Basejumper.com - archive

Hi!
followup to this thread http://www.basejumper.com/...um.cgi?post=2942373;, i thought its better to get a new thread here than post in incidents.



so here we go:
http://www.vimeo.com/26740577
jumper recognized the hesitation, and found a knot in the bridle, a bit below the PC after landing.

Besides having too little pin tension (that maybe contributed to the knot by giving free more bridle when pins were popped), the main reason for this was the pc hesitation that followed:
- the weak pull
- bringing the pc a bit forward before letting it go

no pc packing method would have changed what you can see in the video.

thanks to the jumper for letting me use his footage.

take care!
hirschi

Looked to me in the video that bridle line was essentially fully out before the jumper released the PC. I'm looking at 0:12 in.

What do you think?

Very interesting! Thanx for posting!!

Bridle entanglements have also happened on extremely short (even go and throw) delays, though. It's doubtful that the turbulence behind the jumper at go and throw really contributes to those, because there is really not much turbulence when the PC is deployed at 1 or 2 seconds.

> no pc packing method would have changed what you can see in the video.

That's a pretty bold statement. How can you be sure of that? I know for sure that I have not thought of every possible PC packing method, and then gone on to analyze what it's effect on every situation might be.


I think that the pitch technique is probably the leading cause of bridle entanglements. Since they occur on short delay jumps as well as longer delays, I think that the pitch technique is probably a larger factor than turbulence behind the jumper.

Could this be helped by some different PC packing technique? I don't know. It seems possible. I would certainly hesitate to rule it out categorically, simply because I don't think anyone knows enough to say for certain.

Why don't we bring back the spring loaded pilot chute?

It'll take care of this bridle knot and hesitation business.

It looked that way to me too.

It seems like if there was some way to stage the bridle inside the BOC, the flailing loop of bridle that causes the entanglement could be substantially reduced, which would also reduce the odds of entanglement.

I don't know how you could do it in practice, but picture if somehow you could feed the bridle through your hand as it was thrown (say if you were standing behind the jumper as he pitched, on the ground) keeping just a slight amount of tension so that the bridle never had any appreciable slack. It seems like a system that could do that in freefall would more or less eliminate the slack loop of bridle that entangles here.

well, let it put it this way:

what i really meant was that in the way the pull was performed, (-> weak, holding the PC a bit), the bridle would have been blown out with every PC-packing-method i know of.

That is right, however, in the video i posted, there was obviously a PC hesitation. (i was not stating that bridle entanglements always happen like this, but its just what happend in this case)


I think that adding some resistance (thats pretty much what you would have to do to achieve some staging of the deployment) to the bridle in the BOC (or wherever else) would lead to more PC hesitations (and would be contrary to having as lightweight PCs as possible).

ciao!
hirschi

I think you should throw the PC like your life depends on it instead of throwing like a 6 yo girl will solve what you see in the video.

WHY?? would anyone grab the PC and just hold on to it?

Blaming PC packing method instead of complacency and poor PC toss is B.S.

I'm not sure the "main" reason for this is the PC hesitation. I see several reasons. This is a completely out of sequence deployment!! The pins are both out before he lets go of the PC, which adds extra length and a perfect half hitch just waiting to lock up!

1)Those pins are WAY too loose!
2) Pulling the PC then holding onto it
3) Weak toss

Glad they made it

First: BASE 1361 is perfectly right ...

And what about the educational task here as other people and newbies read this too?

I believe that pc packing is more or less an own religion. And we know we shouldn’t discuss about religion.
But of course we should focus on the message of this thread instead of discussing a wishfull thinking that there once will be a good PC packing method.

Right now: There isn’t for all occasions ... whilst people died multiple times because they hadn’t been aware that a good throw outside the self creating bridlebow is life important.

So air resistance on the bridle has a major influence. And this starts from the first push into acceleration. Therefore focussing on an educated solution we shouldn’t make a difference if somebody had the problem after a 1s or 8s delay. It’s there and that’s the fact (also have a look on the added pics).

Most recent entaglements occured in track or wingsuit jumps. So it’s just natural to focus on this one more than on low speed stuff. We should therefore be thankful someone started this thread.

On the other hand, for the go and throw entanglements I would be cautious to compare cheries with berries here.
In low speed the accepted wind conditions, the bridle-pc setup and the throw technic are playing a major role. So we first must look at this factors before we judge the entaglement. At least it should be the easiest task to avoid an entanglement by intention here.

Anyway, on high airspeed pulls it seems evident now that a dangerous variabel is added by just natural and physic force. Well, I'm sure some of us knew it before ...
But maybe that’s all we need to be aware of to act even more souvereign on our next jump.
And since we increased our terminal flying in BASE jumping the last 10 years we should be clear about this as we don’t want an evolution of the clueless here ...

All the others can try to work on a supportive pc packing or bridle staging method. I’m curious about a new smart invention ...

:-)
M.

That's a nugget right there.

That video is amazing and gives a good idea of the chaos that may sometimes go on behind us when we pitch. Seeing that encourages me to post pics of this bridle entanglement, which I had assumed could only have been a result of me being a complete fucking retard. Which may still be the case.

I wish I had similar video to see how this PC-Bridle entanglement happened.

This happened on a handheld jump from a 300 foot bridge with less than a second delay.

Previous to seeing this entanglement, the only one I had seen was in a photo from the BFL.

Those photos made my stomach flip - Fuck.

Glad you are still here bro.

I got to ask??

WTF did you do on that jump to create that death trap??

I know the photo of which you speak of on the BFL, it was a Russian jumper in the Valley who "held onto his PC to signal he was going to dump"..... at least that's what I heard, wasn't there.

So what happened on that 300'?

Fair question. I even appreciate the tone of your question, because that is how it sounds when I ask myself. And believe me, I laid awake nights thinking the exact same thing after this jump.

I used the same PC and bridle handling method and pitch I have used on almost every handheld jump since 2007. (Bridle routed top pin, bottom pin, up across my shoulder, tucked lightly in the riser cover, down the length of my arm, between my index finger and thumb, s-folded into my hand, all the way to the crown of the PC.) The only change I have ever made in that is to route it bottom pin, top pin if I was packing for handheld and low.

I have no idea how the entanglement occurred. I only know that I was still accelerating after I pitched and I didn't feel the pins pop. I was lucky enough to grab the bridle on my first try and extracted the canopy that way. I couldn't do it again in a million years, and couldn't have done it that time if I had thought about it. There was only time to think, "Shit. Dead." I didn't even know I had grabbed the bridle until it was ripped out of my hand when the canopy inflated, leaving a nice "rope" burn.

wow

I got a boner looking at those photo's, is that normal??

What do you do with the ZP part of the PC?
Do you tuck it in your closed fist or do you let the material hang over outside of your closed fist?

Laters

Julian

I only know that I was still accelerating after I pitched and I
didn't feel the pins pop. I was lucky enough to grab the bridle
on my first try and extracted the canopy that way.

There was only time to think, "Shit. Dead." I didn't even know
I had grabbed the bridle until it was ripped out of my hand
when the canopy inflated, leaving a nice "rope" burn.

A W E S O M E !! Thanks for sharing.
I would have enjoyed that burn deeply.

"I only know that I was still accelerating after I pitched and I
didn't feel the pins pop. I was lucky enough to grab the bridle
on my first try and extracted the canopy that way. "

That's one of the most bad-ass Chuck Norris-esque things I've read in a long time, my friend. Someone needs to commission an oil painting of you in action on that fateful jump.

No sarcasm intended when I asked. Honestly a learning lesson here.

What another jumper asked it the position of the ZP when you go hand-held. Like a mushroom hat or tucked inside your hand as well??

@ 300' I would argue it's more Bruce Lee than Chuck Norris. Chuck Norris dies in Enter the Dragon........

I hate to endorse anything that matt g says or does, but this is an interesting way of packing a pilot chute to prevent some of this stuff. Havent tried it myself

http://vimeo.com/26274995

I S-fold the mesh on top of the bridle, then the zp on top of the mesh, until the whole PC is in my closed hand. Of course to do that, the S-folds of mesh and zp go beyond my hand on each end a few inches or I can't close my hand.

I also handheld my pc this way, s-fold the mesh, s-fold all the bridle on top of that, then work the xp down around all the guts, as if I were going to stow it. Then hold that, run the bridle up the container, soft tuck into the top of the side flap and then to my hand. And i still hucl the shit out of it. I've seen hand held videos of people who just open their hand and let go, my mentor taught me "Chuck that PC like your life depends on it" as earlier stated. Because it does...

I don't pretend it was anything more than luck. If I had missed the bridle on the first try, there would not have been time for a second try. If the same situation occurred again, chances are I would go in, so you can bet I will pay extra attention to my PC and pitch from now on.

@GreenMachine - As nasty as my hand looked, every time I looked at it, I grinned like a monkey.

+1
kudos.
great recovery!

Might be a good idea to throw your rig on, and have someone pull your bridle out to extension, hold it but not release the pins. And work for some muscle memory on how to reach your bridle, I know I am planning on this. Just one more for the arsenal, to being prepared for a holy fuck moment.

while this training can't hurt, will the bridle be taunt or dancing around in the burble?

head high/head low/flat & stable all can affect the bridle position as well.

this jumper became quite fortunate!

Wouw, congrats to your emergency deployment success.

You are the first one I get knowlegde of who survived with this almost too theoretical emergency technic! Bravo ...
That's for sure an iron cross first class for you.

That's also a hammer as we always practice exactly this scenario here during my FJCs. More or less with a smile as this shit is almost too fat for the fan ...

So where was the bridle floating at the moment you grabbed it?
I always say that someone who feels no deployment but rather to impact should role to the side so the bridle shows itself somhow beside and therefor is easier to grab whilst the canopy catches also immediately air when the pins pop. Theoretically ...
Well, we give a shit on an on heading opening then ...

On the other hand, as you softtucked the bridle on your right shoulderflap, how resistant was this soft tuck and how many wind from which direction was present at that day?
Maybe your softtuck fucked up at the moment you moved into the jump and so gave a fair amount of bridle slack free behind you which definately supported the self knoting of it. Maybe move supported by the throw or wind supported by strengh and/or direction.

Of course you eliminated this already for the future as you pack your pins now bottom to top.
I always recommend to use a 3 inches velcro rather than just a soft tuck. The velcro also compensates bridle oscilation during handheld jumps and stages the bridle stretch in a positive way. It also absorbs unintentional "swimming moves" if an exit is not optimal and your reflexes work for stabilizing.
At least you have less bulk of bridle in your hand as some of it is routed parallel along the container.
And so less bridle can float around the pc during lift off.
Well, the velcrorouting also has negative points as you need to be aware of how you move in a tight or structural invironment.

Thanks a lot for sharing all this infos. I will copy your pics to show them to my future padawans.
Untill today I only saw pictures of PC entanglements from that kind where the people didn't make it ...

I also attach you here a little story I observed in the past. Lukas Knutson (a very experienced and souvereign BASE jumper at his time) was having a discussion about hackey sacks on his pc which later maybe had been the key to his tragedy.
If he would have known what we know today about bridlebows and entanglements he maybe could have had the chance to avoid the trap.

Take Air
:-)
M.

PS,

... even in the video section of this webpage you see a total different handheld configuration at 1:03 to 1:15.

(relying on http://www.basejumper.com/videos/Antenna/Invexga_Xtrem_Team_Seguridad_en_Salto_Base_612.html)

Just because I've never seen this way before but also you see a top tuck which works good and almost a little hesitation on the BOC tuck at 6:48.

Still I wouldn't do the same style nor recomment it.
But nice idea which also seems to work...
M.

I left the bridge noticeably head high, so the bridle was certainly more reachable than if I had a good flat launch.


I am always nervous about that tuck, so it was only barely tucked. Wind was very light (3kts) and from my right. I didn't consider it significant enough to switch hands and go handheld left, which I have done in the past to accommodate a 2-way and wind direction. That may have been a mistake. I also never thought of "maintaining bridle tension" as something to consider with the tuck or with velcro. I always thought of it as a technique to make sure it didn't snag anything before I pitched or get wrapped around the bottom corner of the container.

I prefer having a little velcro on the shoulder to mate with the bridle, and may add some. I think the Gargoyle I first jumped had that. The Perigee Pro I have now doesn't really have a good place to tuck the bridle with the riser covers built the way they are. Or maybe it does if you are trying to tuck it very securely, which is the opposite of what I have always done.


That's is exactly the thought I had when I saw the PC, and felt simultaneously very ill and very grateful.

While I fully understand your point. In absolutely any case its going to be at the bottom pin. So if you get comfortable grabbing the bottom of your tuck flap and or bottom pin. You should find bridle.

Yeah, some people say it's not stylish to have a velcro on top of your shoulder, but who cares about fashion.
And after a successfull jump nobody looks shitty anyway ...

So I put it on any of my rigs (there is also a Perigee Pro among them).
Hard velcro part of course on top of the shoulder cover, about at yoke level.
And if I do stowed jumps I just blind it with a strip of conterpart so it doesn't "hurt" anything else.

M.

very good point.

How much canopy time did you have after it finally inflated?

Under 2 seconds.

http://vimeo.com/26274995

Interesting, but I think that the excess bridle left behind in the pouch would be extracted by the airflow in freefall rather than stay in the pouch and get extracted by the pilot-chute itself.

... and so we are back at the beginning ...

I'm telling everyone, spring loaded pilot chutes. it will clear the burble. also the finite 3d size of the Vector pilot chute, for instance, would prevent a knot from creating a total malfunction.

Thanks for posting the video!

I have not seen anyone mention that with the weak pull/early release the pilot is subjecting the pc to a large amount of deflected air from the arm wing. In the video it looks as if the pilot releases before his arm is fully extended thus causing the pc to get a blast of air pushing it into the burble as the arm gets to full extension. Getting the pc into clean air is one of the most important steps to getting a smooth opening sequence. Controlling the loose bridle is another issue. I think that by properly placing the pc into clean air it mitigates the loose bridle problem.

After looking at the photos you posted, I had a thought. Why are wingsuit pilots following the same path, as to get a clean opening sequence, as regular BASE/sky jumpers? Maybe a paradigm shift in our way of thinking needs to occur. Wingsuits create a larger burble than a normal body in freefall, so pitching the pc into this extended burble is just asking for trouble. So I asked myself a few questions... where is the clean air when flying a wingsuit? Where can I place a pc to catch the smoothest airflow? If pilots are going more forward than downward then the extraction happens more behind than above, right? Etc.
After contemplating it I came up with this... a belly mounted or lower pc. Has anyone tried this? One that when released it inflates or begins to inflate in the leg wing area. You have smoother airflow coming across your belly to give the all important initial launch into the airstream and the pc is way ahead of the bridle extraction. Of course there needs to be some way to secure the bridle while in freefall and until the pc inflates and is clearing the jumpers feet.... maybe velcro on the front of the leg wing and a series of pins along the back of the leg wing up to the container. Maybe it can even release your leg wing in the process? I don't know... just brainstorming right now...

Anyone have any thoughts on that??

Wow! Great job saving yourself!!

My thoughts on this entanglement...

I can imagine a pitch that causes the pc to 'roll' off the top of the hand thus subjecting the bridle mass to most of the force when throwing causing the bridle to get ahead of the pc, then as the pc inflates and you fall away the pc and bridle need to swap places and can get entangled. It only takes a millisecond.

Again, just thinking out loud about possible reasons.

Superb job of realizing something was amiss!

Did you stand it up?

Would like to share this photostory, too. It's addressing towards "throwing the pc as your Life depends on" ...

Here are the first 10 pics out of a video I have. Sorry if the quality is not HD.
Seems I can't post more attachements in one reply so you find the rest in a following one.

The story shows a strong move into a pc throw. This created a relative wind and parallel some mass inertia on the pc and bridle so that it changed its intented performance drastically.
This leaded to a 1.5sec delay till the pilot chute startet to work. Also we had been lucky that it didn't result in an entanglement.

I would say that throwing as much as you can is not what someone should focus on on a go and throw. Better just push the pc a little forward, only from your wrist so it gets clean air and does what it's supposed to do and no extra inertia or relative wind is created.
Additionally use a velcro staging on top of your shoulder if you go handheld and pay attention to the wind, meaning strengh and direction. Whenever possible should the wind move the pc and bridle away from you.

M.

pic 11-13

M.

The last photo sequence IMO, to pin the PC funky inflation on a good throw seem to be assumptive, there are many factors, and from this angle i think it is hard to tell what is really going on, BUT I am not even sure the PC really hesitated as much as it took that long in a "no delay" jump, for the PC to reach the and of the bridle and have enough tension to inflate it, i also added a small photo series of a fucking HUCK, and my pins are popped before the pilot chute is even fully inflated. but the PC doesnt inflate till it hits bridle extension. ( this photo series is every 3rd frame as to not bombard with photos )

... just to help you with your doubts: YES it hesitated and on the video you would see that it has been the hard throwmove (it looks like to throw a ball) ,,,

but still feel free to think different

As we do quite some jumps there once in a while we actually have a good reference how it normally looks like.
So this one was different ...
Also I wouldn't post it just for blabla as I think that this thread is quite important compared to others. Actually somehow every BASE jumper should read it :-)

On the other side, we can talk for hours about packing or pc stowing voodoo, but if the pc fails to initiate the opening not only the actor is in deep shit.
So we all should do everything to make the pc inflation happen by purpose. And as it seems, it's an even more fragile moment as we may thought yet...

Thanks for your fotos as they just nail the airflow influence theory in low speed even more.
Of course it always had been there but with all this GoPros we now get a close view of it.

M.

I agree, there looks to have been some PC delay in your photo series, im not disagreeing with that, what i am saying is, it doesnt look like the bridle got taunt and the pilot chute just dragged behind with no action, i am simply saying the PC did its job as it got to bridle extension, leading me to believe that the PC had its own set of issues on inflating, and not the PC toss. Im not trying to argue for the sake of entertainment, i am saying, i dont believe your problem stems from a good toss, if i had to try to pinpoint a problem in a PC unfolding and catching air, i may blame the fold method and or the downside of the PC as it was thrown, such as when i pack my PC, i S-fold the mesh, stack S-fold the bridle on top of the mesh, bring the ZP down around all of that, and have the loose material side of the ZP collection over the bridle S-folds. so, if when tossed, the smooth side of the PC was down with the ZP excess toward the sky i could see the wind blowing around and not inflating the PC till it hit extension. regardless of strength or distance of the toss. I feel a good hard toss will eliminate more problems then a soft limp release.

you definately have a lot more time in the sport and experience than i do, i am just statin my opinion in hopes to have some more discussion so i can understand your thoughts, or more outside discussion from others who may feel why my thoughts do or dont make sense. i am here to learn as much as possible on the ground, learning during a jump can prove hazardous. =D

... and you are doing right, even we both are getting a little to far off the main topic here.

The story behind this particular photostory is even more complex, as this person was doing a FJC at a terminal cliff, never having close instructions about handheld stuff.
We were pretty aware of it afterwards and did all we could to close the gap...

But still keeping pc-bridle-entaglemnets in focus we should say that we shouldn't take pc inflation for granted and we must do it everytime right as we don't have much alternatives.
Statistically entaglement fatalities are not that rare but compared to all jumps ever done we almost seem to be overly concerned now making so much maths about it.

At least it means that we should know our job, pack and train the way we are convinced about it and performe a hundred percent along all known technical plausibel habbits during whatever jump.
No matter if this may start by just untwisting your brakelines on every packjob whilst ending up with a multiway wingssuit proximity flightpattern.

And still BASE will offer so many variabels that it won't be safe for us during all necessary improvisations we might ever face.
Therefore any knowledge (as maybe this whole discussion here) is welcome cause the body easily follows if the mind goes ahead.

But now I'm getting almost to phylosophical ...
Once a good friend of mine said: The main thing what's BASE all about is that you should pull before you hit the ground and don't fuck up.
:-)
M.

I'm a completely BASE noob with 0 jumps and just now looking to GC, but I'm just curious...

Would any configuration of weak magnets (like APEX's bridle routing magnet kit) be able to help with this? I'd think that some quality testing in a wind tunnel playing with different bridle management systems would be quite nice for someone to do.

I reckon this could be a contributing factor. If the bridle & mesh are inside the ZP (i.e. mushroomed) and you give it a good pitch, the bridle can't come into contact with the outside of the zp. The way you stow, you are pitching loose s-folded bridle next to the mesh & zp. I can see how that coupled with a girly pitch could cause an issue.

Good thought.