Basic plan: the Australian solution could be 6 x 3,000 ton SSKs to be built 2030-2040 and 6 x 5,000 ton SSNs after 2040. These SSNs may carry small ballistic missiles - the precursor to a nuclear deterrent.
More Detailed Explanation:
If at least 4 Collins hulls (number of deep dives defines submarines that are too "old") can last until 2035 then I think an interim submarine will effectively become the next generation Future Submarine (FSM) which the Government has decided is the Shortfin SSK.
Alternatives to the Shortfin SSK could be 6 SSKs of at least 3,000 ton (surfaced)) with LIBs and maybe AIP, They might best be one of:
- an enlarged (more fuel and batteries, AIP) 3,000 ton Scorpene currently known as SMX 3.0 see
- an enlarged Type 218 (could call it 216) (already has advanced fuel cell AIP)(has time to
- a Soryu Mark 2 or 3 (which would already be developed for LIBs)
The 6 submarines could also utilize highly developed Autonomous Underwater Vehicles to extend capability into the more dangerous (by then China dominated) waters of the South China Sea and near China's future Indian Ocean naval bases.
A submarine tender ship is probably unviable for Western Australia north of Fleet Base West because of the lack of viable ports:
- Exmouth port is only an uneconomic 700nm north of Fleet Base West
- the Port of Darwin, run by a Chinese company, also has a naval base with tide/channel limitations
largely restricting it to small patrol boats and also is only minutes by fast jet or cruise missile from
likely future Chinese air bases in East Timor
After these 6 SSKs are built in Australia it will be 2040 and by then Australia (to have regionally superior subs) will have needed to buy/build 6 SSNs. This is because regional countries (China, India, Russia already have SSNs) and by 2045 North Korea, South Korea and Japan will likely have developed SSNs, likely mounting SLBMs.
So the Australian solution could be 6 x 3,000 ton SSKs to be built 2030-2040 and 6 x 5,000 ton SSNs after 2040. These SSNs may carry small ballistic missiles - the precursor to a nuclear deterrent.
Scale model of the 3,000 tonne concept submarine, SMX 3.0, on display at the DCNS stand, at Euronaval 2016. The SMX 3.0's external shape seems to owe much to the current DCNS 2,000 tonne Scorpene. More details. (Photo courtesy Navy Recognition)