During several multinational exercises and wargames, the "Collins" class has demonstrated its effectiveness in the hunter-killer role by successfully attacking both surface warships and other submarines. In late May 2000, "Waller" became the first Australian submarine to operate as a fully integrated component of a USN carrier battle group during wargames. "Waller"s role was to search for and engage opposing submarines hunting the aircraft carrier , a role in which she performed better than expected. A few days later, as part of the multinational exercise RIMPAC 2000, "Waller" was assigned to act as an 'enemy' submarine, and was reported to have successfully engaged two USN nuclear submarines before almost coming into attacking range of "Abraham Lincoln". "Waller" performed similarly during the Operation Tandem Thrust wargames in 2001, when she 'sank' two USN amphibious assault ships in waters just over deep, although the submarine was 'destroyed' herself later in the exercise. "Waller"s second feat was repeated by "Sheean" during RIMPAC 02, when the boat was able to penetrate the air and surface anti-submarine screens of an eight-ship amphibious task force, then successfully carry out simulated attacks on both the amphibious assault ship and the dock landing ship .