The Delfinen class had a standard displacement of 595LT and 643LT when submerged. They measured 54.5m (178.8feet) long with a beam of 4.7m (15.4feet) and a draught of 4m (13feet). The submarines were propelled by two shafts powered by two B&W 1200bhp diesel engines and two BBC 1200lk=on0lk=on electric motors. The submarines had a maximum speed of 16kn both surfaced and submerged and a range of 4000nmi at . The submarines were equipped with passive and active sonar and a schnorkel. The Delfinen class were armed with four 5330NaN0 torpedo tubes located in the bow. They had a complement of 33.
| Delfinen class | ||||||
| Number | Name | Builder | Launched | Commissioned | Decommissioned | Fate |
|---|---|---|---|---|---|---|
| S 326 | Naval Dockyard, Copenhagen, Denmark | 4 May 1956 | 1 August 1961 | 2 August 1983 | Sold for scrapping 11 September 1984.[1] | |
| S 327 | 20 February 1957 | 1 August 1961 | 31 July 1989 | Sold for scrapping, 3 December 1991.[2] | ||
| S 328 | 22 May 1958 | 1 August 1961 | 6 August 1981 | Sold for scrapping 7 September 1982.[3] | ||
| S 329 | 22 April 1963 | 22 October 1964 | 31 March 1990 | Handed over to the Langeland Fort Museum on Langeland as museum ship | ||
Following World War II, the Royal Danish Navy which had lost the majority of its fleet during the German invasion, was restocked with ex-British Royal Navy submarines on loan and salvaged Danish submarines that had been scuttled during the war. Denmark joined NATO and was assigned the defence of the Baltic Sea which led to an emphasis on submarines. The Delfinen class marked the Royal Danish Navy's first new submarines in the post war era. Designed by the Danish and constructed at the Naval Shipyard in Copenhagen, the first three vessels in the class were paid for the Danish and were constructed between 1956 and 1961. The fourth submarine of the class, Springeren, was financed by the United States and known as SS-554.
The class remained in service until the beginning of the 1980s, when the Royal Danish Navy intended to replace them with former Norwegian s in 1986. Only three Kobben-class units were acquired due to a lack of funds and Springeren remained in service until 1990. Springeren is preserved as a museum ship at the Langeland Fortet Museum.