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Home : Media : News
NEWS | April 27, 2022

Through the Lens of a Carderock Detachment: Welcome to SEAFAC

By Edvin Hernandez, NSWC Carderock Division Public Affairs

Located on the northern tip of the West Coast, more than 4,000 miles away from its headquarters in West Bethesda, Maryland, is Naval Surface Warfare Center, Carderock Division’s Southeast Alaska Acoustic Measurement Facility (SEAFAC). Operating in a remote environment, SEAFAC is the Navy's primary acoustic engineering measurement facility in the Pacific.

The waters in Behm Canal near Ketchikan, Alaska, are an ideal location to conduct acoustic trials, according to SEAFAC Site Director Jennifer Kelso.

“We have an important, dedicated mission to support The Pacific Submarine Force,” she said. “SEAFAC is an ideal location for recording acoustic measurements because we are located in a glacial fiord that is protected by Prince of Wales Island from open ocean shipping noise. It makes for a pristine acoustic environment.”

Although submarines have the capability to submerge and avoid being seen by their adversaries, their signature level is just as important to evade detection.

“There are a number of reasons why you might care about your acoustic signature,” Kelso said. “The noise you’re putting into the water can make you identifiable. Although all Navy vessels care about the noise they are putting into the water, our submarines have a focused stealth interest in understanding their acoustic signature.”

SEAFAC provides the capability to perform research, development, test and evaluation to determine the sources of radiated acoustic noise, to assess vulnerabilities and to develop quieting measures for military ships. In many instances, real-time analysis of the signature allows analysts to identify and provide corrective recommendations before the vessel leaves the facility. By using dual bottom-mounted acoustic arrays, Carderock personnel can record the signature of a submerged submarine in transit for different speeds and operating conditions. They can test motionless submarines, too, at their permanently moored static measurement site.

Suspension barges with mooring cables are used to hold submarines in position at the testing depth between the measurement arrays. Once in position, the analysts evaluate acoustic signatures of individual ship components and systems. Carderock engineers and scientists provide real-time data analysis to the crew aboard, and adjust as needed.

Submarines, however, are not the only vessels that can be evaluated at SEAFAC. The facility has measured Navy surface ships and even cruise ships, in the past. Because the functions and capabilities of this facility are valuable to the Navy, Kelso and Deputy Site Director Eric Simon have their hands full with coordinating site testing logistics and keeping the public informed of Navy activity in the shared water space of Western Behm Canal.

Kelso, who has been the SEAFAC Site Director for the past six years, said she is required to notify the public when any restrictions will be placed on others vessels operating in the canal. This notice, and radio communication, advises other boats in the area how to safely operate in the canal around SEAFAC operations and in a way that minimizes interference with data collection.

“When a test vessel arrives here, we have to deal with the weather that we have and any surface contacts, including other users in the same water space such as small boats in the area,” Kelso said. “Those things will all increase the ambient noise level in the water and effect what we can actually measure.”

The Environmental Protection Agency requires federal agencies to conduct thorough planning for any actions that may have an effect on the environment. Simon and Kelso said they have to go through a formal process to show prudent environmental planning before installing new instrumentation in the water or on their shore-side facility on Back Island. This includes any changes to their buildings or infrastructure footprint. The weather, on the other hand, is another factor Kelso and Simon have to plan around.

“Weather can also have a significant effect on our operations from a safety perspective,” Kelso said. “Not only do we need a quiet environment, but we need the water conditions to be safe enough to transfer our people on and off the small boats and decks of the submarine. The wind, amount of rain and wave action can make that difficult.”

Precipitation is another uncontrollable variable that influences the acoustic data collected. According to Simon, snow is louder than rain and when the thermal layers in the water change, it affects the way sound travels.

“We’ll go into our trials with a plan, but it always changes after the first day,” she said.

At SEAFAC, Kelso’s team works around the clock to complete the mission.

“We test year-round,” she said. “In the winter, we might get higher ambient levels because of weather, but we have far fewer people in the water who we are sharing that space with. Summertime is the opposite. Ambient levels are lower, but we have more contact interference. That’s one reason why during trials we are testing for 24-hours, because sometimes our best window will be overnight.”

On a day-to-day basis, she and Simon are working to proactively communicate with visitors in the area and educate the public about SEAFAC. The Navy has been conducting acoustic trials in Ketchikan for more than 30 years, and Kelso continues to ensure the mission is executed smoothly. When a trial is underway, Carderock sends their best from their detachments and headquarters to support.

Carderock’s Commanding Officer Capt. Todd Hutchison recently visited SEAFAC, touring the facility’s buildings and static site in the Behm Canal. Hutchison thanked Kelso and Simon for their leadership and returned to West Bethesda, eager for his next visit.