About 500 miles from the Philippines, Project Recover searches for aircraft shot down during one of World War II’s fiercest battles in the region.

The organization behind the project, BentProp Project, is focused on finding the remains of U.S. soldiers and bringing them back to the United States. This summer, the project received assistance from Remus, an autonomous underwater vehicle (AUV) equipped with side-scan sonar and advanced imaging systems. All these features help the AUV create a two-dimensional map that the project's team uses.

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Such technology is beyond the scope of what BentProp can afford. The vehicles come from the University of California, San Diego’s Scripps Institution of Oceanography and the University of Delaware, which received a grant from the U.S. Office of Naval Research. Scripps and the University of Delaware also sent underwater vehicles, cameras, various types of sonar, and, for aerial surveys, an autonomous hexacopter drone that had been rebuilt to survive sea spray and aquatic landings.

Pat Scannon, founder of Bent Prop, told PopSci the technology was revolutionary. “On land our major technology was a machete, and underwater it was scuba tanks,” he says. “The ability to extend our mission is, like, I don’t know how to describe it. It’s like starting out walking, and suddenly you’re in a supersonic jet.”

Watch the video above for more on the project.

Image: Scripps Institution of Oceanography