I was impressed by this womans story (below) and I'm surprised the FBI hasn't used the more modern and substantially improved forensic abilities of todays scientific policing, to match up the DNA of Lynn Doyle Cooper, to the evidence they hold from the hijacking, such as D B Coopers tie.
Today, we have many "cold case" crimes from 20, 30 and 40 years ago, being solved purely by the application of current, high-tech forensic testing being able to match DNA samples that were previously unable to be sampled and matched.
DB Cooper case 'solved': FBI tells niece of skyjacking suspect after 'matching' fingerprint | Daily Mail Online
Marla Coopers story has the ring of authenticity, an uncle who disappeared for a couple of days, who showed up injured (as you would, parachuting into timbered terrain in the dark), and the money being lost during the parachuting, jells with no currency with the recorded serial numbers on them, ever showing up.