After forming up and flying to standoff range, the bombers released their payloads at 0859 hours local time. These missiles impacted the Rosario naval base over the course of 1027 to 1030 hours local time, after YDG-64 SAM sites and short-range anti-aircraft guns shot down some but not all of the incoming missiles.

The submarine base in the southwest lost its on-site generator, command bunker, and one cruise missile magazine. One hit an empty SSK-sized tunnel, and two hit an empty SSGN-sized tunnel, caving in both. Another empty SSGN-sized tunnel was hit once, and though it did not cave in, it was ruled unsafe in a postwar inspection. The SSK-sized tunnel housing JY-962 Dolgorae sustained a single hit; the submarine was struck by falling rubble and severely damaged. The SSGN-sized tunnel housing JWY-945 Munmyŏng sustained three hits, which fully caved in the tunnel and completely buried the submarine.

Another group of cruise missiles continued on to Rosario's surface ship base, home to the 124th and 125th Fast Attack Craft squadrons. All docked FACs except KYD-174 Tran Omar were destroyed by direct impacts or missile debris. In addition, DChS-1622 Baekrabsu was destroyed in her drydock and DChS-1624 Jajuk was sunk at her pier. Two missile depots and one fuel tank were also destroyed, as was the command center of the 124th Fast Attack Craft Squadron.

More Menghean FACs were lost at around 1120 hours, when four Typhoon fighters engaged four Meng Dae-wŏn-class missile boats from the 124th Fast Attack Craft Squadron. All four were sunk by SPEAR 3 missiles, though one Typhoon was shot down by a land-launched YDG-67 missile.

Between 1125 and 1135 hours, a strike package of eight Sylvan Mirage 4000Ds, eight Sylvan Rafale fighters, and twelve Sieuxerrian Rafale fighters followed up with an attempted SEAD attack on Menghean SAM sites in the Rosario area, including the YDG-67 installation which had recently revealed itself by engaging the Typhoons. The YDG-67 site, however, far outranged the EC's ARMIGER anti-radiation missiles, and all Super Mirage 4000Ds were shot down, along with ten Sylvan Rafales. Menghe lost seven DS-9Ds, three from the 106th Light Fighter Squadron and four from the 116th Light Fighter Squadron. Tha Chang Airbase sustained only light damage, with one parked DS-9N destroyed in its hangar by a cruise missile.

Menghean cruise missile attack

While the Entente SEAD mission was ongoing, the four YDH-28 missile brigades in southern Innominada fired a total of 144 SY-28 cruise missiles at each airbase group in Khalistan and 240 missiles at the group of airbases in Portcullia, for a total of 672 cruise missiles fired. The launches began at 1130 hours, and were timed so that all cruise missiles launched would arrive in short succession, followed closely by SY-56 runway-cratering missiles. The three surviving Chŏngsangŏri-class submarines fired their missiles at 1208 hours local time, though unbeknownst to the other crews, Chŏngsangŏri herself had been sunk 20 minutes earlier.

The sight of cruise missile contacts appearing from the surface of the ocean alerted Entente patrol aircraft to the location of the Menghean diesel-electric missile subs. Anticipating this, the three submarines rose to periscope depth and extended their short-range air search radars to detect incoming aircraft. At 1212 hours, JY-963 Julbenjari surfaced, extended her YDG-61 launcher, and shot down a Protector UAV with one missile. Six minutes later, at 1218, she shot down an Anglian P-8. JY-964 Gangkkochigogi shot down a Protector UAV under similar circumstances at 1214. One minute after that, JY-961 Tobsangŏ shot down an incoming Sieuxerrian P-8 near Portcullia.

At 1219, an Anglian P-8 responding to the loss of a Protector UAV arrived at JY-964's position, where her copilot spotted the wake from the submarine's surfaced sail. Braving SAM fire like a Pan-Septentrion War bomber, the P-8 closed with the target. One missile overshot the P-8; another hit its starboard engine, which caught fire. On its remaining engine alone, the P-8 dropped a torpedo at the submarine and pulled away. Still surfaced and running slowly, JY-964 was hit by the torpedo before she could dive; her captain gave the order to abandon ship. JY-961 Tobsangŏ was engaged by a Sieuxerrian P-8 at 1224 hours, but both of her missiles missed, and she too was sunk by a torpedo impact.

The damage from the Menghean cruise missile strike was severe, but lighter than expected. Kaylan, Redhill, and the AeroBlades Primary Airbase were both thoroughly cratered, rendering them inoperable. The airbases at Cape Vale, Takata, and Newcastle also suffered extensive runway damage, but all had sections of runway which were long enough to land and recover Typhoons and Rafales. The airbases at South Heart and Alexandriaville suffered minor damage to their hangars, but their runways remained intact.

The original Menghean battle plan for Operation Sŭngsin called for a large wave of airstrikes which would begin immediately after the cruise missiles hit. At 1100 hours, however, the Menghean planning office received reports that the Entente's combat air patrol was still active: rather than landing to refuel after three hours as expected, the airborne Typhoons and Rafales had extended their patrols with the help of tankers, part of a deliberate EC effort to keep fighter aircraft off the ground at the outset of the conflict. In a bid to minimize air-to-air losses, Vice Admiral Yun Chang-su ordered his aircraft to delay the first wave, instead launching its escort group independently to engage EC AWACS and tankers. Menghean and Entente fighters skirmished over the course of 1220-1240 hours local time, with the two sides taking roughly equal losses: 14 DS-9Ds and Rs and two SR-8Ds, in exchange for 13 Typhoons, five Rafales, and three Super Mirages. Menghe also managed to shoot down a Sieuxerrian AWACS aircraft over Portcullia.

See also

• Operation Chŏnman