On a cold, snowy morning in the bustling German port city of Kiel, Singapore launched its fourth Invincible-class submarine — the Inimitable. Built by the Republic of Singapore Navy (RSN), Defence Science and Technology Agency (DSTA) and German manufacturer thyssenkrupp Marine Systems (tkMS), it is part of a four-submarine fleet that replaces the Navy's Challenger- and Archer-class vessels. The first...