Chanté and Rick had kept quiet out of respect for their mother, Karen, who they believed may have been complicit in both crimes. But because both parents are now deceased, the opportunity arose for the siblings to voice their suspicions. And, crucially, they appear to have hard evidence: a modified parachute that they (and amateur DB Cooper sleuth Dan Gryder) believe was used in the daring escape.

“That scum is literally one in a billion,” Gryder said Cowboy stands daily after releasing a series on YouTube about his suspicions. It was that YouTube series, Gryder said, that drew the FBI back into the case.

According to Gryder, the FBI now has the parachute and harness that were once stashed in a storage shed on family property in North Carolina, along with a harness and a skydiving log that Chanté says shows DB Cooper’s movements near Oregon and Utah (the locations of the two skyjacking events). This is the FBI’s first real initiative on the case since the agency closed it in 2016 — even as some former employees claimed the case remained secretly open.

After receiving the new evidence, the FBI tracked down the family and searched the property where the parachute was stored for four hours with more than a dozen agents, Gryder said. The unique changes to the parachute could hold the key to the value of the new evidence in the more than 50-year-old case. The FBI knows the original parachutes were modified by Earl Cossey, an experienced skydiver who worked for the FBI until his murder in his home in 2013. If the new find matches what they already know, it could boost the search for the real DB Cooper.

The DB Cooper case has taken on a mythic quality, with numerous theories put forward by amateur sleuths online, in books and in documentaries. A book from the nineties –DB Cooper: The Real McCoy—even claimed McCoy was to blame, but the book was withdrawn from print after Karen filed a lawsuit for defamation.

On November 24, 1971, DB Cooper – he called himself Dan, but the media misstated the name as DB – paid $18.52 in cash for a one-way ticket to Portland, and boarded Northwest Orient Flight 305 without offering any identification (due to a lack of regulation at the time).

Carrying a briefcase and a paper bag, Cooper passed a note to a flight attendant sitting behind him mid-flight and whispered that she better look at the note because he had a bomb. Cooper opened his briefcase to reveal what appeared to be a bomb, and detailed his demands for $200,000, multiple parachutes and a fuel truck waiting in Seattle so he could take off again, bound for Mexico City.

After Cooper’s demands were met, the planned 30-minute flight was extended to a two-hour loop over the Puget Sound while the ground crew prepared. Cooper released the plane’s 35 passengers and some crew members and then dictated the flight path and aircraft configuration to the remaining crew, demanding specific speeds, flap angles and more. When these negotiations were completed, Cooper and the four remaining crew members left again.

Somewhere over Washington, Cooper then opened the back stairs and parachuted out of the plane, but the exact location and timing of that jump is unknown. Immediate searches turned up no evidence, and over the years experts have been unable to determine an exact search area due to the many variables involved in the night jump.

One of the few pieces of real evidence Cooper left behind was a $1.49 clip-on tie from JCPenney, which is in the possession of the FBI. Investigators sued the government for access to the DNA and particles left on the tie, but to no avail.

Having the actual parachute would greatly expand the evidence in the case.

McCoy is an intriguing suspect – one who was later passed over because many FBI personnel had come to believe that the real DB Cooper died in the jump by the time McCoy surfaced as a possibility. And McCoy didn’t quite match the physical description, as he was much younger (27 years old at the time) than the original estimate of Cooper’s age as mid-40s.

However, McCoy is said to have had the courage to commit the famous crime. He proved it in April 1972, when he successfully pulled off the skyjacking of a United Airlines flight after demanding $500,000. He boarded the plane in Denver and was able to divert it to San Francisco, comply with his demands and force the plane back into the air. McCoy then jumped out of the plane over Utah and was arrested by the FBI within three days thanks to an anonymous tip. That tip then led the FBI to a waitress who recalled serving him a milkshake at a roadside hamburger stand the night of the skyjacking, and a teenager who said McCoy paid him $5 to take him from the kiosk to drive to a nearby city. Eventually, they were able to match his fingerprints to those left on the request note.

McCoy was arrested after the FBI raided his home. He was sentenced to 45 years in prison, but eventually escaped from a maximum security prison and evaded arrest for three months until he was shot by police in Virginia in 1974.

The parachute offers the best chance at evidence that could possibly link McCoy to Cooper. “This,” said Gryder, “will certainly prove it was McCoy.”

Tim Newcomb is a journalist based in the Pacific Northwest. He covers stadiums, sneakers, equipment, infrastructure and more for a variety of publications, including Popular Mechanics. His favorite interviews include sit-downs with Roger Federer in Switzerland, Kobe Bryant in Los Angeles and Tinker Hatfield in Portland.