Every year, a team of scientists and researchers dive into the waters of the western Pacific republic of Palau, armed with underwater drones, thermal cameras, metal detectors -- and the drive to solve a decades-old mystery.  On Friday, GoPro released a short film documenting an expedition the action-camera company participated in with the BentProp project, a group dedicated to recovering World War II planes shot down in the western Pacific.

The extraordinary project taps into some very high tech. But it all started, quite literally, with a wing and a prayer.

In 1993, Pat Scannon found the 65-foot wing of a B-24 bomber while on an expedition in Palau. The find, and the realization that he could solve decades-old mysteries for the families of the crew who went down on that plane, struck a deep chord with Scannon. He's  been working ever since to recover as many planes as he can from the sea bed of the reef of off Palau.

"I was very much affected by that," Scannon said. "No one knew anything about what had happened to that plane or its crew, and I decided it needed to be answered."

For years, Scannon searched for planes on his own or with a small team of researchers, based on military records of planes that had gone down, as well as dozens of eyewitness accounts from interviews he conducted with Palau natives, some of whom were children when they saw the planes go down into the ocean.

In BentProp's early days, Scannon said, he and the team he built relied mostly on legwork and their own dives, often in milky water that made it very difficult to search. As technology evolved, the task got easier: Scannon said, for example, that Google Earth did wonders for being able to plot out his expeditions.

Then, three years ago, Scannon was introduced by chance to a team from the Scripps Institution of Oceanography, based at the University of California, San Diego, and a team from the University of Delaware. The oceanography teams were working on ways to explore and map the ocean floor in Palau. The two groups quickly struck a deal to work together.

It's hard to overstate the impact that the technology -- even the simple addition of drones equipped with cameras donated by GoPro -- has had on the searches. The waters BentProp is searching are relatively shallow -- 100 to 300 feet deep, Scannon said -- but can pose dangerous risks to divers who stay on the sea floor too long. Using underwater drones with cameras lets the searchers look for debris all day, rather than in short bursts. Being able to scan for a plane's debris field lets them use their dive time more efficiently.

In the dive documented in Friday's video, the teams used the technology to find the wreckage of an Avenger torpedo bomber that it first found evidence of in 2005.  "After searching over a nine-year period [for one plane], with the technology from Scripps and the University of Delaware, we found it in one day."

Finding a plane is an almost indescribable experience, Scannon said. The video GoPro released showed Scannon and  Eric Terrill, who leads the Scripps team, sharing a handshake over the propeller -- a restrained gesture, but the only one that they could muster in the moment. "You really can’t hug underwater -- you get tangled up," Scannon said. "But it was a very emotional handshake because we knew that, in all likelihood, there were Americans missing right below us."

With the Avenger debris, as with all of the group's finds, the organization holds its own simple flag-folding ceremony in the water over the plane; a retired Navy lieutenant commander receives the flags on behalf of the families, who don't learn of the finds until they've been verified by the U.S. government.

Based on estimates derived from his research, Scannon believes Bent Prop could still find 70 to 80 more MIAs in the waters around Palau. The U.S. Office of Naval Research has since sponsored a pilot program to help the university teams find soldiers missing in action, and to use these expeditions to encourage young people to get interested in the science behind it.

"As scientists, we're not typically out in the public telling our stories," Terrill said. "This particular project has motivated us. We can send messages back to the families and show there's still a lot of U.S. interest in thanking them for their service."

"I initially thought this would be a one-plane adventure," Scannon said, but now he's driven to keep going because of the families of these soldiers. The U.S. government, through the Joint POW/MIA Accounting Command (JPAC), verifies and informs relatives of BentProp's findings. But on occasion the government allows Scannon to deliver the folded flags to the families himself.

What strikes him speechless every time, he said, is the fact that even though these soldiers have been gone for generations, they still often hold a place of honor in their families' homes -- even among family members who never even knew their fallen relatives.

"MIA families never forget," he said. "They never, ever forget."