slider down

guest · June 3rd, 2002, 07:40 PM

Hey, I have a question:

What are people doing to SLOW DOWN slider down openings? (besides putting the slider up, before anyone can say it)

I am still hurting from a friggin whacker last weekend. I have been told that my canopy seems to open harder than normal (I have nothing to compare it to), and am sorta starting to believe it. It doesn't matter if I am head high, level, or a bit head low at pull, they just friggin hurt.

Anyway, what can I do? I have thought about doing a triple stow on the primary (locking) stow. Or maybe for some weird ass reason, making the thing looser would work? Messing with the nose, like not pulling the center cell around the pack job at all. Tighter or looser on the tailgate?

Anybody got any ideas? I don't care if the friggin thing does two complete 360s and a McConkey before it's done opening, so long as it is a little bit softer.

Or is it just that I am a total vagina now that I have like 3000 jumps on the same Stilleto120 and I need to get hard.

Thanks for any input, folks.

d-dog · June 3rd, 2002, 08:25 PM

Three words: harden up tiger!

Seriously, I feel your pain. Primary stows scare me so I can't provide any advice on them. I do personally take a tighter tailgate, but there's a point of diminishing returns where a too tight tailgate just causes a really scary snivel followed by a hard "opening" once it finally pops. Could also kill you if it somehow stayed locked all the way in.

For me, the biggest thing I notice is that canopies packed for a while (in my book, more than 5 days or so) open noticeably softer than just-packed rigs. I've heard lucid theories on this, but who cares about the theory? Pack those rigs and let 'em season for a bit.

Also, of course, a more clapped-out canopy will generally open softer I think. Brand new ones act like ZP and tend to hammer.

Finally, many folks think vented canopes open harder, ceteris paribus, between 2 and 4 seconds than their unvented counterparts. Some people disagree, but how many of them are regularly riding vented canopies to 4 seconds slider down?

Someone more experienced than I should answer this question anyway, so forget everything I said above.

Peace,

D-dog
ddog@wrinko.com
www.wrinko.com

imported_Tom Aiello · June 3rd, 2002, 08:45 PM

>For me, the biggest thing I notice is that
>canopies packed for a while (in my book, more
>than 5 days or so) open noticeably softer than
>just-packed rigs. I've heard lucid theories on
>this, but who cares about the theory? Pack those
>rigs and let 'em season for a bit.

I heard there was a military study on square reserves a while back that came to the exact opposite conclusion (that a canopy left packed opened faster). Is that just an urban legend, or does anyone know for sure?

>Also, of course, a more clapped-out canopy will
>generally open softer I think. Brand new ones
>act like ZP and tend to hammer.

Here I go again, disagreeing.

I have a very, very old canopy (think 3000+ jumps--and no, no one ever ought to BASE jump with dodgy gear like that) that tends to slam open for some reason (other than it's cutting edge 1980's technology--I've compared it to other not so worn, but equally vintage--in fact identical--models). I theorize that the F111 wear pattern was somehow assymetric, leading to cracking openings (I'm pretty sure it has to be the fabric, as I've replaced darn near everything else on the canopy). Obviously, I don't jump it unless I'm willing to accept a hard opening (and I'm landing in salt water, generally). Still my experience tends to contradict your conventional wisdom.

I'm with you on brand spanking new gear (less than 20 jumps), though. I think those probably do open a bit harder, and generally fly better, as they are more "like" ZP.

>Finally, many folks think vented canopies open
>harder, ceteris paribus, between 2 and 4 seconds
>than their unvented counterparts. Some people
>disagree, but how many of them are regularly
>riding vented canopies to 4 seconds slider down?

I agree. Four seconds on a Blackjack with the ZP foreskin is just about enough to break my neck. I've had slider UP openings at four seconds that experienced observers commented "looked like slider down openings".

--Tom Aiello
tbaiello@mac.com

imported_Tom Aiello · June 3rd, 2002, 08:50 PM

I'd try rolling the nose (especially where heading is less important, and you're doing a lot of jumps--like Idaho). I've never really had that problem, but I did have a friend who had good luck fixing his consistent slammers by rolling the nose.

In my experience, a major contributer to hard openings is wing loading. What size is your hard opening canopy? And how are you loading it?

There's also the Frappucino approach--wear a neck brace. Looks silly, but I hear it works.

--Tom Aiello
tbaiello@mac.com

guest · June 3rd, 2002, 09:05 PM

Where are you?

Yexotay

d-dog · June 3rd, 2002, 10:15 PM

>I heard there was a military study on square
>reserves a while back that came to the exact
>opposite conclusion (that a canopy left packed
>opened faster). Is that just an urban legend,
>or does anyone know for sure?

For me, it's from personal experience. Mostly my rigs are unpacked in a day or two. The dozen or so times I've had one packed longer this winter, and then taken it 3-4 slider down, I was pleasantly surprised at the (relative) lack of spank. I then asked an experienced jumper about it and he agreed that it was "common wisdom" with which he agreed.

As I understand it, the theory is that a recently-packed rig has more trapped air in it, and thus pressurizes faster since the air during deployment has plenty of nooks and crannies into which it can quickly flow.

In contrast, a rig left packed in the trunk for a week or two has seen most of the air in the F-111 canopy slowly get pushed out through squeezing from the packjob and the weight of gravity settling the rig over time. It's certainly true that long-packed canopies are smaller and float around more in the container.

I've even heard that some jumpers will pack a rig immediately before a super low freefall to maximize opening speed. Pretty cool trick - gotta hand it to those Aussies.

Anyway, I know that from my own experience I'd be real hesitant to take a rig that had been sitting in my trunk for a while and jump something super low. I mean, I visualize the canopy hitting line stretch and just sort of hanging there for a few moments before even the bottomskin does much pressurizing, let alone air flowing in the nose.

I'd not expect the same with a ZP canopy, but since I've never actually jumped a ZP canopy what the heck do I know?

My theory on your clapped out canopy opening hard is that it has a slightly different geometry even than another "identical" canopy. The subtle nudge of geometry could just set it up to be a hard opening canopy due to some weird, non-linear aspect of fluid dynamics (sort of like a self-organizing criticality of sorts, if you are familiar with that mathematical literature).

My point is that, over time, one would expect it to open less hard as it gets more clapped out. However, a hard opening canopy will probably not become a softie just because you jump it a few hundred times. There just seem to be some canopies that open hard, even compared to identical twin brothers. Who knows - maybe somebody put bad voodoo on them at the factory?

Peace,

D-d0g
ddog@wrinko.com
www.wrinko.com

guest · June 4th, 2002, 08:09 AM

Hey, do any of the manufacturers have any input on this subject? Yall will definitely have the beta...

**Tree** · June 4th, 2002, 10:28 AM

CR reccomends micro-reefing the tail to increase the chance of a nose first inflation. If the tail gets inflated first it does seem to "slam" much harder than if the nose inflates first. Basically you just put extra folds in the tail and c-d flake. Also, when you cocoon with the top skin of the center cell, tuck it in between the b-c and c-d flake nice and tight. All of this is supposed to make the nose start inflating before the tail, and it does seem to make the openings a little nicer.

Trash packing seems to work too.

Tree ;-)

**space** · June 4th, 2002, 11:36 AM

maybe try shorter delays with no slider. just a thought.
you never told what delay...all is relative.
take care,
space

**crwper** · June 6th, 2002, 05:32 AM

>I heard there was a military study on square
>reserves a while back that came to the exact
>opposite conclusion (that a canopy left packed
>opened faster). Is that just an urban legend,
>or does anyone know for sure?

I know, the thread's kind of old, but I'll resurrect it anyway. I think the study you are referring to is referenced in Poynter's Manuals or something. It actually found that canopies which have been packed for longer open slower, but not by much. Most of the "slowing" occurs in the first few days, then after that it sort of plateaus.

Michael

guest · June 6th, 2002, 11:53 PM

Yuri showed me this one, & it really works for us.
Roll the 3 cells either side of the nose tight, obviously not the center cell. Also micro reef the tail as per CR's packing instructions. This definitely
gives me softer openings on my 3 sec + jumps, of which we do a lot.
We've also found more consistant on heading openings by rolling the nose with slider up & down.
For ultra short delays, open up all the cells, & puff up the center cell so it gets a head start on the rest of the canopy.
Safe ones!
Karl:-)

**Mike** · June 7th, 2002, 07:07 AM

There is not much you can do to ease the opening shock of a slider-off canopy, at least not by modifying your pack job. Don't monkey with extra stows, folds, or any of that nonsense. It over-complicates your pack job, and it can't help that much anyway.

>It doesn't matter if I am head high, level, or a bit >head low at pull, they just friggin hurt.

I know for a fact that if I'm a little head-down at line stretch, I'm in for some extra pain. If my delay is between 2 to 4 seconds, I'll usually do a slow-rotating gainer, or a back layout. That way I am head-high, virtually upright at line stretch. It's much, much easier to take the shock if you're already standing up. You don't get the whiplash effect that way.

One thing you must do is relax. It's hard not to tense up and hold your breath in freefall, when you know you're about to get hit by a truck. Try to make a conscious effort to breath, and don't anticipate the opening. This is akin to shooting a high-powered rifle. If you anticipate the kick, you will tense up and flinch. Try to let it surprise you.

Also, pay attention to where your head is aimed. If you're flat and stable, but also looking at the ground, the weight of your head is going to snap your chin into your chest and strain your neck as well. Keep your eyes on the horizon; this will usually keep your head above your neck.

>I have been told that my canopy seems to open >harder than normal (I have nothing to compare it >to), and am sorta starting to believe it.

Wrong. That doesn't make sense. Your canopy will only seem to open harder if you believe that it does. This just gives you an extra reason to tense up in freefall. Forget about it.

Hope this helps.

guest · June 7th, 2002, 09:03 AM

thanks, the rifle analogy makes some sense.

The not looking down thing kinda sucks because I like the ground rush, but I guess I can get my eyes back on the horizon after I pitch.

I may give Karl 552 and Tom's nose rolling thing a try as well. Plus I am gonna give slider up a try next time I hit our friendly local big span, assuming the heat is somewhat worn off.

If anyone has any other input, that would be great.

You also make a good point re head down-ness. On about half my jumps, I have noticed a tendency to pitch down AFTER the pitch. It is the weirdest damn thing. I mean, I can see video of myself launching chest first, head high, taking three seconds in that attitude, pitching, and THEN i start to pitch down a bit. Not a lot, I'm maybe 5-10 degrees low at line stretch, but enough to be noticeable (this is what happened on the whacker from hell, plus I was looking down).

I am wracking my mind trying to picture what I am doing with my body after I pitch that could cause this, but can't come up with anything. I assume that looking down would aggrevate the situaton but this has happened when my eyes never left the horizon as well, with a similar launch style.

any input on this? I've seen some other people do the same thing on occasion. is it just one of those things? or do i just suck?

idaknow, i think i just need to jump more.

guest · June 7th, 2002, 09:33 AM

I am curious to what canopy you are jumping? I also had this problem but never realized how hard I was getting wacked till I got my V-tec. I was jumping a mojo and a fox v-tec back to back, now I had something to compare to. My fox seemed to open a lot smoother, less wack. Then back up with my mojo for a three second delay with my mojo. Dislocated my bum shoulder. Others may tell you the opposite, but I have seen this happen to one of my other buddies. Borrowed a rig, doing double backs, the mojo hurt him. my two cent worth:-)