Edit: 2nd of April 2024
The content of this specific article is an April Fools joke.
Greetings, it’s the start of a new month and with it I have a special article for you. This article is based on the “van Kanten” archives that have opened after the first quarter of the year had passed. The primary source is a summary of the report on ‘Large Capital Ships for the Netherlands’ by various compilers. Please enjoy.
During the mid 1930s the Dutch reviewed their naval grand strategy. The increased tension on a global scale brought doubts in the viability of the deëscalation attempts of the big naval treaties thus relaxed spending of the 1920s had to go out of the window. However, the economy and public support still had not caught up to the international situation. A balance had to be struck and this required careful observation.
The fundamentals were reviewed. For the defence in Europe no change in doctrine was necessary. A fleet based around mine and submarine weaponry supported by gunboats was the most efficient here. Other endeavours made little sense considering the possible adversaries and geography. The only concerns were around the training of personnel and accommodation of the colonial fleet that could end up needing maintenance in the Netherlands.
As far as colonial tasks went, for the West Indies no more than a colonial gunboat or fleet leader for police actions was needed, with the tiniest of submarine support. The weight of the question fell on the East Indies as this had diverse and vastly contradicting needs.
A sufficient presence was needed to police the busy waters in peacetime. In case of war the situation was different. The primary assailant was expected to be Japan. No other country would benefit much if at all from disrupting the status quo. And for this three cases were envisioned. A coup de main, coup de grace and total war. The latter of which entails the involvement of allied factions.
The weakest point of the Japanese navy was identified to be the merchant fleet and its distance to the Indies. Mines and submarines could still provide a good defence near the bases and narrow straits. A well organised defence ought to ensure any invading forces could not establish a sufficient land presence this way. Cruisers would aid in the early reconnaissance of the enemy, provide medium level artillery capabilities to cover the submarines and could guard reinforcement stations.
The crux of the danger laid in the ability of the Japanese to support their fleets with fast and powerful heavy cruisers. Even worse would be the addition of a dreadnought or dreadnought cruiser. If local control could be established by the Japanese they would be able to resupply and station aircraft carriers.
For most situations the current plans had so far sufficed. But it was found that a heavy element was needed that could A) Aggregate against local mobility of the heavily armed and speedy heavy cruisers. B) The enemy could not deter the heavy element from operating in the area through the least effort.
Two design philosophies emerged.
The former focussed around well armoured ships. Forsaking the speed needed to operate offensively. Armour was considered cheaper, more future proof and maintenance free. Armament was also kept to the minimum and took inspiration from the Passchen philosophy.
Two triple turrets of roughly 406 mm were desired. This was sufficient to deter against all of the existing Japanese battleships. Questions were put on whether it would be sufficient against the future Japanese battleships of 45.000 t with 41 cm (or even a rumoured 457 mm, but it was expected that those would bring other vulnerabilities). The conclusions were that if there was any doubt, an aggressor wouldn't risk their pride ships. However a weakness in this plan was the lesser speed could be exploited and the ship attacked from a range beyond retaliation.
For the secondary battery initially the 12 cm L46 in new twin mounts was designated. Correspondence with Bofors indicated the possibilities for an autoloading twin mount of at least 24 rpm or possibly 36 rpm. However the technology remained relatively speculative. The 12 cm being a dual purpose weapon also negatively impacted armour piercing capabilities and the gap between effective 406mm fire and 120mm fire was considered too large, leaving a hole against formations of large destroyer leaders and light torpedo cruisers. Commitment to a fully dual purpose battery was deemed not feasible and weaponry of at least 15 cm was deemed necessary for this task. With these considerations in mind a modest 20 cm battery was added following the same principles.
Speed requirements were deemed as followed: A) Fast enough to not be bound into combat with a 28 kt Battleship. B) Through the use of its firepower, gun range, islands and speed, a speed fast enough to not get isolated by cruisers and lighter elements. Considering the geography the speeds of 25kts and 27 kts were selected to meet those requirements.
The original power plant consisted of 3 shafts powered by 6 Yarrow Boilers built by Werkspoor, Amsterdam and 3 Parson-Geared Turbines made by De Schelde, Flushing. Initial computations concluded a speed of around 25 kts with this propulsion. This was rejected on two fronts. Firstly doubts were put as to whether the 25 kts could be reached satisfactionally. A slightly higher speed was desired. Secondly there was preference to separate the engines longitudinally and add an armoured bulkhead or room between the units.
Aside from the propulsion there were also concerns regarding the combat performance of the ship. Two variants were drafted up to deal with separate issues. It was theorised that the slow speed meant encirclement by cruiser forces. And thus to augment the secondary battery against cruisers another pair of turrets would need to be added which would ensure six barrels could point in every direction. It would also allow engaging two targets at the same time. Another idea was to add an extra turret. This would make the long range lethality against battleships a more serious threat - and would also give security in case one turret was rendered inoperable. The idea came with the consequence of having to add a much taller barbette and lengthening the ship including the citadel heavy armour by about 20 metres.
The Bureau Scheepsbouw sent out an investigation at the companies capable of making 406 mm guns. Hereto only correspondance with the foreign Bofors, Krupp and Schneider have been found as well as Artillerie Inrichtingen and Nederlandse Springstof Fabrieken. Due to not having experience in production of large projectiles there seems to have been special interest in new development of shells. Including the ability to locally produce or at least assemble the munitions. Hence why studies were requested from these companies.
For the secondary battery more local options were sought. Wilton-Fijenoord was seen as the prime candidate and held the advantage of being involved with Bofors. Meanwhile, Stork remained an option after their failed bid with Vickers on Hr Ms De Ruyter’s 15 cm cannons.
Slagkruisers
An alternative proposal was achieving local control through the means of speed and firepower. If the heavy element was faster then it would not have to concern itself with protection as much. It would also play in much nicer with the existing doctrine of submarines, the risk-strategy and the large distances of the terrain. However, to ensure its efficacy a firepower advantage at longer ranges was needed. In the current state Japan could use all their forces in a surprise attack, including their first rate battleships. This meant ordnance more modern and powerful than the Japanese 41 cm was needed and the range of 406 mm cannons that was available may not meet the required criteria.
Krupp offered a 42cm cannon but was at a crude stage of design. Vickers was contacted for their rumoured 16½”/419 mm cannon but it turned out that no such cannon existed. Although they did propose they could produce such a weapon. Another solution was found in a Schneider designed 17” cannon.
For the secondary battery a setup of twin 12 cm L46 DP mounts was chosen initially, placed in four quadrants with two turrets each. Shortly after it was found that the turrets were both heavier but also more capable than conceived so this was later brought down to six total. There was a proposal for moving two to four mounts into the centreline, but endeavours seem to not have succeeded. Compared to the pantserschip design any heavier secondaries were not considered necessary due to the difference in speed allowing for more flexibility.
Armour was exceptionally modest and optimised for longer ranges. The biggest hurdle seemed to have been the belt angle as the sharper angling in conjunction with the torpedo defence system would cut into the machinery space available. Furthermore, because of the expected longer ranges the angle and belt height had to be configured to not have any shells go underneath.
It was investigated how enlarging the ship could solve some of the issues present in the early conceptions. However, the displacement would increase to well over 50.000 tons. This would neither be economically nor politically feasible. Ideally the design would have to stay below 40.000 tons to not alert the Americans and Japanese who were constructing 40 to 45 thousand ton ships. Other considerations were the shore facilities for such large vessels.
Detailed design work continued on the K-series of the project. Cutback had to be made in the deck armour, speed and the aforementioned secondary mounts.
Despite cutbacks in the design it was still considered to increase the armament in other ways. Fears that the new Japanese ships would be armed with 18” cannons and armoured against their own guns became a serious consideration. But big guns tended to have a short barrel life. To cope with the circumstances it was proposed to use twin 46 or 48 cm guns with a barrel length of 40 calibres. By using a lighter shell with proportional charge a more stable and accurate trajectory could be acquired relative to the smaller bore diameter option.
However, range would be drastically reduced. This would have some issues on maximum range performance against the vertical belt armour. Against horizontal armour this would have the opposite positive effect. At such ranges ammunition supply would be insufficient and thus needed further expansion. To deal with extremely well armoured targets at intermediate ranges it was proposed to keep extra charges in reserve to fire some shells at full power at the cost of barrel life. A side effect of the generous ammunition supply was the ability to keep both turrets on the same deck level due to the increased distance between each other made by the magazine space.
A point up for debate was the catapult arrangement. Preferred was a traversable catapult or two aimed forwards at an angle in a ‘V’-formation. But such an arrangement gave clearance issues with the turrets and crane. It was decided to use a fixed transverse catapult. As it would fit much easier and allow for wider wingspan model aircraft. It did make it more difficult to launch into the wind. But that problem could be partially alleviated if the catapult was fit to launch both to starboard and port side. Another plus was that the crane could be positioned in a more favourable position.
After more detailed information on possible weapons trickled in the Dutch managed to adjust particulars. The munition supply was overestimated and the turrets were brought in closer. The reduced belt length freed up enough armour to in theory raise the barbette of B turret. Giving the project a more conventional assortment of main battery.
The project sadly came to a swift end with the introduction of Furstner. Whilst the designs had merit they were seen as ‘overkill’ and the implementation of these ships unfeasible in the short term. It was decided to focus on ships more of the Dunkerque type which ought to be much easier to transition to.
The cruiser screen
In addition to the heavy ships a set of lighter escorts had to be commissioned for reconnaissance and escort duties. Whilst destroyers and fleet leaders were too small to specialise, the cruiser screen would have to be more fit for their role. A number of new guidelines were set in accordance with the change in role: A) Be able to resist 20 cm fire at long distances and resilient to 14 cm and 15,5 cm fire at most distances. B) Excellent firepower to protect the heavier element against targets up to light cruisers and modestly armoured heavy cruisers. C) A strong long range AA fire to escort the heavier element. D) A speed of 33 knots.
A relatively large ‘light’ cruiser of approximately 10.000 t was appointed to most fit this role. To properly achieve the criteria the main battery had to be dual purpose and of good long range characteristics. Initial thoughts went out to a battery of 4 triple 15 cm turrets. Wilton-Fijenoord, which had recently taken over HIH Siderius’ capabilities, was tasked in combination with Bofors to develop such a weapon.
Wilton-Fijenoord noted that it could produce a 15 cm L70 cannon firing a 50 kg shell at roughly 980mps. However, although Bofors could draft up an automatic DP mount it could not miniaturise the design to specifications. A different proposal was soon drafted up in accord with Wilton-Fijenoord. The new turret would mount two 17 cm L/65 SK in a twin DP automatic mount of 55° elevation. Barrel length would be approximately 11200 mm, gun weight around 13 t and the mount 140 t. It would fire a 75 kg shell at roughly 950 mps. Rate of fire was expected to be 18 rpm with automatic loading. Provisions were made for a manual backup hoist.
For the secondary battery of these cruisers 7,5 cm was deemed logistically the preferred option as the Dutch had numerous models of those in service and the tools and experience to maintain them. However something with a bit more reach was desired for escorting vessels as well as those that fought in the pacific, where planes were expected to operate higher. The 12 cm checked those marks but was very sizable due to its autoloader, rendering it only viable on battleships or as a main armament. One idea thusly proposed to scale down the cruiser entirely so that the 12 cms replaced the 15 cm cannons. But it was addressed that such a vessel would not fare well against a Mogami-class cruiser.
Two models were in consideration. The Swedish 10,5 cm twin and the German 10,5 cm SK C/33 twin. Preferably four twins would be mounted on the ship. Two at starboard and two at portside. However, no definitive choice was made during development. And the project was cancelled in favour of starting development on the Eendracht-class.
After World War Two
With the war over and the Netherlands in need of rebuilding both its armed forces and naval forces a new fleetplan was drafted. The desired fleet composition was for 3 reinforced task forces with 1 carrier, 1 battleship, 1 transport and 1 repair ships each. Along with 4 cruisers and 12 destroyers for their escort.
Because the Netherlands lacked experience in carrier operations and reinventing the wheel was out of the question it was sought to acquire those vessels and experience from their British ally. The battleship however could be natively developed. The primary role for these battleships were mobile fortresses or anchor points. Top speed was not seen as an important trait as the ships would not aggregate alone. Instead, cruise speed and operation range were much more valued. As far as firepower was concerned it was noted that the guns had to be as large as possible, based on a ship that the economic situation would dictate.
Further new points of importance were the electronic suite. New RDF and asdic rooms were scheduled which increased the power usage and required space of the ship. Underwater protection also needed to be changed with much stronger bulkheads, more reserve buoyancy and increased pump throughput.
However, none of the new developments were as important as the changes in consideration for air attacks. Aircraft could now engage ships with heavier ordnance and at higher speeds than before. Experience from the pacific war showed that whilst aircraft could definitely sink battleships, such as what happened to Yamato, it would require a disproportionate force to do so effectively. With many aircraft deployed and lost for marginal success in hits. Allied ability to repel kamikaze attacks proved that anti-air firepower is still able to stop air attacks provided this area is not squandered during development.
With all the above in consideration, the designers came to a design of around 45.000 ton. The design had a torpedo defence depth of 7,5 metres including a 4,5 metre space between units. If instead the rooms were placed adjacent the depth could be increased to 9,75 metres. Combined bulkhead armour would be 100 mms thick. The deck armour would be a total of 200 mms; enough against 1000 kg bombs. Anti aircraft guns would consist of 10 twin HA/LA automatic 6-inch turrets. Two in the centreline and two pairs per side. For close range the AA defence consisted of at least 14 twin 40 mm triaxial mounts.
To achieve the required space for the AA-suite it was decided to cut the main battery down to only two triple turrets. The preferred weapon would be a Krupp developed 48 cm cannon. This choice came down to availability, the weapon was thought to be in production already. By employing the German workforce it was thought that the impact on the German economy could be reduced by avoiding mass lay-offs from the war’s end. In addition, this gave extra time for the Dutch industry to prepare for taking over the development and maintenance of this weapon.
(Image: the post-war Battleship)Ultimately, the 48 cm cannon turned out to be entirely theoretical which meant that another alternative had to be found. The closest alternative would be the British 18-inch cannon but that was a very outdated design. But before this trouble could be resolved the project came to a swift end. It was decided that instead of reinforced task forces the new fleetplan would consist of 3 light task forces.
Author Post Scriptum:
I hope you enjoyed reading this and I do wonder how long it took you to realise this was all an elaborate prank for the first of April. In any case, until next time.
Sources:
Nationaal archief, 61 Persoonlijk archief van Kanten, Inventaris Nr. 71.01, Zware slagschepen voor Nederland, onbekende auteur.
Regionaal archief Morensloot, 11 Archief Koninklijk Leger en Marine, Inventaris Nr. 1907.
Regionaal archief Lenten, 9 Verrichtingen Koninklijke Marine, Inventaris Nr. 107
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