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Games Navies Play: Anti-Access and Area Denial in Maritime Asia
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Cdr Abhijit Singh | Date:02 Jul , 2016 0 Comments
Cdr Abhijit Singh
Commissioned in the Executive Branch of the Indian Navy in July 1994, he is a specialist in Gunnery and Weapons Systems and has served on-board frontline ships.

On June 14, as Indian, Japanese and American warships began the fifth day of the 20th iteration of the Malabar Naval Exercises in the seas off Okinawa, they were informed of the presence of an unwelcome intruder.1

After returning from an exercise, the pilot of an F-18 fighter-jet informed the captain of the US aircraft carrier, John C Stennis, that he sighted a Chinese observation ship about ten miles away. As shockwaves rippled through the formation, the Stennis took avoiding action, opening out to 10 miles of the exercising ships and acting as a lone decoy. Meanwhile, in anticipation of a political backlash, Beijing announced that its ships were merely patrolling the Diaoyu islands (the Senkakus), which it considered to be Chinese territory.

Risky as it may have been, China’s deployment of a surveillance ship should not have come as a surprise at all. Beijing had issued a warning a few days earlier that it considered foreign naval drills in its back-yard a clear intrusion of its sovereign space. And on June 9, China dispatched three warships to a contiguous zone just outside Japanese territorial waters around the islands, seemingly to warn Tokyo that it would not concede its territorial claims to the Senkaku islands.2

What is surprising, however, is China’s brazen disregard for Japan’s red-lines with respect to naval ship movements near the Senkakus, which Tokyo administratively controls. While remodelled People’s Liberation Army-Navy (PLAN) warships, converted for use by the Chinese Coast Guard, have been known to operate near the territorial waters of the islands, there had so far been no instance of Chinese warships entering these waters.

Chinese analysts say that Beijing has been driven to resort to extreme measures owing to some provocative moves by the Japanese themselves. Tokyo’s announcement in March that it was expanding its East China Sea surveillance network around the disputed Senkaku Islands through the installation of a new radar observation station in Yonaguni Island near Okinawa was perceived by many in Beijing as an anti-access / area denial (A2/AD) measure to prevent PLAN ships from entering the East China Sea. Indeed, the addition of the large Izumo “helicopter carriers”, new Aegis destroyers with ISR capabilities, P-1 maritime patrol aircraft, upgraded SH-60K submarine-hunting helicopters and new Soryu submarines in the Japanese Maritime Self Defense Force (JMSDF) has created some unease in Beijing, which views these measures as aimed at countering the Chinese naval presence in the East China Sea.

Nothing, however, worries Beijing more than the US-Japan submarine surveillance effort in the Pacific. Since the early 2000s, when PLAN submarine patrols are supposed to have turned aggressive, the US Navy and JMSDF have installed a chain of fixed sensor arrays to monitor the movement of Chinese submarines. The upgraded system, dubbed the “Fish Hook Undersea Defense Line,” stretches from Japan to Southeast Asia with key nodes at Okinawa, Guam, and Taiwan. Its two separate networks of hydrophones, one stretching from Okinawa to southern Kyushu, and the other from Okinawa to Taiwan, have led Chinese analysts to claim the existence of a Japanese-American strategy to prevent Chinese submarines from operating in the far-eastern Pacific.

Meanwhile, India is said to be considering its own chain of undersea sensors in the Bay of Bengal. A recent report in the Indian media suggests that New Delhi is planning to undertake joint projects with Japan and the United States for the defence of its littoral spaces, including one involving the installation of a sound surveillance sensors (SOSUS) chain in India’s near seas. Japan is likely to assist India in the construction of an undersea network of seabed-based sensors stretching from the tip of Sumatra right up to Indira Point in the Bay of Bengal. Media reports suggest that Tokyo will finance the laying of an undersea optical fibre cable from Chennai to Port Blair. Once completed, this network is likely to be integrated with the existing US-Japan “Fish Hook” SOSUS network meant to monitor PLAN submarine activity in the South China Sea and the Indian Ocean Rim.3

While details are still scanty, it is possible that India’s actions in the Bay of Bengal were triggered by China’s anti-access/area denial (A2/AD) plans in Southeast Asia. Beijing’s near-coastal defence assets are a source of awe in Asia – in particular its rapidly growing submarine fleet, the anti-ship ballistic missile (DF 21D), anti-ship cruise missiles, and the Type 052D destroyers with enhanced air defence capabilities. But anti-submarine surveillance is still seen as its most potent passive weapon. In an article in April, Lyle Goldstein, a well-known China specialist, claimed that Beijing was in the process of creating an undersea “Great Wall” in the South China Sea by establishing an array of ocean-floor acoustic sensors to detect US submarines. China’s hydrophone system is reportedly modelled on the US Navy’s SOSUS, meant originally to track Soviet submarines in the mid-1950s. Reports that the PLAN is on the verge of operationalizing its sensor chain may have prompted New Delhi to pursue an undersea sensor project in the South Asian littoral.

Indian observers aver that Japan’s experience with working the system for over six decades has provided Japanese engineers and technicians with the proficiency and professionalism necessary to install sea-based sensors in distant littoral spaces, including in the Indian Ocean. Even so, New Delhi will need to consider the implications of operating sensitive equipment with a foreign partner – especially the sharing of critical sensor data. If the Japan-US SOSUS is an instructive example, then Indian policymakers are likely to be concerned. For, even though the JMSDF Oceanographic Observation Centre in Okinawa is jointly manned by Japanese and US naval personnel, all the information is available to the US Pacific Command, as the facility is under the operational control of the US Navy. Needless to add, there are concerns that India may be required to provide its foreign collaborators with a level of informational access with which the Indian Navy may not be too comfortable with.

Then there are concerns that placing undersea sensors around the Andaman and Nicobar islands might end up upsetting Beijing. Just as China is opposed to Japan’s activation of the surveillance unit on Yonaguni Island – fearing that the far-eastern islands might soon be upgraded to bear mobile anti-ship missile batteries and air-defence systems – it might resist the installation of Indian sensors, ostensibly citing their proximity to international shipping routes running alongside the Andaman and Nicobar, but believing that the islands could later be used for the deployment of offensive A2/AD assets.

Inadequate returns on investment constitutes another source of worry. Experts aver that the setting up of a listening array goes well beyond the placement of hydrophones on the seabed. A sound surveillance system requires steady economic and human investment, with the careful cultivation of an entire cadre of specialists able to interpret the array’s data output. The United States and Japan invested in their system for years before it began producing results. India could seek Japanese assistance in installing a SOSUS, but training specialists and refining the related technologies could take years.

Moreover, undersea sensors produce enormous quantities of raw data that require a dedicated system to sift and sort through. Over the years, the task of organizing the data collected has become increasingly unviable. The lack of resources to manage data-collection facilities has led to a proposal to market the data by sharing it with environmental scientists and civilian agencies for a price. In order to allow the access of data in real-time, however, the hydrophones have to be connected online, thereby raising concerns about the possible misuse of data.

Still, many Indian analysts believe that an Indian sound sensor array in the Indian Ocean could prove invaluable. For a country that has a major anti-submarine warfare handicap and a lack of operational submarines, an undersea sensor would be a godsend. India has so far not made any major investments in improving its submarine detection capabilities. If it can install a deterrence system and operate it with a degree of competence, it could retain its strategic primacy in the Indian Ocean.


1.“Chinese spy ship shadows US, Japanese, Indian naval drill in the Western Pacific,” The Times of India, June 15, 2016, at
2.“China sending remodeled Navy warships near Senkaku Islands,” Asahi Shimbun, June 13, 2016, at
3.Prasun Sengupta, “Undersea Web: A slew of projects to enhance India’s maritime security,” FORCE Magazine, April 2016, at


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