I don't think that the helo gunships are in danger of going the way of the dodo. Yes the current Russo - Ukrainian War is showing battlefield difficulties for them, but lessons will be earned and gunship tactics and strategies will change. War is a dynamic force and you have to evolve or die.
Yup. Those aircraft aren't Apaches either...
What other existing option do you propose for a C130 replacement for the role of battlefield airlifter if it is no longer up to the task?
If the Boeing- Embraer partnership hadn’t fallen apart, the C390 would be an option, still could be if additional risk is acceptable for increased capability.
So you’re thinking 12 C27s and 12 Hercs will become 20 Hercs?
Yes, that is IMHO a possibility. There are only 10 C-27 Spartans in RAAF use.
Not sure about about unpaved runways but likely it can in a manner similar to the C-17, doable but increased risk. As for runway length, probably higher but it is intended to compete with the C-130 so not too much more. The C-2 manages takeoffs at minimum load on 500m and it is larger than the C390. I am guessing the cost of the C-2 eliminated it as an option though.
We need a mixed fleet similar to what we have today but feel the C130 generation should be replaced with something bigger.
From my POV the above does not appear to consider some of the key factors revolving around logistics. Namely the size/volume, and weights to be lifted, and over what distance. IIRC one of the things which had been happening, and part of the reason why the RAAF and before that the US Army was looking at the C-27J Spartan, is that very often a C-130 would be used for an airlift whilst being half empty, because of the distances the load needed to be airlifted. Now something like an A400M can certainly lift a larger sized piece of kit, as well as a heavier one, over a longer distance. However, the RAAF already has the C-17 which can lift more than an A400M. Adding A400M into the mix seems to be an expensive option, unless the ADF has an even greater need to carry outsized loads strategic distances, which the C-17 fleet cannot meet.
And the RAAF hasn't requested a larger aircraft than the C-130, they have asked for more, originally twice as many.
Not at all surprising, given that the full lift capabilities of the C-130 are often not entirely used on missions. Depending on the costs which would be involved in running two tactical airlifter fleets, there might be some justification for getting some CN-235's or C-295's to provide something smaller than the C-130. Otherwise, just keep things simple with a single type.
theaviationist.com
The C-27J is in service with (in penny packets, mostly) or on order by 16 air forces & the USCG, & Leonardo has certainly not ceased support of it, & last I heard, had just introduced a significant avionics update. It 's still in production: Azerbaijan ordered some last month. In the last year a few upgrade contracts have been signed. Support ceased?
The attached article indicates the Aust Army is looking at bringing back a fixed wing capability in the PC12 class. Article behind paywall. Australia seeking to rebuild army's tactical airlift capability (janes.com)
The full article is coming up for that link and I don't have a Janes sub. They are looking at leasing 2 aircraft and are looking at the PC12, Cessna 208B, or the Dahar Kodiak 100/900.
The article mentions the possible aircraft being located at an airfield in SE Qld. That would suggest Oakey, being the AAvn centre and being an Army establishment and not a RAAF airbase (Amberley).