The Walrus-class submarine is the only submarine class currently in operation in the Royal Netherlands Navy. The boats have been in service since 1990 and are all named after sea mammals.
Background In 1974, the Royal Netherlands Navy announced, through the Ministry of Defence's 10-year plan , that it wanted to replace its aging s.H. Vredeling, C.L.J. van Lent, A. Stemerdink, p. 61. Since the 1960s, the Royal Netherlands Navy had been conducting studies and research into a suitable replacement attack submarine. This research initiative concluded that the Netherlands should build conventional diesel-electric submarines, as nuclear submarines were costly and could only be constructed, crewed, and maintained by countries with major navies such as the United States, France and the United Kingdom. Nonetheless, even with the diesel-electric submarine, the Dutch government sought to work together with international allies to reduce construction costs.
Between 1975 and 1978, the design of the Walrus class was for the most part completed, and included many improvements which would result in new, state-of-the-art submarines that would mark a significant improvement over previous submarines used by the Royal Netherlands Navy. For example, a special kind of French-produced steel was used to construct the hull of the Walrus-class submarines; this steel proved to be more elastic, allowing submarines of the class to dive deeper than previous submarines.Miller and Miller (1986), p. 171. Furthermore, there was a focus on automation which was aimed at decreasing the manpower required to operate the submarines, while also making them more effective against threats.
On 19 June 1979, Minister of Defense Willem Scholten signed a contract worth 425 million guilders with the Rotterdamsche Droogdok Maatschappij (RDM) to build two submarines to replace the Dolfijn-class submarines, with the construction of the second boat to commence the following year. Soon, RDM noticed that the new submarines could not be built the same way as the s; it had to use new techniques to build the submarines. Furthermore, the design was constantly modified to incorporate new developments in the submarine world, which led to issues that slowed the building process. Nonetheless, construction continued and on 11 October 1979, was laid down. Two years later, on 24 September 1981, was laid down.
Unexpectedly, on 19 February 1983, RDM's parent company Rijn-Schelde-Verolme declared bankruptcy, despite successive governments providing 2.2 billion guilders in state aid to RSV. This was problematic because the construction of the Walrus-class submarines was far from completion. To ensure construction of the submarines continued, RDM was re-established as an independent company. Furthermore, the Royal Netherlands Navy ordered an additional two Walrus-class submarines earlier than planned to assist RDM financially. However, at this time the Walrus-class submarines were facing many problems. One of these problems was that the specifications of the Walrus class submarines were only finalized in 1984. Since construction had already started by that time, the first two boats had to be lengthened by 1 meter, at a cost of 10 million Dutch guilder per boat, to fit all equipment.
New problems arose on 14 August 1986, when the command centre of Walrus caught fire, while it was still on a scaffold in the shipyard.de Bles, Boven and Homburg (2006), p. 104 The fire lasted about five hours, and resulted in immense damage to the submarine; the command center was completely burned out. While some equipment could be rescued, most had to be replaced. This delayed the construction of the submarines once again because the equipment that was ordered for the next boats had to be transferred to finish the Walrus.Grove (1990), p. 179. The costs of the resulting damage from the fire was 225 million guilders, which was fully covered by insurance.Horneman (2018), p. 17. The exact location, origin and cause of the fire was never established.Nooteboom (2001), p. 148. Presumably, the fire was caused in the vicinity of the corporals and men's washroom by a defect in the electrical work lighting. Repairs were reported as complete in 1987, but had so delayed construction of Walrus that the second submarine (with construction number 349) was put into service as the first of the class, with the name HNLMS Zeeleeuw (sea lion). HNLMS Walrus was put into service two years later. The two other boats were put into service as and (porpoise). The delays meant that , and of the Dolfijn class had to remain in service longer than planned. All the problems, delays and rising costs were eventually dubbed by the Dutch national parliament as the "Walrus-affair". Nonetheless, at the time of their commissioning, the Walrus-class submarines were considered to be one of the most modern and advanced conventional submarines in operation.
Design
The Walrus-class submarine was designed by Jan Jaap van Rijn, at the time Chief Bureau of Submarines (Dutch: Hoofd Bureau Onderzeeboten) at the Directorate of Materiel of the Royal Netherlands Navy (Dutch: Directie Materieel van de Koninklijke Marine).
The Walrus-class submarines are unusual in that instead of a cross-shaped assembly of stern diving planes and rudders, they mount four combined rudders and diving planes in an "X" configuration. This tail configuration was first tested in 1960 on the United States Navy's , and has since been used by the Walrus class, all Swedish Navy submarines since the , the Royal Australian Navy's , the German Navy Type 212A and the Japan Maritime Self-Defense Force's . The X configuration is a complex system and therefore not implemented by many other navies around the world.
The submarines of the Walrus class, when submerged, are silent and therefore difficult to detect by ships, planes and other submarines once they go into hiding. This makes the boats very suitable for combating surface vessels and submarines, protecting friendly units, gathering information, providing early warning detection, and supporting special operations. The submarines can also be used to enforce international sanctions, as they did during the Yugoslav Wars.
The Walrus-class submarines were specifically designed for hunting Russian submarines during the Cold War. However, the Cold War had ended by the time they became operational. Nonetheless, they have provided excellent services in various international conflict situations in which the deployment of the Royal Netherlands Navy was requested. Since the Dutch submarines have acquired a good reputation, they are often part of international exercises, taking part in mock battles.
In March 2023 it was reported that the Dutch government wants to buy Tomahawks for the Walrus class submarines. The Tomahawks would be the Torpedo Tube Launch (TTL) version, which can be fired from the torpedo tubes of the submarines. However, at the same time it was also stated that if the delivery of this version of the Tomahawk would take too long to deliver it might not be feasible to integrate them on the Walrus class, as these submarines will replaced in the 2030s by a new class of submarines. In May 2025 it was disclosed that the Walrus class submarines will not be equipped with Tomahawks.
Operational history
After the Cold War, the submarines have been tasked with many highly confidential intelligence gathering operations, many of which are still classified. They have operated in the Northern Atlantic, Mediterranean Yugoslavian region, the Persian Gulf at Iran and Iraq, and the Caribbean, often upon the request of allies, including the United States.de Bles, Boven and Homburg (2006), pp. 104–105
In June 2010, the Netherlands agreed to deploy one submarine to help combat piracy off the coast of Somalia.
In November 2016, the Russian Navy claimed to have chased off a Walrus-class vessel from a battle group that included the .
Submarine command course
The Walrus-class submarines are used for the Submarine Command Course (SMCC) for both national and international candidates (including the UK, Australia and Canada), selecting and training future commanders of conventional submarines. They are highly rated, with an exceptional reputation.de Bles, Boven and Homburg (2006), p. 105 The Royal Netherlands Navy began this course after the British Royal Navy phased out their conventional submarines.
Upgrade program
In 2007, the Dutch cabinet approved an upgrade of the four operational submarines and recruitment of additional crew to improve overall operational availability. The upgrades were focused on near-shore operations and integration with new weapons, and include: The migration from the MK 48 mod-4 torpedo to the mod-7 version Replacing one periscope with a non-hull-penetrating optronic mast from L-3 KEO which enables the submarine to capture HD footage, both day and night Addition of a mine and obstacle avoidance sonar Refurbishing of the pressure hull Introduction of a new combat management system Modifications to support special operations forces
In 2013, the contract for the Walrus-class (IP-W) Conservation Program was signed. The program covered the preservation of the pressure skin, the replacement of the sonar, navigation periscope and GIPSY combat system, improved communication systems and adaptations to a number of platform systems. The Dutch industry and knowledge institutes were heavily involved in the program via the Dutch Underwater Knowledge Centre.van Kesteren (2020), p. 13.Horneman (2018), p. 82. It was predicted that the upgrade program would lead to an estimated 400.000 man-hours of work for each boat. All four boats were to be modernized by 2019. With the conservation program, the boats can be kept operational until mid-2025. The cost of upgrading the four submarines was estimated to be 94 million euros. The first boat to be upgraded was , followed by , and . The upgrade of Zeeleeuw took longer than expected. Initially the upgrade was expected to have been completed by 2015, but it took until 2016 before the submarine was ready for service again. Currently, Bruinvis is being upgraded at the Den Helder naval base. The Royal Netherlands Navy has also begun to prepare for the replacement of the Walrus-class submarines.
Replacement