100 years under the sea

On 30 August 1914, the first Kockums-made submarine was put to sea. HMS Svärdfisken (Swordfish) left the dock and was ready to be delivered to the Swedish Armed Forces.


In the early 1900s, the Swedish fleet invested in their first submarines, purchasing the submarine Hvalen from an Italian shipyard in 1909. In 1910, Kockums Mechanical Workshop in Malmö announced it  had the ability to build submarines of the same type as Hvalen for the Swedish Navy.

Barely two years later, the Swedish Maritime Administration contacted Kockums and announced that they wanted to sign a contract for two submarines. Production began and in 1913 His Majesty King decided that the two submarines should be named Svärdfisken and Tumlaren.


HMS Svärdfisken and its sister boat, HMS Tumlaren were built at Kockums shipyard in Malmö. They were typical ‘dive boats’, i.e. surface vessels that could dive when needed. These submarines were based on Italian designs and were of the then very modern Fiat Laurenti type with well-structured, long narrow pressure hulls. Svärdfisken and Tumlaren were considered good submarines because of their seaworthiness and high speed. They also had a modern communication system using wireless telegraphy.

The submarines at this time lacked a mast snorkel and because of its design, small battery and poor air purification, Svärdfisken could only be subsurface for a few hours at a time. Conditions on board must also have left something to be desired. One can imagine a few benches in the bow and stern, but for a crew of 21, it must have been crowded.  Neither bathrooms nor a galley (kitchen) are visible in the drawings.

HMS Svärdfisken was at this time a very popular submarine and was in service until in 1936.


Since the production of Svärdfisken, Kockums has produced 73 submarines, the latest is the Gotland-class. Through the years, major developments in submarine production have been made.

One groundbreaking development in submarine history was after World War II when the snorkel mast was introduced which meant submarines no longer had to fully surface to recharge their batteries, but could instead lie just below the surface with the snorkel mast sticking supplying the diesel engine with air.

Another step forward in the development of the submarines came in 1967-68 with the Sjörormen-class (Seaworm-class). These submarines were the first with hulls optimised for being under the water’s surface, enabling them to reach higher speeds subsurface then at surface. Thanks to their streamlined hulls they were much quieter and easier to manoeuvre compared with previous submarine classes.

The most recent groundbreaking development is the Stirling motor, which neither requires a snorkel mast nor the starting of noisy diesel engines to recharge a submarines batteries. Stirling engines are powered by ordinary diesel and pure oxygen in liquid form which are stored on board the submarine.

Saab looks forward to building on the heritage at Kockums. Do you want to know more about Saab Kockums and our advanced naval systems? Please visit our homepage.

Read the full Swedish article here with abstracts from the written conversation between Kockums and Swedish Armed Forces in connection with the order and production of Svärdfisken.