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anyone know what happened :(

Channing Armstrong passed away yesterday evening around 5:30 in central california. He and a close friend had been quite active lately, exploring new cliff options in the local area. That morning they opened a beautiful cliff: 180ft with a long canopy flight in rolling green hills. In the afternoon, they elected to scout another exit in the same range.
The cliff was 140 ft above a steep talus with a large meadow at the bottom. Channing went first.
He chose to static line without a pilot chute for backup.
Using a piece of spectra and a rock as an anchor, he rigged one piece of brake-chord to a loop in the middle of his bridal, and a backup piece of brake-chord to the pc attachment at the end of the bridal.
Upon exit, his container was opened, but his canopy was not brought to full line-stretch. My understanding is that no opening shock was experienced.

Local search and rescue was contacted immediately, while myself and two other jumpers made our way to the sight. Channing's partner made his way down, and sent us a gps waypoint of their location.
All efforts to retrieve him went well, and we had everyone off the mountain within a few hours.

Confusion still remains as to why two static lines failed to function properly. If a better understanding is found upon inspection of his gear, I will be sure to update.

My deepest sympathies go out to his family. He was a good friend, and he will be sorely missed.

Sorry to hear about this incident.

I'm very interested to hear the details. Its always worried me that cutting 2 pieces of break cord from the same spool could result in disaster. Whether its from a bad spool or possibly just a bad section, there's a pretty good chance that if its messed up in one section, you could get 2 pieces of bad stuff.

Thanks for the update.

Fly free friend

I knew Channing and this is terrible to hear.
The reason people want to know what happened is to prevent this from happening to more good people.
This was totally avoidable. He was experienced with what I would assume experienced people.
Improved canopy performace are you serious?
Never static line without a pc!!!!
The first line broke before line stretch then by the time it got to the backup at the end of a 9 foot bridal it breaks instantly with that much force.
Always backup your back up at the middle point not the end of the bridal.
Always use the biggest pc you have as a back up.
This could has saved him.
I am sad and agree these mistakes contunue to happen.
make sure if you doing low jumps do it with the best most effective way known and tested.
bsbd Channing

This.

Talk about a preventable tragedy.

Wow. My condolences to Channing's family and the folks over at Hollister.

I'm racking my brain for how this could have failed if it was rigged properly. Please provide an update and pictures/diagrams of how this was rigged if possible.

I do a fair amount of low static line. I've tested a few common methods and found that they all perform similarly well if rigged correctly. My favorite method of getting off of a critically low (arguably too low to freefall) object is by PCA from another experienced jumper. If I need to remove my PC to make the glide to the LZ and there are other jumpers at the exit point I'll opt for a double handed PCA backed up by a SL to be triple sure that I'll make it to line stretch.

This is just off the top of my head as I type.

The first thought that came to mind was that it was pretty low and wouldn't it have been nice if he had done a direct bag instead. No one seems to do direct bags any more. I guess it's just a product of the current technology. Maybe some one should set down and build D-bag specific rigs. But that means that there has to be a friend to D-bag him. I suppose that if the conditions were right you might be able to set up a fixed leave behind d-bag if the situation permitted two anchor points. Then I started thinking about some of the carry away d-bag systems the Waymore uses in it's drop testing. They do aerial delivery testing rolling pallets out the back of a sky van. If the pane is not set up with a net below the elevator then they use a direct bag system that caries away on the drogue. It D-bags the eight foot drogue for the 1000 lb pallet. The line unstow off the bag. The last stows open the bag. The canopy comes out. When the canopy comes out it starts to unfold and when it extends the apex pulls on a line that goes up the center of the bridle like a kill line and releases the bridle from the plane. So you've got full strength of the bridle to the bag then a very small release force but it can not occur till the canopy is at least at full line stretch. You could have a break cord back up but it would be within the bag and it could not even be loaded at all till the canopy was all ready at line stretch. It's a little more complicated with two attachment points. What if one hangs up etc. Now you've got a crazy yank to the side... I don't know, it was just a thought off the top of my head.

Lee

I remember a while ago when two people died in a year because they used a pullup cord to help pack their PCs, and forgot to remove it after packing. My thought then was 'Are you f-ing kidding me? Why?' This feels the same.

I think this video should be included with this topic for awareness purposes.

https://www.youtube.com/watch?v=6q5TZgvIz14

Did anchor fail? Did spectra cut SL ? Ive used dacron as a leader, it has more elastic properties.

( heard break cord was old and pulled apart- not cut. Typical knot was not used.)

BSBD

I guess this wont be the last fatality due to not having a pilot on a packed rig. I was strongly advised to staticline without my pilot by another american jumper. And yeah D-bags seems to be a thing of the past. I am currently playing with top skin assist so i can use this for the borderline jumps.

The ol' that's Black Death line of reasoning, personally I have a lot of static lines that I have done with out a pilot chute backup for varying reasons, and I have done many static line experiments with different break materials in controlled settings using every physics calculation I could prove mathematically to be safely executable within reason and my own personal acceptance of risk and safety, yes in this case it seems a PC back up could have saved his life, a Dbag is another option that if executed properly could have netted a better outcome. or it might not have, we all accept risk differently. No technique in base is fool or genius proof. I am thankful to have known and enjoyed Channing's company. And I hope to learn something from the specifics of what happened.

What was his reasoning?

From what i could make of his vague story was that he sees the pilot as snaghazzerd. but this sounds so ridiculous that i must have misunderstood the bloke. The only thing he made clear to me was that he was no fan of staticlineing with a pilot.

An inspection of his gear shed some light on the events that unfolded.
One length of break-cord was strung through a loop tied ~1 ft. from pc attachment. No knot was present suggesting that the knot he tied may have slipped free. (note:there was a ~30% nick in the break-cord about 1/2 inch from the end.)
Tied to the end of his bridal was a second length of break-cord. This piece was very confusing, however, we believe that he used two shorter pieces tied together to make one length. He then tied that to the spectra, and then again to his bridal. We believe this cord broke right at the edge of the intermediary knot between the spectra and the bridal loop.

I have attached a crude rendering of the believed set-up and outcome.

The reason that the first knot may have slipped free remains a mystery.
As to why the secondary static line broke prematurely, several factors may have contributed.
1. The condition of the brake-cord appeared old and degraded.
2. It was reported by his partner that Channing broke his break-cord apart, rather than cutting it. This may have compromised the integrity of the break-cord prior to its use.
3. Both his primary and secondary static line setups were far towards the end of his bridal, potentially causing higher dynamic forces when loaded.
4. The direction of force applied to the cord as it entered the intermediary knot between the spectra and bridal may have reduced the tensile strength of his break-cord.

Although all his lines were removed from the tail-pocket when he came to rest, his canopy was found with the tailgate still intact.

It is with great sorrow that I report this. Channing was a good friend and coworker. His smile was infectious and his sense of humor unmatched.

Blue Skies...

And never static line except with a simple and straightforward attachment. See here for Theresa Tran's 1996 death for another preventable-tragedy example of why you never jury-rig or otherwise deviate from a straightforward attachment... unless you seriously research and test a variation so you know exactly what you are doing.

Case in point: Felix Baumgartner's 1999 "Jump from Jesus" above Rio.

It was only 90 feet to the base of the statue, so he had to static line, so he and his mentor/coach Tracy Walker experimented with different materials from a 130-foot bridge over water because even a standard S/L setup would not do.

They settled on a black garbage bag because it would stretch a lot before breaking, thereby guaranteeing full line stretch and canopy stretch before breaking. They repeatedly tested this setup over water to make sure it would work. And as Tracy told me when I interviewed him for the Skydiving Magazine story I did on the jump:

"The most interesting thing was teaching Felix all the knots he needed to tie into what he thought he had to tie into, and how to attach the deployment system -- the garbage bag -- to a stable place... so I taught him all that, and then he dirt dived climbing and tying the knots.... the dirt dives were unbelievable; we even have some video of that."

One final point on this is to riff on Rigger Lee's d-bag discussion.

To me, a d-bag/static line combo is the bomb! This setup has been proven via more jumps than any other system in history, because that's what all American airborne forces have used for 60+ years. Here is how it works:

--Static line clips to aircraft cable at one end.

--Static line hard-sewn to top of d-bag at the other end.

--Canopy attached via 80-pound break cord inside the d-bag at the hard-sewn static line attachment point.

--Full line and canopy stretch is guaranteed before the break cord breaks.

Condolences to Channing's friends and family.


44

Such a setup is inconvenient for base, too much hassle. Unfortunately that is how mainstream goes. The convenient way, not the safe one. That is why we have FJC off SD cliffs and pack volume the main criteria for reserve canopy size.

one shouldnt use an Aramid, only polyan aramid onlmids for Break cord.. though i think that thy e margin for for error was (was) waylow, usinthg an aramid only exacerbated the problems. Spectra? that is like a chain of molecular structure, no elongation. Knots do not work well in this this range. nor does maintaining tension. i doubt that a pc would have helped. it sounds fxxk from the getgo. THe Jesus jump used a polytween, garbage bags rolled for the breaking point calculated for the speed of deployment.There is a huge diff between in 1m vs 2.8m. do your physics. Lee has it correct. DB. sorry that it has to be learned in such a hard way.
spectra is known to be a victim of sharp edges. Why dont you know?
take care, space

Thanks for the report.

What strength break cord was he using?

I've also been warned against using some nylon on nylon in static lines, after I ran out of break cord for my take-away system and was considering using 16lb E-thread. I was warned it could to cut the dacron I was using in my system when loaded - putting a rapide link between the parts would fix that.

Thinking about this was just making wonder if it would be possible for one loop of break cord to cut through another loop of the same cord before either breaks.

But from your description it sounds like whatever happened, the static line detached as soon as it took the weight of the canopy.

I have always tied on to the end of the bridle, seeing short lining as only necessary when low.This is something I will re-evaluate! Maybe some pull force tests on BASE pins / bridles.

Using a 'reasonable' diameter, smooth anchor point for the break chord makes sense to avoid stress concentration.

Fresh break chord in good condition, cut, leaving tails of a few inches either side of knot..

I remember the story of the Oz 'electrical tape' method being used in the chilly UK, that nearly ended in tears, PC saved a life that day..

Nylon is the way to go. Who warned you, They are false. simple physics dictate that things arent cool.
with a piece of 550 i can burnthrough a riser in 3 secs mini riser i mean.
the accel between 0 - 3m is enormous. polymids adjust. armids dont.
tcs

The system I use has a finger-trapped piece of dacron tied to a rapide link with break cord.
My idea was to substitute the break cord for doubled over 16lb E-thread. I was warned that the E-thread (being very thin) could cut through the dacron - whereas the break cord wouldn't because it's fairly wide and soft compared to E-thread.
Made sense to me... ?

I have always felt electrical tape is the best and safest option, due to its strong stretch before breaking and known built in redundancy (multiple wraps) that is wholly within my control. This all makes it very low risk of failure. Good to know there is a temperature related failure possible. Maybe good quality branded tape would prevent this (which is what I always use anyway).

Have there been any other know incidents with electrical tape?

https://www.youtube.com/watch?v=6q5TZgvIz14

For what its worth;

I almost went in years ago due to my electrical tape breaking/ slipping on a wet railing. i was saved by my 48. Made a very big dent in the sand under the bridge...

what did I learn, either use more wraps (if you're a real aussie), or go to break cord (and practise your plfs)

Stoney

Almost makes up for the fact you've never nutted up and freefallen that thing. Almost.

 
Condolences to all Channing's friends and family. Dying sucks. However, dying an easily preventable death, to me, sucks worse.

I've never understood the need some people have to keep re-inventing the wheel, when perfectly functional methods of operation already exist. Especially in conditions where failing means you will die. If this jumper had used a standard CWY SL with break cord and a PC for back-up, with the info available now I'm pretty sure he'd be alive. That I find really sad.

Is it a pride thing? That you have to show you are capable of doing things differently, in your own way? Or find it that hard to ask for advice, in fear of losing face (ridiculous, I know)? What is the driver in this behavior? Personally, I've always tried to find the best available info on my own and ask around for opinions, for the sole purpose of trying to NOT fuck up.

If I ever go in due to being unnecessarily stupid, please tear me apart on these forums, someone might learn something.

Kerkko
BASE1184

There is one thing i will note about that video - they recommend backup at 9 ft, but in the course of the video show a drop test that shows that a backup at 9 ft is ineffective - a 5 pound weight allowed to drop 9 feet will have enough energy to break two break cord loops. Only logical conclusion I can make is your backup break cord should be halfway up your bridle as well...

Agreed, but its probably to keep excess bridal and your PC clear and in a good spot during deployment more than anything else.

I do two loops (1 bigger 1 smaller) half way down the bridle. I also like to use a small hard link on the bridal so the tension on the break cord doesn't burn it with repetitive use.

Everyone should go out and buy a roll of break cord to test which setup they are personally happy with. I know which knots I prefer, where I like to tie off and the way it reacts when dry, or wet or other cases. It's good to test these things in a safe way at home before using it in the field.

Interesting point, and from what we know from physics and science and stuff, the higher the speed ( i.e more distance travelled) equals greater breaking force, anyone else care to weigh in on that? Makes sense if the primary fails, sure as shit your secondary at the bridle attachment was just a few extra seconds of pointless dicking around on the exit point.

 
The vast majority of S/L jumps I have seen performed had the break chord at the end of 9' bridle. The extraction force of the pins and canopy is luckily not as 'abrupt' as trying to stop a 5lb pound packing weight.

It is definitely an area than needs further research having claimed a few lives..

Short lining will be safer, leaving the PC a must.

Not exactly. The reason for a secondary is if you've done something that has lowered the strength of the primary (cut, frayed, poor knot, sharp attachment point etc.), rather than having done something that's raised the required deployment force. If that makes sense.

Bottom Line Up Front: A break cord at the end of the bridle may not have the exact negative consequences you think it does. If you use a water knot with LONG TAILS, and the break cord is not worn, it should deploy your parachute without issue. I am not advocating a static line at the end of the bridle, only suggesting that other factors are more significant.

This video was posted before, and I think it is important to address some of the (potential) inaccuracies that it perpetuates. I posted it about 6 months ago, and someone challenged its validity, which caused me to think some of the physics involved in the "5 pound" model.

I understand this all has a very long, scientific feel to it, but I ask that you just stay with me. I think it presents some pretty important concepts that will hopefully help you understand the powers at work when you static line an object.

The tests that were conducted are 100% valid, a 5 Lbs. weight dropped from 9 ft. will snap the break cord. However, you must understand the exact physical implications this has. The only thing this proves, is that a 5 Lbs. weight traveling at 17.0 ft/s will impart enough force over a 9 foot bridle to exceed 80 Lbs.

Fact: If we are to build a rigorous model, we must evaluate the force on the break cord as a CONTINUOUS, and not a DISCRETE model. The tension in the bridle is also equal and opposite for both sides (as in an ideal physics model). In layman's terms, the force applied through the bridle gradually increases in equal amounts and opposite directions of the bridle over time.

Assumption: The pin tension of the rig we are jumping is 10 Lbs. In layman's terms, 10 Lbs. of force in the bridle will open the rig up, deploying the parachute.

If we make a static line jump with a knotted, but otherwise unaltered piece of 80 Lbs. break cord, the break cord will hold until a specific force is put on it, at which point it will break. This specific force is determined by both the strength of the cord (80 Lbs.) and the efficiency of the knot that is used. Assuming we use a water knot (65% effeciency, source listed at the end), the break cord will hold until 52 Lbs. is put on it.

If the break cord is holding until 52 Lbs. is applied, and an equal force is transferred through each end of the bridle, and the tension in the bridle gradually increases, the pins will reach 10 Lbs. tension before the break cord reaches 52 Lbs. of tension. Thus, the pins MUST release before the break cord breaks.

Based on this, the only thing that could cause a properly secured piece of break cord to fail in a static line deployment is a faulty knot (whether inefficient or improperly tied) or a weak piece of break cord.

You have complete control over the knot(s) tied before you leave the object. This should not be an issue. If you are not 100% confident in what you are tying, get help. This is too easy to figure out with the help of a buddy (or the internet, but personal instruction is highly preferable). You do not have 100% control over the strength of the break cord. This is why I like one of the previous concepts mentioned above of tying a second piece of cord from a different batch. You mitigate the risk of a bad batch of cord. In this way, you reduce your risk.

Regardless of all of this, I want to get to the point I presented in the beginning. The concept that a knot tied at the end of the bridle will result in a broken cord is not quite accurate. Traveling at 17.0 ft/s, 5 Lbs. of near instantaneous force will break the cord. However, the expansion of the parachute, and the extension of the lines DOES NOT impart the full weight of the parachute. The force imparted after the pins are pulled is quite dynamic, and such a simple test cannot capture the complexities going on. Rather, I believe a static line tied with a water knot at the end of the bridle using a good batch of break cord should hold to line stretch.

I have not done any physical testing to prove the validity of the model I propose. However, I strongly believe that it is true in its entirety and welcome any dissent.

Oh by the way, I'm an undergrad majoring in physics right now. I realize telling you this might make me sound like a douchebag, but hopefully it convinces you I'm not totally full of shit.

My source for the strength of a water knot is listed below:

https://books.google.com/books?id=jB7YTRVt5coC&pg=PA101&lpg=PA101&dq=water+knot+efficiency&source=bl&ots=t-cSdlmYp4&sig=k5Hu5V3OSq0x40Q2wu1KvqhlBaY&hl=en&sa=X&ei=UZ3VVLmACsWHsQTztYKoCA&ved=0CD4Q6AEwBQ#v=onepage&q=water%20knot%20efficiency&f=false

The bottom line is that the BASE jump attempted here allowed for ZERO margin of error. Why? Because it was an extremely LOW place for any form of parachute deployment.

Sure, we can analyze it a million different ways, we can argue about break cord VS electric tape VS direct bags VS unpacked jumps VS PC/ no PC, but the fact the remains that this was a category of jump, just like LOW wingsuit terrain flying or LOW tracking that allows for absolutely NOTHING to go wrong. No gear mishaps, no pilot errors, nothing.

I watched the apex video, Todd is a smart guy. I listen to James, he is a smart guy too. We are humans. We are not 5 pound weights and we are not 10 pound weights. We are humans. Humans error. Unspotted variables exist.

The choice of jump was very hardcore.

It is important to leave some margin.

My most sincere condolences to those close to Channing.

No truer words

Your model is totally off. It isn't the extraction of the pins that breaks the cord prematurely, it's the shock load of the extraction of the canopy from the pack tray from what I understand.

Being IN undergrad for physics is NOT any sort of qualification. It's the factors you don't know that'll kill you.



Also, just as a general comment for this thread...people keep talking about the PC being absolutely necessary and making it a preventable tragedy. I totally agree that you should always have a PC on the end of your bridle for static line jumps, BUT when you get down into the ultra-low static line range (<120'), would it really do anything (especially from 100')?

It's the slack in the system and redundancy. You should have absolutely minimal slack to exit the object. I always do a figure 8 (on a bite) on my bridle to attach the quicklink/static line such that there is just enough slack for me to jump without prematurely popping my pins.

I think for the sub 120' stuff the PC is more, if it breaks partway to line stretch it will help finish extraction. If you had a premature break while the canopy is still effectively in the tray you're probably pretty fucked whether theres a PC on or not.

Ian: two things to consider

1. It appears that the break cord in this fatality popped the pin but didn't extract the parachute, which you mention no provisions for in your view of how break cord physics work.

2. That video is not as incorrect as you would think or hope. At the end of your bridle is a parachute. It is a weight, that comes to an abrupt stop and all of the energy of that abrupt stop minus some elastic properties of the system ultimately transferring through the break cord into the object you jumped off of. The break cord must survive this transfer.

Watch your static line video in slow motion. You will notice the parachute stays in place after extraction and until line stretch, when your static line breaks and inflation occurs. This is the intended sequence of events. But it also means the parachute must be arrested from freefall. And it weighs more than 5 lbs.

You're right. I was initially under the impression that the pin tension was considered as a factor for the 5 pounds of force, rather than lifting the parachute out of the pack tray. I realized that about half way through writing my wall of text. I decided to leave it in there because I believe what I said was still accurate, and it at least gives merit to the argument that pin tension is not a factor. Regardless, this was not the point of the video, so what I said about pin tension is somewhat moot.


Once again, I totally agree with you. I don't have any qualifications that should convince you to agree with me. However, given the length of what I wrote, I figured that mentioning my background might encourage people to look over it a bit rather than just glossing over it as a rant.


I believe that the extraction process probably puts more force on the bridle than popping the pins (which, I believe, is what Zebu was saying). If that's true then it's reasonable that the force of popping the pins could be overcome, but the force of extracting the canopy could not.



I watched 4 videos of static lines frame by frame. I think you make a compelling argument. The canopies do tend to stop pretty abruptly. The question is, how abruptly? Because of the malleable nature of the fabric, there is definitely some unfolding that occurs as it is extracted. This would almost act like a shock absorber as the canopy unfolds. I think this makes looking at it from a purely mathematical perspective nearly impossible. More experimental testing needs to be done.

Some of the canopies unfolded more cleanly than others as well. It was like some of them were neatly stacked like an accordion, and others wadded together like dirty laundry. From what I know about the jumpers relative packing skill (admittedly highly subjective), it appeared that those who packed more cleanly had canopies that freely unfolded, likely absorbing more shock.

I will be in Idaho in March, and I'd like to do and video tape some SL jumps with the break cord at the end of my bridle.

If this is true, the takeaway would be that neater pack jobs are less likely to prematurely break the breakcord. My old mindset for PCA/SL was that packjob is less important on "anchored" jumps since heading performance isn't as much of a factor (assuming you buy the argument that heading performance is more a factor of the anchor position than anything else).

Maybe that's worth rethinking, at least on SL jumps.

Then again, maybe we're over thinking this way too much. The easy answer is to always use a PC and keep your SL jumps at 150+ feet.

All of the stuff I wrote is definitely nothing to lose sleep over. A much simpler solution is just making the slack in the bridle as short as possible and not worrying about what happens when you attach at the end of the bridle.

I'm just trying to give an explanation for some of the factors that I believe that video overlooks.

Ya'lls - go do a dozen PCA's and figure out what the extraction forces do at various points post-exit. It's really a pretty easy to do real-life experiment. Just need to get out of those armchairs.

The only folds that undo before line stretch that have a significant impact are the last, vertical ones (across a horizontal axis) to fit your pack job into the container. However, consider that ~13/2.5 = ~5. So basically the 5 lb weight in that video can be thought of to represent the force required to arrest the first third of the canopy that does not unfold in a meaningful way. After which two more folds of fabric must be stopped midair, both still travelling at the same speed.

Fairly general proof of concept, yes. But the point remains - the apex video has a solid point that attaching a break cord at the end of a bridle substantially increases the risk of break cord failure and your odds of survival increase if you attach primary and backup halfway up the bridle. And their test, while it does have some safety margin to "real world" with some additional elasticity not accounted for, is actually fairly on point.

This video https://www.youtube.com/watch?v=U8-dcw8Vy6o is from about 15 years ago. First time we noticed a premature break. Not a huge deal since it broke after extracting things 70% or so, it was 165 feet and had a PC back up yet it was still interesting at the time.
Also, when you watch the extraction in slow-mo, the angles the canopy and lines take on is also interesting. Attached is a few still pics from 11 years ago showing what I mean the about the angles of the lines and canopy.

I have watched this video for years and always wondered why shrivel flap was moved?

Why is there 4 ft of bridle between flap and canopy? Watching video again looks like 3-4 feet of bridle between tie off and shrivel, then another3-4 feet after shrivel to attachment, canopy falls 9+ feet before tension.
*also clear by pics*[/image]

poor decision making was the issue here...before the static line was even rigged. Getting into semantics over rigging of static lines, however entertaining, is pointless here.

Channing was an awesome dude to be around, wish I could throw oranges at his head some more...lata buddy :(