Donghae-class battleship
| File:BB Donghae.png Donghae shortly after her commissioning
| |
| Class overview | |
|---|---|
| Name: | Donghae-class |
| Operators: | Menghe |
| Succeeded by: | Chŏlsŏng-class battleship |
| Built: | 1908-1916 |
| In service: | 1911-1923 |
| Planned: | 2 |
| Completed: | 2 |
| Retired: | 2 |
| General characteristics | |
| Type: | dreadnought battleship |
| Displacement: |
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| Length: |
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| Beam: | 25.4 m |
| Draught: |
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| Propulsion: |
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| Speed: | 18.5 knots |
| Range: | 3,500 nm (16,700 km) at 10 knots |
| Complement: | 855 |
| Armament: |
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The Donghae-class battleship Menghean: 동해급 전함 / 東海級戰艦 was a class of two dreadnought battleships operated by the Federal Republic of Menghe during the early 20th century. They were the first class of dreadnought operated by the Menghean Navy. Because Menghe's shipbuilding industry was still developing at the time, both ships were built in New Tyran, an agreement which resulted in considerable delays during the construction of the Namhae.
Background
The concept for the Donghae-class emerged in response to the development of Septentrion's first "Dreadnought"-type battleships. Unlike their contemporaries, these vessels featured steam turbine propulsion in place of triple-expansion engines, and a unified main battery of six twin 12-inch guns in armored mounts. These features made them significantly more capable than previous designs, which were subsequently termed "pre-dreadnoughts." This revolution in naval design touched off a naval arms race as Septentrion's great powers raced to build their own dreadnought battleships.
Although Menghe was still a minor power at the time, its leaders soon expressed concern that the dreadnought revolution would once again leave Menghe at a technological disadvantage in naval combat. High Admiral Bak Myŏng-yong, who had witnessed Menghe's humiliating defeat to the Sylvan Navy and the loss of Altagracia, urgently demanded that Menghe obtain its own dreadnought battleship class in order to keep pace with the arms race.
Yet at the time, Menghe was still a very poor country rushing to close the gap with the world's industrialized powers. While the Kimhae Naval Yard in Donggyŏng had built armored cruisers and central battery ships in the past, its engineers doubted their ability to produce a state-of-the-art dreadnought warship. Instead, they began searching for foreign contractors, submitting requests to shipyards in Dayashina, Tol Galen, New Tyran, and the Organized States of Columbia. Of these, New Tyran provided the most favorable contract, and the first ship's keel was laid down in 1908.
Work on the ships proceeded on schedule until 1909, when the War of the Sylvan Succession broke out. Initially, New Tyran continued work on the Donghae and Namhae under the terms of the contract, in 1910 the Tyrannian builders suspended work on the still-drydocked Namhae in order to direct resources toward the war effort. Frustrated with continuing delays and fearful that the Royal Navy would press the ship into emergency service once completed, the Menghean Navy sent a crew to New Tyran in October 1910 to sail the Donghae back to Menghe for the remainder of its fitting-out. During this voyage, the crew suspended an enormous Menghean flag from the rigging between the foremast and mizzen-mast in order to avoid being mistaken for a Tyrannian vessel and attacked by hostile submarines.
The rest of the Donghae's fitting-out, including the mounting of her secondary battery and quick-firing guns, took place at the Kimhae Naval Yard. The ship was commissioned in the spring of 1911, where she led defensive patrols as the flagship of the First Battleship Squadron.
Throughout the war, the Namhae remained under construction on its slipway, though Tyrannian engineers never went so far as to salvage scrap steel from the hull. As the war reached its end, construction resumed, and the Namhae was delivered for fitting-out in 1915. By the time of its commissioning the following year, it was already obsolete.
Design
Armament
The Donghae-class dreadnoughts' main battery consisted of twelve 12-inch, 45-caliber breech-loading guns mounted in six armored turrets. These are Tyrannian-designed Mark X guns, the same type carried on New Tyran's other battleships of the period. In a layout common at the time, the gun turrets were arranged in a hexagonal shape, with one each at the bow and stern and two on each side. As a result, only four gun turrets could be brought to bear over a single broadside, though at least two could be aimed at any target.
The secondary battery consisted of twelve 6-inch Mark VIII guns in semi-casemate mounts, with the shielded gun able to traverse within an open gap in the hull side. Originally, the Tyrannian designers planned to arm the class with a tertiary battery of 12-pdr/18cwt quick-firing guns, but during the war they re-directed their production of QF guns to ship refits, and the Donghae was delivered without secondary armament. Upon arrival in Menghe, it was fitted with Menghean-built 7.5cm quick-firing guns, themselves based on an Ostlandian design.
In an effort to minimize weight and cost, both the secondary and tertiary gun mounts fired through hull openings close to the waterline. This meant that at high speeds or in heavy seas, these mounts were easily swamped by water, making them largely ineffective. The forward and aft quick-firing guns were especially prone to water ingestion, and in 1917 these guns were removed and their openings permanently sealed with steel plates.
Like other early Dreadnought designs, the Donghae-class also had a torpedo armament, in this case six 18-inch tubes below the waterline. One was fired through the bow, underneath the ram, and two more were placed on each broadside, with the sixth fired through the stern. All were fixed in place, and could only be aimed by steering the ship. A total of twenty torpedoes, four for each tube, were carried inside the ship.
Armor
The Donghae-class dreadnought's main armor belt was 12 inches (305 millimeters) thick, and curved inward inside the ship at its ends to form internal bulkheads forward and aft of the main gun turrets. The upper belt and front and end belts were both 102 millimeters thick, and a 1-inch protected deck was installed below the forward belt to limit damage from flooding. The central portion of the ship, including the magazines, engines, and boilers, was protected by a 3-inch armored deck.
Additional protection on the main battery consisted of a 10-inch plate on the front of each turret, 4-inch plates on the turret sides, top, and rear, and a 12-inch barbette extending down from the turret base to the magazines.
As built, all Donghae-class battleships also carried torpedo nets to protect them from light torpedo craft while at anchor. In 1921, there were plans to remove the torpedo nets and replace them with anti-torpedo bulges, which would provide protection while underway, though in the end it was deemed more efficient to simply scrap the Donghae-class and build new battleships instead.
Propulsion
Originally, the Menghean Navy's design requirements called for steam turbine propulsion, but the government forced them to downgrade to a triple-expansion engine in order to reduce costs. This left the ship with a maximum speed of 18.5 knots, about two knots slower than most contemporary dreadnought designs. The Donghae-class also had a relatively short operational range, 3,500 nautical miles when sailing at 10 knots. These constraints partly reflected the Menghean Navy's defensive expectation that it would fight close to friendly ports in a direct confrontation with an enemy fleet.
Service
Upon commissioning in 1911, the battleship Donghae was assigned as the lead ship of the 1st Battleship Division and, by extension, the flagship of the East Sea Fleet. The Namhae was originally intended as the flagship of the South Sea Fleet, but upon its delivery it was moved to the same Division as the Donghae. Both ships remained in the weaker East Sea Fleet throughout the remainder of their service.
In 1919, the Namhae suffered an explosion in its aft magazine while anchored in Gyŏngsan harbor. The cause of the explosion is unclear, but was most likely a result of poor safety measures in handling ammunition. The ship remained afloat after the blast, but its aft turret was badly damaged on the inside and no longer operational. The damaged guns were removed from their mounts in preparation for installation of a new turret, but further inspection found warping in the structure around the barbette, and the Navy determined that the cost of a major overhaul was prohibitively high given the ship's obsolete status and the aft turret remained closed to crew.
Both ships were disbanded in 1923 under the terms of the Septentrion Nine-Power Naval Treaty, which set limits on the number of ships Menghe could retain. The Donghae was scrapped at the Gyŏngsan Naval Yard, while the Namhae was disarmed and used as a target ship under the terms of the treaty.
Ships in class
| Name | Laid down | Launched | Commissioned | Fate |
|---|---|---|---|---|
| Donghae | June 29, 1908 | May 10, 1909 | April 12, 1911 | Scrapped 1923 |
| Namhae | July 24, 1909 | November 9, 1914 | August 19, 1916 | Converted to target ship 1923 |