How long would a parachute “survive” exposed to the elements

Inspired by this thread: https://boards.straightdope.com/sdmb/newreply.php?do=newreply&p=21333456

I don’t necessarily believe that DB survived the jump but if his chute would have hung up in a tree, how long would it last exposed to the elements? What about in a creek?

By survive do you mean be recognizable as a parachute? I’d think a nylon chute would still easily be recognizable as such from Dan (DB) Cooper’s jump.

nylon fabric degrades rather quickly in sunlight (UV degradation). I think I remember nylon rope degrades slower for some reason. All nylon resist s milldew and other water driven rot. So maybe parachute cords in the mud would have lasted longer then the fabric in the trees.

47 years on, I think the fabric would be long gone and the cord and webbing mostly so. The metal fittings of the harness would be corroded but still easily recognizable.

Yeah, I wasn’t coming at from a perspective of is it still there now. I’ve always wondered why the chute wasn’t found in the first ten years or so. Especially given the large number of people searching. Could it have lasted 10 years?

As noted, the bulk of the 'chute material degrades at a decent pace.

One question is: What stays up in the trees where it’s more easily seen?

There could easily be 200lb+ of weight pulling on the cords. Given some wind, snow, etc. pulling on the degrading fabric it wouldn’t be long and it’s on the ground. Then it gets covered in forest litter. Finding it once it’s on the ground is really difficult.

That assumes the parachute was opened. It’s widely believed that Cooper could not have been able to stabilize himself and correctly pull the chute open. I.e., it was all freefall straight to the ground.

Compare with the Steve Fossett case. Disappeared in a light aircraft. Extensive search in a less dense forest (finding other wrecks along the way). Finally located a year later when a hiker found his wallet. Only two bones were found: a half mile from the wreck.

And this was a (small) plane.

People who don’t know wilderness vastly underestimate how hard it is to locate something like this when you are deliberately searching.

I apologize if this should be a separate topic, but reading the linked Wikipedia article (and the various news articles linked to it) about the search for Fossett led me to a question:

There are almost off-hand references to the searchers finding eight other wrecked airplanes in the mountains where Fossett was lost and eventually found. The articles mention that the wreck sites were examined during the Fossett search only long enough to determine that they weren’t the Fossett wreck, but then made vague assurances that the authorities would return to those sites later to hopefully resolve the mysteries of other lost airmen.

A few of the articles focused on an Oakland businessman lost in the area in the 1960s, and his family’s hope that they might obtain closure. But the Wikipedia article on him ends with this:

Also, my googling of “eight airplanes found in Fossett search” showed no significant later developments.

So, does anyone know if the “no followup” remark is still true? Did any families of lost airmen other than Fossett’s own ever get closure as a result of the Fossett search?

Why would he not have been able to deploy his parachute?

Note that you do not have to be stable in freefall for a parachute to function properly. It helps, but isn’t actually all that important.

Also, assuming he didn’t land in a tree, he would almost certainly have buried the parachute so it couldn’t be spotted from the air. And even if he did land in a tree, if he could climb down he might have first cut up the canopy and taken it down with him if possible.

So the inability of searchers to spot his parachute really doesn’t mean anything.