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I'm having issues with my slider coming about 2/3 of the way down the lines, then getting stuck until I pump the brakes to get it the rest of the way down. It's not a huge deal because the canopy feels controllable even when the slider isn't all the way down but I wanted to see if anyone else had the same issue. If so, were you able to fix it so that the slider comes all the way down on opening?

It's a brand new Troll 265 with ZP, but no vents and I'm loading it light-ish (0.65). The slider is big mesh. I'm wondering if it's the light loading. I'm also wondering if it has something to do with the canopy being brand new and maybe it'll change as it gets broken in.

Here are links to two videos. One is a slider up PCA at the Perrine. If it were just the PCA, I'd blame it on the low airspeed but I get the same thing when I freepack it into a skyrig and open from terminal. I used direct slider control in the sky, but not off the bridge.

Perrine SU PCA:
https://www.youtube.com/watch?v=s1m8zPfJ1vI

Freepacked Sky Jump:
https://www.youtube.com/watch?v=6b-FCLFRNN4

One thing that comes to mind immediately: Is the slider the correct size for the canopy? It may be worth finding out what the spec is for that canopy and checking to make sure you have the right one.

Typically the manufacturers send the correct bits and parts, but not always...

~ Chris

Also, are your steering lines routed through the slider grommets? The pressure from the steering lines is necessary for proper slider movement...

~ Chris

Yeah, the lines are routed correctly through the slider grommets and guide rings. I'm pretty sure the slider is the right size but I'll double check.

One other thing to check, though I can't say it would have a huge effect, is to make sure the slider is on right-side-up. That is to say, make sure the smoother, finished side of the grommets are facing the bumper stops, and the somewhat-less-smooth side of the grommets are facing the canopy.

This should aid the slider in moving somewhat more freely down the lines than up them...

~ Chris

Is it standard F-111 fabric (aside from the ZP). Or the ultralight (PN-9) material?

It's standard F-111. I sent Stane an email asking about it just now. Stane is the man but I just hate to bug him some more because I've been asking him so many other canopy questions lately :) I'll post whatever info I get from him.

... that's why. make more jumps and the problem is solved

What changes in a few jumps to make the slider come down? Or are you joking?

watching perrine i'm not surprised as it's a really low speed opening, there is just not enough pressure.

at terminal:
do you roll the nose or parts of the outer cells? if so: don't
do you open-up the centre cell after the first s-fold? open it bigger or put it over the s-fold.

if the problem stays , then pull directly out of the track, not in the box.

Do people normally go from track to box to pull? If so, I've been abnormal for 20 years.
Is that your experience?
Take care,
space

The slider should be coming all the way down. He could have rolled the nose super tight and put clothes pins on it and it shouldn't have any effect on that. All that stuff loosens up and/or completely comes out between extraction and bottom skin expansion.

I disagree. If that was true, then there would be no reason to tie the slider down on SD jumps. There is reason.
Take care,
space

Can the slider get stuck if the shallow brake settings are too deep?

I would think that it could happen if one's brake settings are too deep or too shallow.
tcs

Yes.

But every Troll I've ever worked with has had good factory shallow settings for driving the slider well.

I rolled the outside nose cells in for the skydives, but not the bridge. My best guess is that it's the light wing loading. I've lost about 25lbs since I ordered this canopy and now my exit weight is only about 180-185lbs, which puts my WL on the Troll 265 around 0.65. I'm a fan of light WL on SD, but maybe I want to go a little heavier on SU. I might experiment with jumping with water bottles in my pocket or something to see if it makes a difference. In the meantime, I'll just pull high and if nothing changes, I might sell it and get the same canopy, but one size smaller.

I've seen little people on really big canopies and it definitely snivels a little bit more and isn't as pretty as a proper sized canopy, but 0.65 isn't too light at all and you shouldn't be having that slider problem! Have you checked on the slider dimensions? Have you heard anything from the manufacturer about it?

Do you untwist your brake lines for every jump?

Yeah, I untwisted the lines for each jump. I heard back from Stane and he sounds like he thinks it's mainly the light loading and that I can make up for it by adjusting the trim:

"- PCA from the bridge : it is low speed
- skydive jump : you can play with brake settings or use bigger big mesh slider

- aerodynamic solution : steeper line trim . This moves your CG towards the leading edge and compensates for lighter wing loading . We can calculate the new line trim , but you'll have to change the suspension line lengths , adjust brake settings and do some skydive test jumps ."

I'm taking it on a slider-up trip in two weeks along with two other rigs, so I'll probably just try to jump the other two rigs more and when I jump this one, I'll pull higher. Like I said, the canopy feels controllable even before the slider is all the way down. When I get back from my trip, I'll decide whether to downsize or mess with the trim.

I double checked and it looks like the slider is on upside down. I'll flip it over just to be sure but I don't see why it would make a difference.

Edit:
If I flip it over and it fixes everything, it'll be a good learning point I guess. It'll be a good experiment. I think I'll have time before my trip. Does anyone know why we make the sliders face a certain way? It seems pretty symmetrical.

Apparently brass grommets are supposed to be the opposite way of steel ones. Like I said, I'll flip it over and try.

Unless we are in bizzaro world the direction of the grommets should make little difference. One does want the smoother side down because friction on a rough imperfection in the grommet in the wrong configuration is more likely to damage the lines but this is very unlikely. It would not delay the opening

that hasnothing to do with a slow slider. are you making a joke?

Geese...I mean Grease the lines. I rub goose skin on them because it's water repellant and tastes delicious.

No I'm not joking. Twisted brake lines = more resistance to the slider grommets as they are sliding down.

Untwisted, straight break lines = less resistance.

Yes I should have written "...for slider up jumps..." as I was referring to this:


Frank.

line twists also make a line shorter

Consider the wrath of tensions. to clarify, NSEW. each direction has an influence. Why does the slider go down in one condition and get blown back up in another? This is a no brainer for me. Change deployment speed or mass. Assuming that one has a correct slider span and chordwise. Chordwise i dont know much about but it is clear to me that spanwise of the slider should have the center cell width. Think on this. NSEW. North south should have more influence than East and West. But East West brings the slider down.
TCS

I am a lighter guy on a lighter loaded troll and I have had zero issues with my slider. Im145lbs jumping a troll 245(260pia) I really doubt that is the issue. I've jumped a 260 troll and had no issues with it either.

I had the same problem on a brand new Seven 280. I ended up changing the slider. What size rubber band and how many wraps are you using on the primary stow?

I'm using a regular skydiving rubber band with two wraps as the primary stow. The direct control is a skydiving rubber band cut to half its width with two wraps for skydiving (no direct control for the bridge jump).

How did you change your slider? I'm already using big mesh, so I guess all I could do is go bigger dimensions but still big mesh.

I had the same problem with a Seven 280 (w/ ZP leading edge) loaded at ~.7, which I could never resolve, no matter what changes I made with the reefing. After it apparently started affecting heading performance in Lauterbrunnen, I decided to sell it after returning home from the trip.

Ive had this problem on every brand new canopy ive jumped, or rather with every brand new set of new regular weight dacron. Goes away after a while. I dont think it has anything to do with twists or other obvious stuff. The subterminal depolyment obviously doesnt help either, but id be surprised if it doesnt go away in the next 40-50 jumps, especially at terminal.

If its really bugging you, open the nose all the way, dont use direct control, and jump it out of the plane, I think your slider will come down nice and quick.

So if i want a slower opening i should twist my brakelines?
Sure one should strive for packing perfection. but in the end the massive truck of a BASE canopy loaded at 0.75 lbs per ftsq doesnt really care a about a few milliseconds or millimeters on deployment. one needs about a 6-8 loading for this to make a sig diff. the prob with twisted brake lines is they have a tendency to half hitch. that is the prob. forget friction or line shortening. tension knots are the prob from twisted control lines.
tcs.

Now you're making a joke.

jws3 has made it clear that twisted brake lines are not the problem:

In the other world I've seen problems with stuck sliders on lightly loaded canopies go away when the brake lines have been untwisted.

In jws3's case, twisted brake lines are not the problem.
Frank.

If you want to fight/argue, we take it to pm ok?
tcs

So I flipped over the slider so it's facing with the tape up like the manual says and it seems like it might be better but it's hard to say for sure:

https://www.youtube.com/watch?v=BVSXtu1fljE

It still doesn't come all the way down immediately, but I feel like it's good enough and it sounds like other people have seen it get better after a few jumps.

Sure, if you want.

Youre right. Wrong place wrong time.

Drive-by with no explanation?