Singapore Navy’s German Invincible-Class Sub Begins Sea Trials

The Republic of Singapore Navy (RSN)’s first Type 218SG Invincible-class submarine being built by Germany’s Thyssenkrupp departed for sea trials Monday.

The vessel is first of four customized Type 218SG diesel-electric submarines that are slated to be delivered from 2021 to replace the four refurbished Challenger- and Archer- class submarines that RSN has operated for more than two decades. The old submarines were formerly being used by the Royal Swedish Navy.

RSN has named the submarines Invincible, Impeccable, Illustrious and Inimitable.

Displacing 2,200 tons (submerged), these submarines will be manned by a crew of 28 and have a speed in excess of 15 knots underwater. They are 70 meters long and 6.3 meters in diameter. Their armament will be deployed from eight 533mm torpedo tubes. Type 218SG boats are based on TKMS Type 214; with elements from the Type 212A such as the X ruder section that will allow operation in shallow littoral waters.

The Invincible-class submarines are are fitted with Air Independent Propulsion (AIP) systems based on Fuel Cell technology, which will allow the submarines to stay submerged about 50% longer. They are also carrying a combat system designed by both Atlas Elektronik and ST Electronics. Special Forces operations are a major feature of the Type 218SG design, with an Horizontal Multi-Purpose Lock (HMPL) located at the bow, in addition to the 8x torpedo tubes.