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As the PC total malfunction created by a knot in the bridle is one of the deadliest mals that can happen, it came to my mind to ask if there is anything we can do preventing it by the construction of the bridle.

Has anyone ever thought/tested a bridle desing that would be less willing to form a loop that can further evolve to a knot when PC goes through it? It could be done by adding a stiffener material inside the bridle, that would like to "straighten" the bridle after being released from PC pouch. (Or just stiff enough to make the bridle less willing to bend to create a loop.) An example of the material could be the yellow teflon cable, or like. Of course the material should also be flexible enough to be packed (inside) with the PC. it would also increase the packing volume of the PC.

Yes, this may be a crazy idea and create a lot more problems than it solves. And the best way to avoid bridle knot would still be a vigorous throw and good PC packing. Opinions?

Vesa

how about surgical tubing inside a double bridal (where the kill line goes on a skydiving pc)

have a CO2 cartridge activate & fill the tube & thus, stiffin it

Now you are making things more complicated. Vesatoro, I think this issue is best handled using proper technique rather than modification of the gear.

Yes, It may well be I'm making things more complicated than needed. One might say same for multis, anti-line-over-toggles, tailgates and other devices that are developed to make base gear safer by still adding complexity to the system. Waiting still for opinions about what problems "stiffer" bridle could create (as everything that makes system more complex, eventually will).

Sounds like a recipe for a hard pull, or some kind of weird kinking that could result in delayed inflation. I just picture way more stuff being crammed into a boc that should be pretty tight as it is.

In 2002 I asked 3 different producers if they could make me a "reserve" option on my new rig! Tod tried to make one, but sent me a ordinary one pin rig with the asnwer it was to complicated!

The system is simple I think!
On your reserve side same place as a skydiving rig, you have an handle with a cable, running to your loop under the flap! Instead of a knot, you have a fixed loop, and a cable running trough. Scenario you have a knot, pilot chute delay, you pull the handle, and your container opens, then you hopefully can shake your pack job out before impact!.

If you are not a low puller, or a wingsuit flyer with alot of energy you dont loos to much hight before you realize you have som trouble, and it might save your life! Simple in my mind.

I have pushed two other producers after that, asked what is going on, and got the answer they was working on it, but that is more than 3 years ago!

I know another finish jumper tried to ask same thing for some time back as well!

Anyone think this should be an option on new rigs?

Yes, I was the finnish jumper asking for the "emergency loop release system". Maybe I like things complicated, but I still think it would at least give a chance when the PC fucks up.

That's a valid argument.

in the meantime... see if you can build a drill for yourself to pull the small loop of bridle that sticks out at the top, above your top pin. by pulling this over your shoulder, you can extract both pins and at the same time extract your canopy with a grip near the apex.

NEVER QUIT!

I am thinking the hardware of the modern RWS reserve pin with RSL could be adapted, if I am understanding your concept correctly.

I have attached a photo of the system.

The white line is the RSL, which is what is attached to the reserve pin. The metal cable is the reserve handle, that once it does it's job of pulling the pin, disconnects from the pin/rsl.

The system works based upon the fact that both the RSL and reserve pin are always pulled from the same direction.

The hazards I can see adapting to a base rig... If the system binds, the PC is in tow with an open/closed container. (duh). Also, the pin has to come out in any direction of bridle pull. (duh).

The question becomes - does the pin stay in the container or stay on the bridle? I think it stays on the bridle.

Interesting discussion...

This is something I have thought about the construction of the Emergency Loop Release System (tm) . The view is from the bottom/pop of the container. A double ended closing loop running through closing flap grommets could be released by the pulling bridle, or by pulling the "red cable" from a handle similar in placement with skydiving reserve handle. The cable would run inside the container flaps in a housing.
Vesa
Sorry for the terrible picture...

I like your idea.


I like your idea better than mine. It seems super easy to make.

Add one more component... In the back of the packtray, put a spring under a flap. As you pull your "reserve handle", the shorter of two lines disconnects the closing loop(s). An inch later as you pull, the flap on the spring releases pushing the canopy at least a foot or two off your back, hopefully enough to get it into the air. The spring could be attached with fabric folded in an accordion, such that when released, it stays on your back like a jack-in-the-box, so the canopy cannot land back in the tray. If it looked like a "cone", the canopy in near dead air would roll to the side. Perhaps the spring is intentionally off center, so it rolls the canopy out to the side instead of up?

Very complicated system... But still an idea.

I have also thought about exactly similar spring system, when I few years ago wrote about it to Blinc, but did not dare to write it here

I'm still wondering if this is a "problem" that needs to be fixed with pin cutaways and stuff like that?

What you guys are talking about was used in skydiving when they first went to reserves on the back instead of the front of the body many years ago. They are called "Last Hope Ropes" or "Jesus Strings." And they caused their fair share of problems.

We all know BASE rigs work so well by virtue of their simplicity. Multis are simpler than deployment bags, Tailgates are simpler than line stows, etc, etc.

However I think (I hope) most of us understand that no matter how simple something is - anything that can happen will (eventually) happen. That's the real risk we understand that non-B.A.S.E. jumpers don't.

I can think of a couple of ways to protect ourselves from pilot chute malfunctions and I've never heard anyone mention them before. Of course I'm not 100% sure about these but this is all good stuff to talk about . . .

The first is the catapult that Mickey Cottle developed for the Reflex skydiving reserve container.

Essentially it’s a second and smaller pilot chute attached to the bridle about four feet below the "main" pilot chute. If the main pilot chute inflates normally it drags the catapult pilot chute along inverted. Under normal conditions this all happens so fast the catapult doesn't really inflate. But if the main pilot chute doesn't inflate you have a chance of the catapult catching air and deploying your canopy. The original version was really designed to deploy the reserve if the bigger reserve pilot chute snagged or wrapped on your body (a Horseshoe mal) but that only worked because of the free bag that all skydiving reserves have. So that aspect wouldn't work for us unless we started using super duper long bridles.

A better (and much simpler) way would be to install small ZP fabric inverted "cups" to the bridle itself. Enough of these would probably get a free packed canopy off your back as long as you got the bridle out.

Of course none of these are any good after you freefall passed "too late junction" but they might have saved Steve Gysting and a few others who had outright pilot chute malfunctions . . .

NickD
BASE 194

From the list:
Oleg
#104
#99
#94
#91
#89
#80
#79
#78
#73
#71
#63
#47

At least all of them had a problem that "ELRS" and training to use it fast enough MIGHT have helped staying alive. Especially for wingsuit base jumping I would like to have that option, as the burble on the back of the flyer adds significant risk for PC malfunction (seen numerous times in skydiving environment).
Vesa

If you have time to evaulate a pilot chute malfunction and reach for a handle, couldnt you just reach back and pull the bridle to pop the pins? Better yet, always give a good hard pitch of the pilot chute, and there will be very little chance of the PC entangling itself. Seems some of those fatalities could have been avoided just by a stronger throw.

Yes, fatalities can very often be avoided by doing everything right. Then there is the random factor, which just happens. But anyway, when the shit hits, I would appreciate an extra "out". With a big winged suit, grapping the bridle might not be so easy...

As long as we're talking about making the system more complicated to get an extra chance in the event of a pc malfunction- if you had a rig with the loop-release, what would your EP be? Considering you're only seconds from impact when you pull on a jump anyway, you have very little time to recognize the problem and act...thinking about it, I believe I'd be pitching with my other hand on the release handle.

As long as we're throwing ideas out, why not consider a pull-out modification where you'd pull the pins manually at the same time as you'd throw the pilot chute...and then maybe add the cups that Nick is suggesting like Rigging Innovations uses on their reserve bridles (might need a wider bridle for that, of course). This might give you an extra chance, as long as you could design it in a way that doesn't present more entanglement risks as the system we're using now...

 
Looking at the photo it seems there was not enough drag on the pc when the "edge" was captured in the knot. It just spilled all the air out of it. I've been thinking for some time about building a set of pc with "gores" and a "panel" shape. It ocures to me that you could build one that was "parabolic", a term from older round canopies. Basicly the mouth narowes below the maximum diamiter of the skirt. In other words the fabric wraps around the bottom of the pc part way. The reserve pilot chute on a wings is a good example of this. That might have created a cup that would have cought air even with the pc towed on it's side. Not the full drag of the PC but it might have been enough to pop the pins.

Lee

hahahaha...

in my earlier days of rope jumping, (single line systems) we had some fairly devastating knot problems.

we (I) tested some stiff jump line rigs, it proved for sure it is a bad idea, and much more usefull to simply be more careful where everything is put. I personaly tried some rigid, sections and some semi-flexible ones.

simple is really really good. the only thing worse than over-engineering is under-engineering.

Precisely, plus-1 on that. Simple is, 'Really Really Good'. The PC, Bridal and the right way/technique to fold PC and bridal and used with the proper way to toss it. Seem to make it the most reliable piece of equipment that you have in BASE jumping next to the Canopy always opening after extraction. 180's and object strikes under a fully inflated canopy are still the top priority on BASE jump killer's. PC entanglement for a total mal. while scary deadly is very low on list of BASE worries. Not saying it's not important but simple mechanics for BASE is best and especially for PC's and Bridals.

I have always wanted to think of something to eliminate the bridal and PC entirely. they seem to cause most if not all of the gear problems.

PS- when you need to give a signal that your about to deploy, the absolute worst thing i think you can do is pull out the pc and hold it in the 'lets have fun with a horseshoe' position for a few seconds before letting go. it is much safer and smarter to reach back and hold the PC for a second before pulling it, it even makes sure you get a good hold of it.

Dur? i think Dur.

Can you elaborate NickDG about the problems of Jesus Strings? I did a search, but I'm more curious about the potential problems that would arise in this BASE application.

Tom A. has done research on this, any thoughts?

In response to the EPs, my guess would be something more like: pitch as normal, wait one second, then reach for and pull the extra handle if you haven't yet felt the canopy come off your back. Assuming you pull at a high enough altitude and therefore have enough time for the emergency handle. I think pulling it too early could create the problem of an out of sequence deployment. If you're already low and you have a PC problem, this probably wouldn't help you anyway.

Like most skydivers and BASE jumpers, I'm not going to jump anything until it is well tested by others, recommended by the person who made my gear, and accepted and used by lots of people.

wonder what the odds will be of messing up and causing an offheading when you reach for the handle.

wonder what the odd are of having your pc tie a knot in your bridle.

wonder what the odds are of being killed by either one.

wonder what the odds are of a random malfunction as a result of further complicating the system.

base jumping is simply risk analysis

remember when your teachers said math could save your life one day? yeah. so far it's saved my life more times than I can count.

Exactly!!
Why reinvent the wheel when proper technique works perfectly well? The mistake on this last incident was to hold the pc (and therefore bridal) in the airstream. Until this accident I had never heard of people doing that to signal opening in BASE.
Waving off takes too long, and extracting the ps is too dodgy... hand on the pc is the signal.

 
"Like most skydivers and BASE jumpers, I'm not going to jump anything until it is well tested by others, recommended by the person who made my gear, and accepted and used by lots of people. "

Pansy. How would we ever make any progress if we all had that attitude. The steps of this staircase are made out of grave stones. Be a man and try to make sure to leave good video behind when you go so we can do a good analesis of the accedent.

Lee

This discussion raises the question of why high drag bridles (similar to skydiving reserves) isn't the norm in a base environment. I don't know whether or not the wider material would be more resistant to tangles, but it may give enough drag to pop the pins if the pc mals. Are there any specific reasons for thin bridles trend in the base environment rather than wide high drag material?

uh, why?

the recent fatality wanted to delay the pc from working. a drag bridle would prevent these intentions. (intentions he should NOT have had.)

it is far simpler to throw the pc as intended!

edited to add:
now if the delay came from a horseshoe malfunction, we have NO freebag. nothing about that system would clear the horseshoe.

What about a pc design with vents like that found on the pheonix fly jacket/pants? They are very small and catch alot of air. With a larger pc to off set the snatch force lost with the vents. There would have to be an exposed vent even with bridle entanglement. ??????

... because if the pc isn't doing its job for whatever reason (say it is knotted in the bridle), having your pins popped by the drag of the bridle is going to make your day better.

this suggestion has nothing to do with horse-shoes... i am simply trying to understand what the specific reasons are for small low drag bridles to be used when wide high drag ones may be a better choice in some situations...

>>The steps of this staircase are made out of grave stones.<<

That's a Nugget . . .

NickD
BASE 194

I think a better way to avoid bridle knots is to stage bridle extension process. Knot cannot form if the PC is higher than the bridle at all times while PC is getting to bridle stretch.

Bridle pocket - an option on Morpheus rigs - retains the bridle on the rig and thus does this staging, but I think any restriction between PC and pin is a bad idea as it serves as a pull force reduction point. (Imagine that bridle snagged on part of your body or container corner. Now you have 3 points holding the bridle: snag, bridle pocket, and pin - which is equivalent to leverage of the 3-ring system).

So maybe a bridle pocket near the attachment loop can do reliable staging? Or maybe just small squares of Velcro on bridle to stage the unfolding of the bridle stack. But that's only for the half that is closer to PC, the other half should not be restricted so PC doesn't fall in the burble on your back.

i still dont think its a good idea. with a 9' bridal on a jump there is nothing to slow the bridal stretch at all (usualy). the reason it is 9' long is to avoid the burble. (dur?, ... dur)
in a wake (burble) there is little, no, or reverse positive airflow to move the pilot chute to bridal stretch. i think anything prohibiting this process is bad.

Im pretty happy with my gear as it is now. People can feel free to test jump their own creations all they want I suppose. For some reason that old video of the golden gate bridge with the guy going double hand held comes to mind. K.I.S.S.

did somebody say horseshoe?

nice picture!

I still contend that the current 9' soft bridal/pc combination works fine when used correctly. complicating the system might help some, but it would add failure modes to the system.

for example...
if the closing loops were double ended and anchored by a cable the jumper can pull, then the same cable would retard the opening of the container! that side flap would NOT want to lie open.

whoa. was that velcro rig?

>>Im pretty happy with my gear as it is now.<<

I said the same thing in 1986 when I had a garage built Velcro container with a Cruiselite in it.

Nobody is suggesting we all start homebrewing our gear again. But there's no harm in talking through ideas.

You never know when someone may have a lightbulb moment . . .

NickD
BASE 194

like thinking its a great idea to hold on to the extracted PC for a second or two at terminal?

no mention of increased snatch force (jerk, aka da/dt)? my calculations, experiences, and arguments I've read have implied that snatch force is very important to overcome the inertia of a relatively heavy canopy and lines, especially on short delays. the only exception I can think of is low freefalls using short bridles and large, pre-inflated pcs.

I think the addition of any sort of "stiffener" in a bridle would make it more likely to form a loop if there was a twist put in the bridle.

Using an extreme example for illustrative purposes only, consider the following:

Take a garden hose and lie it flat. Twist one end and immediately loops start to form. Do the same with a standard bridle and nothing much happens to the rest of the bridle.

IMHO a stiffer bridle flapping at full-stretch behind a jumper is more succeptable to forming loops if there are any twists in the bridle.

g.

>>like thinking its a great idea to hold on to the extracted PC for a second or two at terminal?<<

That's not a light bulb moment. It's something only a relative newbie to parachuting would do. As skydivers we began waving off with our pilot chutes right after Bill Booth invented the throw out in 1975. All was cool and groovy until wind whipped bridles started prematurely opening containers. So I learned that lesson long before I started BASE jumping.

When meeting beginning BASE jumpers these days who only have a couple of hundred skydives I truly do fear for them. I sometimes wish I could hook up a fire wire between our heads and upload what I know into their brains.

Of course, there's a downside for me too, I have to be careful about more things . . .

NickD
BASE 194

Morjesta Vesa,

It's great to hear new ideas for developing the gear, many interesting ideas here! This made me thinking why are we using the bridle that we are using today? So for you manufacturers and old-timers and riggers out there:
1. Why are we not using the wider higher drag type bridle as found on skydive reserves (as also mentioned by Andy)?
2. Why are we not using a thin line as on CRW canopies?

Let's first understand what we have so we don't have to re-invent the wheel (and put the info here:
http://www.basejumper.com/...ear/Bridles_666.html)

"Donk" experienced a complete knot in his bridle on a jump at the Royal Gorge a few years ago. He pitched his PC in a normal manner during a gainer. So we shouldn't assume that knots only form by holding your PC in the wind for a few seconds.

Here's an interesting article on knots.

Another concept I thought about for many years is placing a small handle on my right shoulder that is attached to the bridle between the last pin and the top of the canopy. One could manually pull the pins and manually extract the canopy in the event of a PC malfunction. Under a normal deployment scenario the handle would either be disengaged and left on my shoulder or would travel with the bridle. Or perhaps we are overcomplicating things.....I'm not sure.

http://news.yahoo.com/...enceofknotsunraveled

The only thing I'd prefer to change with my gear (other than my worn out canopy) is the current tail pocket design and the article on knots reinforces my previous beliefs.

Peter the German rocket man had one tailpocket that I thought was great. It had flaps within the tailpocket that separated each figure 8 of lines. There was essentially no easy way for one figure 8 of lines to fall through another figure 8 of lines.

 
Flaps? Loops like an atom? Could you draw it?

Lee

Nicknirto posted pics last year of his baffles www.basejumper.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=2425075;page=2;sb=post_latest_reply;so=ASC;mh=25;]

yes, Lee. I'll post it in the next few days since I'm on a heavy schedule. It's the most significant gear change that should happen as soon as possible IMHO. It's so simply and smart, I just can't believe no one else thought of it.

Not a stiff bridle but it is a stiff PC, sorry about the choppy pics and video I took em with my cell phone.

These shots are of the pc with the mesh removed

I posted the video here
http://www.adrenalinegeeks.com/mov-0017.3gp

i thought of something like that, only with carbon fiber, not metal. i thought it might tangle to easily.

How much does that contraption weigh? Wouldn't extra weight on the PC be a negative affect, especially at low speeds?

it is a little bit heavy not sure the exact weight, the springs are steel so that is the heavy part I am sure there is a lighter way to do it like what Calvin said using carbon fiber or something

it looks too big, bulky, and powerful.

I'd be tempted to try something smaller & lighter. something like a slat from a window blind. a small one. something that will fold up, but will tend toward rigid when released.

heck, even use bungee connected sticks (like tent poles).

but I think ANY mechanism will likely increase the snag potential. use any new device carefully!

 
My God, what a death trap. I'm trying to remember if I was even alive when those things were out lawed.

Lee

Bob Ceylia and I repacked a Russian ejection seat system that had a pilot chute with an opening device kind of like what was pictured. We flipped a coin to see who "had" to sign the card . . .

NickD
BASE 194

Close it is an old military static line reserve throw out pc; ahh. . . . the technology back then. Whom ever wants to jump it send me a pm

my idea was a crossover version, simliar to reserve PCs, only with added carbin fiber spars in the PC sail. this would hold the very large shape of the PC, making a burble hesitation very very hard.

The delrin rods used in many bivy sacks work well. You can shorten them to just the required dimension, and sew them into the topskin tapes to minimize entanglement potential.

I still think there's got to be a better way than that, though.

IM still not for the idea to creat gear that is more complicated. the way that a BASE-rig tend to be safer than a skydive-rig is because of the simplisity of the base-gear.

Wouldnt it be better to find a system just as simple as a normal handle-less PC. But with ideas to prevent uninflated PC:s

A modle like this, is not only heavy for the pilot chute, Its also potentially a danger due to fuck up in the construction that we can't see... fysics and aerodynamics tend to be a bit of a magic-like thing and that is hard to prevent.. its hard to see what could come with this gadgets.

I was thinking that actually spring loaded PCs for terminal jumps might be able to prevent the PC/Bridle knots/entanglements. If you think about it, given that the spring provides a good launch of the PC, there's no chance that the PC or bridle will get knotted, since the bridle will always follow the PC into the air, and will never be able to form a loop and fly above the PC.

Of course this won't work for subterminal deployments because of the weight of the spring, but on subterminal jumps the standard system works well already. I'm only proposing this for terminal jumps.

Keen to hear your thoughts.

 Using a spring loaded pilot chute would have exactly the opposite effect of what your post suggests. Skydiving students don't use spring loaded pilot chutes for main deployments anymore for a good reason. To name a few: True pilot chute hesitations, much higher entanglement possibilities, pilot chute falling over the front of the parachute after deployment.

 

Sounds like a Death Sandwich to me....but hey...what do I know.

Why change a winning formula?

I don't particularly like the idea of a big spring in my PC and pack job.

Start a poll and see how many people would jump with a spring loaded PC

That's because it is.

....
andubkov

I'm aware of what happens using a short bridle with any pilot chute, especially a heavy unpredictable spring loaded pilot chute that you can't physically place outside a burble. It was a happy day when the DZO was finally convinced to use hand deploy on student gear.

The dropzone.com discussion has nothing to do with base. Using your first post on basejumper.com to try and introduce springs into base jumping sounds very much like trolling. This thread was 3 years old and the dz.com post is 5 years old.

Here's an Idea. Rather than try to convince you why it's a bad idea to redesign our equipment and procedures to utilize an antiquated design, you come up with a good reason to change a very simple design, to make it less reliable, more complicated, and less user friendly.

Thanks.

 

Thanks for your response. I devised a reply but it stated the same thing as treejumps post.

Using a light weight low profile handle (or no handle at all or an internal handle) is important. Confining the bridle properly inside the pilot chute and tossing it quickly without holding it outside of the pouch will almost completely eliminate the possibility of a bridle knot.

Hope that helps.

it might be old, but it's not outdated, (ok, it's outdated too..) but, the military still has plenty of t-10 reserves with this style of PC getting jumped. sadly the faa and military can't advance at the same pace as the rest of the world. An exception were some navy t-10 reserves with no PC, jumpers were expected to throw the canopy into the wind (like a paraglider reserve, but not bagged at that point)