Sea Platforms

Gotland MLU programme targets mid-2018 sea trials

12 December 2017
Both and have been cut in half (aft of the middle tank section) to allow for the insertion of a 2 m hull section. Source: Saab

Key Points

  • HSwMS Gotland and HSwMS Halland are receiving a mid-life modernisation under a SEK2.1 billion contract
  • Both boats are receiving an additional 2 m hull section being inserted by means of a ‘cut and plug’ operation

The first of two Royal Swedish Navy (RSwN) Type A 19 Gotland-class submarines being modernised by Saab Kockums has begun setting-to-work activities ahead of commencing sea trials next year.

HSwMS Gotland , currently inside the main building hall at Saab Kockum’s Karlskrona facility, is due to be redelivered at the end of 2018. Sister boat HSwMS Halland is approximately 12 months behind, with its pressure hull currently split in two at Karlskrona.

Saab Kockums was awarded an SEK2.1 billion (USD248 million) contract by Sweden’s Defence Materiel Administration (FMV) in June 2015 for the mid-life upgrade (MLU) of Gotland and Halland. The MLU, which will extend the boats’ service life through to 2030, is designed to address obsolescence issues, ensure compliance to updated safety and information security requirements, improve signature performance, upgrade the combat management system, replace the ship management system, introduce a new navigation suite, modernise the sensor package (including a new Safran optronic mast), upgrade the Stirling air independent propulsion plant to Mk 3 standard, and add a diver lock-out chamber.

“This is quite a big programme,” said Anders Otterlund, Saab Kockums’ MLU programme manager. “We are performing a mid-life upgrade and general overhaul in parallel, and also an upgrade to the training facility.”

Gotland was delivered to Saab Kockums in late 2015. “It is two years to do the stripout and rebuild phase,” said Otterlund, “followed by another year for setting-to-work, factory tests, harbour acceptance tests, and sea acceptance tests”.

As part of the MLU, both boats are being lengthened by means of a ‘cut and plug’ operation. The new 2 m hull section, inserted aft of the middle tank section, contains sea water cooling, fresh water cooling, and water chiller plants.

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