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Defending the Fleet in Harbor

Stevens Institute of Technology Studies Navy Antiterrorism and Force Protection Measures

By Steve Dunham

Journal of Homeland Security, April 2004. Copyright 2004 Analytic Services. Reproduced with permission.

How can the U.S. Navy protect its ships in harbor from attacks by small boats and swimmers? Stevens Institute of Technology, in Hoboken, NJ, is working on the answers.

Stevens has received a grant from the Office of Naval Research to study force protection for the fleet. The systems being studied would use sensors to create a picture of the area around moored ships, monitoring activity on the surface and underwater. It’s not just about surveillance in ports, however. It’s “more challenging than just ports,” said Michael Bruno, director of the Davidson Laboratory and professor of civil, environmental, and ocean engineering at Stevens. “It’s concerned with the maritime operating environment. It’s more like the Coast Guard’s concept of maritime domain awareness,” in contrast to the U.S. Customs and Border Protection Service’s Container Security Initiative.

“Although ports in general already address security issues, they do so in a hitherto uncoordinated way which inevitably leads to a less-than-best-use of resources and experience,” according to the European Commission on Port Security.

European Transport Commissioner Loyala de Palaci has pointed out that “ports go far beyond this relatively narrow strip of land; they are vulnerable in all their constituent parts.”

Dominik Donald of Aegis Defense Services believes that al-Qaeda “and its associates may be planning a maritime spectacular.”

The need to respond to the threat attracted the researchers at Stevens. The institute has been working for a long time in ocean and atmosphere observation, and it was Stevens that came up with a proposal for the Navy. The seeds of the present research came from work on safe navigation and on the environment. The present work involves micro observing systems, with high resolution of an area from a few miles offshore through the surf line to the shore—what are considered near-shore areas.

Guarding Against Small Boat Attacks

The surface surveillance system would be designed to monitor bodies of water such as estuaries, like New York harbor. It would track small vessels. Both the U.S.S. Cole (on 12 October 2000) and the French tanker Limburg (on 6 October 2002) were attacked by small vessels, Bruno pointed out.

The surface surveillance system would continuously monitor vessel traffic in New York harbor. It would be continuously on, tracking commercial craft, pleasure boats, ferries, etc. It would assimilate the data and create a mosaic of what is happening in the harbor at any one time. Analysis tools could interpret the mosaic. First the researchers at Stevens must develop the picture, then the methods to analyze it.

The research approach taken by Stevens starts with the approaches to the harbor. The port of New York and New Jersey is vulnerable to a vessel’s being sunk in the channel. This would be a relatively simple way to disrupt operations. To monitor the water farther out—to the continental shelf—Stevens is collaborating with Rutgers’ Institute for Marine and Coastal Sciences.

Stevens will be constructing a maritime security testbed and will invite others to use it. Bruno expects that the opportunity to work with the Navy and the Port Authority of New York and New Jersey and demonstrate systems for them will attract corporations that want to test sensory hardware and software in a demanding environment. He suggested that cameras, underwater acoustic instruments, and autonomous underwater vehicles might be tested. An autonomous underwater vehicle, he said, might randomly patrol the harbor and be directed by the control center to inspect areas of interest.

The data collected by the surveillance system will need to be transmitted to the analysis center, requiring secure communications. The Center for Wireless Network Security at Stevens will work on this.

The sensors themselves will need to be portable and mobile. In the demonstration, New York Waterway ferries will host the sensors. In other ports, sensors could be placed on what Bruno calls “vessels of opportunity”—ferries or other craft already in the harbor—rather than require new or dedicated vessels to conduct the monitoring.

Although the demonstration project is funded by the Navy, it will be designed for full port protection. Stevens is talking to the Coast Guard and meeting with the Port Authority, which says it will help in any way it can.

Most port security dollars at present are going to first-order security measures, such as fences, said Bruno. The system being developed by Stevens would be a second- or third-order system, but it ought to be ready to use when security measures get to that point.

Bruno sees the technology as 100% applicable to other areas. He expects spinoffs of the technology, perhaps to navigation and environmental monitoring, areas Stevens was involved with already.

Besides monitoring vessel traffic, the system would keep track of the weather. Thomas Herrington, research assistant professor in Stevens’ Civil, Environmental, and Ocean Engineering Department, has done work with the National Weather Service and the National Hurricane Center. He noted that weather can limit the surveillance capability of some systems, and he said that part of the surveillance system that Stevens is working on will monitor and forecast weather, such as winds and tides, so that in the event of a ship adrift or a spill, the authorities would immediately know where the ship or spill would head and when. Sensors and computer models would learn and would present a “forecast you can trust.”

Rapidly Deployable Antiterrorism–Force Protection Systems for Underwater Threats

U.S. Navy ports and ships are vulnerable to almost every category of underwater threat, yet urban waterways with commercial and recreational boat traffic are not conducive to physical barriers.

Recent events and activity underscore the emerging interest of al-Qaeda operatives in training scuba divers, so developing protective measures is an imperative.

Developing technology to deal with swimmers is a serious challenge. To defend ships against underwater swimmers requires a detailed understanding of the environment; factors such as water depth and current patterns impair the ability to deploy, operate, and maintain sensors and the ability to interpret sensor observations. High currents, high turbidity, and stratification present unique challenges to sensors, and the presence of debris, fish, etc., could trigger unacceptable levels of false positives.

However, Stevens says it has the expertise to meet the challenge. It has research vessels and acoustic, laser, and optical observing systems. It has towing and maneuvering tanks for testing models. It has ECOM—the estuarine and coastal circulation modeling framework—the most widely used ocean forecast model in the world, used by the Navy and by the National Oceanic and Atmospheric Administration and many other agencies. Stevens also has a field test bed on the Hudson River waterfront.

Field observations of the ocean and atmosphere are standard work at Stevens, measuring surface currents and waves, turbidity, salinity, water temperature, wind, air temperature, and air pressure and creating ocean and atmosphere computer forecasts, including multi-scale prediction of the impacts of chem-bio releases in the atmosphere. Finally, Stevens Institute of Technology has longstanding relationships with the Navy, the Coast Guard, the Port Authority, the National Oceanic and Atmospheric Administration, the Federal Emergency Management Agency, and industry representatives.

To detect, classify, and track underwater threats, Stevens proposes, first, a rapidly deployed system to create a small or well-defined exclusion zone. It would use commercial, off-the-shelf technology; it would be deployable from air or water; and it would be inexpensive. However, there are serious challenges to meet: ambient noise, stratification, secure wireless communication, signal processing and rapid display of information, threat assessment modeling, and decision making. Additional sensors would be able to detect a scuba tank or a swimmer delivery vehicle and thereby assist in target classification.

The second element in the Stevens proposal is an integrated, wide-area underwater surveillance and forecast system to create large exclusion zones or to secure navigation channels. This would use existing Stevens modeling technology and commercial, off-the-shelf autonomous underwater vehicle technology. This element faces some of the same challenges as the rapidly deployable system—secure wireless communication, signal processing and rapid display of information, threat assessment modeling, and decision making—plus control of the autonomous underwater vehicles.

Control of the vehicles can be improved. Model-based preliminary analysis allows for optimization of sensor type and vehicle routing, with ongoing refinement during operation. The forecast model will control the vehicle and increase efficiency by taking advantage of knowledge of ambient conditions, such as turbidity, currents, and water depth.

The primary challenge is the detection and classification of swimmers—measuring the wake and noise they generate, initially in the Davidson Laboratory’s high-speed towing tank, with the tests repeated in the estuary environment of the Hudson River. The next step will be computer modeling of the wake and noise generated by a swimmer. This will assist in predicting swimmer signature characteristics—both acoustic and non-acoustic—over a range of conditions and will provide guidance for selecting detection and tracking technologies. Then Stevens will assess the underwater acoustic conditions in an urban estuary.

Integrating the Protective Systems

Stevens plans to create intelligent systems that know the marine environment and can quickly distinguish the roving small boat from the ferry and can spot a swimmer with explosives who is moving among the fish and flotsam. The instrumentation must be combined with real-time data analysis, because once a threat is identified, there will be little time available to protect a moored ship. Stevens will be working on the aspects of logistics and assets management to ensure that the threats are identified and thwarted rapidly—to connect the dots, as it were, even when the dots are underwater.