Battle of Hwangsa Bay

Battle of Hwangsa Bay
Part of the Pan-Septentrion War
Date 17 September 1945 Location Hwangsa Bay, Menghe Result Allied victory
Belligerents
Organized States New Tyran	Greater Menghean Empire
Commanders and leaders
	Admiral Ri Gyŏng-su
Strength
	Total: -- combat ships 1 battleship 2 heavy cruisers 3 light cruisers 12 destroyers
Casualties and losses
	1 battleship 2 light cruisers 4 destroyers 1 heavy cruiser damaged

The Battle of Hwangsa Bay, sometimes called the Battle of Hoang Sa Bay or the Battle of Hwangsaman, was a naval battle fought between Allied carrier aircraft and Menghean warships on 17 September 1945. It was the last major naval battle involving forces of the Greater Menghean Empire, not counting isolated sinkings of escort ships by Allied submarines and aircraft in the two months that followed. Due to inclement weather the following day, the Allies were not able to sink the entire Menghean task force, as they had initially hoped; they did, however, inflict severe losses, and the battle is widely considered an Allied victory.

The battle began when the remains of the Menghean Second Fleet, previously holed up in Sunju, sortied to the southeast in an attempt to slip past the Allied blockade of the area and relocate to Chŏlsŏng. As this would allow them to subsequently move to Menghe's eastern coast, which was much better-defended, the Allies mounted an attack on the fleeing ships with carrier-based aircraft. In the hours that followed, the battleship Anchŏn was sunk, along with two light cruisers and three destroyers. The following day, the destroyer Judŏk ran aground on a shoal, and the heavy cruiser Godongsan was hit by two torpedoes from a Columbian submarine, suffering severe damage which left her confined to Chŏlsŏng for the remainder of the war.

Background

Menghean retreats

By the middle of 1944, the Imperial Menghean Navy had lost any hopes of parity in the war at sea. Owing to its smaller economy, which was already spiraling into hyperinflation, Menghe was unable to commission new ships as fast as old ones were being lost, let alone match the pace of construction in the Organized States. Ostland's surrender earlier in the same year also allowed Tyran, Sylva, and the OSC to transfer their Casaterran fleets to the Eastern theatre, further skewing the balance of forces. Allied victories in Meridia also cut off Menghe's main supply of oil, and the Army received high priority in the rationing of remaining stockpiles. Faced with all of these problems, in July 1944 Navy High Command issued an order effectively confining all major warships to port, on the basis that victories at sea were unlikely and the main threat came from the western land invasion.

While the vast bulk of the IMN, including the First and Third Fleets, withdrew to the east coast, which faced the East Menghe Sea and was reasonably safe from attack, the Second Fleet and a few patrol and auxiliary units withdrew to Sunju in the south. There, Admiral Pak Sŏng-chŏl hoped to use them as a deterrent against any Allied amphibious attack on the Ŭm River Delta area. At the end of 1944, his force consisted of two battleships, one fleet carrier, three heavy cruisers, three light cruisers, and about two dozen destroyers, a small fraction of the Columbian naval presence in the South Menghe Sea but a large enough force to interfere in any Allied plans near the Chŏllo coast.

The Second Fleet's transfer plan

In February 1945, the Navy's upper leadership decided that the Second Fleet's carrier, Hyŏngsangang, should transfer to Gyŏngsan, a safer location. The carrier departed on the 15th with the heavy cruiser Yaksusan and three destroyers as her escort force. Only four days after her departure, and while within sight of the Menghean coast, the Hyŏngsangang was torpedoed by a Columbian submarine. Most of her crew survived by swimming to shore, but the carrier was lost, striking a major blow to the morale of the already isolated Second Fleet.

As the year progressed, Columbian and Maverican forces began a rapid drive across the Chŏllo plain, threatening Sunju and Insŏng. Both land-based and carrier-based aircraft made repeated attacks on the warships docked in port, but they failed to inflict serious damage, as the city's formidable flak defenses made low-altitude approaches too dangerous. More worrying for Menghean commanders was the steady advance of the front lines, and the possibility that the Second Fleet could be captured in port. By this time, Allied strategic planners had also abandoned the idea of a separate naval invasion on Menghe's southern coast, so the Second Fleet had little to gain from its use as a deterrent.

Supreme Admiral Pak Sŏng-chŏl, the highest commander of Menghean naval forces, finally issued a retreat order in September 1945, commanding the entire Second Fleet to depart Sunju as a group. They would first transfer to Chŏlsŏng to take on additional fuel and supplies - according to some sources, Sunju did not have enough stockpiled heavy oil to support a direct voyage to the East Menghe Sea - then proceed to Gyŏngsan in the southwest. From that new base, nestled in the cliffs and islands of the southeast, they could regroup with the First and Third Fleets to threaten powerful counterattacks against Allied naval forces south of Dayashina. The objective and plotted course were unsettlingly similar to those issued to the Hyŏngsangang and her escorts seven months before, especially as Columbian and Tyrannian naval forces had grown increasingly bold in their operations near Menghe's coast, but by this point any further delays in Sunju could leave the fleet trapped until the city's eventual fall. Admiral Ri Gyŏng-su, commander of the Second Fleet, agreed with his analysis, and began making preparations for a withdrawal.

Allied interception plan

Unbeknownst to Menghe's military planners, a Tyrannian intelligence team had long ago broken the Imperial Menghean Navy's new code, which was modeled closely after the Ostlandian Enigma code. As soon as they received news of the Second Fleet's transfer plan, Columbian and Tyrannian naval officers began discussing ways to intercept the Menghean force. Direct interception with a surface fleet was ruled out, as the Second Fleet still had two battleships and two formidable heavy cruisers, and it would be within range of land-based strike aircraft. Columbian planners also feared that if Menghean aerial scouts spotted their battleship formation, they could inform the departing fleet and lead it to change its schedule.

Therefore, the Allies settled on an interception using carrier-based aircraft. Three attack waves would strike on September 17th, the day of the departure, focusing on the battleships. The following day, Allied carrier aircraft would mop up the remaining ships in follow-up waves. The first wave would be timed to strike when the fleet was already far enough from the city, so that the second wave would still have time to engage if the ships turned around and returned to Sunju. Altogether, three carriers - two Columbian, one Tyrannian - were assigned to the operation.

Course of the battle

Sortie operation

Admiral Ri's ships left their docks at 0630 hours on September 17th, commencing the escape operation. One formation, consisting of shallow-draft vessels, proceeded up the Ŭngang river, where it would take the inland route to Dongchŏn and bypass Allied forces at sea. The remaining vessels, accompanied by an escort force of destroyers, would break to the south, proceeding along the western edge of the bay as close to shore as the depth of the water would allow. The Menghean commanders knew that Allied reconnaissance planes were in the air, so their departure would not be kept secret for long, but they were still unaware that the Allies had cracked their naval communications code and expected that they could break out of the bay before the first strike aircraft arrived.

Almost immediately, the Menghean force ran into problems. Shortly after leaving her pier, the battleship Haeju began reporting engine problems, which soon escalated to a fire in one of her boiler rooms. Inadequate maintenance was the most likely culprit - in spite of accumulated battle damage and routine wear and tear, the Haeju did not receive a comprehensive engine refit in 1943 - though some sources speculate that a crew member may have sabotaged the engine room in order to keep the ship home from a potential suicide mission. Whatever the cause, the captain of the Haeju reported at 0648 that his ship was unfit to embark on a long voyage and needed to return to port immediately. Unwilling to risk a further loss of power on the long voyage eastward, which could slow down the rest of his formation or force him to leave a battleship behind, Ri ordered the Haeju to return to her dock and remain in Sunju.

Further misfortune followed when the heavy cruiser Godongsan briefly ran aground while maneuvering to make room for the Haeju. The Ŭmgang River had not been dredged adequately in years, and silt from upstream had accumulated in sandbars and shallows in the estuary. With the help of harbor tugs, the Godongsan was eventually able to free itself from the mud, but its delay held up the rest of the fleet. Only at 0815 did the deep-draft formation resume its course into the harbor. Concerned about the buildup of silt and mud elsewhere in the harbor, Rear Admiral Ri also decided to follow an alternate course out to sea, carrying the ships further from shore.

First Allied strike wave

The first wave of Allied aircraft made contact with the Menghean formation at 0925, while it was still in the center of the bay. Allied pilots were initially confused to see only one battleship, the Anchŏn, in the Menghean fleet, and dispatched one formation of fighters and torpedo bombers to the north, on the possibility that the Haeju was lingering behind. Dive-bombers in the southern formation scored two hits on the light cruiser Hyangyang, igniting stored 20mm and 37mm AA gun ammunition and starting a fire on the quarterdeck. As her crew attempted to control the damage, the Hyangyang broke to port to make way for a destroyer moving behind her. The battleship Anchŏn suffered three bomb hits, but none penetrated her armor deck.

The northern group of Allied planes did not find the Haeju, which by now was back at its dock in the Ŭmgang River, but they did encounter a squadron of Imperial Menghean Army fighters dispatched to provide air cover for the fleet. Operating on a different radio channel from the Menghean ships, the Army pilots assumed they had encountered the main Allied strike force and proceeded to engage it.

The southern squadron of torpedo bombers now made its attack on the Anchŏn, concentrating on the battleship's starboard side in the hopes of creating uneven flooding inside the ship. They came under withering fire from the nearby heavy cruisers Godongsan and Hanmaesan, but nevertheless managed to score four hits on the Anchŏn. One of these caused flooding in one of the ship's boiler rooms, forcing her captain to reduce speed as the damage control teams worked to contain the flooding.

The Hyangyang suffered two more dive-bombing hits, this time on her foredeck, one of them penetrating deep into the hull and punching a hole below the waterline from within. As the ship's bow began to dip, her captain broke away from the formation and sailed east at full speed, eventually running aground in the shallow mud 800 meters from shore. There, he hoped to continue putting up anti-aircraft fire from an unsinkable position, but the ship's stern was still in deep water. Seeing that the cruiser was immobilized, a lingering group of Allied dive-bomber pilots broke away from the main force and attacked it, one of them scoring a hit which detonated the stored depth charges under the quarterdeck. The Hyangyang's stern and most of her aft AA deck slipped below the surface as she settled entirely onto the seabed, leaving only her bridge, funnels, forward turrets, and parts of her foredeck above the waterline.

See also

• Battle of the Portcullia Strait
• Battle of Altagracia (1935)