Is there any merit in looking at a dedicated new LHD with F-35 capability?
I know this has been thrashed about before and is pretty well unlikely but what would be required?
I don't want to open a can of worms and I'm aware of our limitations. This is just hypothetical, of course.
One of the first things it would need would be an enormous amount of funding. The cost in 2007 dollars was ~AUD$1.5 bil. per vessel and now nearly 20 years later would likely approach twice that amount before any modifications or improvements to fast jet ops and handling.
Then the ADF would also need to pay for more F-35's which could then operate from said new vessel, as well as raising all the formations necessary to operate and sustain the new force of F-35's and their support vessel. Additionally, adding such a new, additional and very much high value target would likely then require further expansion of RAN escort forces, requiring yet more funding for the kit and more still to for all the additional personnel.
It is one of those things which, whilst theoretically possible, rapidly becomes quite difficult, time consuming and expensive because it is not just as simple as getting another vessel.
IIRC, the internal fuel load on an F-35B is about six tonnes, so you could get at least an extra day on those figures, though whether you could maintain such a sortie rate for four or five days is a good question in itself. Your point stands. The Canberras are far from ideal for F-35B operations other than for training perhaps.
Read through a few other things and it does appear the F-35B internal fuel capacity is around 6 tonnes, some sources listing just under 6,000 kg of internal fuel and others listing just over 6,000 kg. That might change the rough calc numbers so there is enough fuel for more than five days of sorties by 8 aircraft @3 sorties per day. Better but not IMO a significant difference, never mind the magazine capacity issue.