syntax 0 #1 May 16, 2005 I jump an electra 190 and lately i havent been collapsing the slider after opening.I'm not worried about losing speed.Apart from the occasional flapping,can anyone see a problem with this? Cheers!------------------------------------skydiving...the grounds the limit! Quote Share this post Link to post Share on other sites
Kris 0 #2 May 16, 2005 If there are any burrs or nicks on the slider grommets, they can chew through the lines easier. It also makes that really annoying sound. Remember, only you can prevent Slider-Flapida.Sky, Muff Bro, Rodriguez Bro, and Bastion of Purity and Innocence!™ Quote Share this post Link to post Share on other sites
piisfish 140 #3 May 16, 2005 Quote It also makes that really annoying sound.. unless he is a Harley rider... scissors beat paper, paper beat rock, rock beat wingsuit - KarlM Quote Share this post Link to post Share on other sites
EvilLurker 2 #4 May 16, 2005 No, there's no problem associated with it, it's just a lot quieter. I have a rig with a collapsible and one with a non-collapsible and they both act exactly the same. I guess the "grommet burr" thing has merit, but you probably should worry more about the damage that's doing to the top of your lines during deployment a lot more than while it's flapping, since it's got a LOT more pressure/friction during that time. Quote Share this post Link to post Share on other sites
billvon 3,119 #5 May 16, 2005 >Apart from the occasional flapping,can anyone see a problem with this? Cheers! You can prematurely wear slider bumpers and line attachement points, especially the outer lines on either side, since the flapping of the slider is constantly pounding the grommets into the lines/bumpers in those areas. If you regularly replace linesets and bumpers, though, it shouldn't be a problem. Quote Share this post Link to post Share on other sites
MakeItHappen 15 #6 May 16, 2005 Quote I jump an electra 190 and lately i havent been collapsing the slider after opening.I'm not worried about losing speed.Apart from the occasional flapping,can anyone see a problem with this? Cheers! I do not collapse my slider. Keely took a picture of me landing that showed the slider position. It's posted someplace on this web site, but I don't know where. It's no big deal. Ram-airs were jumped for years and years and years without collapsible sliders. For some reason my slider does not flap, thus it does not make any noise. Collapsible sliders were introduced to reduce drag. It had nothing to do with wear and tear on lines, line attachment points or bumpers. If you have a burr on the slider grommets, collapsing the slider will be the least of your concerns. .. Make It Happen Parachute History DiveMaker Quote Share this post Link to post Share on other sites
AndyMan 7 #7 May 16, 2005 Please read this post in the Incidents forum: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=452847;page=3;sb=post_latest_reply;so=ASC;mh=25;#467069 Where the combination of not pulling down or collapsing the slider and the use of PD Soft Links may have caused a malfuction. In that particular case, the jumper did not cuttaway from the spinning malfunction and died. Otherwise, while you may not notice the speed change when you collapse your slider, it can make a significant impact to the slow speed flight characteristics of your canopy. Why do you care? You may find that when you collapse your slider, your no-wind landings get a lot better. My big question though, is that since you have a collapsible slider.... Why not use it? _Am__ You put the fun in "funnel" - craichead. Quote Share this post Link to post Share on other sites
larsrulz 0 #8 May 16, 2005 Quote My big question though, is that since you have a collapsible slider.... Why not use it? Some people wish to concentrate on what is happening under canopy, which is certainly a valid endeavor, and if they don't wish to collapse their slider, then there's no reason they have to. An equally valid question is to "why use it?", if someone doesn't want to, then there is no reason to. The incident you posted is a problem because the jumper did not have slider bumpers and did not bring the slider to the bottom of the risers. To the original poster: Gary Peek, who is a master rigger and regional director, is very knowledgeable about skydiving gear, and he doesn't collapse the slider on his stilleto, so if you don't wish to then I personally wouldn't worry about it, but no reason not to throw the question by your friendly rigger anyway! I got a strong urge to fly, but I got no where to fly to. -PF Quote Share this post Link to post Share on other sites
EvilLurker 2 #9 May 17, 2005 I alwsys waited until I had cleared my airspace/unstowed my toggles and set a course for the landing area before I collapsed my slider (or until that annoying flap*flap*flap got on my nerves) and I never noticed any difference between before and after. I realize that there is (supposedly) a difference in drag, but I'm not so sure that the "flat" slider flopping in the breeze is any lower than the "fat" collapsed slider plowing through the air, in fact there could well be more drag with it collapsed. Don't challenge me to prove it, though, it's just a half-baked theory. Quote Share this post Link to post Share on other sites
teason 0 #10 May 17, 2005 I did about 1000 jumps on my Sabre and always collapsed my slider. I had a line change and my gear was used as instructor gear at the dropzone. Those jumping it didn't stow the slider and 150 jumps later, my outside linse show major fuzz where the slider rubs. (although I admit it could also be velco damage from throwing the lines over the shoulder) Also, your slider rubbing is what causes your lines to go out of trim. Friction=heat. Heat shrinks nylon. That's why the outside lines get shorter than the inside lines. I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet. Quote Share this post Link to post Share on other sites
kelpdiver 2 #11 May 17, 2005 on my triathlon, it doesn't even seem to reduce the flapping noise that much when I collapse it. And yeah, does seem like it presents a fatter cross section with the bunching in the middle. But it's easy enough to do. Quote Share this post Link to post Share on other sites
EvilLurker 2 #12 May 17, 2005 Quote Also, your slider rubbing is what causes your lines to go out of trim. Friction=heat. Heat shrinks nylon. That's why the outside lines get shorter than the inside lines. So, if I do a cross-country on my PD-210 with that non-collapsible flapper I'll be at risk of my lines melting right in two? Thanks for the warning. Quote Share this post Link to post Share on other sites
sundevil777 102 #13 May 17, 2005 Quote doesn't even seem to reduce the flapping noise that much when I collapse it. Adjusting the position of the slider grommets up/down will change the fluttering - at least you can minimize itPeople are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am Quote Share this post Link to post Share on other sites
ianmdrennan 2 #14 May 17, 2005 Higher airspeed = more flappage. More flappage = more friction. More friction = greater line shrinkage (spectra). So yes, he's right they will shrink, and yes you're wrong they won't melt Blues, IanPerformance Designs Factory Team Quote Share this post Link to post Share on other sites
EvilLurker 2 #15 May 17, 2005 You sure the shrinkage described isn't due to the slider initially coming down the lines during deployment where the spreading force is huge, and the slider flapping is so minor that it can be ignored? My belief is that the nylon has to reach a pretty high friction/temperature before it's going to shrink, and your slider flapping a little bit has nowhere near the energy associated with it to even be CLOSE to causing friction-induced line damage. And exactly why wouldn't they melt? Enlighten me. Quote Share this post Link to post Share on other sites
billvon 3,119 #16 May 17, 2005 >You sure the shrinkage described isn't due to the slider initially >coming down the lines during deployment where the spreading force > is huge . . . That causes the majority of shrinkage. >and the slider flapping is so minor that it can be ignored? It is much less of an effect. But opening lasts 3 seconds and the canopy ride can last 6 minutes. That's a long time to batter away at the lines. >My belief is that the nylon has to reach a pretty high >friction/temperature before it's going to shrink, and your slider >flapping a little bit has nowhere near the energy associated with it >to even be CLOSE to causing friction-induced line damage. Take a look at the lines near the links of an old spectra-lined main with bad bumpers. You'll see the damage. >And exactly why wouldn't they melt? ?? Same reason that your hands don't melt when you rub them together hard - but they do get warm and you do lose a little skin. Fortunately, the skin on your hands is always growing back. Quote Share this post Link to post Share on other sites
diablopilot 2 #17 May 17, 2005 It causes premature wear on microline at the risers.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
diablopilot 2 #18 May 17, 2005 Quote It had nothing to do with wear and tear on lines, line attachment points or bumpers. It does in some ways. Quote Ram-airs were jumped for years and years and years without collapsible sliders. And they were jumped without mircolies for ages too. I've found the worst wear from that on Vectran linesets.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
teason 0 #19 May 17, 2005 JP makes a good point. Dacron lins aren't nylon, they are polyester. They wear differently than nylon. TimI would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet. Quote Share this post Link to post Share on other sites
