Underwater Awareness

Underwater Awareness

Nuanced Approach Needed to Build Acoustic Capability

Cmdr. (Ret.) Dr. Arnab Das/Indian Navy

The rise of India and the People’s Republic of China (PRC) as economic and political powers places more strategic significance on the tropical littoral waters of the Indian Ocean and the South China Sea. These waters have a unique bearing on naval deployments and, more importantly, on underwater system deployments. As threats from beneath the waves continue to rise, security partners in the Indo-Pacific need to take a fresh look at how they achieve underwater domain awareness (UDA). Militaries that compete with nonmilitary stakeholders for funds must bring diverse communities together to achieve common goals.  

The maritime domain awareness (MDA) concept achieved substantial prominence after the 9/11 terrorist attacks. The global community got together to build infrastructure and capabilities to address MDA limitations, and security forces teamed up with the research community to enhance their MDA capabilities. In the Indian Ocean region, following a series of terrorist attacks in Mumbai in November 2008, India’s government started working to ensure respectable levels of MDA. The Indian Navy embarked on an ambitious plan to develop infrastructure and capabilities.

MDA in its present form needs to be understood before we attempt to connect UDA to it or to define UDA from a new perspective. The MDA framework declared by the U.S. Department of Homeland Security in October 2005 in its “National Plan to Achieve Maritime Domain Awareness for the National Strategy for Maritime Security” doesn’t mention the underwater threat or a mitigation strategy. The U.S. did not consider the underwater threat to be substantial at the time. After 9/11, the U.S. recognized the possibility of other avenues that terrorists might use to harm U.S. interests, but the underwater threat did not explicitly figure into strategic formulations.

The U.S. Navy now funds research on the effects of sonar testing on marine life after NATO sonar tests were believed to have contributed to the stranding of Cuvier’s beaked whales in 1996. OURBREATHINGPLANET.COM

U.S. Navy Lt. Cmdr. Steven C. Boraz in a 2009 report brought out the myths and realities of the era and recognized the limitations of a Navy-driven MDA. As late as February 2015, the academic literature recognized the limitations of U.S. capabilities in dealing with underwater threats. The U.S. Coast Guard, which is the primary agency responsible for MDA through the ports, waterways and coastal security mission, has made significant investments in surface and air assets as well as in increased command-and-control capabilities. Little has been done, however, to expand the mission to the underwater domain. 

The underwater threat from nation-states, terrorists and criminal organizations is on the rise, and multiple outfits are acquiring capabilities that can outwit risk mitigation strategies of security establishments. Nations such as North Korea, the PRC and Russia have submersible capabilities that can be deployed to inflict large-scale damage on maritime assets. Nonstate actors such as the Moro Islamic Liberation Front, Revolutionary Armed Forces of Colombia and the Liberation Tigers of Tamil Eelam have deployed submersibles to attack their adversaries.

Sensor Challenges

The underwater wireless sensor networks that may be deployed for multiple underwater surveillance applications face unique challenges in harsh underwater-channel environments with low bandwidth, high propagation delays and higher bit error rates. The variable speed of sound and the significant node mobility due to water currents pose another set of unique challenges. These underwater-channel distortions and site-specific challenges require focused mitigation strategies that limit their deployment for broader UDA applications.

Underwater technology development, and more specifically acoustic technology development, matured during the Cold War when the U.S. and then-Soviet Union invested heavily in the deep waters and achieved significant success in stabilizing sonar performance. Massive field experiments at sea validated the algorithms and minimized medium uncertainties. When the naval focus shifted to the littoral waters after the Cold War, the principles that stabilized sonar performance in the deep waters did not apply, resulting in suboptimal performance. Shallow-water acoustics have their own challenges, and the experimental work required is far beyond the means of developing countries, making it an exclusive club.

The Cold War saw unquestioned military investments and technology development for national security. When the Cold War ended, however, the national security apparatus did not receive the same level of support, resulting in multiple projects getting stalled. The sound surveillance system was a large underwater sensor network project driven by the U.S. Navy beginning in 1949 to monitor Soviet vessels in the GIUK gap. The GIUK gap, an area in the North Atlantic Ocean that forms a naval chokepoint, is an acronym for Greenland, Iceland and the United Kingdom. Toward the end of the Cold War, shore stations for the surveillance system had to be opened for academic research to support their operational and maintenance cost. The project significantly boosted the underwater acoustic field research that stabilized sonar performance in the deep waters for multiple nonmilitary applications.

An autonomous underwater vehicle is used to search for Malaysia Airlines Flight 370. AFP/GETTY IMAGES

The Point Sur naval experimental facility in California opened in 1958 and had to be shut down in 1984 for lack of funds. A ship shock-test facility and the Surveillance Towed Array Sensor System Low Frequency Active project, known as SURTASS-LFA, had to be relocated and scaled down due to opposition from the nonprofit Natural Resources Defense Council on environmental grounds. The council compelled the Navy to file an environmental impact statement for the first time in the early 1990s. In 1996, 13 Cuvier’s beaked whales, a deep-diving breed that rarely strand, were found stranded off the coast of Greece. Dr. Alexandros Frantzis, a biologist at the University of Athens, linked the stranding to the use of sonar in the immediate area. NATO was involved in a joint international experiment using a high-powered, low-frequency sonar at the time of the stranding. The event became a massive rallying point for environmental activists, and they demanded a ban on such trials. The U.S. Navy was forced to fund research on the impact of such trials on marine animals. These incidents reflected a geopolitical shift in which socioeconomic issues had to be balanced with national security demands.

MDA has remained an event-driven construct. The 9/11 attacks in the U.S. triggered massive efforts toward MDA, and the Indian government took major steps toward MDA after the Mumbai attacks. Both initiatives have remained security-driven and have not received much support from other stakeholders. Security officials, citing classified data that could harm national security, have kept information firmly in their grip. A key challenge in a developing nation such as India and many other nations in the Indo-Pacific is that allocating massive funds for security requirements is politically unviable, given other priorities. Thus, MDA has remained limited due to lack of resources and an absence of a whole-of-nation approach. UDA as a security-driven construct, therefore, will be extremely hard to fund because of its resource-intensive nature, which makes it politically harder to support.

A more nuanced approach is required, given the challenges of increasing underwater threats and the underwater risk mitigation strategy becoming an exclusive club of countries with high-tech capabilities. UDA should take on a far different structure rather than being treated as a mere extension of the MDA and an exclusive security construct.

Acoustic Capacity and Capability Building

The post-Cold War period saw two major UDA developments. The first is the shift in underwater security activities toward littoral waters. The second is effective acoustic capacity and capability building. The early 21st century is seeing a significant revival of acoustic capacity and capability building to overcome the tropical littoral challenges. Three major components deserve attention:

To See – networks of sensors provide awareness.

To Understand – acoustic analysis and interpretation.

To Share – a network transmits actionable information in real time.

Traditionally, a small group of nations have made sensors and controlled their availability. While indigenous production of underwater sensors is desirable, Indo-Pacific nations can still manage with imported sensors.

Significant progress has been made in the development of networking technologies. However, the acoustic analysis in the littorals of the Indian Ocean region requires customized efforts to overcome site-specific medium distortions. This would involve massive shallow-water acoustic measurement (SWAM) experiments to collect acoustic data followed by signal-processing efforts to model the underwater channel and ambient noise.

SWAM experiments require two main inputs — platforms to access the nooks and crannies in the undersea domain and signal-processing abilities to derive meaningful inputs. The conventional shipborne deployment of sensors has not yielded desired results and is expensive to cover the massive area that needs to be studied. Underwater gliders have proven to be the best-suited platform for undertaking underwater acoustic surveys. The buoyancy engine-driven gliders are slow, cheaper and have long endurance and are less noisy. They can be deployed in large numbers to cover huge areas and then stitched together for data analysis. They are among the recent advancements in autonomous underwater vehicles, but since they are not propeller-driven, they can be used for acoustic data collection because they produce little noise and have long endurance.

Acoustic analysis capabilities have remained limited to a small group of countries, including Australia, France, Japan, the U.S. and members of the Nordic Acoustic Association. Littoral anti-submarine warfare has been a recent phenomenon, and some Indo-Pacific countries have invested in these capabilities. The U.S. began to be concerned about Chinese belligerence in the maritime domain, particularly in the South China Sea, toward the end of the 20th century. The Asian Seas International Acoustics Experiment (ASIAEX) was a massive SWAM project that started at the beginning of this century. Initially, six U.S. universities led by the University of Washington planned the first phase of the project. In phase two, 20 universities from China, Taiwan and others were included. 

The construct had far-reaching geopolitical overtones. The U.S. needed data to overcome the tropical littoral challenges in the South China Sea, so the entire experiment was funded by the Office of Naval Research but led by academia. ASIAEX was only the beginning, and the U.S. government routinely undertook acoustic data collection by streaming acoustic arrays and deploying underwater drones in the South China Sea. The Chinese realized and accepted their limitation of undertaking such large-scale SWAM experiments, so they participated with the U.S. to learn. They followed it up with a massive drive culminating in the Underwater Great Wall project. In December 2016, the PRC seized a U.S. underwater drone deployed from the USNS Bowditch. The incident was an official declaration by the Chinese that they were interested in moving forward with their own acoustic development program. 

When Malaysia Airlines Flight 370 disappeared during a flight from Kuala Lumpur, Malaysia, to Beijing, China, in March 2014, the PRC was keen to lead the search operation. More than 90% of the passengers were from China. Indo-Pacific partners assigned the role to Australia, restricting PRC involvement in the massive development of acoustic capacity and capability that occurred during the three-year search. 

Acoustic capacity and capability development in the tropical littorals can only happen with massive SWAM experiments. These are extremely resource-intensive and need to be funded at a different scale and supported with cutting-edge technology. Indo-Pacific partners need to pool resources and coordinate efforts to make this a success.

The UDA framework is a proposal that will bring transparency. Typically, there are four broad stakeholders of UDA that have attempted to generate understanding of the undersea domain to further their interests. 

National Security Apparatus: The inaccessibility and opaqueness of the underwater domain present a complex problem for surveillance and identification of disruptive elements. The involvement of nonstate actors further complicates matters. This keenness for undersea awareness from the security perspective means defending sea lines of communication, coastal waters and varied maritime assets against the proliferation of submarines and mine capabilities intended to limit the access to the seas and littoral waters. 

Blue Economic Entities: Trade and connectivity to the world help ensure energy and food security. The oceans are a vast reserve of resources that can contribute to the economic well-being of a nation. Massive opportunities in sectors including pharmaceuticals, oil and gas, undersea mining, logistics and shipping are waiting to be seized. 

Environmental Regulators and Disaster Management Authorities: The oceans are also a place where multiple natural disasters originate. It may not be possible to prevent a natural disaster, but early warning can minimize the loss of life and property. Human activities in the maritime domain are causing environmental degradation and are a threat to sustainable growth. Regulatory authorities and management entities need to gear up to meet the challenges of the future.

Science and Technology Providers: There is always a requirement for safe, secure and sustainable growth in the underwater domain. Science and technology will always be the main driver for such endeavors. Understanding the undersea ecosystem, the interaction among the multiple components of the ecosystem and the impact of human interventions on the ecosystem will require more research. 

The conventional approach of stakeholders pursuing their own UDA efforts has serious limitations, given the competition for resources to fund them over a long period of time. This has limited UDA efforts to an exclusive club of nations. It is now time to build a universal system that can minimize conflict and bring peace and harmony internationally.

Figure 1 presents a comprehensive perspective of the UDA framework. The underlying requirement for all stakeholders is to know the developments in the undersea domain, make sense out of these developments and then respond effectively and efficiently. 

UDA on a comprehensive scale needs to be understood in its horizontal and vertical constructs. The horizontal construct would be the resource availability in terms of technology, infrastructure, capability and capacity. The stakeholders represented by the four faces of the cube will have specific requirements, although the core will remain acoustic capacity and capability building. The vertical construct is the hierarchy of establishing a comprehensive UDA. The first level would be the sensing of the undersea domain for threats, resources and activities. The second level would be making sense of the data generated to plan security strategies, conservation plans and resource utilization plans. The next level would be to formulate regulatory framework and the monitoring mechanism at the local, national and global levels.  

The figure gives a comprehensive way forward for the stakeholders to engage and interact. The individual cubes represent specific aspects that need to be addressed. The user-academia-industry partnership can be seamlessly formulated based on the user requirement, academic inputs and the industry interface represented by the specific cube. It will enable a more focused approach and well-defined interactive framework. Given the appropriate impetus, the UDA framework can address multiple challenges faced by developing nations. The proposed UDA framework encourages pooling resources and coordinating efforts by all stakeholders to promote safe, secure and sustainable growth for all.

In the Indian Ocean region, UDA has a major role to play to prevent maritime confrontation. The addition of nonstate actors further complicates matters with the asymmetric advantage always with the subversive elements. The site-specific physical challenges demand special efforts to overcome them. Acoustic capacity and capability building deserve immediate and massive attention. Economic and political constraints in the region prohibit massive military investments. Thus, pooling resources and synergizing efforts is the only way forward.

Developing nations have their own challenges — resource limitations, technology challenges, governance issues and more. A systematic and comprehensive strategic approach will go a long way. The UDA framework as proposed is not a mere underwater extension of the MDA concept, but comprehensively addresses the safe, secure and sustainable growth model critically required in the Indo-Pacific strategic space.