Chris Ingalls

KING-TV, Seattle

SEATTLE — A band of amateur scientists selected by the FBI to look for clues in the world’s most infamous skyjacking may have found new evidence in the 45-year-old case.

They’re asking for the public’s help because of potential leads that could link the hijacker known as D.B. Cooper to the Puget Sound aerospace industry in the early 1970s.

The scientific team has been analyzing particles removed from the clip-on tie left behind by Cooper after he hijacked a Northwest Orient passenger jet in November 1971.

A powerful electron microscope found more than 100,000 particles on old the JCPenny tie, including cerium, strontium sulfide and pure titanium.

“These are what they call rare earth elements. They’re used in very narrow fields, for very specific things,” said Tom Kaye, lead researcher for the group that calls itself Citizen Sleuths.

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Kaye said the elements were rarely used in 1971, during the time of Cooper’s daring leap with a parachute from the passenger jet.

One place they were being used was for Boeing’s high-tech supersonic transport plane, which was being developed with government funding in the 1960s and 1970s.

Kaye wonders if Cooper could have been a Boeing employee or a contractor who wore the tie to work.

“The tie went with him into these manufacturing environments, for sure, so he was not one of the people running these (manufacturing machines). He was either an engineer or a manager in one of the plants,” Kaye said.

Kaye says Boeing was developing cutting edge monitors, like radar screens, that used some of the elements found on the tie.

Kaye says the public’s help is needed, particularly from old-timers with experience in the aerospace industry in the Pacific Northwest.

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The scientists would like to hear theories from the public on what those materials could have been used for. They hope the information can help build a profile of Cooper.

“Someone may be able to look at those particles and say ‘Oh my gosh. I know what that means having those particles on the tie,” Kaye said.

Tipsters can reach the group through the “contact” tab on the Citizen Sleuth website.

On Thanksgiving Eve 1971, a man aboard a Portland to Seattle flight told the flight attendant he had a bomb in his suitcase. He demanded $200,000 and four parachutes, which the FBI delivered when the plane landed at Sea-Tac Airport in Seattle.

When the plane was airborne again, headed south, the man who became known as D.B. Cooper jumped from the back staircase of the Boeing 727 with a parachute on his back into the frigid night sky and vanished.

The FBI closed the case last year unsolved.