The Royal Netherlands Navy will retire two Walrus-class diesel-electric submarines, to enable the other two to remain in service into the mid-2030s, when the new boats are expected to start arriving. In mid-2021 it was indicated that a revised plan envisaged taking a replacement decision in 2022 and to have the first vessel in service by 2028, with the first two boats to be in service by 2031. However, in October 2021 it was reported that this timeline was no longer feasible. Instead, the Dutch Ministry of Defence signaled that the envisaged dates would have to be “substantially adjusted”, possibly incorporating a life extension refit for the existing Walrus-class boats.
In November 2014, the Dutch Minister of Defence announced plans to replace the Walrus-class submarines in 2025. By 2017, there was still no political agreement on the quantity or type of new submarines to be ordered; nor the tasks they were expected to perform. The Minister of Defence, however, delayed the replacement by two years, until 2027. Roughly, there are two groups in the Dutch parliament – one in favor of replacing the Walrus-class by an equally capable class of large diesel-electric submarine, and the other in favor of choosing a cheaper solution of smaller diesel-electric, similar to Swedish and German submarines.
The Walrus-class submarine is the only submarine currently in operation in the Royal Netherlands Navy. The boats have been in service since 1990 and are all named after sea mammals. The Walrus-class 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 U.S. Navy’s USS Albacore, and has since been used by the Walrus class, all Swedish Navy submarines since the Sjöormen class, the Royal Australian Navy’s Collins class, the German Navy Type 212A and the Japan Maritime Self-Defense Force’s S?ry? class.
The two older boats, HNLMS Walrus (S802) and HNLMS Zeeleeuw (S803) will then be cannibalized for parts for the two younger boats. Zeeleeuw is a Walrus-class submarine of the Royal Netherlands Navy. She entered service in 1990 as the first submarine of the Walrus class, after the intended lead ship, HNLMS Walrus, was delayed for a long period following a serious fire during construction. Walrus was laid down on 11 October 1979 at the Rotterdamsche Droogdok Maatschappij yard in Rotterdam. She was launched on 28 October 1985, but on 14 August 1986 an electrical fire broke out on board causing damage costing ƒ225 million(€100 million) to repair.