DB Cooper Case Could Close Soon Thanks To Particle Evidence

It’s one of the strangest unsolved cases, and even though the FBI closed their investigation back in 2016, this may be the year it cracks wide open. On November 24, 1971, Dan Cooper, who would become known as DB Cooper due to a mistake by the media, skyjacked a Boeing 727 — Northwest Orient Airlines Flight 305 — headed from Portland to Seattle.

During the flight, mild-mannered Cooper coolly notified a flight attendant sitting behind him via neatly-handwritten note that he had a bomb in his briefcase. His demands were a sum of $200,000 (about $1.5 M today) and four parachutes once they got to Seattle. Upon landing, Cooper released the passengers and demanded that the plane be refueled and pointed toward Mexico City with him and most of the original crew aboard. But around 30 minutes into the flight, Cooper opened the plane’s aft staircase and vanished, parachuting into the night sky.

In the investigation that followed, the FBI recovered Cooper’s clip-on tie, tie clip, and two of the four parachutes. While it’s unclear why Cooper would have left the tie behind, it has become the biggest source of evidence for identifying him. New evidence shows that a previously unidentified particle on the tie has been identified as “titanium smeared with stainless steel”.

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Better Mousetraps (or Screw Drives) Don’t Always Win

I’ve noticed, lately, that slotted screw heads are all but gone on new equipment. The only thing that I find remarkable about that is that it took so long. While it is true that slotted heads have been around for ages, better systems are both common and have been around for at least a century.

Check out those cool threads.

The reason slotted heads — technically known as the drive — are so common is probably because they are very easy to make. A hacksaw is sufficient for the job and there are other ways to get there, too. The only advantages I know of for the user is that you can easily clean a slotted drive and — possibly — use field expedient items like butter knives and quarters to turn the screw. I’ve heard people claim that it also is a feature that the screwdriver can pry things like paint can lids, but that’s a feature of the tool, not the screw drive.

The disadvantages, though, are significant. It is very hard to apply lots of torque to a slotted screw drive without camming it out or snapping the head off the screw. The screwdriver isn’t self-centering either, so applying force off-axis is common and contributes to the problem.

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