DRASS DG-160: Black Sea Submarine Mystery: Part 1

In late 2023, H I Sutton kicked off a flurry of media speculation when he published an article on his Covert Shores blog about the DRASS DG-160 midget submarine. This submarine, or two, are separately or jointly under construction at the DRASS fabrication facilities in the Romanian towns of Timisoara and Giurgiu . The Giurgiu assembly site is significant in that even though it is 600km away from the Black Sea a DG-160 could be barged on inland waterways to the Black Sea.

Map of the Black Sea. Note how shallow the seafloor is off the Romanian and Bulgarian coasts. Minisubs like the DG-160 are better suited to the shallows than medium sized SSKs. (Map courtesy Brittanica).
---  

This DG-160 is for an "Undisclosed Customer" claimed Sutton. It is for "Ukraine!" claimed a host of many pro-Russian media outlets. As will be explained below DRASS's assembling DG-160s at Giurgiu factory has politico-legal advantages if the intended customer is the Ukrainian Navy.  

Artwork: DRASS
---

I did some googling (without resorting to Gemini AI) and discovered a YouTube link, available on the DRASS website, to the actual TVR News Romania report that H I Sutton referred to for his article. 

DRASS DG-160 Youtube here and above uploaded by DRASS in 2022.
See all DRASS underwater videos.
---

As you can see, the above is basically an infomercial about DRASS producing the DG-160 midget submarine. So DG-160s are actually built at two Romanian factories - at Giurgiu and 500km away at Timisoara. The Timisoara Romanian factory also produces hyperbaric chambers, diving bells and swimmer delivery vehicles. 

In a 2019 article published by European Defense Review Magazine, a prototype of the DG-160 was designed at DRASS's Livorno, Italy HQ. Actual production commenced into 2021 at Timisoara, Romania after a 2 year COVID delay.

The technical achievement of producing DG-160 subs in Romania was leveraged patriotically by the Romanian Defense Minister in the face of Romanian concern about Russia's February 2022 Ukraine invasion. The Minister envisaged exporting DG-160s as well as supplying them to the Romanian Navy.

Would 6 x DG-160s meet Romania's needs for the Black Sea? possibly. DRASS claims 6 could be bought for the price of a single modern SSK (presumably implying a Scorpene - see below) and they can provide a long-range delivery means for combat divers.

Under the 1936 Montreux Convention, Turkey has the right to block warships (including submarines) attempting to enter the Black Sea via Turkey's Bosporus and Dardanelles straits. At Ukraine's request Turkey exercised this right by blocking all warships on February 27, 2022. This resulted in the blocking of Russian Kilo submarines in mid 2022 and later two large Russian warships. Even two small Ukrainian warships (minehunters) were blocked in January 2024.

Under the Montreux Convention Turkey could even decide to block future imports of submarines to Bulgaria and Romania as both countries border the Black Sea. The Bulgarians have been looking for second-hand subs (likely Turkish Type 209s). Romania in July 2022 signed a letter of intent with Naval Group for 2 new Scorpenes. The possibility of a Turkish blockage could particularly be felt if the Ukraine-Russia War drags on through to the time that French built Scorpenes for Romania are ready. Even France shipping sections for assembly in Romania could be blocked.

Turkey attempting to use its Montreux Convention power to make itself a monopoly supplier of submarines to Romania, might make Turkey unpopular in international legal circles. Perhaps less so to Bulgaria if other submarine exporting countries accepted Bulgaria already wanted to buy Turkish submarines.

The Turkish Navy operates Type 209 class SSKs, as well as Reis-class (Type 214TNs) all located at Turkey's Black Sea Bartin Naval Base which features Submarine Shelters. As the Type 209s are already in the Black Sea Turkey could claim it is not breaking the Montreux Convention by supplying them to other Black Sea countries.

Romania supplying 'home' built DRASS DG-160s for its own navy and for possible export to other Black Sea countries (Bulgaria, Moldova and Ukraine) could be seen as a hedge. That is a hedge against Turkey conferring upon itself monopoly supplier of submarine status under the Montreux Convention.

How Submarine Deployment Impacts Sleep Quality

Might sleep impacts in diesel-electric submarines be different from those impacting nuclear submariners? Might a sleep deprived SSBN Trident D5 nuclear weapons officer (above) pull the big red buttoned trigger in error? Will nuclear defenders everywhere exude the inner glow of the long gone (free fall nuclear bomb) B52 spelling the end of personkind? These, and other questions are untouchable in the following overt tip of a largely classified iceberg, as we don't know it. 

Will Harris, a third-year medical student at Harvard Medical School, has penned an article of May 14, 2024 for Sleep Review magazine. Before medical school, Will Harris served as a nuclear submarine officer in the United States Navy for eight years. The article is at https://sleepreviewmag.com/sleep-health/demographics/career/submarine-deployment-sleep-quality/ :

"How Submarine Deployment Impacts Sleep Quality
of May 14, 2024

A submarine officer-turned-medical-student strives to understand how submarine deployment can affect cognition and sleep quality.

By Will Harris

As a medical student interested in providing better advice on sleep habits to my patients, I recently started reading the book Why We Sleep by Matthew Walker. In its first chapter, the book describes the Mammoth Cave sleep experiment, in which two researchers lived underground for 32 days with a constant ambient temperature and no exposure to natural light. 

Living in a cave for more than a month might seem like a radical idea, but to me, it feels familiar. Thirty-two days in a confined space with constant ambient temperature and no exposure to natural light seems like a fairly short period, actually. I’ve lived in such an environment for well over 100 consecutive days. And thousands of people are living like this right now onboard nuclear-powered submarines.

Life on a Submarine

Before starting physician training at Harvard Medical School, I was a submarine officer in the United States Navy. I spent three years on board a nuclear-powered fast-attack submarine based in Bangor, Washington. During this time, I spent about one year underwater. 

Life on board a submarine can be challenging for many reasons.

• You might see the sun through the periscope occasionally if you’re lucky. There is no other exposure to natural light. 
• Submarine crews do not always follow a 24-hour day. An 18-hour day is common, in which sailors are typically awake and working for about 12 hours and asleep for about six hours.
• The diet consists of canned fruits and vegetables (fresh produce runs out after about a week), powdered milk, frozen meat and fish, and baked goods. 
• In terms of exercise, a crew of about 150 sailors can share one exercise bike, some free weights, and one or two treadmills (depending on the submarine’s size).

Since all American submarines are equipped with nuclear reactors, they have the fuel to stay at sea for decades. They also can create oxygen and water. So time at sea is limited only by the amount of food carried on board.

Since leaving the submarine force and starting medical school in 2021, I’ve thought a lot about the physiological impacts of a submarine deployment. Here is what I’ve learned about how an 18-hour day on a submarine deployment can affect cognition and sleep quality. 

Three Studies on Submarines and Sleep

Researchers have tested the effects of circadian rhythm and sleep-wake patterns on cognition and sleep quality using a protocol called forced desynchronization, under which participants follow a consistent sleep-wake cycle that is different from 24 hours.

A 1999 study used submariners following an 18-hour-day schedule as test subjects for studying circadian rhythm. The submariners followed a typical work-sleep schedule of 12 hours working and six hours sleeping during a three-month patrol. Saliva samples were taken periodically to measure melatonin levels. This study found that the circadian period of test subjects remained around 24 hours.

We can feel confident that submariners’ circadian rhythm continues to follow roughly a 24-hour schedule, even if they do not. But how does the 18-hour day affect cognition and sleep quality? 

Here, it’s helpful to look at a study in which researchers examined neurobehavioral function and cognition in humans living in a 20-hour day. Test subjects were scheduled for 15 to 24 cycles of a 20-hour rest/activity cycle. Data was collected on circadian parameters such as melatonin and core body temperature, cognitive tests including short-term memory and reaction time, and sleep was assessed using an electroencephalogram. They found that sleep performance and cognition suffered when the circadian rhythm was out of phase with the sleep-wake cycle.

One final study to consider: In 2015, researchers looked at sleep quality for submariners on a 24-hour schedule. Crewmembers underwent polysomnography (PSG) at the beginning of a submarine deployment and on day 51. They also completed surveys on subjective sleep quality. This study found that sleep quality did not suffer based on PSG evaluation or survey data.

Desynchronization Impacts Sleep Quality

In summary, life onboard a submarine presents many challenges, including an 18-hour sleep-wake cycle, lack of natural light, lack of fresh fruits and vegetables, access to exercise equipment, and potential exposures.

Several studies show that sleep-wake cycles and circadian rhythms become desynchronized during an 18-hour day, and such desynchronization can negatively impact sleep quality and cognition. There is evidence that submariners on a 24-hour day do not have their sleep negatively impacted, which suggests that poor sleep is due to an 18-hour day rather than other exposures onboard a submarine, such as the lack of natural light."

How a Virginia Block V SSN Works

 

Here and above is an animated explanation of how a Virginia Block V works.
(Video courtesy AiTelly uploaded July 2023)
---

Collins LOTE Part 2: Replacements & Upgrades?

See official "Details" about the LOTE.

Following Collins LOTE Part 1: Budgeted. Saab, LM & MTU of April 22, 2024 what replacements and upgrades are needed for the LOTE?

If the 6 Collins were Life of Type Extended ("LOTEed") from 2026 at 2 year intervals the first 2 would probably retire in the 2030s with the remaining 4 soldiering on through to the mid 2040s. 

Main items I think worth replacing or upgrading are: 

- replacing the Collins’ 3 x Garden Island-Hedemora DIESELS. These are probably no longer in production. They are relatively compact permitting all 3 to sit parallel - saving space. However they are probably unreliable (in the saltier waters of the Indo-Pacific) - so probably need a high level of expensive deep maintenance. The 3 might be replaceable by 2 more powerful Kawasaki 12Ｖ 25/25 SB-type or 2  MTU 4000s submarine diesels (that for more than decade have become highly mature for Indo-Pacific conditions). So, as replacements, 2 x MTU 4000 submarine diesels for each Collins might be reasonable. 

-  maybe new Generators to replace the 3 × Jeumont-Schneider generators with 2

-  strengthening the pressure hulls, as the need for extensive hull cutting to replace/overhaul the Hedemora Diesels has weakened the pressure hulls, reducing safe diving depth.  

-  many combat system items: ie. photonic aka optronic masts replacing existing periscopes, latest technology work stations, new servers, new hardware and software to torpedo tube launch Australia's new Tomahawk anti-ship and land attack missiles. 

-  many worn mechanical moving parts and seals need replacing 

-  electricals that have water damage need replacing, as they can corrode, then fuse, then catch fire. 

-   Lithium-ion Batteries (LIBs) perhaps cannot be retrofitted into the Collins. The Collins' balance/buoyancy, electrical and electronic fittings and components have been built specifically around Lead-acid Batteries (LABs).

Timings

I'm not convinced the Virginias will be delivered to Australia in the 2030s as the US will lack enough Virginias even for the USN. See pages 19 to 20 of this CRS Report. US Virginia production might reach "shareable levels" (phrase coined here first) after the US' new Columbia-class SSBNs "are expected to be completed" in 2042. 

Even LOTEed Collins will only last till the mid 2040s when their pressure hulls become too metal fatigued due to contraction-expansion cycles. 

So Australia may increasing need to rely on AUKUS Pillar 2 generated Ghost Shark XLUUVs from the early 2030s to do everything except fire torpedoes and missiles.

Virginias and/or SSN-AUKUS's might be available to the RAN from the mid-late 2040s. 

Sweden wants Larger Warships and More Submarines

As I highlighted in March 2024, Sweden's March 7, 2024 entry into NATO has accelerated Sweden's overall military procurement. With the publication of a document (298 pages in Swedish) by the Swedish Parliamentary Defense Committee, Sweden is now looking at long-term programs for the 2030s.

According to Naval News, this report includes a new class of frigates for participation in NATO Standing Naval Forces, and a new submarine class to replace the Gotland boats in the late 2030s.

A30 submarine project

image: SAAB. The Blekinge-class will stop at two, with a follow-on class
 planned
---

To recap - Sweden's A26 Blekinge-class SSKs, which were ordered in 2015, will finally be delivered in 2027 and 2028, and replace the two 38-year-old A17 Vastergotland boats, the HSwMS Sondermanland and the mothballed HSwMS Ostergotland.

The Royal Swedish Navy's (RSwN) three A19 Gotland class submarines are now 28-years old, and should decommission in the late 2030s. The Swedish parliament is therefore considering building four A30 submarines after the Blekinges are completed, for delivery after 2038. The fourth sub will expand the Royal Swedish Navy's (RSwN's) active submarine force to 6 boats. 

The A30 could be a smaller (less capable?) submarine than the A26, but could also carry more weapons.

New Frigates?

image: Finnish Navy. Pohjanmma-class
---

As I also highlighted in my March 2024 article, Sweden decided to construct four new corvettes in 2020. These are the Luleå-class corvettes (named after small coastal towns) which are expected to be delivered from 2030. 

These warships will be larger than the 640-tonnes displacement Visbys. They were initially planned as enlarged Visbys. But a clean sheet design was chosen and these ships could emerge as a cousin of Singapore's 1,200-tonne displacement Independence-class Littoral Mission Vessel (LMV).  SAAB contributed to the basic design of the LMV, and also provided composite superstructures. 

The Visbys will now undergo an mid life update (MLU) to remain in service to 2040.

The Swedish Parliamentary Defense Committee now advocates a follow-on procurement of surface combatants, with deliveries starting in the latter half of the 2030s. Naval News has suggested that a variant of the Finnish Pohjanmaa-class multirole large corvettes (117m long ships with a displacement of 4,300 tonnes) is a prime candidate for this new class of warships. As the Pohjanmaa class recently entered production, with the last ship scheduled for completion in mid-2028,  Sweden could to take advantage of the 'hot' construction yard with a follow-on order.

image: Finnish Navy. Pohjanmaa-class production schedule
---

Note that Sweden does not have large naval shipyards, and SAAB had to build the hull of the 4,000 tonne displacement SIGINT ship HSwMS Artemis in Poland.

Update - 2/05/2024

Naval News has posted a YouTube video interview with the Chief of the Royal Swedish Navy on the sidelines of the Sea Air Space 2024 convention and she confirms that Sweden has already integrated into NATO and is prepared to join the NATO standing MCM and Maritime groups.

Naval News interview with the Chief of the Royal Swedish Navy
---