New coating-based cloaking technology could make U.S. Navy subs and unmanned undersea vehicles even stealthier, developers say.
The underwater acoustic-evading technology creates a coating that features broadband, passive waveguides that redirect acoustic energy around an object, “rendering it nearly undetectable” to active sonar, Aviation Week Intelligence Network (AWIN) reports.
U. S. Navy
|The Virginia (SSN 774) is an advanced stealth nuclear-powered submarine for the post-Cold War era. Clad in acoustic-evading cloaking, it could be even stealthier, developers say.|
The project is in the second phase of development, supported by a $446,833 Navy Small Business Innovation Research (SBIR) grant awarded in FY 2010.
Phase II of the project, called “Metamaterials for Acoustic Cloaking,” is aimed at formulating, manufacturing and testing prototype cloaking materials that were designed in Phase I using computational simulation technology.
Acoustic metamaterials are artificially fabricated materials designed to control, direct and manipulate sound in the form of sonic, infrasonic, or ultrasonic waves, as they might occur in gases, liquids and solids.
The work is being performed by New York-based Weidlinger Associates Inc., a structural engineering firm that specializes in building and transportation design, applied science research, and physical security.
The technology involves “carving up and altering” aluminum to give it “elastic properties”—or what the company calls “metal water,” principal investigator Jeffrey Cipolla said June 4 in a presentation at the 2012 Navy Opportunity Forum outside Washington, D.C. The forum offered a preview of more than 250 Navy-supported technologies in development.
The coatings “decouple” structural vibrations from the water, reducing passive sonar signature, AWIN reported. The cloak “suppresses all scatters and reflected waves,” Cipolla said.
But don’t grab your paint brush yet. This is no spray-on coating, Cipolla told AWIN. “It’s going to be a structure that has to be attached to the sub.”
And that structure won’t weigh lightly—a significant consideration when evaluating the technology for Navy vessels.
Said Cipolla: “Any cloak technology worth its salt is going to be heavy.”