November 30, 2022

US 2022 China Military Power Report out today: Submarines

The Pentagon’s 2022 China Military Power Report was released today, Nov 29, 2022 (Nov 30 Australian time).

It carries the full name "Military and Security Developments Involving the People's Republic of China". This Congressionally-mandated report serves as an authoritative assessment of the US DoD's pacing challenge and charts the current course of the PRC's military and security strategy.

This follows the DoD’s release of its unclassified National Defense Strategy in October 2022, which "identified the PRC as the most consequential and systemic challenge to U.S. national security and a free and open international system." 

The full 196 page .PDF "2022 China Military Power Report" is HERE.

Major mentions of submarines in it include:

Page XIII - "As the top ship-producing nation in the world by tonnage, the PRC is increasing its shipbuilding capacity and capability for all naval classes: submarines, warships, and auxiliary and amphibious ships. China also has developed underwater systems, publicly revealing a long-range system in 2019 [More on that long range system(s) here and here].

Page 52 – “Submarines. The PLAN has placed a high priority on modernizing its submarine force, but its force structure continues to grow modestly as it works to mature its force, integrate new technologies, and expand its shipyards.

The PLAN currently operates six nuclear-powered ballistic missile submarines (SSBN), six nuclear-powered attack submarines (SSN), and 44 diesel-powered/air-independent powered attack submarines (SS/SSP)

The PLAN will likely maintain between 65 and 70 submarines through the 2020s, replacing older units with more capable units on a near one-to-one basis.

The PRC continues to increase its inventory of conventional submarines capable of firing advanced anti-ship cruise missiles (ASCM). Between the mid-1990s and mid-2000s, the PLAN purchased 12 Russian-built KILO class SS units, eight of which are capable of launching ASCMs. China’s shipyards have delivered 13 SONG class SS units (Type 039) and 17 YUAN class diesel-electric air-independent propulsion attack submarine (SSP) (Type 039A/B). The PRC is expected to produce a total of 25 or more YUAN class submarines by

Page 53 – “2025. In late 2021, the PLAN retired the first two KILO class submarines purchased from Russia in the 1990s. Over the past 15 years, the PLAN has constructed twelve nuclear submarines – two SHANG I class SSNs (Type 093), four SHANG II class SSNs (Type 093A), and six JIN class SSBNs (Type 094). Equipped with the CSS-N-14 (JL-2) submarine-launched ballistic missile (SLBM) (7,200KM), the PLAN’s six operational JIN class SSBNs represent the PRC’s first credible sea-based nuclear deterrent. By the mid-2020s, China will likely build the SHANG class (Type 093B) guided-missile nuclear-powered attack submarine (SSGN). This new SHANG class variant will enhance the PLAN’s anti-surface warfare capability and could provide a clandestine land-attack option if equipped with land-attack cruise missiles (LACM). The PLAN is also improving its antisubmarine warfare (ASW) capabilities through the development of its surface combatants and special mission aircraft, but it continues to lack a robust deep-water ASW capability. By prioritizing the acquisition of ASW capable surface combatants, acoustic surveillance ships, and fixed and rotary wing ASW capable aircraft, the PLAN is significantly improving its ASW capabilities. However, it will still require several years of training and systems integration for the PLAN to develop a robust offensive deep water ASW capability.

Page 54 - Eight of the PLAN’s 10 KILO class SSs are equipped with the Russian built SS-N-27b [Kalibr] ASCM (120NM, 220KM). The PRC’s SONG class SS, YUAN class SSP, and SHANG class SSN field the PLAN’s newest domestic submarine launched YJ-18 and its variants, which constitute an improvement over the SS-N-27b ASCM… As the PLAN continues to transition into a global multi-mission force, the addition of landattack capabilities to its modern array of anti-surface and anti-air capabilities is a logical next step. 

In the coming years, the PLAN will probably field LACMs on its newer cruisers and destroyers and developmental SHANG class Type 093B SSGN. The PLAN could also retrofit its older surface combatants and submarines with land-attack capabilities as well. The addition of land-attack capabilities to the PLAN’s surface combatants and submarines would provide the PLA with flexible long-range strike options. This would allow the PRC to hold land targets at risk beyond the Indo-Pacific region. 

Page 94 – “The PRC is conducting continuous at-sea deterrence patrols with its six JIN-class (Type 094) submarines (SSBNs), which are equipped to carry up to 12 JL-2 or JL-3 SLBMs.”

Page 96 – “Sea-based Platforms. The PRC likely began near-continuous at-sea deterrence patrols with its six operational JIN class SSBNs, which are equipped to carry up to 12 CSS-N-14 (JL-2) or CSS-NX-20 (JL-3) SLBMs.

The PRC’s next-generation Type 096 SSBN is probably intended to field MIRVed SLBMs judging from past developmental trends. The 096 SSBNs will likely begin construction in the early-2020s. Based on the 30-plus-year service life of the PRC’s first generation SSNs, the PRC will operate its [Type 094JIN and Type 096 SSBN fleets concurrently.

The current range limitations of the JL-2 will require the JIN to operate in areas north and east of Hawaii if the PRC seeks to target the east coast of the United States. The fielding of newer, more capable, and longer ranged SLBMs such as the JL-3 gives the PLAN the ability to target the continental United States from littoral waters allowing the PLAN to consider bastion operations to enhance the survivability of its sea-based deterrent. The South China Sea and Bohai Gulf are probably the PRC’s preferred options for employing this concept.

Page 166 – see “Taiwan Strait Military Balance, Naval Forces” table, which includes submarines [heavily in China’s favour]

[As I can't convert .PDF to .html below is last year's table, courtesy Econbrowser. Until the 2022 Table is available in .html].

November 28, 2022

Future Dutch Submarine RFQ: "3,200 tonnes"

Submarine Matters has been monitoring the Netherlands' Future Dutch Submarines (aka Walrus-class submarine replacement) process since 2015.

All credit to a (likely) Dutchman (codename “Kevin”) and more recently non-Dutch /Kjell for describing the Netherlands submarine needs and the replacement process. See this overview of the process.

On November 16, 2022 Netherlands Ministry of Defense Press Release (reproduced by Naval News) indicated:

Today, as previously discussed with the House, the Ministry of Defense has [issued a Request for Quotations (RFQ)] for 4 new submarines from 3 candidate shipyards. The candidate yards are Naval Group , Saab Kockums and ThyssenKrupp Marine Systems. They are expected to submit their bids around the [northern summer - June to August] 2023.

Defense then needs a number of months to analyse the detailed bids. Based on predetermined requirements and award criteria, the Ministry of Defense decides which yard is allowed to build the boats. One of the award criteria is the participation of Dutch companies in the development, construction and maintenance of important systems of the boat. Defense also wants as much Dutch involvement as possible to strengthen the technological and industrial base. The winning yard must sign an agreement for this with the Ministry of Economic Affairs and Climate Policy.”

++++++++++++

On November 27, 2022 /Kjell identified the Naval News Youtubes, with the intrepid Xavier Vavasseur, interviewing the 3 bidders and Dutch DMO to the extent possible, including:

Naval Group - Around Nov 24, 2022 “Naval Group's Conventional Barracuda” 1:25 maybe pumpjet, benefitting from France’s Barracuda SSN [and maybe Attack-class  SSK] programs. Mediterranean, Caribbean seas, Atlantic, Indian oceans, seabed capable. All quieting technologies included https://youtu.be/B3Agdn7_CJA

SAAB Damen - Around Nov 24, 2022 “Saab C71 Submarine (based on A26)” Offering Multi-mission Portal, UK Sonars offered. Can have modular extensions, Dutch technical/maintenance autonomy important. https://youtu.be/oaRwYfxRpJA

TKMS - Youtube around Nov 25, 2022 “Type 212CD E” ie. the 212 Common Design, Extended Range sufficient to transit Netherlands to Dutch Caribbean several weeks on station, then transit back. Maybe 3,200 tonnes submerged. At 1:40 what look like 10 vertical launch doors are apparent https://youtu.be/91OaZFdprTY

Dutch DMO Requirements - Youtube around Nov 23, 2022 “Dutch Naval Programs at NEDS 2022: Submarines” Dutch Admiral (Director Defense Materiel Organisation (DMO)) saying new subs will need to have all capabilities of the Walrus class [implicitly range, so same/more diesel fuel, so higher displacement likely] https://youtu.be/vj_oFLqsfww . Portion on subs is at 1:40 to 7:10.

++++++++++++

The Nov 16, 2022 Press Release was foreshadowed in an earlier, September 30, 2022 Netherlands Ministry of Defense Press Release https://www.defensie.nl/actueel/nieuws/2022/09/30/belangrijke-mijlpaal-vervanging-onderzeeboten-offerteaanvraag-gereed indicating ability to carry “long range missiles” is a requirement.

+++++++++++++

Pete Comment

It is unknown whether the Dutch Navy requires Lithium-ion Batteries (LIBs) and/or AIP for the future subs. Some past commenters have considered Naval Group and TKMS less likely winners because the Dutch don’t like being dominated by these large neighbours. Then again, having lost the Australian order Naval Group’s SSK Division might be very hungry – thus maybe offering the lowest price. But who knows?!

November 27, 2022

SONARS and POWER USAGE

Where "C" wrote on Nov 25, 2022 "I'm no sonar engineer, but I'm still baffled why a sonar system in passive mode would consume upwards of 75Kw - active is different for sure - those are BIG numbers."

I'm also no sound engineer, but I would say:

A passive sonar uses a lot of power to amplify very weak sounds and for massive processing of signal tasks to make sense of sounds, esoecially identifying the precise source. See what Aaron describes in 2 below.

SSKs and SSNs (all attack subs) are more famous users of spherical active and passive sonar uses for ASW and anti-ship work.

However attack subs also use very weak, discrete beam, active/passive navigation/movement sonar pulses to image the seafloor, seamounts and other obstructions that the sub would otherwise risk banging into. Again these are very weak pulses undetectable by enemy sonars/seafloor hydrophones but are received on a constant basis by the sub's active/passive bow sonar.

1. On what happens when this imaging system doesn't work or isn't efficiently used see my November 2021 reporting on the Seawolf class sub USS Connecticut's major accident hitting a seamount:

1A - here https://gentleseas.blogspot.com/2021/11/us-sub-did-hit-seabed-projecting.html

1B - especially the diagram here https://gentleseas.blogspot.com/2021/11/uss-connecticuts-sonar-navigation-wasnt.html

2 Aaron, former USN Los Angeles class SSN and Ohio class SSBN Sonarman,  does discuss how sonars/sonarmen work in detail here and on his "Sub Brief" Youtube website https://www.youtube.com/c/subbrief

Aaron's (aka Jive Turkey's) description is interesting:

2A - 2min45secs into "The Ping" https://youtu.be/24uLeEKma5g It sounds like Aaron was using a great deal of energy for his Active (anti-sub or surface ship) "Ping".

2B - 20min into "USS Connecticut South China Sea Collision" https://youtu.be/5VKQPBhu0z0  eg. avoid collision "tools...that they will not make public" which Pete suspects is navigation sonar mode.

A Seawolf-class bow sonar arrangement (photo courtesy USN via The Drive 2020.)
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2C - 1:36 into "USS Connecticut Damage Update..." https://youtu.be/vB-eSTpvKgs shows what I think is the half spherical active sonar - it is so positioned (mainly downward) to send weak navigation pulses, picked up by the much larger spherical passive sonar. (photo above)

So much for us all to learn on the edges of guesswork.

November 26, 2022

AUKUS SSNs "could cost A$10 Billion each"

In an exclusive Andrew Tillett for the Australian Financial Review (AFR), on November 25, 2022, reports a whole range of new (possible) issues titled:

Warning that nuclear submarines could cost $10b each

November 24, 2022

"C" on Submarine Hotel Load Power Uses & Amounts

“C” on Nov 23, 2022 made a long comment on submarine hotel load power uses.

It’s a comment well worth turning into the following article:

"Replying to Anonymous's very interesting response [of Nov 16, 2022 here]  to my Hotel load point: the comment from Fleet Command Kobayashi [scroll down here for his photo and bio] is revealing and useful in confirming my suspicion that submarine commanders are likely judicious in what systems they run during endurance exercises.

I would add that the Thales VELOX-M8 Intercept Sonar example I gave (which is one of the very few examples I have found in literature where the vendor has given a power value) was 400W, or 0.4Kw, which is not a lot in the bigger picture of hotel load computations, which seem to waffle between 50 and 200 KWh. This is an intercept sonar, ie. a relatively small item of kit, an adjunct auxiliary to the primary arrays mainly used for classifying a received tone (sound electronic support measures (ESM) [intelligence gathering] essentially). The processing unit takes up about 6U of rack-space, and I'm not sure the array size, but intercept sonars are typically very small, the British type 2019 "nipple" being iconic [scroll half way down the very informative "The History Of British Submarine Sonars" for "SONAR TYPE 2019 DOME"].

Nonetheless the point that designers actively have tilted away from certain system layouts typical in nuke boats because of power consumption is good to have confirmed.

Here's my extremely rough cut of load for a medium-large boat with a crew of c. 60, and these are, in my view, very generous:

ENVIRONMENT

12KW for Heating, ventilation, and air conditioning (HVAC) (rough guide of 5 people per KW)

1KW for lighting (incandescent lighting should be long gone, LED's are so vastly superior in sub context its not funny)

FOOD

3Kw for refrigeration (A 30 cubic-meter cold room will draw about this)

5Kw for food preparation (this will flux according to usage, but this will power an oven an 4 hot plates at full tilt, but I use this number as an "average")

2Kw for misc (kettles/boilers etc, also an average as will flux)

OPERATIONAL TECHNOLOGY (OT)

This is trickier and depends on degree of automation on board, I work in Mining OT space so by way of comparison, all the OT control systems of a large processing mill, with around 250 devices draws, for CONTROL purposes, between 2 and 8 Kw, depending on how many things are in state-change at any point in time. This feels a reasonable starting point, so...

6KW for onboard OT. (eg. raising a mast will require a controller that draws only a few watts constantly, but the actual Variable speed drive (VSD) which is driven by it, that does the actual hoist, will draw mush more for the few seconds its working)

SONAR, COMBAT, COMMUNICATIONS, ETC

Well this is the big hole. I don’t know. So far everything else has come in at about 30KW, which, if numbers like 100KW for hotel are taken, leaves a ball-aching 70KW in mostly computational activity. Its plausible, but thats roughly equivalent to around 100 mainstream IT servers, which feels excessive. Each terminal station, if it includes a pair or large LCD screens, networking and computation will likely draw 0.5 to 1KW, so a boat with 8 such terminals means there is 8KW up front.

I welcome adjustments/insights/amendments to this, as at the moment its just not adding up, unless current systems are just woefully inefficient and using 90's era or older systems - which may very well be the case.

C”

Pete Comment

For further reading relevant to submarine propulsion and non-propulsion (hotel load) electrical uses see Marine Insight's "Different Systems on a Naval Submarine" of April 17, 2021 at https://www.marineinsight.com/naval-architecture/different-systems-on-a-naval-submarine/

November 23, 2022

AUKUS SSNs With Nuclear Weapons

I’ve long argued that its of little use Australia has SSNs as a China deterrent. 

This is if our SSNs are merely armed with torpedoes, Harpoon and/or Tomahawk subsonic SLCMs and mines. These would only add up to a total “throw weight” of 25 tonnes of high explosive, maximum. Land attacking China merely with high explosive, subsonic, SLCMs would result in many/most being shot down, fail to deter China, but just make China more angry.

Australian SSNs need sufficient vertical tube versatility to be armed with hypersonic missiles of various sizes, or even ballistic missiles.

So it is by good fortune that the US SSN(X) debate is publicly leaning (on Nov 10, 2022) towards larger (therefore more costly) 9,000 tonne Seawolf sized SSNs/SSGNs. The Seawolf Mark I’s beam/diameter is 12m permitting a longer/taller missile than the Virginia’s diameter of 10m.

Hypersonic Missiles on Block V Virginias & SSN(X)/Seawolf Mark IIs

There appear to be plans to deploy Hypersonic Missiles on Block V Virginia SSNs and presumably on not yet diameter designated SSN(X)/Seawolf Mark IIs (but likely of 12m-13m diameter).

Looking at USNI News (Nov 3, 2022) it seems the USN sees it possible that 3 x  Common Hypersonic Glide Bodies (C-HGB) and their boosters could fit in each of 4 Virginia Payload Tubes (VPTs) of 2.2m diameter, behind the sail, by 2029. That is 12 x C-HGBs per Virginia, Block V (the first being USS Oklahoma (SSN-802)).

As hypersonic submarine cruise missiles are new weapon categories under development there is no concrete doctrine (yet) as to whether they can be assumed to have conventional or nuclear warheads.

Meanwhile, the 2 VPTs in front of the Block V's sail may not have the versatility/position to be lengthened - so may be still restricted to subsonic Tomahawk SLCMs.

SSN(X)/Seawolf Mark IIs Capable of Taking 4 Trident IIs?

The 2.2m diameter of VPTs originated from the 2.2m diameter of the originally Trident II silos on the 4 Ohio-class that became SSGNs. Those silos were then converted to each take 7 x Tomahawk missiles. The 7 Tomahawk accommodating diameter was then carried over as VPTs to Virginias.

It is highly likely the VPT will be carried over to the SSN(X)/Seawolf Mark II.

So Trident II SLBMs, at 2.11m diameter, can horizontally fit into a 2.2m Virginia Payload Tube (VPT), but not vertically (yet). 

But vertically? Where I'm going with this is if a Seawolf Mark I’s hull diameter of 12m is only increased by 1m for an SSN(X)/Seawolf Mark II that would make a diameter of 13m.

13m just happens to be the diameter of an Ohio SSBN and planned 13m diameter of a future Columbia SSBN. These, of course, can/will vertically fit a Trident II’s 13.58m height owing to their slight hump.

This would give SSN(X)/Seawolf Mark IIs of 13m diameter and with 4 VPTs the capability to accommodate 4 x Trident IIs.

This might be a future capability much valued by Australia - if its 8 future SSNs happened to be US SSN(X)/Seawolf Mark IIs. Fear of China has made possible the unprecedented AUKUS SSN offer. Increasing fear of China (say, in 2030) may swing the Australian public in favour of an Australian nuclear deterrent.

If Australia chooses the UK, perhaps UK SSN(R)s might have the same SSN(X)  (aka common AUKUS) dimensions enabling a Trident II capability.

This thought should not be confused with the nuclear armed Tomahawk TLAM-N debate. Tomahawks, against a nuclear armed enemy, carry with them the "is it carrying a conventional or nuclear warhead"  ambiguity-misunderstanding. There is no such ambiguity-misunderstanding with SLBMs as they are always assumed to be a nuclear tipped deterrent.

November 22, 2022

Huge Problem Nuclear Qualifying RAN: Report

Australia’s Nautilus Institute has produced a very up to date “Peace and Security Special Report”:

Titled “AUSTRALIA’S FUTURE SUBMARINES: AN EXPLAINER”

By Allan Behm, Rear Admiral Peter Briggs (Retired) and Commodore Paul Greenfield (Retired)

Dated November 16, 2022

At https://mailchi.mp/nautilus/napsnet-special-reportaustralias-future-submarinesan-explainer?e=1a4f758957

Its 33 pages contain a wealth of knowledge, that former senior naval officers are best placed to provide, about Australia’s submarine needs.

At the moment I’m focusing on the main section on nuclear propulsion, which states in part:

“Nuclear reactors also radically change the power available to submarines, their endurance underwater, the transit times and time on station, as well as the “hotel” services available to submarines and their crews. Combat system capability, habitability, air quality, water availability and general amenity are much enhanced. There is much to be said for nuclear propulsion, especially when the submarine’s survivability and that of its crew is taken into account. The cost multiplier, however, may not match the force multiplier effects.

Nuclear propulsion would also raise a host of new and imponderable issues for Australian industry, and for the RAN’s ability to support the submarine. Lacking a nuclear industry—and thus the education and associated skills streams that support such an industry—Australia would necessarily have to develop the education, infrastructure and industrial support needed to maintain the capability as part of the cost of that program. It would be important that Australia develop a sovereign capability in all these areas, as the availability of third parties in a time of tension is moot.

At present, the Royal Australian Navy (RAN) has no nuclear qualified personnel. The nuclear-powered attack submarines (SSNs) and the ballistic missile submarines (SSBNs) in service with the USN and the Royal Navy require between 40 and 50 crew members qualified at varying levels of nuclear expertise per boat, with considerable numbers of similar personnel in the logistics and support functions ashore. Maintaining the pipeline of nuclear-trained personnel in the US or the UK will be costly—approximately $1 million per person per year. Establishing and maintaining a similar pipeline in Australia will not be significantly less expensive.

In June 2022, the US House of Representatives introduced legislation that would assist the RAN to train its future submarine operators in the US: the Australia-US Submarine Officer Pipeline Act will permit at least two Australians to train in the US each year.[15] This is an important, but ultimately token, effort. The pipeline will need to be as wide as it is long to remediate the shortfall in the RAN’s skill base.

It is important to recall that the UK and USA established their SSN capabilities in the circumstances of the Cold War, drawing upon a large force of conventionally powered submarines and steam powered surface ships. This situation assisted in providing the essential manpower and skills base. Nonetheless, the task was a serious challenge for each navy.

Australia has none of these resources and will have to draw heavily on the supplier navy’s training system and seagoing submarine force to train its personnel. The availability of the necessary level of support would be a major risk for an Australian SSN program, and one that needs early resolution.

Equally importantly, the numbers and skillsets in an SSN crew are significantly different to that of a Collins crew. The training program would entail converting existing RAN submarine personnel and a substantial initial training program. Both would require long periods of training and overseas service to gain the necessary experience. Until Australia’s SSN force reached sufficient operational submarines to undertake the at sea training of trainees (say, at least six SSN) most of this training would have to be conducted overseas - and it would take about 20 years to deliver this number of SSNs after initiating the program.

At this point, RAN schools and a nuclear engineering faculty established within a selected Australian tertiary institution could finally begin to take over this task. But in the absence of any nuclear power generation industry in Australia, the cost of establishing and operating this training infrastructure would be borne by the SSN program.

The problem is enormous.”

November 21, 2022

Japanese hypersonic cruise & glide missile progress

Below is an interesting wispywood2344 comment of November 13, 2022:

[Since the October 10, 2022 article] there has been a follow-up report [1] on the news of Japanese long-range missiles. 

According to this report, both the "hypersonic cruise missile (HCM)" and the "highspeed glide missile (HGM) for island defense Block 2" have a range of over 1,000 km. 

This is the first time that the range of a HCM has been reported. 

The range of the HGM was said to be 500 km [2] but this is apparently the range of the "rapidly-deployable" Block 1.

Block 1's range of 500 km realizes "inter-island" firing from Okinawa main island to the entire Nansei islands, but is not enough to cover the Taiwan Strait.

Block 2's range of 1,000+ km will not only realizes "island-to-mainland" firing, i.e., from Okinawa main island to the west coast of the Taiwan strait, but also "inter-mainland" firing, i.e. from Kyushu to Shanghai. 

[1] Sankei-Shimbun (newspaper), "[Exclusive] The Japanese MoD considers to procure 1,500 long-range [hypersonic cruise missiles (HCM)] within 10 years" dated November 6, 2022 [In Japanese. Just right click mouse to translate]. https://www.sankei.com/article/20221106-WRI5DOYKCJMM7FMDMB3LY53IQI/

[2] Mainichi-Shimbun (newspaper), "The Japanese MoD considers installing an anti-aircraft-carrier warhead on the highspeed glide missiles (HGMs) for island defense, as well as increasing their speed and range". dated February 25, 2020. [In Japanese. Just right click mouse to translate. Glide missiles of this type generally reach hypersonic speed. See diagram below]. https://mainichi.jp/articles/20200224/k00/00m/010/219000c


Diagram courtesy Mainichi-Shimbun February 25, 2020.
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November 20, 2022

China's Longer Range JL-3s Allegedly on Type 094 SSBNs

China allegedly has longer range JL-3s on its six Type 094 (NATO designation Jin class) SSBNs. This is according to former naval aviator US Admiral Sam Paparo (Commander US Pacific Fleet) in the Japan Times, November 19, 2022.

Pete Comment

Other sources indicate at least one Type 094 has been modified (as a prototype fitout) to take the JL-3. The JL-3 might be slightly taller and of greater diameter, than already 13m JL-2s. If diameter has been increased then the hitherto 12 silo 094 might have experienced a reduction from 12 x JL-2s to 10 x JL-3s. Other 094s are being considered for similar JL-3 modifications. But full deployment, with 12 to 16 x JL-3s, will likely need to await completion of the Type 096s.

The JL-3 SLBM may have a range of 10,000-12,000km (average to lighter payloads) allowing 094s, in the Chinese protected South China Sea, to hit some of the continental US and all of Australia.

Geography and reputed noisiness of 094s (part owing to their pronounced hump - photo below) restrict them to operating in their near China coast bastions

If they could operate from a captured Taiwan, then quieter, future (13m beam, slightly humped) Type 096s might be able to operate in the mid Pacific - a launch area that could take in all of the continental US.

(Likely Type 094 photo. Courtesy US Government, 2014)
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November 19, 2022

France not offering Australia SSNs, only SSKs.

Unfortunately France at the highest level (President Macron) is criticising Australia’s plans to buy SSNs, as Macron claims this risks increasing tensions with China. See the Australian Financial Review's November 18, 2022 report or, if paywalled, see this report.

This means France is not offering Australia SSNs, only SSKs. 

This is specifically indicated by a France 24 report of November 17, 2022 where President Macron "said France would not supply nuclear submarines to foreign countries, so the offer related only to conventional vessels. 

[President Macron] added it would guarantee Canberra's "freedom and sovereignty", noting that construction would be in Australia."



November 18, 2022

Comments on Nov 11 & 17 articles. Sonars.

Anonymouses "Japanese Submarine LIB distributions & other calculations" of Nov 11, 2022 generated many comments. 

Those are the comments not incorporated into the much better "REVISED Japanese Sub LIB distributions, Othercalculations" which has excellent diagrams, and is dated Nov 17, 2022.  

Those great comments are below and were made between November 12 & 16, 2022:  

"I'm a different Anonymous commented Nov 12, 2022:

A power load for propulsion of 50 kW is far too low for a 3,000 tonne submarine [like a Japanese Taigei or Soryu MK. II]. 50 kW being more like the power of an Outboard engine for a small amateur fishing boat or probably the power needed for a submarine to barely stay idle in a current.

This is noting the Kuroshio current in the Tsushima Strait is above 5 knots. 300 kW is probably the minimum for a sub, necessary to reach 5 knots.

A simple back of the envelope calculation considering the public data (eg. French Jeumont engines):

-  on the 2,000 tonne S-Br (Brazilian Navy Scorpene) where 2,900 kW is needed to sprint at 20 knots submerged

-  on the Barracuda/Suffren class SSN (5,000 tonnes) where 15,000 kW is needed to reach 28 knots

On the lower length/diameter L/D Taigei at 3,000 tonne, (the power need evolves as the square of the speed) this rule of thumb will lead to 300+ kW at 5 knots. This would mean a week in a real tactical situation which is remarkable

More important is the power density, the shape of the discharge /charge curve and the charging speed (under snorkel) to decrese the indiscretion ratio.

++++++++++++++ 

wispywood2344 commented Nov 13, 2022:

There is a serious clue about the energy capacity of Japanese submarine LIB "SLH" hidden in a document published on the Web by the Japanese MoD.

This is it. [1]

It should look familiar to you.

Display the graph on the page 2 of this document and enter "Ctrl+A," you can reveal the HIDDEN (or FAILED TO BE DELETED) LETTERS on the vertical axis. [2]

Therefore, we can assert that the capacity of a lithium-ion cell used in "SLH" is 1000-2500 Ah.

Since "SLH" uses LCO as the positive electrode material and carbon as the negative electrode [3], the nominal voltage of a "SLH" module is around 37V.

Taken together, the energy capacity of "SLH" can be estimated to be around 36-93 kWh per module. 

[1] FY2006 Post project evaluation "Development of new submarine main battery"

https://warp.da.ndl.go.jp/info:ndljp/pid/11339364/www.mod.go.jp/j/approach/hyouka/seisaku/results/18/jigo/sankou/jigo05_sankou.pdf#page=2

[2]  http://blog.livedoor.jp/wispywood2344/others/SLH_Capacity_Leakage.gif

[3] "Realization of the world's first submarine equipped with a lithium-ion battery system", at Defense structure improvement foundation at https://ssl.bsk-z.or.jp/kenkyucenter/pdf/gyt20201210.pdf#page=2

+++++++++++++ 

An Anonymous commented Nov 14, 2022:

Once, an influential politician on Japanese MoD revealed there was an improved version (SLH2?) of the current lithium-ion battery (=SLH) for submarine, but due to budget constraints, the improved version could not be obtained. 

So, SLH2 might be based on is based on high performance lithium-ion battery for space (energy density 168Wh/kg), while SLH might be based on is based on large lithium-ion battery for space (energy density 140Wh/kg).

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SONARS are High Hotel Load Users

C commented Nov 14, 2022:

I think rather a lot hinges on the hotel load. I read all sorts of numbers from 50 to 200Kwh, but its all very iffy and vague.

My point is that is in all my reading the composition of hotel-load is glossed over, but maybe its worth some drilling down into this? eg: The Thales VELOX-M8 Broadband Sonar Interceptor [Control-F for "sonar" within this Barracuda SSN link] uses up to 400W when running (which I suspect is a max number). One could put some fair estimates on air circulation systems based on industrial HVAC. Ditto for refrigeration. Etc.

I confess I cant really contribute very much to this, I have snippets only, but I think its critical in understanding practical endurance for modern boats - if designers were able to halve the hotel load, they'd double endurance!

eg. There is also the issue that any computational system that generates waste heat, will also need that heat removed, essentially doubling the energy cost (this is the classic cost issue with massive datacenters), ergo a BIG incentive to use highly efficient [digital signal processors] DSPs, [central processing units] CPUs, etc. I suspect most of the big sonar rigs designed by nuclear sub club countries are not overly concerned with power consumption (obviously), but other vendors may (or may not) be far more judicious.

Something to chew on.

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Another Anonymous commented Nov 16, 2022:

The French SSN, Barracuda-class submarine is equipped with the Thales VELOX-M8 intercept sonar [1]. But, a conventional submarine with limited power supply cannot be equipped with this kind of high power consumption sonar [2] and is equipped with low power consumption and less sensitive sonar instead. 

[1] Barracuda SSN Specs: at Very long link :   

[2] SHIPS OF THE WORLD, Special issue 159, page 21, by Ex-Fleet Commander of JMSDF [Japanese Navy] Masao Kobayashi. [scroll down here for his photo and biodata.] Kobayashi said:

“In order to maintain long-term diving, it is essential to reduce the hotel load, and it is necessary to reduce the power consumption of the onboard equipment. This makes a great impact on the onboard equipment. For example, the [Virginia sub's BQQ-10 spherical bow sonar array] generates a uniform sonar beam toward not only in a right and left direction but also in an up and down direction and is very effective. But there is no conventional submarine equipped with the spherical array because the beam generation of this array needs a huge amount of calculations, i.e., huge power consumption.”

November 17, 2022

REVISED Japanese Sub LIB distributions, Other calculations

Anonymous has provided much improved revisions of article:

 

Below are very simplified diagrams of Japanese subs with the estimated number and distribution of Lithium-ion Battery (LIB) modules in yellow


All this highlights the advantages of the Japanese all LIB Taigei-class subs over the 50 tonne lighter all LIB Soryu Mark (MK) IIs (namely JS Oryu and JS Toryu). The LIB distribution

 

 

Propulsion Motor

 

Diesel

Officer

Command

Command

 

Torpedo

 

Bow Sonar

LIBs a

Crew/eating

Mechanical

LIBs

LIBs

LIBs

b

c

d

 

Figure 1. Schematic structure of Toryu/Oryu (Soryu MK IIs)

 

-  5 Bulkheads: Propulsion Motor/Diesel/LIBs(ab)/LIBs(c)/LIBs(d)/Torpedo Room 

-  Double hull: Propulsion Motor, Diesel, Torpedo Rms

-   Single hull: Other Rooms except bow sonar

-  Number LIBs = 640 = 80 (a) + 80 (b) + 240 (c) + 240 (d)-  Higher center of gravity due to 80 LIBs in higher LIBs "a" section - 

-  Higher center of gravity due to 80 LIBs in higher LIBs "a" section

-  LIBs in "a" section increases vertical stray magnetic problems.

-  Stray fields can be more easily electro-magnetically detected by ASW enemies. Strays fields can also upset -  delicate electronic equipment in the submarine.

-  Regarding "Fuel/Water" (omitted from Figures 1. and 2.) once the Diesel Fuel is consumed the fuel tank is filled with seawater to maintain constant weight distribution (important for buoyancy and trim)

 

 

Propulsion

 

Diesel

Officer

Command

 

Torpedo

 

Sonar

Crew/eating

Mechanical

LIBs

LIBs

LIBs

LIBs

LIBs

LIBs

A

B

C

D

E

F

 

Figure 2. Schematic structure of Taigeis - much improved from Toryu/Oryu (Soryu MK IIs)

 

Greater number of LIBs for longer full submergence / more discrete = 720 LIB modules = 120 x 6 in each of (A, B, C, D, E & F) sections
-  Less vertical
 stray magnetic fields
-  Lower center of gravity, better for calculating and maintaining buoyancy and trim.
-  Less potential leakage of dangerous gases caused by fire from battery sections to upper sections.

-  Easier to deploy downward traveling fire suppressant gases as all batteries are contained in bottom deck of a Taigei.

- Fewer Bulkheads: maybe as low as 4 ie. Propulsion Motor/Diesel / LIBs (ABC) /LIBs (DEF) / Torpedo rooms.

Based on official report of Japanese MoD information, a decrease in numbers of bulkheads was estimated to be four in Taigei-class submarines [5-7], while numbers of bulkheads in Soryu MK Is and IIs are five.

[5] Study on structural type of submarine by MoD (FY2012)

Implementation plan (completed): FY2013-2015 (budget implementation 554 million yen) Prototyping (by MHI) , FY2014-2015 (budget implementation 504 million yen) Laboratory testing (by MHI)

Needs (excerpt): Elongation of the compartment based on the new structural type of submarine is needed to contribute to the rational installation of the equipment inside of submarine.. 

[6] If length of submarine does not change, “elongation of compartment” may suggest decrease in numbers of bulkhead. 

[7] Taigei was laid down in 2018, and its length is as same as Soryu.

 

 

                                                  Stern                                                                          Bow

+-

+-

+-

+-

+-

+-

+-

+-

+-

+-

-+

-+

-+

-+

-+

-+

-+

-+

-+

-+

 

Figure 3. Top views of  series connection (from bow to stern) of 20LIB modules in Oryu/Toryu/Taigeis.

 

Size of 20 LIB-modules 444cm[D]  x  83.2cm[W] x 166.7cm[H] or  431m[D] x  88.8cm[W] x 166.7cm[H] 

 

 

Stern                  Bow

20LIB-modules

20LIB-modules

20LIB-modules

20LIB-modules

 

Fig 4a. Top view of 20 LIB-modules in Oryu/Toryu (a and b in Figure 1)

 

Stern------------ Bow

20LIB-modules

20LIB-modules

20LIB-modules

20LIB-modules

20LIB-modules

20LIB-modules

 

Fig 4b. Top view of 20 LIB-modules in Ouryu/Toryu/Taigei  (c/d in Figure 1, A-F in Figure 2)

 

Soryu MK. I has two lead acid batteries [LAB: 444mm(D), 432mm(W), 1665m(H), 880kg, 2V] sections [c and d in Figure 1]. In each battery section, 240 LAB modules are connected in series generating 480V (=2V x 240).

Two battery sections are connected in parallel (480V).

 

In Oryu/Toryu/Taigeis, 20 LIB-modules [each, 444mm(D),431mm(W),1667mm(H),770(kg), 36V] (Figures 3, 4) are connected from bow to stern in series generating 720V (=36V x 20), where 20 LIB-modules seem to be folded in two (10 LIB modules x 2) to cancel stray magnetic field from bow to stern. All 20 LIB-modules are connected in parallel (720V).

 

Battery arrangements of LABs (c/d in Fig1, Soryu MK. I) and LIBs (c/d in Fig 1. Soryu MK. II, A-F in Fig 2. Taigei) should be the same because they install batteries with the same dimensions and weight. Their arrangement is according to multiples of 3, 2 and 5. But, 80 LIBs are arranged in c/d of Oryu/Toryu, and their arrangement is according to multiples of 2 and 5. Then, series connection of LIB module is based on multiples of 2 and 5 and minimize stray magnetic field. Possible arrangements are 10 LIBs (360V) and 20 LIBs (720), higher voltage (720V) is electrically more efficient.

 

Anonymous on November 8, 2022 provided extra calculations, which are reproduced below:


Energy of total Japanese submarine LIBs (codenamed “SLHs”) is estimated to be 62-74MWh and 70-83MWh for Oryu/Toryu (ie. The Soryu Mk IIs) and the Taigeis, respectively. This suggests maximum fully submerged endurance of 9-11 days and 10-12 days respectively [3].

 

Calculations:

 

[1] https://www.gs-yuasa.com/gyt/jp/products/space/ [Japanese doc . Just right-click mouse to Translate to English.] High performance lithium-ion battery for spacecraft (eg. satellites and “space probes”): energy density 168Wh/kg, 130(Width) x 50(Depth) x 271(Height) all in mm

Energy density of this battery is ca.20% higher than [2] suggesting energy density of [2] is 140Wh/kg.

 

[2] https://www.gs-yuasa.com/gyt/jp/products/lithium_l.php [Japanese doc . Just right-click mouse to Translate to English.]

Large lithium-ion battery for space: energy density 140Wh/kg

 

[3] Estimated energy of submarine (Oryu/Toryu, Taigeis) with SLH (weight 770kg) based on [1] and [2].  If 10% of SLH is used for "frame" [does this mean for internal battery function, eg. keeping battery warm enough to be efficient?] and so on, then energy of SLH is 0.097-0.116MWh

(770kg x 140Wh/kg x 0.000001 MW/W or 770kg x 168Wh/kg x 0.000001 MW/W)

 

Energy: 62-74MWh [Oryu/Toryu, 640SLHs], 70-83MWh [Taigeis, 720SLHs]

(0.097MWh x 640 or 0.116MWh x 720 for Oryu/Toryu)

 

If daily energy consumption at surveillance speed [<4knots] is 6MWh [4] and depth of discharge is 90% for SLH, then maximum endurance is 9-11days [for Oryu/Toryu] and 10-12days [ for the Taigeis].

(62MWh / 6MWh x 0.9 or 74MMWh//6MWh x 0.9)

 

[4] Considering the significant electrical needs of submarine sonar systems and other non-propulsion electrical “hotel load”, then requirement may be 200kW. Energy requirements for propulsion at surveillance speed may be 50kW. Then daily energy consumption is 6MWh (=(200kW+50kW) x 24hours). 

The approximately 50kW [minimum] estimate for propulsion motor is based on the  Japanese National Defense Standard (NDS) (at https://www.mod.go.jp/atla/nds/F/F8004_2.pdf , in Japanese) F8004-2 (General rules for submarine electric propulsion equipment - Part 2 submarine equipped with AC propulsion motor = Soryu MK. I). 

-  Low speed 1 is rotation speed of propulsion motor (19 - 45rpm) [ F8004_2.pdf (44/52) 4.4.1 table].

-  19 rpm is the minimum rotation speed of propulsion motor which is 10% of maximum rotation speed at maximum speed in water (= 20knot/h) [ibid (9/52) 4.4.2. table1, item 4 or 7].

-  Output of propulsion motor is 56.8kW at rotation speed of propulsion motor (39rpm) [ibid (38/52) 4.4.2. table].

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For more launch dates and other details of all these Japanese submarines see Submarine Matters Oyashio-Soryu-Taigei Table here.