Full Cycle Docking is the major recertification and upgrade docking for the submarines.
Dechaineux is the fourth submarine to complete this upgrade and arrived in its home port of Fleet Base West, Western Australia after an intensive sea-trials period to prove its systems.
To help provide an increased focus and scrutiny of the submarine sustainment program the Government formed the Australian Submarine Program Office (ASPO) earlier this year.
During its full cycle docking Dechaineux was fitted with the BYG-1 combat system and Mark48 Mod7 heavyweight torpedo, the third of the class to receive these upgrades.
The combat system and torpedo have been developed under a joint program with the US Navy.
The combat and weapon system upgrades, together with an augmented Special Forces deployment capability fitted to Dechaineux in the docking, make it Navy's most capable submarine.
HMAS Dechaineux joins HMAS Waller and HMAS Collins, both currently operating from Fleet Base West.