On your benchmark assumption, the Block 4 would have been a better option, it has all the features of the Block 3 but has had a lot of systems redesigned to improve serviceability and reduce operating costs (including increasing the time between major maintenance & thus increasing the number of patrols that each submarine can do in its service life).
I think a smarter option for the RAN is to built standard length Block 6 Virginia’s as they will be in production by the time our processes are complete. The USN will probably build the longer version with the Virginia Payload Module (4 Payload Tubes) but, as that will probably be too much capability for the RAN, the standard ones would save some money. There are some new technologies being tested on the USS South Dakota which are expected to be mature enough to be included in the Block 6 design so this would give the RAN boats the latest technology which would assist in maintaining full capability throughout their life.
Your displacement figures seem to be inaccurate as most articles indicate that the Blocks 1-4 Virginia’s displace 7,900 tons and the longer Block 5 displaces 10,200 tons.
Your point about the cost is very valid and this project will take a large percentage of the ADF’s budget - hopefully not to the point that other important programs suffer.
I understand that there were problems during the AWD build caused by having sections of the ships build at different locations and thus the Defence Department is very reluctant to do that again (despite the political pressure from State governments to create work/jobs for them). If local building of the SSN’s does proceed, I think the plan is to massively increase the submarine building section known as Osborne North to be able to construct all sections (apart from the reactor section) locally. It’s a massive task and attracting enough workers and getting them trained is going to be very difficult. The previous government leased (with the intention of buying if it proceeds) an additional 45 hectares of land adjacent to the current facility so they have the room to expand if the plans come to fruition.
An alternative that has a lot of merit is for the AUKUS nations to jointly develop the next generation of SSN’s. For the RAN to be involved at the beginning of this (replacing the US SSN (X) & UK SSN (R) programs) would mean that the RAN would get the most up to date submarines in the world. The downside would be the extra delay to service entry that would be involved and would require some interim capability in the form of leasing SSN’s (none are currently available) or building long range SSK’s such as a Son-of-Collins incorporating a lot of commonality with the post LOTE Collins class.
Last edited by Going Boeing; 19th September 2022 at 09:18.