PORTLAND, Ore. (KOIN) — The mysterious case of DB Cooper continues to hold sway in the collective imagination — and also in the work of crime historian Eric Ulis.

On Friday, Ulis began a 2-day dig looking for the skyjacker’s parachutes and a briefcase at Tena Bar along the Columbia River. That’s where in 1980 a boy found $6000 of the $200,000 ransom Cooper got before he jumped out of a plane, never to be seen again.

The dig will cover an area of significant interest that is about 300 square feet. Ulis, who starred in the “History’s Greatest Mysteries” episode “The Final Hunt for DB Cooper,” claims he identified this area the FBI never searched.

The dig will be streamed live on a DB Cooper Facebook page beginning at 10am Saturday.

Ulis said his theory is that Cooper buried the parachutes, an attache case and the money at the same time, but dug smaller holes instead of one much bigger hole. The area that Ulis and 4 volunteers will search is about 20-50 feet away from where the $6000 was found.

db cooper sketches 1971 ap_1526597543459.jpg.jpg

The facts of the case

On November 24, 1971, the night before Thanksgiving, a man described as being in his mid-40s with dark sunglasses and an olive complexion boarded a flight from Portland, Oregon, to Seattle-Tacoma International Airport. He bought his $20 ticket under the name “Dan Cooper,” but an early wire-service report misidentified him as “D.B. Cooper,” and the name stuck.

DB Cooper search_326361
A search for DB Cooper along the Columbia River around 1980 (File)

Sitting in the rear of the plane, he handed a note to a flight attendant after takeoff. “Miss, I have a bomb and would like you to sit by me,” it said.

The man demanded $200,000 in cash plus four parachutes. He received them at Sea-Tac, where he released the 36 passengers and two of the flight attendants. The plane took off again at his direction, heading slowly to Reno, Nevada, at the low height of 10,000 feet. Somewhere, apparently over southwestern Washington, Cooper lowered the aircraft’s rear stairs and jumped.

Despite an extensive search, there was no trace of Cooper until part of the money was recovered 9 years after the skyjacking.

In July 2016, the FBI announced they were no longer investigating the DB Cooper skyjacking case.