[Legbreaker]

Further to my last post, I think this quote from Wiki is worth thinking about.

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 USS Abraham Lincoln, 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 70 metres (230 ft) 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 USS Tarawa and the dock landing ship USS Rushmore.

Later that year, during two weeks of combat trials in August, Sheean demonstrated that the class was comparable in the underwater warfare role to the Los Angeles-class nuclear powered attack submarine USS Olympia. The two submarines traded roles during the exercise and were equally successful in the attacking role, despite Olympia being larger, more powerful, and armed with more advanced torpedoes. In 2003, a Collins-class boat carried out successful attacks on two USN nuclear submarines and an aircraft carrier during a multinational exercise. The repeated successes of the class in wargames and multinational exercises earned the Collins class praise from foreign military officers for being "a very capable and quiet submarine", and recognition of the boats as a clear example of the threat posed to navies by modern diesel submarines.

It may not be a Soviet sub, but it does demonstrate the ability of a diesel powered sub to quietly operate in and around a carrier task force without being detected soon enough to stop a successful attack.