The Collins-class submarines are Australian-built diesel-electric submarines operated by the Royal Australian Navy (RAN). The Collins class takes its name from Australian Vice Admiral John Augustine Collins; each of the six submarines is named after significant RAN personnel who distinguished themselves in action during . The six vessels were the first submarines built in Australia, prompting widespread improvements in Australian industry and delivering a sovereign (Australian controlled) sustainment/maintenance capability. Planning for a new design to replace the RAN's submarines began in the late 1970s and early 1980s. Proposals were received from seven companies; two were selected for a funded study to determine the winning design, which was announced in mid-1987. The submarines, enlarged versions of Swedish shipbuilder Kockums' and originally referred to as the Type 471, were constructed between 1990 and 2003 in South Australia by the Australian Submarine Corporation (ASC). The submarines have been the subject of many incidents and technical problems since the design phase, including accusations of foul play and bias during the design selection, improper handling of design changes during construction, major capability deficiencies in the first submarines, and ongoing technical problems throughout the early life of the class. These problems have been compounded by the inability of the RAN to retain sufficient personnel to operate the submarines—by 2008, only three could be manned, and between 2009 and 2012, on average two or fewer were fully operational. The resulting negative press has led to a poor public perception of the Collins class. After 20 years of service issues, the boats have finally provided high availability to the RAN since 2016. The Collins class was expected to be retired about 2026, however, the 2016 Defence White Paper extended this into the 2030s. The Collins class life will now be extended and will receive an unplanned capability upgrade, including sonar and communications. The initial replacement for the Collins class was to be a conventionally-powered version of the Barracuda-class SSN proposed by Naval Group of France, dubbed the . On 15 September 2021, in the face of growing delays and cost increases, the Australian government announced the cancellation of the contract with Naval Group, and that the replacement will be a nuclear-powered submarine fleet made in partnership with the United Kingdom and the United States. Development and design The proposal for a new type of submarine to replace the Oberon class of diesel-electric submarines began in July 1978, when