"Sydney" had been originally slated for replacement in the 1960s, with rumours circulating that the new ship would either be an amphibious assault ship of the United States "Iwo Jima" class, or the British carrier . The assault ship rumour was proven false by the early 1970s, while the acquisition of "Hermes" was still under discussion in the 1980s as a possible replacement for sister ship HMAS "Melbourne". Following the decommissioning of "Sydney", the Australian Defence Force did not possess a long-range troop transportation capability until the modified Round Table-class landing ship was commissioned in 1981.