Java-class cruiser

Design

Development

During the early 20th century, the primary purpose of the Royal Netherlands Navy was the protection of the oil-rich and economically vital Dutch East Indies. The largest threat was from the rapidly expanding Japanese Empire and its significantly larger and more powerful navy. Unable and unwilling to build a comparable force, the Netherlands focused on maintaining a small but high-quality fleet designed to delay any invasions until reinforcements from other European powers with similarly threatened colonies could arrive. In 1914, the Navy planned for a large expansion of its fleets, concerned about Japanese naval expansion and the need to maintain Dutch neutrality during World War I. One major aspect of the plan was the Java-class cruiser, intended to outperform all comparable cruisers, especially those of Japan. The new Japanese Chikuma-class scout cruiserwith 5,000 LT displacement, eight 15 cm guns and a top speed of 26 knwas used as a template for what the new design needed to surpass.

The first two cruisers were ordered in 1915. However, Dutch naval architecture firms lacked experience with such ships. Instead, contracts for their design were offered to British and German companies. The contract was given to Germaniawerft who emphasized German technical assistance and German-made guns, turbines, and other equipment.

Characteristics

When the ships were designed in 1915, the Navy believed they were the most powerful and modern cruisers in the world. Armed with ten Bofors-built SK L/50 5.9 in caliber guns in single mountstwo on the bow, two on the stern, and three broadside guns on either sidethe ships were the most well-armed of their kind. Anti-air weaponry consisted of two 7.5 cm guns located below both masts, and four 12.7 mm Vickers machine guns. They had an overall length of 155.3 m, a beam of 16 m, a draught of 6.1 m, displacement of 6776 t and were 8339 t at full load.

As designed, the ships were powered by three turbines supplied by eight boilers that provided 73,000 shp through three propellers for a top speed of 32 kn. Due to a bunkerage of 1,200 tons of oil, the ships had a cruising radius of 3600 nmi at a cruising speed of 12 kn. The waterline belt was 7.5 cm thick for most of the ships' length, which tapered to 5.0 cm towards the stern. The armored deck was 2.5-5.0 cm, funnel uptakes 5.0 cm, bulkheads 60 mm, and the conning tower 12.5 cm thick. The main guns were protected by gun shields which were 10.0 cm at the thickest.

Celebes, the third ship of the class, was intended to operate as the flagship of the East Indies Fleet and was about 3 m longer and 155 t heavier than the rest of her class. After she was canceled, Celebes role of flagship was filled with the commissioning of in 1936.

Construction

Reliance on foreign expertise soon backfired as the German arms industry buckled and collapsed as a result of World War I and resulting political unrest throughout Germany. Construction stalled as materials were delayed and some parts never arrived at all. After the war, the Dutch government questioned the need to build new, expensive, warships. As a result, the newly-started Celebes was canceled and work on the other two ships was suspended. During the pause, the government explored alternative uses for the cruisers, including a proposal to convert them into English Channel ferries. Ultimately, the Navy successfully argued that completing the ships would be more cost-effective than abandoning them, and progress resumed in 1920. Both ships were launched over the next year as parts were sourced from countries such as the United Kingdom and Sweden, although eight SK L/50 5.9 in guns were found in a Krupp warehouse and were incorporated. Construction was further delayed by a series of strikes, the newly introduced 8-hour work day, supply issues, and a fire that destroyed turbines intended for the future Sumatra. New turbines for the cruiser were sourced, allowing her to produce 82,000 shp.

The significant delays of her construction saw the ships outdated by the time she entered service, primarily regarding their armament. By 1922, the Washington Naval Treaty created a new standard of cruiser equipped with 203 mm guns, which Japan heavily invested in. In addition, the single-barrel weapons protected only by gun-shields had already been replaced by enclosed, multi-gun turrets fed by independent magazines in other navies.[[File:Awm 045393 HNLMS Java.jpg|thumb|Java after her reconstruction, featuring thicker and shorter masts.]]

Modifications

Soon after the two ships entered service, they were fitted with two derricks and two floatplanes. Initially, the ships were equipped with the Fairey S.III, although it was fragile and replaced by the Fokker C.VII-w in 1927, itself later replaced by the Fokker C.XI-w in 1937. During the mid 1930s, the ships were refitted: the forward mast was rebuilt and shortened, and the anti-air weapons was expanded. Sumatra received three twin 4 cm Bofors guns, while Java had two.

Ships

Service history

''Java''

After she was commissioned, Java sailed to the East Indies and visited several cities throughout East Asia and Oceania. In 1937, she returned to Europe to escort convoys through the Strait of Gibraltar during the Spanish Civil War and underwent a refit in 1938. By 1939, she continued to escort convoys in Asia before she joined an Allied fleet and participated in several attempts to repulse Japanese invasions of the East Indies. After several failed attacks, the cruiser was torpedoed and sunk while attempting to prevent the invasion of Java during the Battle of the Java Sea. Her outdated design proved fatal as she lacked modern protections and redundancies. She was struck by a Japanese torpedo on her stern, which caused her aft magazine to detonate. The resulting explosion ripped apart the ship, and she sank in about 15 minutes with most of her crew.

''Sumatra''

Sumatra likewise operated with Java in the East Indies. Upon Javas return from her 1938 refit, Sumatra sailed to Europe where she also escorted convoys during the Spanish Civil War and served as a training ship. She was docked and awaited her own refit in May 1940 when Germany invaded the Netherlands. She then fled for the United Kingdom and was placed under the command of the British Royal Navy. The next month, she sailed for Canada to evacuate members of the Dutch Royal Family and later patrolled the Caribbean and mid-Atlantic for commerce raiding. Later that year, she returned to the East Indies, was retrofitted, and had her crew reassigned to other vessels. After war was declared against Japan, the cruiser fled Asia with only a portion of her crew and machinery online. She sailed around the world and arrived back to the United Kingdom. The Royal Navy viewed her as obsolete, and had her disarmed to replace worn-out weapons on other Dutch vessels and later had her sunk as a breakwater during the construction of an artificial harbor after the Invasion of Normandy.

Citations

Sources