Name Dolfijn class Succeeded by Zwaardvis class Built 1954-1966 | Operators Royal Netherlands Navy Subclasses Potvis class In service 1960-1992 | |
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The Dolfijn-class submarines of the Royal Netherlands Navy are a class of four submarines; Dolfijn, Zeehond, Potvis and Tonijn. They were built in the late 1950s and the early 1960s. They were the first indigenous submarines built for the Royal Netherlands Navy after World War II.
Design
The Dolfijn class was a special Dutch design and had three separate pressure hulls arranged in a triangle and enclosed in external steel casing. The upper hull for the living/working part of the crew and the lower two hulls were for the engines, batteries and storage rooms. This allowed the submarine to dive much deeper than other submarines from the late 1950s, with a test depth of 200 metres (660 ft). The designer was Max F Gunning.
The order for a second group of boats, also known as the Potvis class, was postponed in the late 1950s while the possibility of building a nuclear powered submarine was considered and rejected. The order for two boats was re-instated in 1962. These boats had their diesels replaced and electronics updated in 1978-79.
Zeehond was converted into a trials ship by RDM shipyard in Rotterdam in 1990 and used as a technology demonstrator for a closed cycle diesel air-independent propulsion system until 1994.