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I've tried a lot of the pack jobs out there at one point or another. And I have had a lot of good openings, and some that were a little bit on the spicy side as well. In all of my pack jobs I have kind have relied on a handful of rules or guidelines if you will. They are in no particular order:

• Symmetry
• Line Tension
• Lines in the middle, fabric to the outside
• "Aiming" the pack job so it sits straight in the container
• A neat flaking/ dressing of the nose

I have never worried much about showing people that I'm a fast packer and therefore cool, but at the same time its rare that I brake out the starch, iron, and microscope for a pack job... unless I'm bored and have nothing better to do.

The first three bullets that I listed above have always been a kind of boring, common sense part of the pack job, but for whatever reason I have always harped on the last two thinking that it would really make a difference. As far as the dressing of the nose goes for slider down jumps I have folded it back on itself like Jesse Hall teaches in his video, I've rolled it back and stuffed in pockets made by the center cell like Tom Aiello shows in his video, and I've folded it in a simple fold like the one Apex recommends in their old video, and the way Consolidated Rigging shows in their Ram Air Parachute manual. No matter which flavor of the week I'm doing in my pack job I'm always making the nose neat, and constantly seeking out information to make my pack jobs better.

Today I got a new canopy in the mail, and when I after screwing around with it and making sure it was in good shape I put it away and broke out the laptop and reviewed Consolidated Rigging's Manual and noticed the following in bold print:

" In a slider removed deployment, the canopy’s lower surface will spread (inflate) before any air enters the nose. For this reason, and others, nose treatment will have little effect on heading reliability or opening speed when deploying without a slider."

I also noticed that in the manual there was no mention of the forty-five degree fold of the main flaked panels of canopy at the bottom of the pack job that is common with Apex's pack job Jesse Hall's pack job and any other pack job that uses a "Tilley" fold.

The things I wonder after noticing these things are:

• Is the way and precision with which you dress the nose of the canopy really immaterial in a slider down environment?
• Is it mainly symmetry of the pack job, and other outside influences like body position, winds, and pc oscillation that affect heading performance?
• If bottom skin inflation occurs before any air enters the nose, should anyone do the forty-five degree fold or roll at the bottom of the flaked panels of canopy? What would be reasons for doing so, or not doing so?

After thinking about the way that a base canopy opens, and seeing footage and still photos of many deployments, I think it's actually kind of amazing that any base canopy opens on heading any percent of the time.

Do any of you have any thoughts on this stuff? That is other than the old sayings of none of it matters just stuff it in the container and go jump. I'm certainly don't think that the wave length of light colors coming off your canopy will cause an off heading, or any of that garbage. But, I'm interested to know if anyone has any firm opinions based off of their experience that cause them to think one way or another, and of course why.

Sorry for writing a book of a post. Thanks for taking the time to read it if you made it this far.

FALSE. black bear.


I have found that the most important thing you can do on slider down is reverse-engineering the extraction, then everything else.

What I mean by this is placing and sometimes slightly pre-stripping the center cell so it yanks everything else out evenly and without twisting the packjob. Note that this can be different with different final folds and intended deployment pitch angles. (On a long delay jump generally I am farther head down in a track, on slider off it is variable, so I use a flat and level minded extraction algorithm)

Further, on slider down where the extraction and initial inflation is poorly staged it is very important where the nose/center cell is and where it wants to pull the rest of the packjob. If your nose is burried in a bunch of nylon poop and the stabilizer inflates first, your opening could go anywhere. If the nose/center inflates first your packjob would mst likely follow wherever that is pointed.

Of course, the REAL most important thing in slider down heading performance is body position at the time of extraction in reference to the gravity vector and relative wind vector.

I have no expert knowledge on this, but it makes since to me that if the center cell is unobstructed, unfolded, being separated with opposite pull forces from lines and bridle, and facing the direction of flight (down and forward) then why wouldn't it start to inflate first when the nose is shotgunned? The time difference doesn't look like much in video, but it seems pretty obvious to me.

BTW, I'll probably die soon.

I agree with both of you, I've always thought that the dressing of the nose was really important. Of course I also think nothing in a great pack job can fix crappy body position, or some of the other external factors that we know about.

I guess what I'm curious about is the idea of bottom skin vs nose on slider down deployments as far as which one catches air the most and first.

I'm just having a hard time believing what I saw in Consolidated Rigging's manual, saying that the dressing of a nose slider down doesn't affect heading performance.

And Calvin has proof!

Here is a pic of a non-vented canopy, slider off. You can see the two end cells (6 and 7)and the center cell (1)pressurizing from the nose back to about the B lines, maybe into the C lines. There is not much inflation of the bottom skin. And not really any pressurization of cells 2,4,3, and 5.

I wuz learnt that the center cell nose should be dressed so that 1/3 of the air goes into one side of the center cell and another third goes into the other side, and the other 1/3 hits the bottom skin of the center cell. AND THAT is what/should establish heading.

The center cell on that canopy is the first yellow cell touching the grey cell. You can see the exaggerated center cell pre-stripping, and the consolidation folds are asymmetric, one side on top of the other.

Add a tailgate to the recipe.
Take care,
space

This one's pretty neat too: http://www.basejumper.com/...SPAGHETTI__2052.html

Nose seems to have no appreciable influence on opening heading in my experience for slider down.

With the tailgate and a non-spiraling pilot chute, we now have the best openings I have ever seen. The tailgate really helps a great deal with heading performance. These on headings are the reason the current generation of jumpers can do sites that were considered suicidal in the past (prior to circa 1998).

nose dressing is much more important for slider up, particularly for subterminal jumps.

A couple years ago I was taking photos and noticed something interesting. Slider down, canopies inflate from the outside cells inward.

So what you do to the center cell shouldn't have much effect. I tried packing with the outer cells exposed, and the center buried, but heading performance went way down.

freepack canopy inflation 101

all the exposed components of a freepacked canopy during the process of feeding out the lines from the tailpocket can torque the canopy, resulting in the canopy being turned before significant tension is placed on the lines. this is why i do not overexpose the nose on any packjob i do. pre-inflation of the canopy during linestretch is asking for problems. this is particularly important mesh slider up.

hmmm. So maybe the best way to pack slider down is to keep every nose cell closed. It seems a lot of people neglect the cells below the first fold in the container. If that area is open, it doesn't matter much what is done rolling wise etc.

And I like rolling or folding the stabilizer seems inward, like Jesse shows in his video. I think that helps prevent asymmetric inflation before line stretch also.

you don't really need to do anything with the nose, not even rolling it or restricting it. restricting the nose is better for mesh slider up though, but it has to be done in specific ways. (i primarily jump slider up but for perhaps over 100 jumps slider up with delays from 3 seconds to 11 seconds, i had perhaps maybe 2 serious off heading openings. all the rest were dead on heading). prior to the tailgate, openings were primarily tail first inflation openings, resulting in line overs and heading performance sacrifice.

see, the area of BASE jumping rigging is so different from skydiving rigging is that we are jumping a free packed canopy whereas reserve canopies are bagged, resulting in dramatically different opening dynamics. anything that turn the canopy during extraction process can sacrifice your heading performance. that's why 45 degree folding the stabilizers is a good thing (Adam Filipinno's suggestion - mispelled his last name). Even if you sacrifice a few feet for opening, you will have much more consistent openings. funny thing is that generationally, BASE generation 1 (the originators), realized much of this and came up with some rigging methods that were inferior to the tailgate but worked. That knowledge either was transferred or was lost in BASE generation 2, resulting in Mark Hewitt, BASE 46, developing the line mod because of a line over that nearly killed him.