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Considering the role of line stowing in deployment headings-

Much of the video of slider off openings I have seen shows that the canopy comes out of the container predestined to open off-heading before full line stretch. When the packjob is already pointing 90 left (for instance) before it's begun to inflate, could this be a factor of improper line stowage?

And for slider up jumps- The other day I had 540 degrees of line twists on a terminal jump. I noticed that my tailpocket velcro had opened about 30% of the bottom edge (more than ever before) indicating a partial line dump... or something... obviously this could have had a lot to do with the line twists...

I'm searching for answers form some of the more experienced jumpers out there- how much does line stow technique have to do with headings, and are there any secrets out there for stowing lines incredibly well?

Thanks.

Lines freestowed in a tailpocket are very unlikely to affect opening heading. There really isn't that much tension on the lines as you're falling away, pulling the packjob to linestretch. There's not much force exerted on the canopy by the deploying lines so it's hard to imagine the lines inducing a turn into the packjob.

If the video is showing a rotated packjob before it gets to linestretch you can pretty much eliminate uneven risers (caused by bad body position). Your likely culprit is either PC oscillation, wind pulling the PC off to one side, or part of the container inducing a turn into the packjob as it leaves the packtray (this one can be caused by packing, tight container, poor body position, or high forward speed).

The packjob is really vulnerable to any inputs between the time it leaves the container and the time it gets to linestretch. An oscillating PC can easily mess up your heading.

There are no secrets to stowing lines neatly, just take your time, make sure the bights are seperate, and don't mash things up when you close the tailpocket.

Have you considered putting flaps in the tailpocket, to separate the loops of line?

I actually have one half built on my sewing table... hehe

What about rubber bands INSIDE the tail pocket? I've seen few of these. Any cons?

Most everyone abandoned that 5 or more years ago. The problem is that as the rubber bands "racetrack" and pop open, they wiggle the canopy as it moves to line stretch. During the move to line stretch, the canopy is very vulnerable, since it's not under tension.

Even the slight impetus from the rubber bands going appears to create noticeable twisting as the bundle moves to line stretch. I'd recommend against using the old rubber band stows.

Line dump from a tailpocket can cause a certain of malfunction, i.e., line entanglement potentially with premature slider descent.

People have used rubber band stows with success in cases where "pony tail" rubber bands (very thin breakable rubber bands) are used. The tension created by such a system is generally not enough to torque the canopy during line stretch. I have seen it used very successfully by a few jumpers.

If you canopy is turning before completion of line stretch, consider the following options:
1) rotating pilot chute. Consider centering the bridle attachment on the pilot chute or purchasing a apex-vented pilot chute.
2) the canopy is catching some part of the container during lift off.
3) the stabilizers are too exposed and should be 45 degree folded.

Do you think it's necessary to attach the rubber bands to the tail pocket? What if you just used them to gather the lines, but left them hanging free?

pgpilot....
"I noticed that my tailpocket velcro had opened about 30% of the bottom edge (more than ever before) indicating a partial line dump... or something..."
........................................

I have always been under the impression that worn out Velcro on the
Tail pocket promotes line dump and possible line twists ????
That is the rule that I was taught and pretty much live by.

How is the condition of your Velcro on your tail pocket ?

my canopy has about 50 jumps on it, so the velcro is in decent condition... I was actually surpised by how quickly it wore out, but it's not too bad. Dagger 222 in a warlock, just fyi.

thanks for the good info.

Where can I buy the tailpocket with the flaps? (if it can be bought)

And who- although I realize this is a nearly impossible question to answer- makes the best vented pc? I'm ready for a couple new ones anyways.

As far as I know, no one is offering them stock. You'll have to have one constructed, but it's really not hard.And who- although I realize this is a nearly impossible question to answer- makes the best vented pc?
My opinion is that Asylum makes the best vented PC's. I like the "overhung" shape of the ZP, which I feel makes the PC profile more stable.

Rigging solutions will have vented and non-vented pc's available at their bridge day booth. Gus will also have a sewing machine on-site for repairs and such. I'm sure if someone has an idea for the tailpocket flaps, he can make it happen.

Ganja

Are you using a tailpocket with the anti-line dump flap technology that is standard on both BR and CR canopies (originally developed by Sandy Reid of Rigging Innovations on reserve freebags)? If not, your lines will flow through your velcro causing unnecessary excessive wear on your lines and velcro.

Tom wrote:

Do you think it's necessary to attach the rubber bands to the tail pocket? What if you just used them to gather the lines, but left them hanging free?
I see no advantage to using rubber bands to gather lines but leave them hanging free. The point of the tailpocket stows is to prevent sudden line dump. The locking stow at the base of the canopy should prevent premature slider descent that can possibly result in an entanglement. However, no system is perfect and minimal redundancies can be crucial to a lifesaving system such as a parachute. I believe the primary reason people have eschewed or avoided using rubber bands was simply because of effort and the attention required to assemble a system correctly. However, as you know, the rule in parachutes is staging, in order to prevent the many unknown things that can possibly occur. We currently have a system that is pretty good so long as the anti-line dump flap velcro is in good shape and final locking stow is secure, but not too secure. The flap separators seem like an ideal way to go, if manufactured very carefully. I'm rambling...

pgpilot....
"The other day I had 540 degrees of line twists on a terminal jump."
..............................................................

One more thing that I was rolling around in my head today.
about your, Line Twists.

Just a thought. If you are possibly using a Pilot Chute that is a
little to large for that speed of delay in Free Fall.

You could be having, Center Cell Strip.
Known for, Off heading and line twist.

I was using a 32" ZP large hole mesh, 15sec delay. I am leaning towards pilot chute oscillation due to the fact that I am now 5 for 5 with violent off-heading openings with this PC. My friends and I have dubbed it the 'mad oscillator' actually, or the pc of death. It's done, I'm tossing it. It could just as easily be me, my bad body position or packing or whatever, but it's in my head now that this pc is not hooking me up, so I have to toss it. The blown velcro on my tailpocket threw me off though, and convinced me to ask here. I will seek out the flap system.

treejumps: thanks a bunch for the offer, but I can't send my rig to MD now. I'm on my way to France.

I'm new to this forum but I am impressed- it works the way a forum should- nice folks sharing good info. thanks for the help.

My opinion is that Asylum builds the best pilot chutes, vented or standard. The quality of work is impeccable and there are lots of subtle things that make the pilot chute more burly. If I had you here I could show you what I'm talking about since it's much easier than writing and I'm actually pretty busy right now.

If you feel like it, take my word for it and order some Asylum PC's. You won't we disappointed, in fact, you'll be extremely satisfied.

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Disclaimer: I am not an Asylum sponsored jumper. Asylum doesn't give me free gear, discounts, or other perks. The only affiliation I have with Asylum is my complete satisfaction in their gear and their excellent customer service.

Sponsored... hehe... who'd be silly enough to sponsor me anyway?
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ill sponsor you a beer

As vented pc´s i also go for Asylum,however if it needs to be BIG and unvented ill take a BR as it is right now.

Take my oppinion by a grain of salt as i didnt freefalled other pc´s than from thouse manufactores.