The Sheean is an Australian Collins Class submarine of 2450 tons displacement surfaced. She is powered by three Hedemora VB 210 18-cylinder diesel engines and a 3.5 mega watt Jeumont-Schneider motor, giving a top speed of over 20 knots submerged and 10 knots on the surface. She is armed with a sub harpoon ship-to-ship missile system, and six 21 inc...