While it a complex technology currently, it is attainable. In addition, we already have the loyal wingman idea, submarine drones and unmanned surface combatants, it is not unreasonable to extend those concepts to submarines. They can be used as loitering munitions with unlimited duration and coverage area in addition to loyal wingmen (aquamen?). If the communication challenges can be overcome, it would be real paradigm shift in how underwater warfare can be waged.
Rumoured "mini-nuke/diesel" Submarine SSK-N(?) thread
- Thread starter ACuriousPLAFan
- Start date
Let's at least wait until conventional UUVs of a large size (>1000t) can be demonstrated, and await this SSKN to emerge (if it does) and prove itself as a viable manned concept first.
Regarding vibration, if one Stirling engine produces linear vibrations then two Stirling engines can work together, in opposite phases, to cancel out each others vibrations. The mini-nuke has 4 Stirling engines, it is possible they are connected in such a way as to produce virtually no vibrations transmitted to the hull.
If this is truly a mini-nuke, it would be a strategic platform. I doubt they'd give us something as classified as engine power before first boat even gets launched. 10MWt delivery 1.2MWe would be 12% efficiency. That is stunningly low. Even 091's reactor going directly into shaft achieved like 18% efficiency.
Again, it's doable, but we have to think about what is the requirement here. Different requirement will lead to different sized propulsion unit.
Let's do some thought experiments here
If PLAN wants this to have real endurance/stealth, then it needs to have atmospheric control machinery, which takes power to operate. 300kw is required to keep lights on for Yuan sub and maybe move occasionally in deep waters. If we add more powerful equipment like atmospheric control, more computation power & sensors, the sub will also be a little larger. Maybe 600kW is needed to keep the lights on at low depth with everything you need and not moving.
Let's say for a 4000t sub, you need 25MWe to move at 30 knots under water (at reasonable depth) (basing this on VA needing 30+MWe to achieve some classified speed). I could be over or under-estimating things here.
To sustain 10 knots, you'd about 1MWe to do so. speed is correlated to power ^ 3
So, you probably need 1.6MWe. Now if we consider eMotor/Drive to be 80% efficient, then we need about 2MWe generated by steam turbine/Stirling to achieve at best 10 knots speed. This is actually better than I thought.
But it rests on my assumptions about speed/power being correct and keeping the lights on calculation to be correct. I could be entirely too optimistic about both here.
Didn't the leak points to a 2500 tons displacement? If true power requirement would be lower than your 4000 tons estimation.
A lot of peeps here is arguing about whether the sub is closer to SSK or SSN, I think it is missing the point. A much smaller sub than 039/040 yet much greater endurance and somewhat improved speed, In gaming terms I think PLAN is going for a new meta here.
The usage of such a system will be much different from SSK or SSN, it enables much different tactics and doctrine for us to pigeon hole it into SSK/SSN. For starter we're looking at a numerous(cheap) and survivable underwater platform that is able to operate in wide and far away areas, what can PLAN do with it?
The AUKUS map uses a 6.5 knot sustained transit speed for a SSK with limited fuel.
But if you plug in 14 knots, that's two-thirds of the SSN speed. Then add in unlimited fuel for the SSKN.
You get a radically different comparison map between an SSN and SSKN.
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For example, a transit distance of 1500nm (2800km) works out as to time on station of:
SSKN: 82%
SSN: 93%
SSK: 62%
This isn't really that significant a difference between an SSKN and SSN.
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Even if you doubled the transit distance to 3000nm (5600km), that works out as to time on station of:
SSKN: 64%
SSN: 86%
SSK: 22% (the SSKN figure is 3x higher)
Even this is still very decent for the SSKN, especially when you consider the difference in cost.
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You can buy somewhere between 3-6 SSKs for the cost of a single SSN, very roughly speaking.
Granted, an SSKN will cost more, but there's likely still a huge cost advantage over an SSN.
And in shallow busy waters, a smaller SSK/SSKN is more suitable and overall a better option than using an SSN.
Yuan class is 3600t. 2500 ton would be a skinny submarine like Song. That's really noisy. You don't even have space to raft that. Let alone provision for long deployment and more space for crew members.
Why would you even believe "leaks" like that?
Generally speaking, larger & wider subs are better, because you can install more noise isolation tech around them.
speed = power ^ 3. If you want to double speed of a boat, you have to 8x the power. Think about that before proposing these things.
Sweden Gotland and Germany 212 are AIP sub arround 1500 tons, they're considered pretty quiet I think? Gotland also uses sterling engine, so I don't see the problem here
they are not that quiet and they have very low endurance (designed to operate in Baltics). The quietest SSKs are also the largest ones like the Japanese ones. Also Chinese subs are typically double hull, so they are naturally going to be bigger
you are also sticking a nuclear reactor in a submarine.