That reactor uses fuel enriched to <5% and has a refuelling time of 2.5 years. That's completely unsuitable for a nuclear submarine.
09V/09VI (095/096) Nuclear Submarine Thread
- Thread starter Hendrik_2000
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That's because it's a civilian reactor used to generate electricity on a barge.
This one is intriguing to me because it's produced by Bohai shipyard and at a size/power generation that you could theoretically fit in to a nuclear submarine. Looking at this, it makes me wonder if China achieved a certain capability level in mini nuclear reactor technology to be able to put something like this in civilian market. Does this indicate they are now capable of building a 200 MW reactor for submarine?
I’m not an expert so no comment for tech level, but I’m sure the development among ‘generations’ of civilian reactors is more about safety, less about economy and None about volume/power/noise. So it’s a little bit weird for me, just like analyzing LO capability of X-32 but your argument is the range of B-737…
On the other hand, I’m also sure the design of HEU reactor and LEU reactor are different so any similarity of size maybe just by chance. People around the world did a lot of work to transfer HEU reactors to civilian LEU civilian versions, so we do know it’s not easy.
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I got it and can’t agree more. IMO it’s a waste to attack fixed sites in Guam by SSNs but anyway VLS is worth, perhaps the most worth investment.
I would say that for reasons of economics and capability, Chinese SSNs should focus on things that only subs can do, and not on replicating capabilities that other platforms can do, just from underwater. That is because unlike ground forces, surface ships, aircraft and spacecraft, subs cannot communicate large bandwidth data in real time with other units. They can barely even send data at all, only receive.
Subs also have a hard time with long range targeting and self positioning. It is difficult to identify and precisely locate a ship with sonar from 100+ km out while it is trivial with radar or optical sensors.
Subs cannot receive either satellite or land based positioning signals continuously. To locate themselves they use inertial navigation which has compounding errors. They need a satellite comm beacon that surfaces (and is easily visible to aircraft) to communicate 2 way. To receive orders while submerged they can only rely on ELF signals with extremely low bandwidth.
That makes them unsuitable for a highly coordinated effort requiring cooperation with other forces in real time and with constant communication, like a conventional first strike on a highly defended military target in open water.
They're much more suitable for stealthy, low profile missions: short ranged ambushes, mine laying, underwater recon for fixed structures like cables and pipelines.
I'd say, focus on their core capabilities. Mine laying, UUV, torpedo, maybe some tube adapted missiles for flexibility, but no need for a huge VLS farm if it adds more than 20-30% cost.
As for what they can do in improvement to compensate for their weaknesses and focus on their strengths, it'll be things like deploying mines, UUV, submersibles, hydrophones or decoys (things that only subs can do), and long range torpedos utilizing lessons learned from UUV technology to passively propel themselves as far as possible towards a target until the final sprint.
Subs also have a hard time with long range targeting and self positioning. It is difficult to identify and precisely locate a ship with sonar from 100+ km out while it is trivial with radar or optical sensors.
Subs cannot receive either satellite or land based positioning signals continuously. To locate themselves they use inertial navigation which has compounding errors. They need a satellite comm beacon that surfaces (and is easily visible to aircraft) to communicate 2 way. To receive orders while submerged they can only rely on ELF signals with extremely low bandwidth.
That makes them unsuitable for a highly coordinated effort requiring cooperation with other forces in real time and with constant communication, like a conventional first strike on a highly defended military target in open water.
They're much more suitable for stealthy, low profile missions: short ranged ambushes, mine laying, underwater recon for fixed structures like cables and pipelines.
I'd say, focus on their core capabilities. Mine laying, UUV, torpedo, maybe some tube adapted missiles for flexibility, but no need for a huge VLS farm if it adds more than 20-30% cost.
As for what they can do in improvement to compensate for their weaknesses and focus on their strengths, it'll be things like deploying mines, UUV, submersibles, hydrophones or decoys (things that only subs can do), and long range torpedos utilizing lessons learned from UUV technology to passively propel themselves as far as possible towards a target until the final sprint.
In 1993, GAO claimed the communication between headquarters and SSBNs is as fast/reliable as silos. So if they’re only used as launching platforms, communication is not a big deal. The difficult part is to leverage ISR capability of SSNs.
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I was told that KLT40S is very similar to OK-650 reactors used by Akula and Borei class (and even the first Yasen I think). And in this case, ACPR50S seems to just be a more powerful/efficient thank KLT40S (35MWe/150MWt vs 50MWe/200MWt)
OK-900A specifications:
Check slide 25
OK-650 is believed to be a variant of OK900A PWR with support systems rearranged and modified to fit within the submarine hull
Kirov class uses KN-3, which uses an OK-900A variant capable of operating at significantly higher power.
Check slide 26, So both KLT40S and OK-650V have the sam lineage back to OK-900A.
So if China is capable of building a 200MWt ACPR50S, it would seem to me that building a 200+ MWt reactor for submarine should be a given at this point. Given the size of Akula and Yasen class, I think the next Chinese SSN will be huge.
now there’s a trend to build small civilian reactors. there’re many plans around the world but rarely relevant to submarine reactors design. I prefer to treat KLT40S as a Cold War time exception.
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By what mechanism? There's only a few known mechanisms by which to communicate underwater, they're all low bandwidth or short ranged. And communication with SSBNs is much simpler (command to launch at predetermined targets or to release beacon for 2 way comms) than that for SSNs.
We don’t know but ELF is enough to transmit a targeting location in <1min. Its bandwidth is around 1bps.
SSBNs have the ability to retarget underwater by command.