So HMAS Supply is ~175 metres long, HMAS Canberra is 55 meters longer at 230 metres.
According to the Syncrolift website, the lift at Henderson is limited to 150m x 25m x 9.4m with a mass limit of 8,000t. The longest Dry Berth is restricted to 190m length and a width of 24.5m.
Remembering also that ANZAC Class refit work is currently (at least as per Google Maps) carried out in the open air rather then in a covered dock or build hall which is probably not ideal with regards to weather and using mobile cranes rather then overhead gantry cranes.
So at currently Henderson cannot refit a Supply class tanker let alone build one. And the LHD's are significantly bigger again.
The Syncrolift at Osborne *might* be able to lift a Supply class, but would not be able to deal with Canberra.
BAE Henderson
syncrolift.com
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