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Supposed to reduce dynamic shock and reduce the chances of premature break cord breakage.
But isn't that a little overkill? I mean, the whole shock absorber part sits inside the container

I think it makes common sense. The more you can reduce the dynamics of the weight, the more control you have. Which would lead to more accurate breakage of the cord.

It makes sense when you know you're doing a SL jump before you pack and rig your kit.
Probably not so much on those days after you have climbed to the top and just didn't feel
like free falling for what ever reason. That's when break cord (and a good method of hooking it up)
comes in handy.

The reason this makes sense is because it reduces dynamic loading of the break cord. If I were to build a shock absorbing setup it would be not on the bridle but on the lanyard I use between the bridle and the object. I would also back up the bungee with a solid length of lanyard in case the bungee failed. Although the bungee idea makes sense to help prevent premature break cord breakage I wont use it because it creates more complication which is a good thing to avoid. I use a backup break cord an inch or so longer than my primary. Of course any system could fail and you could die.

how about just using a piece of rope (or something of the sort) that gives a little...aka shock absorber..to tie off to...

Click Here!

This video is the reason why I posted in the first place

This is interesting, but what's the real pressure required to open pins and extract a canopy to line stretch? The five lbs weight drop might not be a good analog.

That's the whole thing, an s-folded canopy is not the same as a chunk of metal, since the s-folds are extracted gradually. I bet the force is lower than 50 pounds most of the time.
Still, attaching the SL to the middle of the bridle (and it being 160 lb break force) probably solves everything

On a side note: I recently heard of an incident where a mis-rigged sl setup left a jumper hanging from the object.

Was it a CWY setup that was attached to the bridle directly & got snagged on something? I used to have a S/L set up that was one piece of line with loops on either end with a short line finger trapped & coming out the middle with a loop at the end of that. It attached to the bridle with break cord, so if a snag were to occur, it would release from the bridle.

I have since misplaced it & want to buy a new one, so if anyone knows where I could obtain one, I would appreciate it.

Can you maybe provide more details on this? How was it rigged to be hung up on an object?

+1, would love to hear the details on this.

I believe that the setup you describe is the safest one yet.
Fingertrapping dacron is pretty easy, your rigger can make one in 15 minutes. You can also make one yourself, it's not that hard.

RE: SL failure: Unfortunately I don't know anything more about it.
I now actually have big doubts about the truthfulness of the info. So don't take it as a fact.

I have quite a big doubt as well on the thruthfullness since it is very difficult for me to think of an setup based on which you would actually be left hanging on the object. This topic was also touched on an earlier thread here : http://www.basejumper.com/...post=2946900#2946900 where TomA was sharing some insights on the weak points of the static line setup.

Maybe usefull to understand the forces on a bridle during freefall extraction compared to staticlinejumps, look here:
http://www.watchthybridle.com/...t-chute-pull-forces/

Little off-topic, but maybe good to know...

The shock absorber idea is great, however it further complicates the system (duh)...

Most of the time when we are doing a SL we are doing it because we are at an altitude that does not allow freefall - in which case the extra couple of feet the shock absorber adds to the bridle may eat the ever critical altitude - yet the method of attaching the SL half way down the bridle reduces both the risk of a premmie and the distance to line stretch.

not to mention that I rally get paranoid of messing with the bridle (aka the life line). Remember the black rubber bands that were used to stow the multi ? Didn't work out to well on a large sample :(

Hey Paul, I doubt the bungee would add any extra length to the bridle. I would assume that it would still be 9ft once it's under full load, or fully stretched. Also it looks like it only stretches less than a ft, and if that's gonna make a real difference you got bigger balls than me! However, I agree that it adds complexity to the system, and extra bulk inside the container. I would just tie the bridle in half, but I'm a pussy and a firm believer in the KISS theory

I bought a new 2 pin bridle from Morpheus
and turned my old one into a Static-Line
only bridle by sewing a loop in the middle.

Works great, very simple, shortens the fall
til loading by 4ish feet. I attach the bridle
to the object with 2 pieces of break-cord,
usually one loop and one longer strand.

I also attach a long, thin rubber band
(the kind you'd steal from the office
supply cabinet) to the object and then
put a little bight of the *PC's apex in it.

*Zach aka Hikeat mentioned it, I tried it,
really liked it, the idea being: don't have
the PC blowing out in front of you so less
chance of snagging the PC on the object
or your boot, and if for some freak reason
both pieces of break-cord give way too soon
your PC is in perfect orientation to inflate.

Of course this static-line bridle only works
if you know in advance you plan to do one.

For static line jumps using standard bridles
I have done the knot in the middle as well
as used the loop at the end of the bridle.

Only time I have had premature breakage
was when using only one loop attached
directly to rusty, jagged metal.

Hey guys I was reading about all of your concerns and I have been jumping a prototype of the Apex shock absorbing bridle for a while now. Let me explain how it came to be. We had data that a 300+ square foot canopy tied to the end of the bridle has broken the 80lbs cord prematurely. Someone in my area that has hundreds of old school SL jumps and has NEVER even jumped a PC took the time to share his SL experiences with me. Back in the day they were doing SL with Velcro rigs by removing the bridle altogether and attaching the break cord directly to the shrivel flap. That's also were the rule of thumb comes from to have the SL be 3 feet past the edge of the object. You still freefall all the way to line stretch while gaining separation from the object. At that distance fallen the break cord is obviously VERY reliable, which is why the guy is still around. Personally I would use 2 different size loops of break cord as shown in the Apex video, but not for strength, for redundancy. What if the first piece of cord had a nick or a defect? As Todd was saying in the video that doesn't add any strength to the system. His way of attaching the PC with a separate piece of cord has the disadvantage that it tends to make the canopy jellyfish a bit as it breaks. But even in that configuration the second piece does not add any strength. If the piece attached to the shorter tie off point on the bridle fails, the second one will fail as well.
My preferred method is to tie off the PC with the same cord that I tie the half way point. It now is controlled until line stretch at which time you are far enough away from it to cause any issues. I do still do a tight and a loose loop for redundancy, but they both go through the half way point on the bridle AND the end loop with the PC attached. It seems to eliminate that second jolt to the canopy as it is trying to inflate.
But let's get back to the shock absorber. I went to Twin Falls to test the first versions of it and using a 27ft bridle on a FLiK242 the video shows that the canopy didn't even get the first fold out before the cord broke. With the shock absorber I almost achieved line stretch. At that point I wouldn't even have needed a PC to get a canopy. I have since then had that bridle on my container for ALL my jumps. Jimmy from Apex Moab has been jumping it as well and he is very excited about the system. The protective sheath covering the device provides no snag point and does not need to be stowed inside the container. I just lay it in there neatly and you just forget it's there. The system is fully redundant so if the bungees fails you still have a bridle. The added length inside the container is about 6 inches, which I find acceptable. If you find yourself in the situation where you need to tie off you just do it and the system does its job. I am sure on terminal jumps it gets quite a bit of a workout as well but reducing the dynamic forces would if anything dampen PC oscillations.
Please share your thoughts as I am very interested. We are trying to make this a simple, fail safe system that will contribute to safety in BASE.

I'm a little confused by your statement "does not need to be stowed inside the container." Where does the bungee part of the bridle go when the rig is packed. Does the bungee section pack into, or outside of the rig?

Thanks for explaining the bungee bridle. Will it be available soon? I have not seen it listed on the APEX website and I would be interested to try it first hand. Prior to your post, I was wondering if another benefit of the bungee bridle would be to reduce PC oscillation in sub-terminal and terminal jumps. Do you plan on doing any more testing to see if oscillation is reduced?

I understand that some jumpers like the KISS (keep it simple stupid) system when it comes gear, and I do too, but the bungee bridle doesn't look very complicated or add all that much complexity to the system. If it makes for a safer static line BASE jump, and or reduce oscillation then I'm all for it.

Just wondering if the bungee on terminal jumps would tend to 'bounce' while extracting the canopy? Going to full stretch then rebounding back, then to full stretch again etc.

Thanks for the added info on the SL.

There are some great load tests for static lines done worth reviewing
http://www.blincmagazine.com/...tatic_Line_Evolution

I don't think it will bounce (god I hate that word). But I do think that the overall length of the bridle will change depending on the forces exerted by the pc
for example, the bridle will be short as the canopy is extracted and it will be longer when the canopy is at full line stretch.

I also think that this MAY reduce canopy distortion during extraction, since the PC force spikes are dampened, which is a good thing

It just sits on your bridle between the canopy and the first pin. So when the rig is packed it's inside the container just laying there. I usually lay it straight up and down.

The bouncing of the PC at terminal is a good point. I haven't seen any evidence of that so far. I think it will definitely dampen the PC's first "hit" and probably also reduce center cell strip. The best way to gather data about that is to have people jump it and see what happens. I haven't felt any adverse effects to my regular jumps so far.

here is a deployment video of a terminal jump:

http://www.youtube.com/...amp;feature=youtu.be

is your bridle now shorter....only getting to the full 9 ft at full extension?