I'm looking at what else the Joint Force needs to do and thinking that the current fleet of P-8s gives us enough for what we do now (if we use them appropriately) and while the extra's make life easier for the P-8 fleet, the missed opportunities are probably greater. Noting #13 - 15 don't actually give us anything new or improved and are effectively continuing a 2015 Joint Force for the next 15 years.
So what would I do? (Disclaimer: I know 3x P-8s cannot fund all the below, bu they could provide seed money, or enough to make them feasible)
Starting just in the maritime domain, there are a few holes I would like to see filled. Being an island, our greatest geographical strength is also our greatest weakness - we rely on the sea, sea lanes and sea transport. To that end, I'd like to boost our persistent surveillance capabilities. P-8's are fine if you know there is a sub or ship there, but are bad at persistent surveillance. So I'd be looking at uncrewed, long-range underwater vehicles, SURTASS ships and a SOSUS network.
@SteveR offers a possible part of that solution
above. The latter is probably of significant diplomatic use, especially at aiding our near neighbours. Why can't there be a G-I-UK gap in SE Asia between Australia, Indonesia, Thailand, Vietnam, Singapore, Malaysia and / or the Philippines? An interlaced, persistent surveillance of our northern approaches from roughly Broome around to Gladstone that reinforces JORN would provide a potent means of directing our MQ-4s and P-8s appropriately, or naval task groups. And - speaking realpolitik wise - supports government efforts around border security
There are opportunities in our mine hunting capability too. It's been ignored by big navy for so long that it's arguable we have a resilient one anymore. I also find it interesting that reports out of some of our allies indicate that modular minehunters don't work, and uncrewed options - while showing promise - don't provide sufficient probability of clearance levels. On top of all this, there are plenty of leftover mines from the 1940s across SE and mid-Asia. Op RENDER SAFE is a significant operations for upholding Australian reputation in these areas, and the MHCs are contributors to that. This ignores all the, often essential and unique, capabilities the hydro offshoot brings regionally. Finally, with only a handful of key ports capable of taking the cargo we need, we need a means of ensuring approaches are kept safe and clear. I'd be looking at replacing our Huon class with another, dedicated and bigger, MHC fleet (not an OPV hull) with uncrewed options that can be run off OPVs to reinforce the MHC work.
Navy workforce....
Long range strike may be an option, noting of course that there are existing projects for such options in ASuW and land operations. But funding more rapid acquisition so that our MFU don't rely on AGM-84 could be useful.
Purchasing actual warstocks of ammunition....
Our sealift, while dramatically better than Timor in 1999, is still insufficient for what Army needs. At the moment we can lift a couple of battlegroups if all three amphib ships are available, with some....limited...ship-to-shore connectors. There has also been some work done by the Sea Power Centre recently that highlights there is no civilian shipping you can "just hire" for contingencies (like many in white and green think). It's all tapped out. So I'd look at investing in a standing contract that can move the rest of the Brigade in one lift and additional ship-to-shore connectors so that we can land more forces on the beach simultaneously.
That's a handful of way's I'd be looking at reinvesting money from 3 extra P-8s into the maritime domain that I think give the Joint Force more than just another 3 P-8s. Beyond that, I'd be looking at:
- AI / machine learning integration
- improved intelligence / PED linkages (focusing on the transfer and analysis of data, not more sensors)
- improved strategic logistics resilience (maybe bringing our logistics chains up to a 1990s standard...)
- pushing our uncrewed platforms that actually contribute in a meaningful way (so not Black Hornet and the like, but brethren of current major platforms to enable the ADF to generate mass better)
That's a quick cut. TLDR - I'd reinvest in ways that improve the Joint Force of 2029, not the Joint Force of 2015