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Sea Trials Commence of Upgraded Gotland Submarine

1:a verkstadsprovturen med HMS Gotland.

On Friday October 19 His Swedish Majesty Ship (HSwMS) Gotland started its sea trials at the Saab shipyard in Karlskrona, after a comprehensive Mid-Life Upgrade (MLU) to ensure its operational service to Sweden beyond 2025.

HSwMS Gotland is the first of two submarines being upgraded with the mid-life modifications, which consist of upgrades of onboard systems and technology, sustaining the submarine’s operational capability to meet future naval challenges.

1:a verkstadsprovturen med HMS Gotland.

“The sea trials mark an important phase in the MLU project. This is the first time the crew will be able to operate the new systems in the true environment. After extensive training in the land based training facility, they will now be able to see the true potential of their submarine”, says Gunnar Wieslander, Senior Vice President, head of business area Kockums at Saab.

The upgrade process entails many important systems, such as the Stirling Air Independent Propulsion (AIP) for longer duration underwater and the combat system. Even the traditional optical periscope is replaced with a new optronic mast for enhanced surveillance. More than 20 systems on-board the upgraded Gotland-class will be implemented in the new A26 submarine for Sweden. The Gotland MLU therefore contributes to the test and qualification of some of the innovative solutions to be implemented in the future Swedish A26 submarines.

After tests and verifications, the submarine will be delivered back to the Swedish Navy.

Please visit for additional images and infographics regarding MLU of Gotland.

Facts about the MLU of Gotland

Length overall 62 m

Beam 6.2 m

Displacement 1580 tons (surfaced)

Weapons Torpedoes, bow tubes

Propulsion Single-shaft, diesel-electric and Stirling AIP

Endurance Weeks (submerged)

Hull Single pressure hull, two pressure tight compartments

Crew 25

For further information, please contact:

Saab Press Centre,

+46 (0)734 180 018

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Saab serves the global market with world-leading products, services and solutions within military defence and civil security. Saab has operations and employees on all continents around the world. Through innovative, collaborative and pragmatic thinking, Saab develops, adopts and improves new technology to meet customers’ changing needs.