Collins one of the most capable conventional submarines: Defence

The navy has defended its troubled Collins-class submarines, saying it had to identify properly all of their faults in a report to help determine whether their service life could be extended.

Defence said the Collins remained one of the most capable conventional submarines in the world despite a report, revealed in The Australian this week, that found 68 critical faults that could force the boats into early retirement.

The report by the Defence Materiel Organisation late last year found hopes of extending the life of the six Collins submarines until the 2030s when new submarines could be built would be "unachievable" unless urgent action was taken to fix major systems faults aboard each boat.

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