The Undersea Web - Future of Indian submarine surveillance?

Discussion in 'Strategic Forces' started by Gessler, Apr 17, 2016.

  1. Gessler

    Gessler Regular Member

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    Undersea Webs

    A web of strategic projects is now taking firm shape as India enters into closer multilateral military cooperation relationships with Japan, Australia and the United States, as well as regional powers like Indonesia, Malaysia, Singapore and Vietnam. Matters began taking on urgency in late September 2014, after US President Barack Obama and PM Modi have pledged to intensify cooperation in maritime security. Following this, on March 16, 2015 the defence ministers of the 10-member Association of Southeast Asian Nations (ASEAN) at the end of the two-day 9th ASEAN Defence Ministers’ Meeting in Langkawi, Malaysia, collectively stated that they wanted India to play a far bigger role in both the Indian Ocean Region (IOR) and the South China Sea.

    [​IMG]

    In the near future, therefore, under the auspices of the US–India Defence Framework Agreement, foundational pacts like the Logistics Exchange Memorandum of Agreement (LEMOA), Communication Interoperability and Security Memorandum Agreement (CISMOA), and Basic Exchange and Cooperation Agreement for Geo-Spatial Cooperation (BECA), are likely to be inked by the two countries later this year.

    Concurrently, Japan can be expected to extend funding from the Japan International Cooperation Agency for the upgradation of naval air bases and construction of new ELINT/SIGINT stations along the Andaman and Nicobar chain of islands, which is made up of 572 islands (of which only 34 are presently inhabited), stretching around 470 miles north to south.

    But most importantly, preliminary planning has commenced on a Japan-financed project that calls for

    • 1) laying of an undersea optical fibre cable from Chennai to Port Blair; and

    • 2) the construction of an undersea network of seabed-based surveillance sensors stretching from the tip of Sumatra right up to Indira Point. Once completed, this network will be an integral part of the existing US-Japan ‘Fish Hook’ sound surveillance (SOSUS) network that will play a pivotal role in constantly monitoring all submarine patrols mounted by China’s PLA Navy (PLAN) in both the South China Sea and the IOR. This network will in turn be networked with the Indian Navy’s (IN) high-bandwidth National Command Control and Communications Intelligence network (NC3I), which has been set up under the IN’s National Maritime Domain Awareness (NMDA) project at a cost of Rs.1,003 crores. At the heart of the NC3I is the Gurgaon-based, Rs.453 crore Information Management and Analysis Centre (IMAC), whose systems integration software packages were supplied by Raytheon and CISCO.

    [​IMG]

    • Oblique references to all these developments were made in the joint statement that was issued last month after the visiting US Secretary of Defense Ashton Carter held delegation-level talks with his Indian counterpart Manohar Parrikar. The joint statement spoke about: A) new opportunities to deepen cooperation in maritime security and maritime domain awareness; B) commencement of navy-to-navy discussions on submarine safety and anti-submarine warfare; and

    • 3) enhancing on-going navy-to-navy discussions to cover submarine-related issues.

    [​IMG]
    US-Japan Fish Hook SOSUS network

    The US was always interested in Japanese and Indian locations for its SOSUS stations. Initially called Project Caesar, this involved running cables out on continental shelves and connecting them to hydrophones suspended above the sea bottom at optimum signal depths.

    An ‘experimental station’ was established at the north-western tip of Hokkaido in 1957, with the cable extending into the Soya (La Perouse) Strait. It monitored all Soviet submarine traffic going in and out of Vladivostok and Nakhodka in the Sea of Japan.Undersea surveillance systems and associated shore-based data collection stations code-named Barrier and Bronco were installed in Japan in the 1960s. Acoustic data collected at these sites was transmitted by US defence communications satellites to US Navy (USN) processing and analysis centres in the US.In the 1970s, a network between between Japan and the Korean Peninsula was commissioned.

    By 1980, three stations at Wakkanai (designated JAP-4), Tsushima (JAP-108) and the Ryukyu Islands (RYU-80) were operational in Japan, along with earlier stations built in the Tsushima Straits and the Okinawa area. The existence of old cables at Horonai Point in north-west Honshu, which during the Cold War led out to SOSUS arrays in the Sea of Japan, has been widely described by scuba divers. By the mid-1980s the SOSUS hydrophone arrays stretched from southern Japan to The Philippines, covering the approaches to China.After the collapse of the USSR and the decline of the submarine threat to the US in the early 1990s, the USN allowed its SOSUS systems in the north-west Pacific to atrophy, although some arrays were retained in working order so as to support civilian scientific research (such as tracking whales and monitoring undersea volcanic activity). According to a USN directive issued in August 1994, all seabed-based fixed-arrays in the Pacific were placed on ‘hot standby’; personnel would ‘not be routinely assigned to monitor fixed-array data’ unless that data was required for operational purposes, but in practice the probability of being able to reconstitute them to full operational status was ‘extremely low’.

    [​IMG]
    Project Varsha base

    However, in the early 2000s, facing an increasing PLAN submarine force and more aggressive PLAN submarine patrols, the USN decided that it needed a new chain of fixed arrays designed primarily to monitor the movement of PLAN submarines between the East China Sea and South China Sea on the one hand, and between the Pacific Ocean and the Indian Ocean on the other. Thus was born the US-Japan ‘Fish Hook Undersea Defense Line’ in early 2005, stretching from Japan southwards to Southeast Asia, with key nodes at Okinawa, Guam and Taiwan.


    Beginning from near Kagoshima in the southwest part of Kyushu, it runs down the Osumi archipelago to Okinawa, then to Miyako-jima and Yonaguni in the southern part of the Ryukyu Islands, past Taiwan to the Balabac Islands in The Philippines, to Lomkok in the eastern part of the Indonesian archipelago, across the Sunda Strait between Java and Sumatra, and from northern Sumatra to the Andaman and Nicobar Islands. Three major gaps—between Yonaguni and Suao in north-east Taiwan (120km), between Kaohsiung in south-western Taiwan and the Dongsha (Pratas) Islands (450km) where the East China Sea meets the South China Sea, and across the Bashi Channel (220km) between Hengchun at Taiwan’s southernmost tip and Luzon Island in The Philippines—were plugged. In addition, the USN installed a new SOSUS network, stretching from Sasebo down to Okinawa, in 2006, when the US cable-laying ship USNS Zeus operated together with oceanographic survey vessels and nuclear submarines in this area.In July 2013, Beijing claimed that the US and Japan had jointly established ‘very large underwater monitoring systems’ at the northern and southern ends of Taiwan. One of these stretched from Yonaguni to the Senkaku Islands (about 150km), while the other covered the Bashi Channel down to The Philippines.

    Thus, this US-Japan undersea trip-wire around the PLAN presently extends across the Tsushima Strait between Japan and the Korean Peninsula, and from Japan’s southern main island of Kyushu down past Taiwan to The Philippines. The curve of the hook stretches across the Java Sea from Kalimantan to Java, across the Sunda Strait between Java and Sumatra, and from the northern tip of Sumatra along the eastern side of India’s Andaman and Nicobar island chain. Real-time information-sharing between the US and Japan joins the undersea defence line-up, effectively drawing a tight arc around Southeast Asia, from the Andaman Sea to Japan.

    Continued in Part-2 ...
     
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  3. Gessler

    Gessler Regular Member

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    ...Continued

    China’s Undersea Trip-Wire

    The PLAN’s seabed-based surveillance network, developed jointly by Ukraine and China since 1996, has been under installation along China's territorial waters since 2012, with work expected to be completed later this year. The seabed-based component of this network comprises arrays of hydrophones and magnetic anomaly detectors spaced along undersea cables laid at the axis of deep sound-channels roughly normal to the direction that the arrays are to listen. This capability is next paired with maritime reconnaissance/ASW aircraft assets to establish a multi-tier ASW network. The first naval bases to be covered by this network were the PLAN’s submarine bases in four sites:

    • the Bohai shipyard at Huludao on the Bohai Sea where all nuclear-powered submarines are built;

    • the North Sea Fleet’s Xiaopingdao naval refitbase near Dalian where the SSBNs are fitted out for SLBM test-firings from the Bohai Sea across China into Delingha in the Qinghai desert and the desert of Lop Nor in Xinjiang;

    • the North Sea Fleet’s base at Jianggezhuang (Laoshan) approximately 18km east of Qingdao in Shandong Province;

    • and the South Sea Fleet’s bases at Longpo and Yulin at Yalong Bay near Sanyaon the southern tip of Hainan Island.

    [​IMG]
    Elements of PLAN's SOSUS network

    As far back as 2001, a researcher at the PLAN’s Institute 715 had published a survey of ocean surveillance technologies that included a detailed discussion of the US SOSUS programme. Later, one of the most detailed discussions of China’s seabed-based surveillance networks appeared in the journal Shandong Science in 2010. However, Shandong was apparently not the only coastal area pushing forward with R & D on seabed-based sensors. Further down south and located near Shanghai at the mouth of large Hangzhou Bay, an ‘East Sea Ocean Floor Observation Test Station’, also known as the Xiaoqushan Station, was discussed extensively by Chinese researchers in an article appearing in Science Bulletin in 2011. Focussing on the collection of a variety of oceanographic information—tidal and current data, for example—experimentation with sonars is presently ongoing at this station with a wireless data-collection system that was commissioned into service in April 2009. Another analysis by several PLAN researchers in late 2012 discussed this station and military applications for its seabed-based sensors, alongside civilian uses, including environmental protection, navigation, and disaster prevention.

    The analysis compared different configurations for seabed-based sensor networks, including linear, circular, and tree-type designs, and also evaluating their respective cost, security and reliability implications. It also mentioned the Xiaoqushan Station as the basis for a larger ‘East Sea Ocean Floor Sensor Network’ that will be completed by 2016. The analysis also mentioned undersea mobile sensor stations, as well as fixed seabed sensors.


    In early 2013, China Science Daily’s March 26 edition opted to go public with the system by publishing a feature with the banner headline: “Here They Are Quietly Listening to the Ocean: The Whole Story of the Building of Our Country’s First Deep Sea Ocean Floor Sensor Network Base”. According to this article, R & D efforts had commenced in 1996 and an initial prototype of the seabed-based sensor system was tested back in 2005 in the waters surrounding the PLAN’s base at Qingdao in Shandong Province. An additional site was selected for the Longpo naval base, and work formally commenced there in April 2009. Initial set-up was completed in 2010. The undersea-sensor system has since been integrated with a larger surveillance network that also has airborne and space-based components. Two articles appearing in mid-2013 in the technical journal Ship Electronic Engineering, confirmed that this network was now at an active deployment stage. One article discussed the technical challenge of energy supply by proposing a low-power ‘sleep-wake mode’, and mentioned the interesting additional problem that a country’s undersea sensors are subject to being captured by an adversary. Another article discussed the importance of advances in ‘burst communications’ for enhancing the military value of the seabed-based sensor network. A mid-2012 analysis in the naval magazineModern Ships unequivocally confirmed the existence of PLAN’s network of seabed-based sensors.

    The cover-story of a second quasi-official naval journal, Naval & Merchant Ships from mid-2013, similarly showed an acute PLAN sensitivity to its perceived vulnerability to Western and Japanese submarines. The central concern shown there was protecting the PLAN’s SSBNs, while the main threat vector mentioned was the USN.

    [​IMG]
    Type 094 Jin-class SSBN

    Moreover, it put forward a plausible theory of limited war in the nuclear age: “Limited war theory does not permit the enemy country to become a target. But to win the war one must defeat the enemy’s military forces so that the SSBN can become the ideal target.” The article asserted that the range of PLAN’s SLBMs (the JL-2 SLBM on the Type 094 Jin-class SSBN has a range of 7,400km) must be extended “so that one-way passage to the patrol area is shortened to 5-10 days.” At present, all PLAN-operated submarines are evaluated to be highly vulnerable to detection from “US warships employing active sonar as well as US Navy SSNs lurking near Chinese harbours.” To address this dire situation, the seabed-based surveillance system is deemed critical: “Among the various ASW elements, the seabed-based surveillance system is the foundation and heart, offering advanced warning for the sortie of ASW aircraft and light warship escorts.” The article continued: “The hardest part of ASW is early detection.

    If China can only find the targets, PLAN’s ASW forces can then apply pressure against the activities of US submarines, limiting their intelligence and attack capabilities.” While this article discusses other critical ASW elements—even highlighting the role of aircraft carriers, for example—a clear focus and conclusion of this analysis is the priority to deploy seabed-based surveillance systems. It envisioned a sequential process: “In order for China to build a relatively tight ASW network, we must first [outside of all major fleet bases] construct fixed seabed sonar arrays for continuous surveillance and control of sea areas close to ports.” The analysis further advocates that after building a network proximate to its naval bases, the PLAN should deploy seabed-based sonar arrays to the west of Okinawa, to the east of Taiwan, and into the Luzon Strait.” Nor should China’s ambitions for undersea surveillance be restricted to the “near seas,” according to this analysis, as it suggested that more distant areas, such as the Bay of Bengal, may be appropriate sites for future Chinese seabed-based sonar arrays “in order to support ASW operations in those sea areas.”


    Continued in Part-3 ...
     
  4. Gessler

    Gessler Regular Member

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    ..Continued

    Growing Tentacles

    The PLAN presently has an estimated 60 double-hulled submarines, of which 51 are diesel-electric SSKs;

    • two Type 877EKM

    • ten Type 636

    • 13 Type 039 Song-class

    • four S-20/Type 041A Yuan-class,

    • four S-20/Type 041B Yuan-class and

    • 18 Type 035 Ming-class and

    • eight (four Type 091 Han-class and four Type 093 Shang-class) are nuclear-powered SSNs.

    In addition, there’s one Type 092 Xia-class and two Type 094 Jin-class SSBNs, with five more of the latter due for delivery in future. Also due for procurement in future are 15 single-hulled SSKs (most likely Russia’s Amur 1650-class) powered by indigenously-developed Stirling Engine air-independent propulsion systems.

    The number of PLAN submarine sorties has approximately quadrupled over the last seven years, with an average of 12 patrols being conducted each year between 2008 and 2015, following on from six in 2007, two 2006 none in 2005.

    In the Indian Ocean region (IOR), the PLAN has so far carried out three submarine patrols (all accompanied by Type 925/Type 926 submarine tenders), with the submarines being kept its vessels out at sea for 95 days during each patrol.

    [​IMG]
    Type 091 Han-class and 093 Shang-class SSNs

    The PLAN’s first SSN patrol within the IOR lasted from December 3, 2013 till February 12, 2014. One Type 093 Shang-class boat left Longpo its bastion at Yulin on December 3. Ten days later, on December 13, the SSN reached the Gulf of Aden via the Ombai Wetar Strait near Indonesia. It remained on patrol in the area for nearly two months.

    Next to follow was the Type 039 Song-class SSK ‘Great Wall 0329’, which later docked at the China-funded Colombo International Container Terminal in Sri Lanka from September 7 to 14, 2014 along with the Type 925-class tender 861 Changxingdao.

    This was followed by a patrol of a Type 091 SSN from December 13, 2014 to February 14, 2015.

    Next came a S-20/Type 041A Yuan-class SSK that docked at Pakistan’s Karachi port in late May 2015, and was accompanied by a Type 925 Dajiang-class submarine tender.

    From this, it can be deduced that in the years to come, the PLAN will continue with this practice of launching at the very least two annual long-distance patrols—one each by an SSN and SSK—into the IOR. Entry while remaining submerged into the IOR from either the South China Sea or the Pacific Ocean will be made through either the Lombok Strait or the Ombai Wetar Straits astride Indonesia.

    [​IMG]

    During future hostilities with either the US or India, the most likely destinations of PLAN’s SSNs within the IOR will be the area around Diego Garcia and the Chagos Trench. Diego Garcia is part of the Chagos Archipelago, situated on the southernmost part of the Chagos-Laccadive Ridge. To the east lies the Chagos Trench, a 400 mile-long underwater canyon that ranges in depth from less than 1,000 metres to more than 5,000 metres, and the most likely area where the IN’s SSBNs will be lurking during operational patrols.


    [​IMG]

    All vessels, including warships, enjoy the right of innocent passage through archipelagic waters. Innocent passage requires a vessel to conduct continuous and expeditious transit in a manner that is not prejudicial to the peace, good order or security of the archipelagic state. For a submarine, innocent passage means transiting on the surface, as is the case with the Malacca Strait. But the Lombok Strait astride Indonesia is not considered archipelagic waters, rather it is part of an Archipelagic Sea Lane (ASL) that carves a path from Lombok in southwest Indian Ocean, through the Flores Sea, the Makassar Strait, the Sulawesi and Celebes Seas and on to the Pacific Ocean. It is like this because Indonesia desires sovereignty within the archipelago beyond the normal 12nm territorial water limit, which can be granted in relation to archipelagic states in certain circumstances, provided the ASLs are designated.For a submarine, normal passage means transiting submerged. The other interesting thing about ASLs is that, unlike innocent passage through archipelagic waters, which can be suspended temporarily on a non-discriminatory basis, this is not the case for ASLs. Any PLAN submarine can legally transit Lombok dived. If it chooses to loiter illegally and then gets caught, it can feign normal passage.

    [​IMG]
    PLAN SSN route

    Unlike the Sunda Strait—which forms part of a separate ASL, but is realistically too shallow for dived passage by all but the most daring/lucky of submarine operators—the Lombok Strait is relatively deep (varying between 800 and 1,000 metres). At the southern end of the Strait, where the channel is divided by the Island of Nusa Penida, a shallow sill is located. Depths rise to between 200 and 250 metres in the channel to the east of Nusa Penida. The sill is of huge importance to the oceanographic behaviour in the Strait, particularly since the Lombok Sea serves as one of two outlets (the other being the Timor Passage) for a great body of warm water that flows from the Pacific to the Indian Ocean—the so called Indonesian Throughflow.

    This sill, coupled with the Throughflow and tidal flow, results in relatively large current flows, typically from north to south, but is sometimes reversed. Current flows near the sill can reach 3.5 metres per second during spring tide periods. In the deeper water to the north of the sill it slows to between 0.2 to 0.5 metres. It must be noted, however, that current velocities vary as a function of depth. The upper 100 metres carry 50% of the total water transport through the Lombok Strait. Current velocities are, therefore, maximum at the surface with a sharp decrease from 75 to 300 metres.These currents are a quite significant for submarine operations, particularly diesel-electric SSKs, which must conserve battery life or that cannot take advantage of the deeper areas where the current is minimal.They also create interesting and complicated acoustic conditions for sonar on account of the varying temperature and salinity gradients across the current-related layers.

    TRISHUL: DEFEXPO 2016 Show Report-2


    @abingdonboy @PARIKRAMA @Bahamut @SajeevJino @Superdefender
     
  5. SajeevJino

    SajeevJino Long walk Elite Member

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    .

    I heard a little bit about the undersea surveillance systems, but not brief like that, many thanks for the share @Gessler

    ahem anti US blah blah guys..read the above please
     
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  6. sayareakd

    sayareakd Moderator Moderator

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    India too has its own underwater and over water sensors at sea.
     
  7. Bahamut

    Bahamut Senior Member Senior Member

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    Submarine fleet has always been neglected in India even when they have more capability in a conventional conflict .Lets hope its changes.
    P 8I have increased our submarine warfare capability ,UAV armed with ASW kits can be made in India ,but I think its high time that we develop our own AIP equipped Hunter Killer Submarine ,designed and made in India.
     
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  8. AnantS

    AnantS Senior Member Senior Member

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    @sayareadkd Any references for the same?esp if we have any rudimentary sosus kind of underwater networked system in place?

    I am not keen that India should n/w with USN, because then we can forget any Russian nuke sub lease or any related tech ToT. US cant replace Russia in terms of deep tech relationship with India.
     
  9. Bahamut

    Bahamut Senior Member Senior Member

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    upload_2016-4-17_19-0-4.png
    ................................................................................................
     
  10. Gessler

    Gessler Regular Member

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    You're welcome, bro.

    Anyway, it's thanks to Prasun K. Sengupta for the detailed analysis!
     
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  11. SajeevJino

    SajeevJino Long walk Elite Member

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    we recently inaugurated a harbor underwater security system with the support of Israel

    Money can change anything .. forget the supa dupa Russian tech.. ask the veteran members about T 90 game, Smerch game and BMP 3 game played by Russia

    everyone knows that Vikky story
     
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  12. Bahamut

    Bahamut Senior Member Senior Member

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    @Gessler
    I found a good DARPA project

    ACTUV
    From Wikipedia, the free encyclopedia

    [​IMG]
    A rendering of the Continuous Trail Unmanned Vessel (ACTUV)
    The ASW Continuous Trail Unmanned Vessel (ACTUV) is a DARPA funded project launched in early 2010 to develop an Anti-submarine drone (Unmanned surface vehicle). In September 2014, DARPA signed a Memorandum of Agreement with the Office of Naval Research (ONR) to jointly fund the ACTUV prototype. If successful, the program could transition to the U.S. Navy for ASW by 2018, and possibly other missions such as mine countermeasures.[1]


    Overview[edit]
    It is stated that the ACTUV will be "a first unmanned naval vessel that is designed and sized for theater or global independent deployment". The aim of the four part program is to develop a surface vessel optimized to overtly track and trail target submarines. A suite of sensors "capable of tracking quiet, modern diesel electric submarines" will be implemented into the completely unmanned vessel.

    It is intended that ACTUV will operate under minimal supervisory command and control; with shore bases intermittently monitoring performance and providing high-level mission objectives through beyond line-of-sight communications links. The vessel will be provided with advanced autonomous navigation and anti collision features to keep it within maritime law and the International Regulations for Preventing Collisions at Sea.

    It is hoped that the unmanned nature of the vessel will open up new technologies in terms of stability and sea keeping. The four part program will culminate in an integrated prototype vessel and sea trials following evaluation and design phases.

    Concept of operations[edit]
    The ACTUV is aimed at improving the ability to detect and engage diesel-electric submarines, which are inexpensive and quieter in comparison to nuclear-powered submarines, and to negate the threat of adversaries building large numbers by creating anti-submarine tactics at one-tenth the cost of building a diesel submarine. Areas of operation are focused on littoral waters. The craft will be an unmanned surface vehicle (USV) designed to operate and patrolautonomously for 60–90 days straight, being able to hunt for targets and avoid surface ships by itself. It will operate alongside other naval assets including theP-8 Poseidon, MQ-4C Triton, and sonobouy sensors as a forward deployed and rapid-response node in the global maritime surveillance network.[2][3]

    Once a wide-area sensor provides an initial indication of a possible target, the forward deployed ACTUV will then rapidly "sprint" to the area and use its own sensors to assess the contact. First, two side pods with long-range acquisition mid-frequency active-passive sonar will verify the presence of a submarine and identify the area of uncertainty (AOU) affected by the threat to limit close surface ships' movement. Second, two higher frequency sonars in the main hull will improve tracking precision and mission reliability. Once in close proximity, total field magnetometer arrays will provide additional information about target activity to continuously track it. Finally, very high frequency sonar will produce an "acoustic image" of the target to identify and classify the specific submarine.[2][3]

    The ACTUV is to be in constant contact with other ships and aircraft through a satellite link; if a contact is determined to not be threatening, a sailor can order the vessel go back on patrol. The craft itself is unarmed, so if an enemy submarine is detected it will notify other naval assets that can attack and destroy it. If deemed not a threat, the craft can still shadow the submarine to deter it from acting aggressively, potentially even back to its home port. The ACTUV is designed to out-endure any diesel-electric submarine, even those equipped with Air Independent Propulsion (AIP).[2][3]

    Using large numbers of inexpensive unmanned ACTUVs is a way to counter submarines as an undersea component of anti-access warfare. Some countries use "competitive strategies" to create cheap weaponry, hardware, and methods to impose on their adversaries a situation where they would need to incur costs of developing countermeasures that are disproportionately higher than the defenses they would be used against. The goal is to make the adversary decide the competition is unaffordable, or force them to redirect resources from other priorities. Countries building cheap diesel-electric submarines as anti-access components would be subjected to the same cost-benefit considerations they are trying to impose, as the U.S. Navy would be equipped with an even cheaper anti-submarine detection system.[4]

    In order to comply with International Regulations for Preventing Collisions at Sea (COLREGS), the ACTUV has to autonomously identify other surface ships at sea. Radar is the primary way to sense other ships, but it is not able to classify them. To augment radar, as well as reduce reliance on it, DARPA released aRequest for Information (RFI) in March 2015 for other sensors for the ACTUV to perceive and classify nearby ships and other objects. Expected sensor systems and image-processing hardware and software include passive electro-optical/infrared (EO/IR) or non-radar active (LIDAR) technologies.[1]

    Construction[edit]
    After making Broad Agency Announcement (BAA),[5] DARPA allowed the national security, health, and engineering company Leidos to go forward with the ACTUV program in February 2014. Using a USV for submarine hunting is aimed to free up other surface ships from needing to spend time and money looking for them themselves. Leidos' model is an unmanned trimaran built out of carbon composites equipped with navigation and piloting sensors, electro-optics, and long and short range radar to be capable of tracking diesel submarines at extreme depths for months at a time. The vessel is able to report back on the situation and its condition, and has computers programmed to identify other vessels to anticipate what they will do next. It uses a modular design that can be refitted for other roles such as intelligence, surveillance and reconnaissance missions.[6]

    Leidos announced on 18 November 2014 that a test vessel fitted with autonomy software and sensors to mimic the configuration of the ACTUV completed 42 days of at-sea demonstrations to fulfill collision regulations (COLREGS). The 32 ft (9.8 m) surrogate vessel simulated scenarios where the ACTUV prototype would interact with an interfering vessel, navigating through narrow channels while avoiding obstructions and other surface ships autonomously in completely unscripted events. Follow-on testing will involve multiple interfering contacts and adversarial behaviors of interfering vessels.[7]

    The company announced on 26 January 2015 that the ACTUV autonomy software had been successfully tested off the coast of Mississippi to test sensor, maneuvering, and mission functions. Installed on a 42 ft (13 m) work boat, the autonomy system navigated the complicated inshore environment of the Gulf Intracoastal Waterway using only a pre-loaded navigational chart and inputs from commercial-off-the-shelf (COTS) radars. The surrogate vessel traveled 35 nmi (40 mi; 65 km) while avoiding all obstacles, buoys, land, shoal water, and other vessels without pre-planned waypoints or human intervention. The first ACTUV, named Sea Hunter, was scheduled to launch in late fall 2015 and begin testing in the Columbia River.[8]

    By late October 2015, building of the ACTUV was 90 percent complete, with the hardware of the systems finished and the software being engineered. Testing of the command-and-control and navigation systems to enable the unmanned boat to operate safely in compliance with maritime safety standards "generally meets expectations." The vessel is 132 ft (40 m) long, weighs 140 tons, and is expected to cost $15,000–20,000 to operate per day, compared to $700,000 per day for a destroyer. Advantages of the vessel over ship-launched USVs are that it has greater payload and endurance, and it can launch and recover at a pier rather than needing integration with a manned ship. DARPA plans to conduct testing at Point Loma, San Diego.[9] In November 2015, Raytheon delivered its Modular Scalable Sonar System (MS3) to be integrated onto the Leidos ACTUV. The MS3 is a fifth-generation hull-mounted sonar system that performs active and passive search and tracking, incoming torpedo warning, and small-object avoidance for safe navigation.[10] In addition to submarine hunting, the vessel could perform counter-mine, reconnaissance, and resupply missions.[11]

    Sea trials[edit]
    DARPA launched the ACTUV technology demonstrator on 27 January 2016 at its construction site of Vigor Shipyards in Portland, Oregon and conducted local trials through February, achieving speeds of 27 knots (31 mph; 50 km/h). It allegedly had already successfully tracked a submarine from 1 kilometre (0.62 mi; 0.54 nmi) away.[12][13] The vessel, named Sea Hunter, was commissioned on 7 April 2016. She will be sent to San Diego for a two-year trial period through September 2018, conducted by DARPA and ONR.[14]
     
  13. Bahamut

    Bahamut Senior Member Senior Member

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    An appeal for new emphasis on antisubmarine warfare
    November 1, 2004
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    Editor's note: This story appeared originally in the November 2004 print edition of Military & Aerospace Electronics.

    The global war on terrorism is focusing technological efforts on a wide variety of sensors, information processing, and data mining to deter and respond to terrorist attacks here and abroad.

    Yet, in this environment, the U.S. and its allies need to maintain their focus on what was a central component of Cold War strategy - anti-submarine warfare, otherwise known as ASW.

    I know what you’re thinking: what’s antisubmarine warfare got to do with war on terror?

    The answer may be not much today, but that certainly could change in the near future. Changing national threats, asymmetric warfare, and the proliferation of submarines worldwide make antisubmarine warfare and its sophisticated electronic and optoelectronic technologies as important today as they have ever been.

    Last summer the U.S. intelligence community received one of the nation’s loudest wakeup calls in a long time where undersea warfare is concerned. China has produced a new type of attack submarine, which U.S. intelligence did not even know was under construction, according to a report in The Washington Times.

    The new submarine that surprised U.S. military leaders was first seen and photographed in late June or July in the water at China’s Wuhan shipyard, 420 miles west of Shanghai, The Times reported. Pentagon leaders are calling the new Chinese vessel the Yuan-class of submarine.

    Intelligence experts say they believe the Yuan-class submarines are diesel powered, and are a combination of Chinese-developed hardware and Russian weapons. Modern diesel submarines are extremely quiet and difficult to detect, even with the most sophisticated U.S.-developed sonar systems.

    The Yuan class joins China’s deployed force of 57 submarines, and two nuclear-powered submarine classes in development - the Type 093, which intelligence analysts believe is based on the Russian Victor III ballistic missile submarine, and the Type 094 attack submarine.

    These developments are conclusive evidence that China is serious about maintaining a formidable offensive naval capability in the Western Pacific, not only to project its regional influence, but also to counter U.S. force projection from nuclear-powered aircraft carriers in the strait that separates Taiwan from China.

    The U.S. considers Taiwan to be a pseudo-independent country, and has pledged to protect Taiwan from military threats. China, however, considers Taiwan to be a rogue province, and has pledged to bring the island back under Beijing’s control. This geopolitical hotspot underscores the need for ASW technology.

    U.S. antisubmarine warfare programs are in a state of flux after a decades-long focus on open-ocean military confrontation with an industrialized opponent such as the Soviet Union. Today’s U.S. naval focus is making the transition to relatively shallow coastal waters - the so-called “littoral” environment.

    Although littoral naval warfare involves a great deal of ship-to-shore communications networking, mine detection, and sea-to-shore missiles and gunfire, the coastal shallows represent some of the toughest challenges for ASW operations.

    Whereas the open oceans often present a deep, vast area where picking out submarines from a comparitively quiet background is relatively straightforward, the littoral areas represent a whole different ball game.

    The shallows represent a sonically diverse environment; these areas team with sea life, many commercial and military vessels operate there, sound waves bounce erratically off the bottom, and shipwrecks or rock formations can be easily mistaken for hostile submarines.

    Add the tremendously quiet modern diesel-electric submarine to this mix, and antisubmarine warfare throughout the world becomes much more difficult than it has ever been before.

    Despite this challenge, U.S. ASW capabilities are “at a historic low” because of cutbacks in specialized ships and aircraft, The Times quotes Richard D. Fisher Jr., a specialist on the Chinese military at the James Foundation, a Washington-based think tank.

    The worldwide submarine threat does not come only from China. The breakup of the Soviet Union helped create a surplus of submarines that became available for sale. Today Iran, North Korea, Libya, Egypt, Pakistan, India, and Turkey are only a few of the nations that operate submarines.

    Arms exporters in Europe and elsewhere also are eager to offer submarines on the world arms market as a major source of income. Put simply, submarines are becoming easier to obtain all the time, not only by developing countries, but by terrorist organizations as well.

    The “asymmetric” nature of modern warfare makes the submarine threat even more urgent. Terrorist networks with ready access to cash are increasingly likely operators of submarines, with which they could wreak havoc on oil-tanker traffic in the Persian Gulf, or perhaps even destroy or disable an unsuspecting U.S. capital ship such as an aircraft carrier.

    The current U.S. military emphasis on force transformation and network-centric warfare has broad potential to help improve antisubmarine warfare capabilities. The application of networking technologies could make information on enemy submarine positions available instantly not only to military forces, but also to homeland-security forces such as the Coast Guard, and to commercial shipping companies.

    Optoelectronic technologies such as fiber-optic sonar and laser radar have the potential not only to help cut through the sonic murk of coastal waters, but also to network sonar detectors in real time to yield quick information on enemy submarine speed, depth, and direction of travel.

    Yet none of this will happen without a serious commitment of technological expertise, research, and money to the problem of antisubmarine warfare.

    There are indications that the nation’s ASW community is waking up to the new ASW challenge. The Government Electronics and Information Association (GEIA) Ten-Year Forecast in October highlighted undersea sensors as one crucial need of the U.S. Navy.

    “The Navy lacks undersea sensors, and seeks better sensor technology,” said Gerry Robbins of Northrop Grumman Corp. in his information-technology presentation at the GEIA forecast in Vienna, Va.

    Another indication: Navy leaders in September asked permission from the Swedish government to borrow a Gotland-class conventionally powered Swedish submarine and its crew for ASW training. If the plan is approved, the Swedish submarine would be based at the Navy Fleet Anti-Submarine Warfare Command in San Diego.

    With the growing submarine threat from often-undetermined adversaries, let’s hope this renewed emphasis on ASW technology isn’t too little, too late.
     
  14. Bahamut

    Bahamut Senior Member Senior Member

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    Chinese Submarines and U.S. Anti-Submarine Warfare Capabilities
    ELENI EKMEKTSIOGLOU AND MATTHEW HALLEX, AUG 27 2011, 5156 VIEWS
    China’s military modernization has been a source of great concern for the United States and its allies in the Asia-Pacific region. American anxiety has been fueled by double digit defense budget increases over the last decade along with the veil of mystery that covers Chinese defense spending. Much of these funds have been devoted to the acquisition of platforms and weapons that will allow China to implement Anti-Access/Area Denial strategies (A2/AD.)[1] Despite the growth of Chinese economic and military power, it is in no position to challenge the United States and in particular the U.S. Navy on equal footing.

    Sea control in the face of U.S. maritime power is still beyond the People’s Liberation Army Navy (PLAN) but sea denial is an achievable goal.[2] Sea denial aims not to eliminate U.S. naval forces but drawing on the same toolkit as insurgents, aims to inflict unacceptable costs on enemy forces and erode their political will to continue fighting.[3] Such a strategy relies upon an asymmetric approach – confronting U.S. surface forces with PLAN surface forces would serve to play to the strengths of the United States. Rather, the PLAN aims to inflict unacceptable costs by focusing on the weaknesses of the United States. Multi-layered Chinese systems, threatening U.S. forces from the land, the surface, the air, and under the waves could threaten to deny access to key strategic areas to the United States.

    Submarines, unsurprisingly, can be expected to play a significant role in Chinese asymmetric A2/AD strategies.[4] The inherent stealth of submarines makes anti-submarine warfare (ASW) one of the most difficult tasks facing a modern navy. This challenge is complicated further by Chinese acquisition of new nuclear (SSNs) and advanced conventional submarines (SSKs.) When armed with advanced torpedoes, sea mines, and anti-ship missiles, even relatively unsophisticated submarines can pose a significant threat to U.S. surface forces, including the aircraft carriers that are the heart of the U.S. ability to project power into the Western Pacific region.

    This paper will address the role submarines are likely to play in Chinese maritime strategy. It will review the structure of the Chinese submarine force and procurement trends that are shaping its future structure. China has identified a growing gap in U.S. military capabilities since the end of the Cold War and this paper will identify some of the operational uses and missions of submarine the PLAN will likely use to exploit it. The paper will also review current weaknesses in U.S. ASW capabilities, efforts currently underway to address them, and conclude with suggestions of further steps that should be taken to improve the ability of the U.S. to properly exploit the undersea domain.

    Chinese Submarine Forces

    Modernization and expansion of the submarine fleet has been a high priority for the People’s Liberation Army Navy. Acquisitions from abroad as well as a number of indigenous development programs have added advanced conventional and nuclear submarines to China’s fleet. In addition to bolstering the number of vessels deployed by China, the acquisition of new weapons systems have made Chinese forces a more potent threat to U.S. and allied forces in the region.

    Force Size

    While China has maintained a number of obsolete vessels in service, procurement in recent years has been focused on replacing outmoded vessels and increasing the size of the force. According to the Congressional Research Service, the PLAN’s annual commissioning rate of 2.6 submarines of all types will eventually result in an undersea force of 53-79 submarines.[5] The final size of the submarine force will depend upon China’s choice of deploying large numbers of less costly diesel-electric submarines or acquiring a smaller force of nuclear submarines.

    Platforms

    Beginning in the 1990s, China undertook an extensive modernization of its submarine force. Initially, the PLAN focused on acquiring advanced submarines from abroad and purchased 12 Kilo class submarines from Russia in 2002. In addition to foreign acquisitions, China has indigenously developed four classes of submarines including a nuclear ballistic missile submarine (Type 094/Jin-class), a nuclear attack submarine (Type 093/Shang-class) and two classes of conventional diesel electric submarines the Song and Yuan classes.[6] The Yuan class is believed by many analysts to be equipped with an Air Independent Propulsion (AIP) system which would significantly improve its stealth capabilities.[7]

    In addition to the new submarines that have been fielded, China is developing two additional submarine classes that represent steps towards a sophisticated submarine force. China seems determined to develop an improved version of its indigenously produced Shang class nuclear attack submarine. According to the U.S. Office of Naval Intelligence report, this improved attack submarine is expected to enter service in 2015.[8] An improved variant of the Yuan class is also under production. This variant is reported to be notably different from its predecessors and incorporates a number of features from the Kilo class submarines acquired from Russia.[9]

    Weapons Systems

    Procurement of advanced weapons systems is key to making China’s newly acquired submarines an effective fighting force, in addition to boosting the combat capabilities of China’s current forces. Chinese submarines are equipped with wake-homing-torpedoes which can threaten U.S. surface forces. Kilo-class submarines are equipped with the SS-N-27 Sizzler anti-ship missile. The Sizzler is a supersonic sea skimming missile designed to defeat the Aegis missile defense system deployed by the U.S. Navy.[10] The Yuan and Song class submarines are expected to be equipped with the new CH-SS-NX-13 anti-ship missile when it completes development and testing. As well as being able to threaten U.S. surface vessels, Shang class submarines are capable of firing land attack cruise missiles that would allow it to threaten bases in the region and other infrastructure that support U.S. power projection in the Western Pacific.

    The Chinese Submarine Force in the Context of a Sea Denial Strategy

    Chinese procurement trends suggest a preference for smaller and stealthier submarines rather than long-range endurance platforms. While China is moving towards a blue water navy, it is capitalizing on advantages conventional submarines present to green water navies. Conventional submarines, particularly those equipped with AIP systems, can operate with a greater degree of stealth and freedom in the waters near China than larger U.S. nuclear submarines. Advanced weapons systems deployed on submarines along with land based missile and air forces would serve to deny the waters near the Chinese coast to U.S. and other combat forces.

    While U.S. submarines play an important role in ASW activities, Chinese operational planners seem to focus more on the development of anti-surface warfare (ASuW) doctrine enabled by stealthy conventional submarines. Through the purchase and indigenous production of quiet diesel-electric boats, China intents to create a ‘ghost’ submarine force that would move silently along the Chinese coast looking for possible surface targets while avoiding encounters with the enemy’s submarine force. The difficult underwater geography of the littoral region as well as the noise from coastal shipping, fishing, and other economic activities make it an ideal operating environment for China’s submarines. Chinese investments in hydrographic studies enhance its knowledge of the underwater topography, thermoclines, and other elements of the coastal area and would allow the PLAN to take full advantage of the opportunities offered by the Chinese coastal operation theater. [11]

    While Chinese operational plans and possible missions for their submarine force remains opaque to outside analysts, the limitations of their current systems suggest that submarine forces are unlikely to operate independently. Rather, as Admiral McVadon suggests in the Naval War College Review, Chinese submarine forces would work in coordination with shore based missile systems.[12] Given that older Chinese submarines would encounter difficulty attempting to penetrate U.S. ASW defenses to conduct anti-surface strikes under normal conditions, the PLAN would be more likely to wait until missile strikes launched from the mainland had degraded U.S. missile defenses before launching anti-ship missile and torpedo attacks.

    The supersonic Sizzler ASCM fired by Kilo class submarines could threaten U.S. surface forces if launched in sufficiently numbers, or if a Kilo managed to surprise its target.[13] The subsonic missiles and torpedoes carried by the rest of the Chinese submarine fleet would be easier for U.S. forces to defeat but they could still pose a significant threat to U.S. surface vessels after U.S. defenses were degraded by other attacks. Older submarines including the Ming, Romeo, and Han class vessels based on obsolete Soviet designs, can also pose a threat. Such submarines could act as mine layers or as bait, bringing in U.S. submarines and ASW forces into the range of missiles carried by more advanced Chinese submarines.

    The technological developments undertaken by the Chinese submarine force have had an impact on the PLAN’s assessment of their own capabilities and roles. The Kitty Hawk incident, in which a Chinese submarine surfaced in the midst of a U.S. carrier battle group, suggests that Chinese submariners are confident in their ability to avoid detection by U.S. ASW escorts.[14] Such incidents as well as an increasing number of submarine patrols suggest that China aims at operating its forces further afield in the region and sending the message across that China is a non- negligible maritime power in the Asia Pacific.[15]

    The United States and the Chinese Undersea Challenge

    While the submarine forces of the PLAN have expanded and improved their technological capabilities, the ASW capabilities of the United States have eroded. Throughout the Cold War the United States faced a persistent threat from Soviet submarines and ASW was to be a primary mission of the U.S. Navy during a conflict as it attempted to eliminate Soviet sea based nuclear forces and ensure that sea lanes to NATO allies in Europe remained open. The fall of the Soviet Union eliminated the undersea peer threat to the United States and ASW has not been a major component of U.S. naval operations in recent conflicts. The U.S. has retained qualitative and technical superiority in the undersea domain but ASW capabilities have suffered in recent decades.

    Much of the difficulty faced by U.S. ASW forces stems from the technical challenge posed by the stealth of advanced conventional submarines. Conventional submarines operating on battery power have a smaller passive sonar signature than nuclear submarines which must keep their reactor machinery operating. AIP systems serve to extend the period in which SSKs can operate quietly making them more capable and more difficult to detect.

    In addition to the technical challenge posed by modern conventional submarines forces, the balance of undersea forces in the Pacific is shifting. While the PLAN expands its submarine forces, U.S. naval forces are drawing down. The current shipbuilding plan of the U.S. Navy envisions a reduction in submarine forces to a fleet of only 39 nuclear attack submarines in 2030, significantly less than the 48 that the Navy projected as necessary to fulfill future missions.[16] While U.S. submarines are unmatched technologically, their low numbers will be a significant shortcoming due to the heavy demands that would likely be placed on them to perform both strike and ASW missions during a potential conflict between the U.S. and China.

    Other shortfalls in U.S. ASW capabilities can also be expected. Anti-submarine warfare is a planned mission for the Littoral Combat Ship (LCS), a program which has proven to be deeply troubled. Currently deployed LCSs have developed significant problems with structural damage due to corrosion. The LCS also lacks organic ASW capabilities and is not equipped with the towed sonar array found on previous dedicated ASW combatants. Rather, the LCS can be equipped with an ASW mission module when necessary that is projected to include unmanned undersea vehicles (UUVs) and unmanned aerial vehicles (UAVs) that can carry out ASW missions. The LCS mission modules are facing a number of development hurdles and are significantly behind schedule.[17] U.S. aerial ASW capabilities have similarly eroded. The U.S. retired the S-3 Viking leaving U.S. carriers without a fixed wing ASW capable aircraft. While the U.S. is replacing its P-3 Orion maritime surveillance and ASW aircraft with the advanced P-8, such aircraft must operate from land bases. While the P-8 will likely be a highly capable ASW combatant, the bases it operates from would be highly vulnerable to the types of missile and air attacks that would be integral to a Chinese A2/AD strategy.

    While the U.S. Navy faces significant challenges in the ASW arena, it has taken a number of steps to cope with the increased threat posed by Chinese and other submarines. U.S. naval forces in the Pacific have placed a renewed emphasis on ASW training. As part of an effort to build greater familiarity with conventional submarines equipped with AIP systems the U.S. conducted two years of training with the Gotland, an advanced Swedish diesel submarine.[18] Such training continues as part of the Diesel Electric Submarine Initiative which involves regular training exercises involving U.S. ASW forces and the conventional submarines of allies.[19] While this training is a step in the right direction, exercises have demonstrated that advanced diesel submarines are highly capable threats that can threaten major U.S. surface combatants.

    Shipbuilding shortfalls are unlikely to be improved due to expected future cuts in the U.S. defense budget and the significant problems that plague current U.S. navy procurement efforts. The U.S. has coped, in part, by shifting its current forces to better face the threat posed by expanding Chinese capabilities. The U.S has permanently home ported four Los Angeles class submarines and a tender in Guam and shifted other submarines to bases in Hawaii and California.[20] The U.S. is also planning to base future LCSs in forward bases in Singapore.[21]While forward deployment does risk putting the infrastructure supporting U.S. ASW forces within range of Chinese missile systems, it would also reduce the transit time for U.S. forces, allowing them to deploy more quickly and remain in theater longer during a conflict.

    The shortcomings in China’s own ASW capabilities would allow U.S. submarine forces to disrupt Chinese attempts to project power in the region and threaten PLAN surface forces. Cruise missile armed U.S. submarines would also play an important role in strikes against targets within China. During Desert Storm just 10% of missile strikes came from subs, while one third of such strikes were launched from submarines during the conflicts in Afghanistan and Iraq.[22] The conversion of Ohio class ballistic missile submarines to guided missile submarines (SSGNs) has expanded this capability further. U.S. submarines represent a power projection force that is relatively immune to Chinese A2/AD capabilities as they can’t be threatened by air and missile forces and China currently lacks ASW forces to credibly threaten them. While the striking abilities of U.S. undersea forces will be diminished by the retirement of Ohio class SSGNs, they represent a threat that the PLAN lacks the ability to credibly respond to.

    Recommendations for the United States

    Shifting submarines forces to the Pacific and increasing ASW training is an important first step in responding to the challenge posed by China’s expanding and improving submarine forces. However, it is insufficient. There are a number of steps the United States could take to improve the undersea balance of power in the Asia Pacific region. Submarines are a vital asset which can serve as the primary ASW tool for U.S. naval forces, and which can carry out strike missions without interference from Chinese A2/AD systems. Addressing the shrinking size of the U.S. fleet is vital. The U.S. Navy should continue its efforts to improve the cost effectiveness of its current procurement programs and consider shifting a larger portion of the shipbuilding budget to submarine acquisition. In particular, the U.S. should procure additional guided missile submarines to replace retiring Ohio class SSGNs and to expand the ability of the U.S. to strike targets despite China’s deployment of A2/AD systems.

    The United States should also invest in new technical solutions that could bolster American ASW capabilities. Unmanned surface and underwater vehicles are increasingly capable and further development in this area would provide alternatives to expensive and vulnerable manned assets. Ships deploying a number of unmanned sensors from a standoff distance would be better able to detect stealthy submarines while being less vulnerable to Chinese missile attacks. Deploying fixed sensors in strategic points in the waters near China would also improve the ability of the U.S. to detect PLAN submarines. During the Cold War fixed acoustic sensors deployed between Greenland, Iceland, and the United Kingdom allowed U.S. forces to detect Soviet submarines as they entered the North Atlantic. Similar systems could serve as tripwires for the entrances to the Western Pacific from the South China Sea. The cooperation of Vietnam and the Philippines would be required for the deployment of the shore based support infrastructure, but as Chinese naval deployments grow more threatening, the support of these states is more likely to be forthcoming.[23]

    Some analysts have suggested that the United States should develop conventional submarines of its own.[24] Conventional powered submarines could be less expensive to procure than current nuclear vessels and their small size and stealthy capabilities would be better suited for operating in the Chinese littoral. Despite the potential tactical and financial advantages that conventional submarines offer, the United States should continue to deploy a nuclear attack submarine force. The U.S. lacks the industrial base to construct conventional submarines and acquisition from foreign suppliers would be politically difficult. Nuclear submarines are also capable of faster transits from bases in the United States, Hawaii, and Guam to the Western Pacific, which could be vital in a crisis. The larger size and power of nuclear submarines also allow them to support more complex sensor systems which are increasingly necessary for ASW work.

    Conclusions

    PLAN submarines play an important role in Chinese A2/AD strategies. While they are not as novel of a threat as anti-ship ballistic missiles, their numbers and increasing sophistication pose a severe threat to shrinking U.S. submarine and surface forces. China’s submarine force is likely to expand in the future and develop increasing long-range and blue ocean capabilities that can attempt to push U.S. forces further from Chinese home waters. The United States must invest to maintain the superiority of its undersea forces and to relearn and redevelop the core ASW capabilities it lost following the end of the Cold War and the Soviet submarine menace. Beyond ASW, submarines also represent a capability that is relatively immune to Chinese A2/AD strategies. The ability of U.S. submarines to operate in environments too dangerous for surface ships should be a serious consideration in future procurement and investment decisions.

    Eleni Ekmektsioglou is a Handa Fellow at Pacific Forum CSIS. She holds a Masters degree from King’s College London War Studies Department.

    Matthew Hallex is a graduate of the Security Policy Studies Masters program at George Washington University. He focused on Asian regional security and weapons of mass destruction.
     
  15. warrior monk

    warrior monk Regular Member

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    upload_2016-4-17_21-4-31.png upload_2016-4-17_21-5-39.png

    upload_2016-4-17_21-4-31.png



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    JGSDF Coastal Surveillance Unit 301, Wakkanai, (7-element CDAA for HF/VHF interception and DF), 16 August 2010




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    JMSDF ELINT/undersea surveillance station, Tappi Zaki

    US SOSUS Stations
    The US Navy was interested in Japanese locations for its SOSUS (sound surveillance system) stations from the beginning of its SOSUS program, initially called Project Caesar, which involved running cables out on continental shelves and connecting them to hydrophones suspended above the sea bottom at optimum signal depths. An ‘experimental station’ was established at the north-western tip of Hokkaido in 1957, with the cable extending into the Soya (La Perouse) Strait. It monitored all the submarine traffic going in and out of Vladivostok and Nakhodka in the Sea of Japan.1 What was heard, however, ‘didn’t make sense because the collection of ship and submarine signatures was in its infancy at that time. It was a jumble of sounds’.2 The jumble of sounds ‘was largely undecipherable by existing signal processing’.3
    Undersea surveillance systems and associated shore-based data collection stations code-named Barrier and Bronco were installed in Japan in the 1960s. These were reportedly similar to the Caesar system installed around the coasts of the United States but were ‘located in coastal waters of friendly nations’. Acoustic data collected at these sites was transmitted by US defence communications satellites to US Navy processing and analysis centres in the United States.4 According to a former US Navy intelligence officer:

    In the mid-1960s we offered to extend the CAESAR system to friendly countries ‒ those that would allow CAESAR terminals to be installed as part of the Navy’s overall world network. In Great Britain and Japan, systems were installed in the shallow coastal areas which had proven over the years to be the favorite exit points for Soviet submarines proceeding to the high seas. In 1967 there was congressional debate about extending CAESAR overseas, but testimony allayed Congressional fears that control of the system would slip beyond the Navy’s reach.

    The arrangements for assuring United States control evidently included stationing of US Navy personnel at the shore stations as well as the provision of satellite communications (Satcom) systems for the transmission of the acoustic data back to the United States.
    There have been numerous reports about the locations of the US SOSUS stations in Japan. For example, a report prepared for the Committee on International Relations of the US House of Representatives in 1978 referred to a SOSUS array ‘between Japan and Korea’.6 An article on US and Allied SOSUS systems in 1980 identified three stations, at Wakkanai (designated JAP-4), Tsushima (JAP-108) and the Ryukyu Islands (RYU-80);7 by this time the United States no longer had any SOSUS system in the Soya Strait, but relied on the Japanese station at Wakkanai to provide relevant information about the passage of Soviet submarines in that area. A map published in Scientific American in February 1981 also showed SOSUS shore facilities in the Tsushima Straits and the Okinawa area.8 The existence of old cables at Horonai Point in north-west Honshu, which during the Cold War led out to SOSUS arrays in the Sea of Japan, has been widely described by scuba divers.9 A study of US technical intelligence systems published in 1986 claimed that SOSUS hydrophone arrays stretched ‘from southern Japan to the Philippines, covering the approaches to China and Indochina’.10 The presence of SOSUS arrays sited off Okinawa was also reported in 1990.11
    After the collapse of the Soviet Union and the decline of the submarine threat to the United States in the early 1990s, the US Navy allowed its SOSUS systems in the north-west Pacific to atrophy, although some arrays were retained in working order so as to support civilian scientific research (such as tracking whales and monitoring undersea volcanic activity). According to a navy directive issued in August 1994, all ‘fixed arrays’ in the Pacific were supposed to be placed on ‘hot standby’; personnel would ‘not be routinely assigned to monitor fixed array

    data’ unless that data was required for operational purposes, but in practice the probability of being able to reconstitute them to full operational status was ‘extremely low’.12
    A decade later, however, in the early 2000s, facing an increasing Chinese submarine force and more aggressive Chinese submarine activities, the US Navy decided that it needed a new, more modern chain of fixed arrays designed primarily to monitor the movement of Chinese submarines between the East China Sea and South China Sea on the one hand, and the Pacific Ocean on the other hand. Described by an officer of the Taiwanese Military Intelligence Bureau in 2005 as the US Navy’s ‘Fish Hook Undersea Defense Line’, it would stretch from Japan southwards to South-East Asia, with key nodes at Okinawa and Guam, another Cold War SOSUS site, and would utilise Allied undersea surveillance systems (most importantly, those of Japan and Taiwan) for key sections. Beginning from near Kagoshima in the south-west part of Kyushu, it would run down the Osumi archipelago to Okinawa, then to Miyako-jima and Yonaguni in the southern part of the Ryukyu Islands, past Taiwan to the Balabac Islands in the Philippines, to Lomkok in the eastern part of the Indonesian archipelago, across the Sunda Strait between Java and Sumatra, and from northern Sumatra to the Andaman Islands. Three major gaps, between Yonaguni and Suao in north-east Taiwan (120 kilometres), between Kaohsiung in south-western Taiwan and the Dongsha (Pratas) Islands (450 kilometres) where the East China Sea meets the South China Sea, and across the Bashi Channel (220 kilometres) between Hengchun at Taiwan’s southernmost tip and Luzon Island in the Philippines, were identified around Taiwan (see Map 4).13
    It seems that the US Navy installed a new SOSUS system, stretching from Sasebo down to Okinawa, in 2006, when the US cable-laying ship USNS Zeus operated together with oceanographic survey vessels and nuclear submarines in this area.14 In July 2013, Beijing media reported that the United States and Japan had recently jointly established ‘very large underwater monitoring systems’ at the northern and southern ends of Taiwan. One of these stretched from Yonaguni to the Senkaku Islands (about 150 kilometres), while the other covered the Bashi Channel down to the Philippines. In addition, large numbers of hydrophones had been installed ‘in Chinese waters’ close to China’s submarine bases.
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    The US ‘Fish Hook’ Undersea Defense Line upload_2016-4-17_21-11-50.png




    JMSDF ELINT/Undersea Surveillance Stations

    The Japanese Maritime Self-Defense Force (JMSDF) has at least 14 listening stations serving as shore terminals for the underwater hydrophone arrays, but which are typically also equipped with marine surveillance radars sites and electronic intelligence (ELINT) collection systems, and sometimes also with optical observation equipment. A report released by the Council on Security and Defense Capabilities in June 2004 identified 12 ‘coastal surveillance and intelligence collection’ stations (including those at Rebun Island, Wakkanai and Shibetsu in northern Hokkaido identified with Japanese Ground Self-Defense Force (JGSDF) units).1 The report did not, however, include the two ocean observation stations maintained by the Oceanographic Command, which have both been widely reported in other Japanese sources as having sound surveillance systems (SOSUS). Nor did it include Hachinohe, which was reportedly equipped with an LQO-3 system around 1970, but which may no longer be operational. Some of the Coastal Defense Stations established for harbour defence in the 1950s have been closed, such as one that was built at Awaji, in Osaka Bay, in 1957 but was closed in 1987, and another at Kogozaki, at the entrance to Sasebo Bay, which was opened in March 1959 and closed in June 1990.
    The 14 identified operational stations are located at Noshyappu, at Wakkanai, at the tip of the cape that defines the southern side of the Soya Strait; Rebun Island, in the western approaches to the Soya Strait; Shibetsu, covering the eastern approaches to the Sea of Okhotsk and northern Hokkaido; Matsumae and Shirakami Saki, on the south-western point of Hokkaido, protruding into the Tsugaru Strait; Tappi Zaki, on the Tsugaru Peninsula in north-west Honshu, directly across the Tsugaru Strait from Shirakami Saki; Higashidori, on the Shimokita Peninsula; Kannon Zaki, at the entrance to Tokyo Wan (Bay); Kii, in Wakayama Prefecture, at the entrance from the Pacific Ocean to the Kii Strait and Osaka Bay; Mutsure-jima, at the western entrance to the Kanmon Strait and the Inland Sea; two stations on Tsushima Island (one on each of the North and South islands); Wakamiya, at the northern end of Iki Island, between Tsushima Island and Kyushu; and at the Ocean Observation Facility at White Beach on Okinawa

    JMSDF ELINT/undersea surveillance sites
    Site
    Comments
    1. Rebun Island, Hokkaido
    JGSDF 301st Coastal Surveillance Unit.
    2. Noshyappu, Wakkanai, Hokkaido
    A single LQO-3 system installed around 1971.
    Replaced by an LQO-3A system in the early 1980s.
    JGSDF 301st Coastal Surveillance Unit.
    301st Unit maintained a 36-element CDAA from 1988 to 2009. Replaced by a 7-element CDAA in 2009.
    Also 301st Unit at Maruyama, established in 1981.
    3. Shibetsu, Hokkaido
    JGSDF 302nd Coastal Surveillance Unit.
    Maintained a 36-element CDAA at Higashi Nemuro from 1991 to 2010. Replaced by a 7-element CDAA at JASDF SIGINT site at Nemuro in 2010.
    Associated unit at Rausu.
    4. Matsumae, Hokkaido
    New HQ building opened in 1968.
    New cable installed in 1971.
    Expanded and upgraded in 1990–91.
    US Navy team in the 1980s and 1990s.
    5. Matsumae/Shirakami, Hokkaido
    LQO-3 system installed in 1968.
    Replaced by an LQO-3A system in the early 1980s. Replaced by an LQO-4 system
    c. 1984.
    6. Tappi Zaki, Aomori Prefecture, Honshu
    LQO-3 system installed in 1968.
    Replaced by LQO-3A system in 1981–82. Replaced by an LQO-4 system around 1984.
    7. Shimokita Peninsula, Higashidori, Aomori Prefecture
    Shimokita-hanto Ocean Observation Station, Higashidori.
    Maintained by the JMSDF’s Oceanographic Command.
    8. Hachinohe, Aomori Prefecture
    A single LQO-3 array reportedly installed in the 1970s.
    9. Kannon Zaki, Tokyo Bay
    10. Kii, Hino-misaki, Wakayama Prefecture
    Kii Guard Station became operational in December 1975.
    Probably initially equipped with an LQO-3
    system, later replaced by an LQO-3A system.
    11. Kami-tsushima, Tsushima Islands
    LQO-3 system installed in 1968. Replaced by an LQO-3A system in the early 1980s. Replaced by an LQO-4 system around 1984.
    12. Shimo-tsushima, Tsushima Islands
    LQO-3 system installed in 1971–72. Replaced by an LQO-3A system in the early 1980s. Replaced by an LQO-4 system around 1984.
    9. JMSDF ELINT/Undersea Surveillance Stations
    57
    13. Mutsure-jima, Shimonoseki, Yamaguchi
    Opened on 1 December 1957. Operated remotely from Shimonseki Guard Station. Surveillance radar installed in 2010.
    14. Wakamiya, Iki Island
    LQO-3 system installed in 1968. Replaced by an LQO-3A system in the early 1980s. Replaced by an LQO-4 system around 1984.
    15. Kogozaki, Sasebo, Kyushu
    Kogozaki Coastal Defense Station, Sasebo.
    US Navy anti-submarine net, 1945–59.
    US Navy — JMSDF Coastal Defense Station, March 1959 to May 1969.
    Returned to Japan in May 1969.
    Closed in June 1990, but buildings still maintained until the early 2000s. A Zeni Lite oceanographic navigation system installed in 1993.
    16. White Beach, Katsuren, Okinawa
    White Beach Ocean Observation Station, Katsuren.
    Maintained by the JMSDF’s Oceanographic Command.
    17. Yonaguni
    JGSDF Coastal Surveillance Station under construction, to be operational in 2015. A hydrophone array reportedly installed around.
     
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  16. warrior monk

    warrior monk Regular Member

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    US Fish hook is a part of US seaweb program

    [​IMG]


    [​IMG]

    [​IMG]



    [​IMG]

    [​IMG]

    [​IMG]
    USN Blue Fin 21

    [​IMG]

    Signapore UNET

    [​IMG]

    REMUS 600 drone

    Courtesy USN
     
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  17. warrior monk

    warrior monk Regular Member

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    [​IMG]

    Chinese reclamation in Spratly Islands


    upload_2016-4-17_21-23-25.png
    Seaweb repeater node
    Seaweb telesonar modem, circa 2000-2005Benthos, Inc. COTS hardwareTexas Instruments TMS320C5410 DSPUS Navy firmwareSpectral bandwidth = 5 kHz (9-14 kHz)SL = 174 dB re 1 μPa @ 1mModulation = MFSK128 tones, 1 of 4 tones keyedForward Error CorrectionRaw bit rate = 2400 bit/sUtility packets = 150 b/sData packets = 800 b/sDI = 0 dB (omni)DI = 0 dB (omni)

    upload_2016-4-17_21-23-49.png
    Depth to Range graph

    upload_2016-4-17_21-24-18.png

    SNR ratio

    upload_2016-4-17_21-24-51.png

    mSea Eagle ACTD is demonstrating connectivity


    Multi-Access Collision Avoidance (MACA)
    Internet Protocol (IP)
    upload_2016-4-17_21-26-37.png

    upload_2016-4-17_21-27-22.png
     
  18. warrior monk

    warrior monk Regular Member

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    Courtesy - USN , The Tools of Owatatsumi and Think tanks where Prasun Sengupta also copied from.
     
  19. LETHALFORCE

    LETHALFORCE Moderator Moderator

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    This will turn the string of pearls into a noose around the Chinese neck


    Sent from my iPhone using Tapatalk
     
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  20. PARIKRAMA

    PARIKRAMA Ek_Dum_Burbak

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    @Gessler
    For you and to elaborate a bit more on PSK article..

    This i had posted in PDF as the possible high level of cooperation between India and Japan. I am sure Indian planners would be very much interested in such a network

    I had said 2 areas where India should seek Japanese help

    one is this

    Research of advanced underwater acoustic communication network technology (warships equipped Research Institute)
     In comparison with the strong radio wave propagation of linearity, the sea of sound wave is refracted in accordance with the change in the water temperature and water pressure, and propagate in a complex path. In such in order to stretch the communication distance in the horizontal direction underwater digital communication using a sound wave, it is necessary to suppress the influence of multiple reflection in the sea surface and the seabed.
     Therefore, in this Institute, suppressing the influence of multiple reflection, we conduct research on advanced underwater acoustic digital communications that enables telecommunications.

    [​IMG]

    The other is

    Research the next generation of warning and control radar (electronic equipment Institute)
     We aim to further improve the performance of warning and control radar necessary to support the future of stealth machine and ballistic missiles. Unlike previous performance improvement by the size of the antenna, the small size of the antenna and distributed, while suppressing each of the apparatus scale, we are studying a distributed radar to achieve a large-scale radar equal to or higher than that of the detection performance . We apply the most advanced MIMO (Multi-Input Multi-Output) Radar techniques to achieve equivalently large antenna optimally combining signals from a plurality of small antennas.

    [​IMG]

    The above figure works best for 5th gen jets and is a way of anti stealth missile defense capability.

    source is this government website of Japan
    http://www.mod.go.jp/trdi/saiyou/kenkyu.html

    Further the first case with all mediums for detection purposes.
    upload_2016-4-17_23-13-49.png

    http://www.mod.go.jp/atla/ats2015/image/pdf/P12.pdf



    Interestingly, i believe USA would ask India for foundation agreements for such a technology and capability sharing by Japan.

    But its a very good and solid network of detection capability.
     
  21. AnantS

    AnantS Senior Member Senior Member

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    But that does not sound that we have SOSUS kind of n/w near Indian coastal waters


    India doesnt have money to buy America off! Niche Area technology is still being denied to India. Under DTTI only low tech items are being offered which India is not even sure if it wants! The high tech are still being denied.

    http://www.tribuneindia.com/news/nation/india-us-not-on-same-page-on-tech/223013.html

    America has been dreaming to cut India to a size which suits USA. NPT, CTBT, PTBT, FMCT, MTCR, NSG are esp designed by US and its coterie to not allow countries like India ever pose challenge to them.

    Russia is no saint agreed. And it has twisted India, to get maximum money, when India had no options. So does India, when Russia finds itself in another economic quagmire. And agreed Russian Tech is behind US tech in some areas. But currently Russia is the only country which supplies high tech items which no one else can. Case in Point: Nuke Reactors, Cryogenic Engine Designs. Brahmos, hypersonic Brahmos, Akula and Another Akula class on Anvil, Reactor Tech for Arihant, Jet Engines(Barring metallurgy know-how for hot section !?) etc. And all of the above India was able to get without compromising on its sovereignty.

    And finally, India will never be an ally of US with same level as Britain. Yet Britain, herself complains of tech denial by US on critical things. Or Take case of South Korea. Remind me from where did they get the rocket engines for their new space vehicles. Hint it was not American.

    And why we should not join American Sosus n/w, is simply because we will be willingly exposing signatures of our subs Arihant or Russian Nuke Subs to US. Russia will never like that. And we can kiss goodbye to future nuke submarine lease, or access to latest nuke reactor tech from Russia.

    Reading media reports in 80-90 period would make Indian people feel obliged to USSR. Today, after reading/seeing media reports, Indian people feel obliged to US. But most people forget, both countries were/are master in social engineering. They knew/know how to sway public opinion to their favor.

    See idea is not to become Russia Bhakt, US Bhakt or Israel Bhakt. The whole idea is to be India first Bhakt. US's intentions are muddy. And they should be because, every country looks out for its interests. US is numero uno. And US knows Chinese strengths and weakness. But it shouts China wolf, only to drive other countries under its clutch. US will always try to never let any other country rise to same stature as itself.

    So Indians must forget, they can become superpower on the shoulders of US or China. 1962, showed how both are unreliable. So keep your own gun powder dry. Trade with US/Russia, for your own benefit and not for US/Russia benefit alone.

    http://www.tribuneindia.com/news/comment/an-unequal-agreement/223771.html
     
    Last edited: Apr 18, 2016
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