Siblings claim dad is mysterious DB Cooper after 'one-in-a-billion' discovery in his attic

More than five decades on from the legendary 'skyjacking', the identity of DB Cooper still remains a mystery.

But bombshell new evidence could finally shed some light on the cold case which has baffled investigators since 1971, according to an amateur sleuth.

Dan Gryder claims that he got his hands on the parachute which the elusive hijacker used to pull off his elaborate escape from the Boeing 727 aircraft a whopping 53 years ago.

Despite a Netflix documentary being created about the notorious case, DNA breakthroughs and countless experts weighing in on it, the identity of DB Cooper still hasn't been uncovered.

The unknown individual boarded Northwest Orient Airlines Flight 305 on 24 November, 1971, from Portland, Oregon, to Seattle, Washington.

The 'nondescript' man called himself Dan Cooper while purchasing his one-way ticket with cash at the ticket desk.

During the journey, he informed a flight attendant that he was carrying a bomb before demanding $200,000 (which is equivalent to over £1 million in today's money) and four parachutes.

DB Cooper dived out of a plane in November 1971 and has never been found (FBI)

After receiving the ransom and allowing the passengers to deplane in Seattle, he ordered staff to refuel the plane and fire up the engines once again.

Around 30 minutes after taking off for a second time, the mystery man opened the door of the aircraft and parachuted out into the night somewhere over southwestern Washington.

Only one clue pointing to his identity was left behind at the scene; a tie from the US retail chain JCPenney.

It meant investigators were left to mainly work with the testimony of those who had been onboard the Northwest Orient Airlines flight.

However, the true identity and subsequent fate of DB Cooper have still never been determined. But according to Gryder, that could all be about to change.

The content creator, who has been looking into the cold case 'off and on' for the last two decades, claimed that the children of one of the only suspects presented him with DB Cooper's parachute.

Siblings Chanté and Richard III 'Rick' McCoy claim that their late father, Richard Floyd McCoy II, is the bloke who pulled off the hijacking.

Dan Gryder said the parachute was a 'one in a billion' find (YouTube/Dan Gryder)

He was considered as a 'serious suspect' in the case by the FBI after carrying out an almost identical hijacking in April 1972.

McCoy hopped on a flight in Denver, Colorado, before pulling out a weapon and ordering airline staff to secure him four parachutes and $500,000 (£396,738).

Like DB Cooper, he also exited the aircraft using a parachute. McCoy was killed in a shootout with FBI agents in 1974 after he escaped from prison.

Chanté and Richard say they got in touch with Gryder following the death of their mother as they feared she might have become implicated in the investigation.

According to the YouTuber, the brother and sister found the modified military surplus bailout rig in their parents storage.

And he's pretty certain that it could hold the key to the more than 50-year cold case.

"That rig is literally one in a billion," Gryder told Cowboy State Daily.

Both the children also believe that McCoy was the hijacker.

One of the unused parachutes Cooper requested but never used (FBI)

The parachute has now been given to the FBI, although there has been no official updates on the DB Cooper case online.

But sleuths hope that this development could give detectives the push to take another look at the hijacking and hopefully get to the bottom of it once and for all.

Gryder shared a YouTube video on Monday (25 November) discussing the update, while adding that the FBI had been exploring the latest discovery.

"This is the rig he used... we just solved it," he said.

The FBI's last update on the DB Cooper case came in July 2016, when it was announced that officials would no longer be 'actively' investigating the hijacking.

However, it did state that the emergence of 'specific physical evidence, related specifically to the parachutes or the money taken by the hijacker' should be immediately reported to the authorities.

Gryder believes that the next natural step would be to exhume the body of McCoy to carry out DNA testing.