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Knifefish Mine-hunting UUV to Begin Operational Testing in 2015

“Knifefish provides capability that we don’t have with UUVs today,” said Capt. Duane Ashton, a program manager for unmanned maritime systems with the Program Executive Office Littoral Combat Ship (LCS).

The UUV’s enhanced mine-hunting capability will address the Navy‘s requirement to reliably detect and identify buried mines in high-clutter environments. It is a critical part of the littoral combat ship (LCS) mine warfare mission package.

The LCS mission package will include a pair of the UUVs in addition to launch and recovery equipment, a support container, spare parts and support equipment.

Knifefish is the new Surface Mine Countermeasure (SMCM) Unmanned Undersea Vehicle (UUV), built by General Dynamics Advanced Information Systems of Fairfax, Va., based upon a Bluefin-21 vehicle from Bluefin Robotics. The system was introduced April 16 at the Navy League’s Sea-Air-Space Exposition near Washington, D.C.

The LCS mission package will include a pair of the UUVs in addition to launch and recovery equipment, a support container, spare parts and support equipment.

Nadia Short, vice president for strategy and business development with General Dynamics Advanced Information Systems joined Ashton for the unveiling of the ¼-scale model Knifefish. General Dynamics Advanced Information Systems is the integrator.

Surface Mine Countermeasure Unmanned Undersea Vehicle (SMCM UUV)

The Surface Mine Countermeasure Unmanned Undersea Vehicle (SMCM UUV) developed by General Dynamics Advanced Information Systems will allow the U.S. Navy detect underwater mines. Photo courtesy of Edward H. Lundquist

At 19-feet-long, 21-inches in diameter, and a weight of 1,700 lbs., the minehunting system falls into the heavyweight category for UUVs. It is designed to use its low-frequency broadband synthetic aperture side-scanning sonar to look for mines that are in the water column, resting on or buried under the seafloor.  Those mines sitting on the bottom are called “proud” mines. What’s more, the UUV has a database and processor onboard that allows Knifefish to identify just about any kind of mine-like object it could encounter, including virtually all known types of sea mines.

Each reflection from an active transmission has unique characteristics that can be identified and classified. The details of how this works is classified.

“It knows what an anchor or a refrigerator looks like, and can rule them out” Ashton said. “And it knows with a high degree of certainly when it has found a mine-like object.”

The onboard database is huge, Ashton said. “There are terabytes and terabytes of data.”

The database is active and will be updated as required to support accuracy in the classification of bottom and buried objects.

The SMCM UUV started as a Science and Technology (S&T) program run by the Office of Naval Research. This S&T program transitioned to the SMCM UUV acquisition program and the information and data from the S&T program was used to help develop technology solutions for the acquisition program.

Ashton said ONR helped develop the two prototypes being used for testing while the Engineering Development Manufacturing (EDM) systems are being developed.

“We’ve taken it to sea and deployed it from a research ship,” Ashton said.

Ashton said after the EDM completion, EDM system testing will be followed by developmental testing, and finally operation testing. Knifefish is planned to be a part of the increment 4 LCS mine countermeasures mission package, which should be ready for operational testing in FY 2015. It could be operational by FY 2017.

The LCS mine warfare (MIW) mission package will contain two Knifefish systems. The concept of operations is to have LCS deploy the lithium-ion battery-powered Knifefish a safe distance from a minefield and have it conduct a preprogrammed search mission for up to 16 hours. The system will compare any objects it locates with its onboard database.

The vehicle periodically provides LCS with a GPS position and “wellness” update, using an onboard antenna and an Iridium satellite link, but must return to the ship and have its mission data that it has stored onboard extracted and analyzed. If during post mission analysis the LCS mine warfare mission specialists find that a mine has been located, classified and identified, they can then use the means available to dispose of the mine, such as the Airborne Mine Neutralization System or EOD divers. Or, they can mark the location of any mine hazards and inform friendly units to stay clear.

The system is designed for use with LCS, but it can also be used from vessels of opportunity. While the vehicle is the standard 21-inch diameter for submarine-launched torpedoes and UUVs, it is not designed to be deployed from a submarine.

Knifefish follows a preprogrammed path, but the operator can give it a new command and maneuver the vehicle to go to a new location, Ashton said.

The UUV is designed to be turned around quickly, said Ken Sault, General Dynamics Advanced Information Systems program manager for Knifefish. “The UUV will have a subsystem called the Removable Data Storage Module [RDSM] which will contain all of the data recorded by the mission. The RDSM will be taken from the UUV and downloaded to shipboard processors for post mission analysis.”

“While the UUV is executing the next mission, the previous mission batteries are recharged and the RDSM prepared for reuse. To support this requirement, both the RDSM and batteries can be swapped out with ready spares,” said Sault.

Short said the vehicle was built with open architecture, which ensures that Knifefish will continue to evolve to meet mission needs and pace technology. “You can take the vehicle, put the batteries you need inside and the sensors you need up front and adapt the system for the mission.”

According to Short, General Dynamics Advanced Information Systems is the prime contractor and systems engineering lead, responsible for payload and mission module integration. The vehicle is provided by Blue Robotics. Ultra Electronics Ocean Systems is providing the low frequency broadband (LFBB) synthetic aperture sonar processing, with design and system engineering support from the Applied Research Laboratory of Penn State University (APL/PSU).


Capt. Edward H. Lundquist, U.S. Navy (Ret.) is a senior-level communications professional with more than...