Australian Army Shrinking Due to AUKUS Subs Cost

"‘This will make us weaker’: Army restructure faces backlash" see following Sept 28, 2023 article https://www.smh.com.au/politics/federal/this-will-make-us-weaker-army-restructure-faces-backlash-20230928-p5e8br.html

Pete Comment

My estimate of a A$Half Trillion (over 30 years) required for Australia’s future AUKUS submarine purchases is at the expense of less money for Australia’s Army (causing it to shrink).

However, Trump (on the advice of the US Navy) may well cancel the Virginias for Australia. Trump is increasinly likely win the 2024 elections (the betting odds today are Trump 2.60 to Biden's 3.00). Biden's chances are in free fall. Instead Australia may need to wait for a joint build of Australian SSN-AUKUS subs in the 2040s-2050s.

Whatever the AUKUS partners are claiming now, the cost of Australian SSN-AUKUS's only make sense if they are seen as Australian SSGNs equipped with nuclear weapons.  Australia, after all, only has a very small defence budget compared to the other nuclear submarine owning countries (see SIPRI Table 1.). Those countries (see this very useful wiki site) are all great powers (UK, France, India, Russia) or super powers (US, China).

Significantly the great and super power have nuclear powered submarines as their highest priority and most numerous strategic nuclear weapon platforms. Australia may well follow the same nuclear weapon policy.

Pete Renames Taiwan's Submarine Classes TSS-1s, 2s & 3s

I've noticed the potential for great confusion caused by Taiwan's submarine class naming conventions, with successive classes being called Hai Shihs, Hai Lungs and now Hai Kuns (formerly Indigenous Defense Submarines (IDS)) 

As Biden (in his one of his last compos mentis acts) and then the Pope and now the Sec-Gen of the UN have deputized yours truly world Namer-in-Chief of submarine classes (I claim I first, in 2016 used the term "Dolphin 3s" for Israel's Dakar-class) I hereby name Taiwan's Submarines (TSS). So, following this logic: 

Hai Shihs are now TSS-1s

Hai Lungs are now TSS-2s and

Hai Kuns are now TSS-3s.

What's good for South Korea's KSS-Is, KSS-IIs & KSS-IIIs, is even better for Taiwan.

I hope and trust President Tsai Ing-wen will send me but a pittance, just 1% of the TSS-3s' program budget, for this kindly act of renaming? :)

Cheers Pete

South Korean Boomer (Bomber in UK RN slang) Ambitions

By Shawn Chung

This article started off as a long email chain between Peter and me, that was a spin off of Peter’s article on a potential South Korean submarine-based nuclear deterrent.

As Pete’s article highlights, the increasing nuclear sabre-rattling by Kim Jong Un and North Korea has not been ignored by South Korea, and while South Korea has secured a nuclear defense deal with the US, developing an indigenous South Korean nuclear deterrent is no longer a taboo subject. 

But what are potential SK nuclear delivery systems? 

South Korea actually has a series of ballistic and cruise missiles under the Hyunmoo program, which is detailed in this excellent article from Navalnews.com. Hyunmoo systems were recently seen at the South Korean Armed Forces Day parade, which included drones, cruise missiles, the L-SAM BMD missile system and the Hyunmoo V, a new 3,000km MRBM. South Korea is also researching Hypersonic Cruise Missiles. 

https://youtu.be/CkLf2rAeKnQ?si=_bdQcN_bYQdyNRBg

Now, while South Korea could potentially equip the Hyunmoo V with a nuclear warhead, it is a land based system and in the information age of spysats and synthetic aperture radar, vulnerable to a pre-emptive strike. Submarine launched nuclear weapons, however, have the advantage of ‘hiding out of sight’ for second-strike and strategic nuclear deterrence, and South Korea already has ballistic missile submarines, so to speak.

Both HHI and Hanwha Ocean are currently building the Dosan Ahn Chanho-class (KSS-III) submarines for the ROKN for nine submarines in three batches.

Three KSS-III Batch-I boats have been completed (one was built by HHI, two by Hanwha/DSME). Batch-I boats are equipped with 6 K-VLS for SLBMs and cruise missiles, and can carry the 500km Hyunmoo 4-4, which has a conventional payload. Batch-I submarines are crewed by 50 submariners, and are reported to displace 3,400 tons (surfaced), are 83.5m in length and use AIP fuel cells, with a maximum range of 19,000KM.

Hanwha started construction of the first KSS-III Batch-II boat, with the keel laid in March 2023. While the three batch-III boats are larger, and while crew size is unchanged, displacement is now 3,600 ton (surface) displacement, 89m in length, they will have updated sensor and combat systems, including lithium ion batteries and 10 VLS.

While the current K-VLS launcher, with a 9.8m length, just fits within the hull of the KSS-III submarines, and they carry the Hyunmoo 4-4, which has a 500km range, so it’s just able to reach Pyongyang if it’s fired off the East coast of SK, near Pohang. This means that the KSS-III have relatively short ballistic missile range, and need to stay within an area around the Korean Peninsula to strike North Korean targets. The KSS-III likely can use Hyunmoo-3C cruise missiles with a 1,500km range, but as the Ukraine-Russian conflict has shown, cruise missiles can be countered by a significantly alert and equipped air defense system.

While first two batches of KSS-III can be considered ‘tactical ballistic missile submarines’, the following three Batch-III boats, the first of which is expected to be delivered as early as 2027, could be a real boomer - an SSB armed with 3,000km (Nuclear) SLBMs.

Batch III boats have always been expected to be the largest of the three batches, and they could incorporate, from the construction yard, large VLSs that can launch 3,000km SLBMs derived from the Hyunmoo V. An South Korean SSB could hide in the Philippine Sea, where its AIP/Lithium Ion would enable the sub to lurk for extended periods of time submerged.

The South Korean Agency for Defense Development, has just issued an RFP for the development of a large VLS that could launch a ‘proper size’ SLBM, with a prototype to be tested underwater by 2026.  Navalnews has also implied that South Korea may adopt a missile module, similar to the Virginia Payload Module to add more firepower to the earlier KSS-III batches.

Too Few Taiwanese Subs, TSS-3s Probably Too Late.

This article pre-announces the launch of Taiwan's first domestically built submarine, now known as the Hai Kun-class [TSS-3s] or ("Narwhal" a whale with a sharp tusk, in English) was launched at CSBC Corporation's Kaohsiung shipyard on Sept 28, 2023. First of class, Hai Kun, will undergo harbor acceptance trails from Oct 1, 2023. It might be delivered to the Taiwanese Navy before the end of 2024. A second IDS is expected to be delivered by 2027.

Meanwhile Taiwan’s 2 Dutch built Hai Lung-class [TSS-2] subs, launched in the1986, are 37 years old. Too old, with much obsolete equipment and probably noisy, to be considered fully operational. Taiwan’s 2 World War Two US built Hai Shih-class [TSS-1] sub’s are 79-80 years old, making them accidents waiting to happen, hence very scrap worthy. 

The PRC’s government instructed Global Times reported, Sept 25, along the lines – Taiwan is dreaming if it thinks its 2 modern [TSS-3] submarine force, by 2027, will make much difference. In addition to many more PRC subs the PRC has many other ASW platforms, including aircraft and surface ships. 

Pete Comment

Taiwan’s two TSS-3s by 2027 are probably Japanese designed (with a resemblance to Japan's Soryu or Taigei classes and Taiwan's TSS-2s) and joint Taiwan-Japanese built. As I commented on Sept 29, 2023, all subs are a blend of derived shapes and contents, so the TSS-3s combine ancestor designs, including:

-  Japan 1967 Uzushio-class design which adopted the US 1956 Barbel-class teardrop shape, for more rapid and efficient/longer range fully submerged travel. After the Uzushios Japan gradually made their submarine classes more a bit cigar shaped.

-  Also the Barbel teardrop design came via the Dutch built TSS-2 design. 

As both Japan and Taiwan have efficient shipbuilding industries the 2 TSS-3s will have been built very quickly. But if the PRC invades by the oft described target year of 2027 Taiwan's two modern TSS-3s subs and (by then) two 40 year old TSS-2s will be quickly destroyed. A larger force of US SSNs (Trump permitting) and Japanese SSKs will be very much needed to aid Taiwan. 

I assume the PRC has added to its numerous mobile ASW resources with an intense network of fixed undersea sensors and smart mines programmed to detect and destroy Western (including Taiwanese) subs and ships.

In support of my TSS-3s are Japanese designed theory: Compare model (photo above from many outlets) of a TSS-3 with the similar rather long fin/sail in a similar position also with X-cross rudders of Japan's Soryu and Taigei classes. JS Taigei is below (Photo courtesy Seaforces online).

Ukrainian Missile Hits Russia's Crimea Fleet HQ

On 22 Sept, new Ukrainian missile strike makes Russia's cost of aggression, that much more expensive.

https://www.businessinsider.com/russias-black-sea-fleet-headquarters-hit-another-blow-forces-crimea-2023-9

Russia’s Black Sea Fleet (Crimea) HQ building with new large "entrance" 22 Sept.

(Photo courtesy Jimmy Rushton on “X”)

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A Nuclear Armed South Korea? Confidential Reactions

I’ve been casting a net to confidential contacts on the issue of South Korea (SK) converting its conventionally missile armed KSS-IIIs to subs providing a nuclear deterrent. The following are their responses, speaking under protection of anonymity:

South Korea: We SK politicians and public are increasingly positive about building our own nuclear deterrent. This is because any nuclear free Korean peninsula policy is now an out of date fantasy. A Trump or even an isolationist Democrat win in the 2024 US Elections is too much of a (remove the US nuclear umbrella) risk to our homeland.  

We more than realize that our KSS-IIIs are the only SSBs (which stands for conventionally propelled submarines (SS) armed with Ballistic missiles) in history that are not nuclear armed. Also all SLBMs (except ours, so far) have been nuclear armed. Historically Soviet SSBs were nuclear armed and it is strongly suspected Israel's INS Drakon and then Dakar-class will have SLBMs that are nuclear armed.

We may have a joint program with Israel for developing an SLBM. 

UK and France: We great-middle powers see submarines as the most reliable nuclear weapons delivery platforms. This is because the other 2 launch modes: air bases (for nuclear armed aircraft) and land based missile silos (on countries like ours with small land areas) can be “taken out” within a few minutes by enemy first strikes.

South Korea: Our country, SK, suffers from having a small land area and sharing a border with our main threat, North Korean (NK). This means NK could launch a disarming nuclear first strike (taking out our air bases and any missile silos) in less than 10 minutes. So viable second strike deterrents must be SSBs that are difficult for NK and any other country to find. 

Developing boosted fission weapons is a much higher priority than developing nuclear propulsion for subs. 

China: We are concerned that once SK publicizes its nuclear deterrent (or the SK "Bomb" is revealed by espionage) this will have unwelcome impacts on NK and Japan. 

We may not be able to restrain NK from taking violent and unpredictable nuclear and/or conventional military actions against SK. A Korean nuclear war on our doorstep could mean radiation blowing into highly populated northeast China and a large Korean refugee problem streaming over the border. 

Japan: We are a rival to SK. A nuclear armed SK would remove the "nuclear taboo" limiting our nuclear weapons proliferation. We will likely and eventually react, on hearing about a nuclear SK, by publicizing our own nuclear weapons, capabilities or plans. We realize that China may be somewhat concerned about a militarily resurgent nuclear armed Japan, but we will always be weaker than China.

Russia: Rolling nuclear weapons proliferation that includes SK and Japan will raise tensions in China and NK to our south. We border China and North Korea. Chinese nuclear weapons growth might accelerate. While we are currently friends with China we are also regional and world political rivals. We don't want that rivalry to become a nuclear and conventional arms race with China. We also don't want nuclear or even conventional war in the Korean Peninsula. 

We don't want to be drawn into northeast Asian conflicts while we are fighting in what we insist are dissident, NATO proxy, Russian territories like Ukraine, Finland and other naturally Russian Baltic states. Also northeast Asian conflicts would be bad for our oil and gas exporting businesses.  

Australia: If SK and Japan publicize their nuclear weapons capability we will eventually publicize ours. Our future SSNs, when armed with better missiles than Tomahawks, will be our logical nuclear weapons platforms.

US: Who knows?! Our views depend on whether we get Trump back. Biden's lead over Trump has "evaporated". God help us! I'm also not sure our aging Biden, a steady hand on SK, will contest the November 2024 presidential election.

wispywood2344 on Japan's New Defense Projects

Pete Comments

In its Central Asian region Russia maintains powerful forces of nuclear armed long range bombers and ICBMs. Russia's Pacific Fleet also contains many SSKs, SSNs and SSBNs all a potential threat to Japan. China is rapidly increasing its conventional and nuclear naval forces to rival Russia's with China also presenting many potential threats to Japan. North Korea is also a threat with steadily improving and potentially nuclear armed long range missiles - sometimes being test flown over Japan's home islands and territorial waters. 

In the face of this Japan is increasing its defense budget to amounts and percentages of GDP not seen since World War Two. See Naval News' August 31, 2023 article "Japan Requests Largest Defense Budget Ever".

Japan’s Fiscal Year FY2024 Defense budgetary request of 7.7 Trillion Yen (US$52.9 Billion), an increase over FY2023’s budget of US$46.8 billion.

But when one compares US$52.9 Billion with Japan's US$4,410 Billion 2023 nominal GDP Japan's defense budget is still only 1.2 percent of Japan's GDP. Yet Japan's defense budget is growing rapidly. Japan's defense industry is also highly efficient.

Aegis system equipped vessel (ASEV). (Courtesy Japan MoD image via NavalNews).

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Amongst items requested are two 12,000 tonne cruiser sized Aegis system equipped vessels (ASEVs) (above) and two 8,200 tonne Maya-class Aegis destroyers.

Modifications of Japan’s JS Izumo and JS Kaga defacto aircraft carriers (US$290 million) to better accommodate F-35Bs. Modification of Kawasaki P-1 maritime patrol aircraft (MPA) to emphasize electronic warfare (US$95.7 million).

wispywood2344

To meet these threats Japan is gradually improving its high tech defenses. To that end long term contributor wispywood2344 on September 9, 2023, reports on three weapon systems:

Among the 17 R&D projects included in Japan’s Fiscal Year FY2024 Defense budgetary request, I would like to introduce matters related to "Submarine Matters".[1] 

[Artwork of Combat Support Multipurpose USV concept courtesy NavalNews]
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A)  Combat Support Multipurpose Unmanned Surface Vehicle (USV) [2].

The outline is as follows:

1. Selective equipment; sensor (possibly sonar and ESM antenna), anti-ship-missiles, anti-submarine-torpedoes, etc. .

2. Submersible for stealth.

3. Remotely controlled via SATCOM.

4. Automatic navigation in bad sea state.

5. Able to act as a fleet" in cooperation with multiple USVs.

6. This project will cost 24.5B yen (US$167,587,355 in total and complete by FY2030.

[NavalNews reports: To quickly acquire knowledge of USV operation and promote the development of domestically produced USVs, the Japanese defense budget calls for the procurement of USVs that have been used in various countries as test equipment.]

[A current version Type 12 LWT being launched (Photo courtesy Weaponsystems(dot)net)]

B)  Improvement of Type12 Lightweight Torpedo (LWT) (photo above) [3].

The outline is as follows;

1. Add anti-torpedo (hard-kill) capability to Type 12 Lightweight Torpedo (LWT).

2. Improve the surface ship sonar, to enable effective operation of improved Type 12 LWT.

3. This project will cost 12.5B yen (US$85,525,746) in total and complete by FY2029. 

Artwork courtesy Raytheon of a GPI concept (via NavalNews).
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C)  Japan-U.S. joint development of "Glide-Phase-Interceptor" (GPI) [4].

The Japanese MoD starts development of land-based Glide Phase Interceptor system (artwork above) used against Hypersonic glide vehicles (HGVs) this year. [5][6][7]

[Project may cost equivalent to US$512.7 million]. From next year onward, it will participate in the US's ongoing development project of sea-based GPI system. Also see here and here.] 

In my opinion, Japan will be responsible for the upper stage rocket motor, similar to the Japan-US jointly developed SM-3 Block IIA. [see references to Japan here.] 

[1] https://www.mod.go.jp/j/policy/hyouka/seisaku/2023/jizen.html

[2] https://www.mod.go.jp/j/policy/hyouka/seisaku/2023/pdf/jizen_01_honbun.pdf

[3] https://www.mod.go.jp/j/policy/hyouka/seisaku/2023/pdf/jizen_16_honbun.pdf

[4] https://www.mod.go.jp/j/policy/hyouka/seisaku/2023/pdf/jizen_17_honbun.pdf

[5] https://www.mod.go.jp/j/approach/hyouka/seisaku/2022/pdf/jizen_12_logic.pdf

[6] https://www.mod.go.jp/j/approach/hyouka/seisaku/2022/pdf/jizen_01_logic.pdf

[7] [See cool animated video of a GPI in action] https://www.youtube.com/watch?v=PzUFHvvUNGU#t=3h09m31s

NK's New "SSB" Missile Firing via Test Barge?

H I Sutton's September 8, 2023 article, on the September 6 launch of North Korea's (NK's) possible 10 missile SSB, is most interesting. 

My inititial thoughts are the SSB (especially in main picture below) looks too top heavy (submerged or surfaced) to be a stable missile firing platform. It may be a propaganda response to South Korea's 10 missile KSS-III Batch 2 SSB.

North Korea's new SSB. Artwork/photos courtesy H I Sutton for NavalNews.

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So it is unclear if this NK SSB has the stability to fire its missiles (then its VLS tubes are presumably backfilled with water?) and then be able to surface without dangerously leaning on its side.

To avoid such a happening the following information, of September 8, 2023, from 38 North may be very significant: 

"Just 24 hours later, on September 7, in a puzzling occurrence, the submersible ballistic missile test barge had been moved from the south protected basin and was nested outboard of the newly launched submarine."

This may suggest that NK may soon film firings of new larger (Pukguksong 4 or 5?) missiles purportedly launched by the SSB. But actually fired from the submersible ballistic missile test barge. 

This propaganda hoax will then be believed by much of the Western mainstream media.

Might SSN-AUKUSs Arrive Before Australia's Virginias?

Captain Reifstek, USN (Courtesy LinkedIn)
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From https://www.defensenews.com/naval/2023/09/07/allies-target-early-aukus-milestones-to-keep-20-year-plan-on-track/

It is so nice to see Capt. Lincoln Reifsteck [USN above] Manager, AUKUS Integration and Acquisition Program, said:

1.  “Australia has very sophisticated manufacturing capabilities for certain kinds of parts and could take on work for the collective AUKUS nuclear sub supply system.”

Pete Comment: That the US and UK would outsource parts of their submarine supply chain national security to efficient Australia is a welcome surprise.

2.  “the U.K. will begin building its first [SSN-AUKUS] later this decade [ie. in the 2020s]”

and

3.  “Australia will follow “very shortly thereafter””

Pete Comment: So the UK’s very limited (usually late) submarine design/build workforce leapfrogging the 15 year Dreadnought SSBN program (lead Dreadnought to be commissioned in the early 2030s) in order to start building SSN-AUKUS in the 2020s is also a surprise. My spies advise both submarine types would need to be built in the same Barrow-in-Furness shed.

It is all happening so fast, it seems. What could go amiss?

Virginia Purchase: US Dollars vs Australian Dollars?

Some interesting financial figures have come out of AFR’s “AUKUS export rules possible ‘Trojan horse’ for bad actors” of 7 Sep 2023 by a US author
at https://www.afr.com/world/north-america/aukus-export-rules-possible-trojan-horse-for-bad-actors-20230907-p5e2mt  eg:

1. ““Obviously, we were grateful that the Australians want to invest [donate] $US3 billion…” 

Pete Comment

Apparently the Australian donation is 3 billion US dollars, not Australian dollars as I previously assumed. US$3 billion = A$4.7 billion.

The Australian Government's decision to not publish details of Australia's donation to the highly profitable US arms industry should concern Australian taxpayers. Details of the dollar currency and over what period should be published. 

This is also noting that Australia's donation will not make much of a difference to US submarine building - an industry that needs 10s of US$Billions to pay 10,000s of extra workers to double or triple production of Virginias (currently only 1.1 Virginias on average are being produced per year).  

See the enormity of the US Navy Virginia shortfall on pages 50 and 17 indicated here. Many in the US Navy, Congress and the US Government see 3 to 5 Virginias to Australia as making the shortfall worse. 

After the US was burnt in relaxing sensitive technology export controls to Canada, many Americans also have security concerns about Australians having access to tightly held US submarine, including reactor, secrets. This information flow reluctance could come to haunt us as Australia, without extensive nuclear reactor industrial base experience, is hoping to operate highly complex Virginia reactors.  

and

2. “The Congressional Budget Office estimates that each new [Virginia] submarine could cost between $US6.2 billion ($8.7 billion) and $US7.2 billion, materially higher than the US Navy’s $US5.6 billion estimate.” 

Pete Comment

$US7.2 billion = A$11.3 billion that Australia may need to pay per Virginia at today’s prices? 

One wonders what 10 years of (say) 3% US cumulative inflation would do to US costs in terms of upfront purchase prices, spares, major upgrades, derusting and repairs for the first refurbished but scarce Virginia in 2033?

Too Few Astutes, Osborne Spruikers, Too Few Virginias

The AUKUS sub Dog's Breakfast (as in dog vomit) Labor's Albanese inherited.

(Cartoon courtesy Eureka Street)

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The UK has a poor SSN production and availability record that bodes ill for the UK designing and part building SSN-AUKUS’s for Australia in the 2040s. The UK’s 6 SSNs (5 Astutes and 1 Trafalgar) are reportedly stuck in Devonport and Faslane  docks - a dangerous situation of neglect and miscalculation.

It will be difficult for the UK Royal Navy (RN) to spare an Astute for "Submarine Rotational Force-West" at HMAS Stirling, from 2027, if there are insufficient operational Astutes even for the RN. This is noting at least 1 Astute is required near  Faslane for "delousing" (ie. protecting) UK SSBNs leaving Faslane on patrol and then returning to Faslane. Another Astute is expected to be on station in the eastern Mediterranean or patrolling the North Atlantic/GIUK Gap (against increasingly active Russian subs). If the RN wishes to maintain 3 operational Astutes (for its Australian, Faslane and another Atlantic-Mediterranean  commitment) the RN needs 9 Astutes to meet the Rule of Thirds - but the RN is only building 7 Astutes. 

The combination of an inefficient UK SSN build sector and Australia having probably the most inefficient shipbuilding sector worldwide will be too costly for even the loudest Osborne spruiker to flog.

This is on top of likely US unwillingness to provide Virginias to Australia in the 2030s due to the USN having too few SSNs even for its own use. 

Australian Made Cardboard Drones Bomb Russia

https://www.abc.net.au/news/2023-09-03/ukraine-war-australian-made-cardboard-drones-russia-warfare/102804120

Submarine Communications

Submarine Matters strives to bring all manner of submarine topics to you the reader. To that end Anonymous reported on August 22 and Unknown reported August 23, 2023, on submarine reception of signals. Pete has done some English from another language editing and has also attempted more explanations of these highly technical topics, with lots of question marks ? when issues need clarification.

For the last 7 to 10 years NATO standard Link 11 due to a low data rate? deficiency has been upgraded to Link 16 [maybe a tactical version of Link 22 ?]. With Link 22 being a packet, internet protocol (IP) system in the HF and UHF radiofrequency bands. Link 22 operates in the 1 GHZ range to have broader bandwidth for higher bit rates to transmit maps and video, etc.

Link 22 allows for very small antennas (A quarterwave is about 7 cm) but at these frequencies you have to be in the line of sight and to achieve high gain using a small parabolic dish (30/40 cm?) on the surface (searching and tracking automatically the right satellite) is needed.

Powerpoint slide courtesy Thales.
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France's Barracuda SSNs use Links 11, 16 and 22 via the Thales DiveSat (see above) antennas. The German Aeromaritme company has specific radio masts probably functionally identical.

This is "passe" (designed 15/20 years ago) however with the emergence of Phased Array matrix detectors at very low cost (Starlink internet terminal includes a flat antenna that can scan and track satellites automatically (valued) at US$500.

"A submarine towing a flat plastic black sheet 30 cm in size on the surface..(with  electronics and a power source, FO? link for the data) Detection?..Retrofit likely." [Pete knows not what is meant by this!]
 

(Artwork courtesy France's NEREIDES) A UK RN SSBN? in the Indian Ocean towing a buoyant wire antenna to receive messages from a large land based VLF transmitter array of the type at Naval Communications Station Harold E. Holt at Exmouth Western Australia?
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As for buoyant wire antennas (towed by subs - see above) they are useful in the HF  band, at 10/30 Mhz, for traditional radio links over long distances, up to 10,000 miles if the seasons and the ionosphere are ok

There is no need for an (indiscrete) surface wire with VLF [see NEREIDES' artwork above] because in the 3/40 KHz the Electromagnetic (EM) field penetrates down to 20 meters. Although a long surface wire is far better for reception. However the bandwidth at these frequencies is in a fraction of kbits/sec order of magnitude, less than the old traditional analog phone using a landline of Thomas Edison in 1890.

Pete Comment

It is always assumed that submarines merely receive messages and "never transmit" to Headquarters for instructions. This is demonstrably false.

It need be remembered that concerning the first and only time a nuclear submarine has torpedoed a ship in battle - HMS Conqueror sinking General Belgrano in 1982 - HistoryNet records:

“…Conqueror duly reported its change of direction to London at 1400 Zulu [time]. Then, despite problems with its communications equipment, at 1710 Zulu the British submarine received and acknowledged the new [Rules of Engagement] ROE and orders to attack. At the same time Cmdr. Chris Wreford-Brown, Conqueror’s captain, transmitted his intention to strike the enemy..." 

Presumably HMS Conqueror used an HF, UHF or VLF? radio transmission encrypted and aimed at a satellite for security? to report to London and to acknowledge London's orders.

See Comments from Anonymous at 9/01/2023 9:53 PM and Shawn C. at 9/01/2023 10:25 PM clarifying some of the issues above.