I think that this technology is probably oversold, otherwise we would not see it in Aviation Week.

If it worked, it would be so classified, we wouldn’t even hear rumors of it.

New Sensor Detects Submarines(Subscription Required)
New Sensor Detects Submarines
Aviation Week & Space Technology
07/02/2007, page 13

Edited by Edward H. Phillips

Printed headline: Hide and Seek

Scientists at the Georgia Institute of Technology have developed a sensor that measures the motion generated by sound waves under water. A series of the device could be configured in compact arrays and deployed by the U.S. Navy to detect enemy submarines. According to Francois Guillot, a research engineer at the George W. Woodruff School of Mechanical Engineering in Atlanta, the sensor is capable of detecting small sounds despite the surrounding noise of the ocean, and it provides clear directional information. In addition, the sensor can be modified to measure water deformation, or shear, associated with a sound wave. The research is being supported by a grant from the Office of Naval Research.

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