PORTLAND, Ore. -- "First thing we are going to do is dip it in the water and get it a little bit wet," Tom Kaye showed us how he tests the flow of money in the Columbia River.
Kaye is a paleontologist as well as an associate researcher at an institute in Seattle. He and his team are on a weeklong field trip trying to solve the nation's only unsolved skyjacking, the DB Cooper case.
For Kaye, it's all about the money because the "Cooper Cash" found after the skyjacking is the only physical evidence that exists after Cooper parachuted out of the commandeered plane.
Back in 1971, Cooper hijacked a plane from Portland to Seattle. He demanded $200,000 and parachutes. After his demands were met, he jumped into the dark Northwest sky and vanished.
Nine years later, Brian Ingram found some of the ransom money. He came across the buried bundles of cash on a stretch of beach called Tena Bar not far from Vancouver.
"It was a lot larger than we thought it was," recalled Ingram.
Ingram is helping Kaye on his quest.
Kaye is testing the theory the cash floated down the Washougal River near Cooper's drop site where it later floated into the Columbia. Kaye says his research is already yielding some answers.
"This is why we do these experiments. If you had asked me what happens to money, I would've thought it floated," said Kaye.
He will compare his findings to three of the remaining seven bills lent to him by the FBI.
The bureau no longer considers the Cooper case a priority. It opened the investigation to the public. Six months ago, Kaye stepped up to see if he can solve it.
But not everyone wants it solved. Ingram likes that after 38 years, the Cooper case is still a mystery.
"I like the idea that no one knows, that everyone keeps asking about it" he said.