A $5bn plan to extend the lives of the navy’s Collins-class ­submarines is in disarray as the government-owned shipbuilder ASC warns it won’t be ready to fully upgrade the first boat ...

The plan to upgrade the Collins-class ... conventional boats, so-called military off-the-shelf boats built overseas, as a training force designed to keep a navy submarine capability functioning.

The Defence Minister has acknowledged issues with the already troubled Life Extension program of Australia’s ageing Collins-class submarines. It comes amid a report that the work cannot be done ...