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Quick question for BASE jumpers experienced with slider-up jumps:
How dangerous is it to pitch early when you are packed slider-up?

Background: an anonymous poster was razzin' me about taking a
short delay @ Bridge Day and said what I did was not a good idea.
I personally think taking 6+ seconds without a slider to be crazy!!

His or Her 2 cents:
having a slider on between 4 and 6 seconds is statistacly dangerous,
1 to 2 seconds would be pretty scary at even slower air speeds. it can
cause all sorts of problems. you should make a post on this site to
see what the experts have to say about it, maybe (we) will both learn
something?

4 seconds s/u is ok, but going any shorter than that is not a good idea on most objects. Delays shorter than 4 sec s/u increase the probability of off-headings greatly. Annie from Apex was recording and keeping data on configurations during the competition at Petronas in 2001. She'd be a good person to contact

As Lonnie said. However I personally would not take a 4 sec silder up off a solid object (cliff). Fuck that! I take 3 and go slider down. Yes I am Gay Nick (even though I'm straight) so call me a pussy as much as you want.

Off a solid object I want at least 5 true free fall seconds before pitching if I go slider up, otherwise it's three and down.

Yeah I agree Nick. I should have added that in there.
There is that fine line @4sec anything solid behind you, either go shorter S/D or make sure you can do a solid 5 for S/U

I agree with Lonnie and Nick regarding solid objects, but if I read your post correctly, the question is if it's safe to go 4 seconds slider-up at Bridge Day. If you're far enough from the nearest impact to deal with off-heading and/or a line twist or two on opening, and if you can still set yourself up for a good landing after that, then 4 seconds seems like no problem at all. Am I missing something?

Michael

At Bridge Day, you're fine.

The problem with short slider up jumps is that you don't have enough airspeed to drive the slider well, and the opening ends up slow and inconsistent, with worse opening heading percentages. On Bridge Day, that's not an issue.

Lonnie, Michael, Nick & Tom A.
thank you guys for replies & input.

Till BD I had never jumped with a slider.
A buddy of mine who was crashing in my
room had an extra and offered to let me
use it. I decided to jump slider-up just
for the experience and not because I had
any plans to smoke it low.

At the moment I do not even own a slider
but plan to make one for myself eventually.
Any suggestion fellas on large or small mesh?

what PC are you using ?

Hey Airdog07,

I used a 42 inch apex vented ZP PC from Aslyum.

At the moment this PC only has 3 jumps on it

One second at the Perrine is absolutely not a problem.

Imagine a 600'ish cliff. What everyone is saying is that you won't want to go slider up and take it all at 3.5secs. But you'll have to lose some of the groundrush and go 3-3.5secs slider down, and brace your neck...

Short delays slider up work perfectly "most" of the time...

  4-6sec. delay with 42 PC there should be no problem
but if you are going for 8-10sec. you need to use smaller PC or it well open hard specially if you have vent,
with 36 PC 8-10sec. well be good, but if you dump early like 4-5sec you might have hesitations,
but I did 4-5sec before with 36 PC because that was only PC that I had at the moment,

It depends on a few things. My default position with a slider is large-hole mesh. If you're jumping a vented canopy on terminal jumps, you might find the large-hole mesh slider is a bit aggressive. Moving to a small-hole mesh slider will soften up the openings a bit, without a huge change in your opening altitude or heading performance.

If you're making your own slider, be sure to get accurate dimensions for the manufacturer's slider for that canopy size. Changing the dimensions of the slider can have a significant impact on opening. It's probably not a variable you want to play with at this point.

Michael

I'll second that. I have a couple dozen jumps at the Potato bridge (1-2 second delay) slider-up with no significant heading issues. The problem with a slider is not necessarily that it changes your mean heading performance, but that it increases the variance. As Tom said, this is because the canopy spends a lot more time in a configuration (slider at the stops) where rotation is most likely to occur.

Michael

Don't know how well this Pic. shows up. if it does, You can defiantly see the way the canopy gets suspended when between Slider-up and the taunt bridal and PC pull. Also the slider Support Tape bent upward from air flow before the bottom skin span-width inflation will force most of the friction on the outer line groups through the slider-grommets as it gets forced down the 4 line groups to the bumpers.
.
edit to add:
Ah cool, when you click up the Attachment in the Post.Hold curser on the pic. then put the curser on the (expand to regular size) icon. and click.
.

Ray, great photo, thanks!!

Start with large mesh and take it from there.

If you're openings are really harsh and you're taking 9+ seconds, try a fine mesh (marquisette) slider.

[hopefully I spelt that right!]

As already mentioned, get the slider dimensions right!