The Collins class is an enlarged version of the Kockums Västergötland class submarine [REF].
The submarine is armed with six torpedo tubes, and carry a standard payload of 22 torpedoes: originally a mix of Gould Mark 48 Mod 4 torpedoes and UGM-84C Sub-Harpoon, with the Mark 48s later upgraded to the Mod 7 Common Broadband Advanced Sonar System (CBASS) version [REF].