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Tilley Fold - Symmetric vs Asymmetric
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John_Scher

Mar 16, 2020, 12:19 PM
Post #1 of 22 (2614 views)
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Tilley Fold - Symmetric vs Asymmetric Can't Post

 

In 2012 there was a thread with mentions of the Asymmetric Tilley Fold and since then one or two mentions about it from HJ33 and perhaps a few others but very little.

I’ve always used the Jesse Hall method which is Symmetric but am really interested in reducing the bulk on my pack jobs but still retain the benefits of the Tilley Fold i.e. promoting Nose First inflation thru inhibiting the tail from inflating and inverting and thus significantly reducing the chance of line overs.

With all that said I can’t find a description or diagram of the Asymmetric folds other than someone saying it’s folded in thirds rather than quarters. I can of course take a guess, trial and error but would prefer and appreciate if someone can better describe the Asymmetric bit or better still post a diagram or video

(This post was edited by John_Scher on Apr 3, 2020, 8:44 AM)

BodeyM

Mar 16, 2020, 8:54 PM
Post #2 of 22 (2569 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

Is this helpful or is it the thread you're already talking about?

http://www.basejumper.com/...post=2991446#2991446

John_Scher

Mar 17, 2020, 11:27 AM
Post #3 of 22 (2490 views)
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Re: [BodeyM] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

 
Bodey, I haven't seen that thread before and it is helpful or at least it should be. I appreciate your effort but it just seems I'm too thick to actually visualise what is meant by...

the accordion folds on each side go on top of the tail in "interlaced" manner, e.g. left-right, left-right, left-right - full width, without first folding them in half

...Three lots of left-right left-right left-right full width??

BodeyM

Mar 17, 2020, 11:42 AM
Post #4 of 22 (2484 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

I haven't played with it but I think what he's saying is the three main folded stacks of fabric on each side of your packjob, once you've cleaned up your tail, alternate folding those across the pack job left, then right all the way down. Does that make sense?

John_Scher

Mar 17, 2020, 12:10 PM
Post #5 of 22 (2481 views)
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Re: [BodeyM] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

 

...yes I'm understanding what you're describing.

Interlacing is yet another variation.

I wonder what Tom A and HJumper33 think of this interlace method

I must give it a try and see how it comes out.

Why don't you use it?

BodeyM

Mar 17, 2020, 1:03 PM
Post #6 of 22 (2475 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

i don't jump very much and test jumping something i read on the internet is scary haha

epibase

Mar 17, 2020, 5:25 PM
Post #7 of 22 (2449 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

Ive been doing the asymmetrical tilley fold for 400+ jumps.
Slider up and slider off.
Once the tail is neat and tailpocket pulled down, i fold the entire left side over the middle, then the entire right side on top of that.. ive never tried with alternating method.
I still have on headings 90% of the time, and have never had more than a 90 in the other 10%..

hjumper33
Moderator
Mar 20, 2020, 6:08 AM
Post #8 of 22 (2281 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

Ill take a picture the next time I do a pack job, but yes its just as described by Jay above. I do the right fold first and then the left, but I dont think it matters at all. I use a single clamp to hold the folds together, but the folds themselves are pretty much in line with the tail pocket edges. Its funny that you mention Jesse because he is the one who first showed me the asymmetric fold many years ago as well.

AntoineLaporte

Mar 25, 2020, 3:38 AM
Post #9 of 22 (2089 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

I've done both.
Now only doing the All_one_side/All_the_other_side.
I do not think that the little asymetric thing is changing something significant in the chaos that is a parachute getting out of the container, but it does not look as nice as the symetrical technic, and it is good for beginner to have something looking nice, it makes people feel more confident in the packjob and it helps for focusing on the other parts of the jumps.
I just chose this method first for slider down thinking that less folding is easier to unfold, and so, better for faster openings (this is also very probably more for my own confidence than it really does something).

hjumper33
Moderator
Mar 29, 2020, 9:27 PM
Post #10 of 22 (1880 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

Antoine my thinking is about the same. I carefully dress the nose as center first inflation is pretty darn important for heading, but the tail just kind of does it’s own thing regardless of how it’s folding during that inflation. I do fold a 45 into each side of the tail, and then under before I do the large fold.


(This post was edited by hjumper33 on Mar 29, 2020, 9:31 PM)
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TomAiello

Apr 2, 2020, 12:12 PM
Post #11 of 22 (1735 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

We ran asymmetric Tilley folds on all the student gear for about a year, and we found a noticeably higher off heading rate.

On reviewing the (top) video of the deployments, it appeared to me that the canopy had a higher chance of turning after extraction, as it travelled to line stretch.

My hypothesis is that the weight of the canopy hangs asymmetrically below the bridle during extraction, because one side is unfolding earlier than the other, creating different "moment arms" (and probably different air resistance, but I don't think that would be enough to explain the heading differences we observed). Because the weight of the extracting canopy was hanging differently on the two sides of the extraction point (the bridle attachment) it seemed to be rotating the entire bundle toward the "top" side (the one that was placed on top of the other in the assymetric folding).

Everyone can make their own decisions, but after reviewing the approximately 500 openings done with an asymmetric fold, we discontinued using it and went back to a symmetric fold on our student gear.

If you want I can dig out some of the video and email it to you.

BodeyM

Apr 2, 2020, 5:34 PM
Post #12 of 22 (1716 views)
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Re: [TomAiello] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

Do you have any info like that on the 45 degree bottom corner folds?

wasatchrider

Apr 3, 2020, 8:31 AM
Post #13 of 22 (1682 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

John_Scher wrote:

In 2012 there was a thread with mentions of the Asymmetric Tilley Fold and since then one or two mentions about it from HJ33 and perhaps a few others but very little.

I’ve always used the Jessie Hall method which is Symmetric but am really interested in reducing the bulk on my pack jobs but still retain the benefits of the Tilley Fold i.e. promoting Nose First inflation thru inhibiting the tail from inflating and inverting and thus significantly reducing the chance of line overs.

With all that said I can’t find a description or diagram of the Asymmetric folds other than someone saying it’s folded in thirds rather than quarters. I can of course take a guess, trial and error but would prefer and appreciate if someone can better describe the Asymmetric bit or better still post a diagram or video

Jesse used a symmetric for the video but usually folds asymmetric. I have hundreds on bock and found no difference in heading. I fold symmetric now just because I use a top through loop

John_Scher

Apr 3, 2020, 8:40 AM
Post #14 of 22 (1681 views)
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Re: [wasatchrider] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

 

Does Jesse still jump?

Do you know his email adress?

I wonder what Marty has to say. I'll ask him.

(This post was edited by John_Scher on Apr 3, 2020, 8:43 AM)

TomAiello

Apr 3, 2020, 12:06 PM
Post #15 of 22 (1664 views)
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Re: [BodeyM] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

BodeyM wrote:
Do you have any info like that on the 45 degree bottom corner folds?

In my opinion they make no difference at all.

I haven't run them on the student rigs for a year to see if there was any difference though.

I formed my opinion on the 45's (and basically all micro-reefing) doing a series of drop tests with a friend off an apartment balcony (in the French Quarter--it was a great trip that generated a lot of good memories) a long time ago. At the time, I was an advocate (and user) of a bunch of micro-reefing (including 45s). He thought they made no difference and would just make big simple folds to narrow the pack tray.

To test we dropped (with video) about 20 pack jobs from a balcony that was just higher than line stretch. We held the bridle (like a PCA, basically) and then dropped the container. We went back and forth with camera angles trying to get the full drop in frame as well as a good shot of the canopy.

What we basically found was that by the time the container hit line stretch (in mid air below us), all of the careful micro reefing in my pack job had already fallen out. Basically, the micro reefing was encountering very little airflow during inflation, because there was never any line tension while the micro reefing was still present in the pack job.

I really didn't believe him that it didn't make a difference. But I was at least open minded enough that I started jumping my two main rigs back to back, micro-reefing one in my normal fashion and simply folding the other, the way he did. The canopies were different (Mojo 260 and FOX 265, in a Vision and Prism, respectively) so I alternated which one got the micro-reefing, so they each did 50 jumps each way.

After about 200 jumps (a hundred each way, 50 per canopy), I had not observed any difference in outcomes. I was recording heading on the jumps to compare on a spreadsheet (which showed no measurable difference after a hundred jumps each way), but I didn't have outside video, and many of the jumps were done at night, so I don't have any direct opening video to look at. Maybe I should re-visit the issue at some point, but I haven't gotten around to it, and it's pretty low on my personal priority list.

wasatchrider

Apr 3, 2020, 1:34 PM
Post #16 of 22 (1656 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

John_Scher wrote:

Does Jesse still jump?

Do you know his email adress?

I wonder what Marty has to say. I'll ask him.

He still jumps I would just message him on facebook messenger

jjmacc

Apr 4, 2020, 2:26 AM
Post #17 of 22 (1622 views)
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Re: [wasatchrider] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

This thread is something I'm really interested in. I've got a Flik2 290, and its a wide canopy, too wide to just fold it and have it be symmetrical at the half way point.

When I started, I would fold the first side, then roll the edge back to centre, then repeat on the other side.

Lately ive been doing a 'mini fold' and folding each side almost in half, and then over again to meet in the middle.

Both these methods work fine, but Im quite keen to give the asymmetrical way a go.

Having spoke to my friend about this last night, he tells me he's been packing his blackjack asymmetrical for years because of the same reasons, and his OSPs the normal one fold to half way method.

Just wondering for those of you with larger canopies, especially Fliks, if you're not doing the asymmetrical way, how are you guys doing it?

RGrove

Apr 4, 2020, 7:36 AM
Post #18 of 22 (1607 views)
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Re: [jjmacc] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

I jump a Flik 2 290 as well, fold asymmetric, and there is no difference at all. It fits in there much nicer without adding a bunch of extra folds.

TomAiello

Apr 6, 2020, 12:19 PM
Post #19 of 22 (1484 views)
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Re: [jjmacc] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

jjmacc wrote:
Just wondering for those of you with larger canopies, especially Fliks, if you're not doing the asymmetrical way, how are you guys doing it?

I usually tri-fold (like a tri fold wallet) so that I'm making two folds in each side to reach the center.

I have a friend who just rolls the sides up, and when I'm in a hurry I do that.

Honestly, I haven't seen any difference in outcomes with one big fold, two little folds, twenty five micro-folds, rolling, or whatever. As long as it's symmetric between the sides it seems to open more or less the same.

jjmacc

Apr 7, 2020, 9:10 AM
Post #20 of 22 (1388 views)
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Re: [TomAiello] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

Thats sounds like what im doing now tom, think I'll stick to it for now.

Definitely going to pull the rig out and play with a few methods now I have all this time on my hands though and try to neaten it up a bit, I find those small folds before the main folds are different every time, and sometimes 'seem' a bit uneven, maybe the asymmetric way will work better for me, we shall see!

John_Scher

Apr 7, 2020, 9:13 AM
Post #21 of 22 (1386 views)
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Re: [John_Scher] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

John_Scher wrote:

Does Jesse still jump?

Do you know his email adress?

I wonder what Marty has to say. I'll ask him.

I asked Jesse what method he uses and he commented just now…

"The same Symmetrical one from the video"

(This post was edited by John_Scher on Apr 7, 2020, 3:21 PM)

John_Scher

Apr 7, 2020, 3:44 PM
Post #22 of 22 (1344 views)
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Re: [wasatchrider] Tilley Fold - Symmetric vs Asymmetric [In reply to] Can't Post

wasatchrider wrote:
John_Scher wrote:

Does Jesse still jump?

Do you know his email adress?

I wonder what Marty has to say. I'll ask him.

He still jumps I would just message him on facebook messenger

Marty responded which I have summarised thus...

There are subtle arguments for both symmetric and asymmetric. An extraction after a one-second delay will be different from sub-terminal and terminal canopy extractions, relating to relative wind exposure and effect of a slider.

Symmetric is even and balanced and is seemingly preferred as it presents a balanced and typically more evenly distributed package, however deployments are chaotic

I use, and local jumpers use both versions.


(This post was edited by John_Scher on Apr 7, 2020, 3:48 PM)


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