Thanks for the help guys. And "I" am not trying to slow my openings. This is just what I've heard others do, since their canopies tend to open hard (one jumps a V-tec). As I said, I've never jumped my canopy at terminal, so I don't know how hard it's going to open. I don't want to slow it down on my first terminal and snivel into the ground. I just wanted some clarification, since I've heard two different stories on tailgates and sliders. C-ya!!
Blue Skies,
Josh
I never used to rubber band the slider either, my reasoning being that one doesn't do it on skydiving reserves, then why should I ? I received several comments on it while in Malaysia.
Anyway a few months later I received the hardest BASE opening of my life on a 6 sec delay from the waterfall in lauterbrunnen (Staubach). This was of course slider up. I remember that my pack job was very neat and I had good body position, I was current after all, with that being the 20th jump that week. It absolutely reemed me and people on the ground thought I had jumped slider down. I got a whiplash neck thing that went deep inside my skull, felt like I had a swollen brain for a few days.
There is only one explanation, and that is slider dump. I rubber band the slider now. I think that with better no orbiting pilot chutes, that simply pull up, and with neat pack jobs with good line tension, the chances of the slider whizzing down the lines after the last line group leaves the tail pocket stow are much greater.
/Lukas
Pointing out at first that I completely agree with Tom: each BASE canopy needs its own amount of slider/its own amount of wraps (min 1, max 2); so each jumper needs to find his own solution that works for him.
Second: we need to rubber band the slider only to stage its deployment (=coming down only after line stretch), not to absolutely refrain slider from coming down neither to delay the opening of canopy in a direct way!!!
Third: even if at terminal, there is (nearly) no air (=force arising from air) that can keep the mesh slider up, in fact a mesh slider has got no solid fabric!!!
Fourth: we must remember the principle of inertia in physics to understand why premature descent of mesh slider is possible (very, very difficult but still possible). You are falling at terminal, let us say, at 54 m/s, everything is falling at 54 m/s, your body, your harness, your container, your PC (stowed into BOC), you canopy+mesh slider+lines (packed into container. Principle of inertia says that a rigid body going at a certain speed, it wants to remain in that status (i.e., at that speed), unless something (= a force!!!) comes to stop it from going at that given speed. When the right time comes, you release your PC in air: let us say (for sake of simplicity) the PC stops in air because it is made from cloth and has a shape and a weight and so on. Now you have this "anchor" digged in the air that wants to refrain everything else: at this stage, everything else (body, container, canopy+mesh slider+lines) is still falling at 54 m/s and wants to remain falling at 54 m/s, unless something stops it from falling (your PC in the air).
PC starts pulling and then stretches the bridle and remove shrivel flap/pin opening container: at this stage, canopy+mesh slider+lines are still falling at 54 m/s. PC starts stretching another bit of bridle, then starts lifting/pulling the canopy out of container. The bottom part of canopy (=lines and mesh slider) are still falling at 54 m/s and want to keep on falling at 54 m/s: a worn velcro in the tail pocket or some other condition COULD cause line dump: lines (quite heavy and still travelling WITH the jumper at 54 m/s) could come out of T.P. all in once (line dump) while the canopy has just finished to stretch in the vertical direction.
The only refraining "item" at this stage is the PC that pulls the bridle that pulls the top of canopy: the rest of "stuff" (lines (inside T.P.), mesh slider, jumper's body) is not (yet) refrained from falling. And keeps on falling down at 54 m/s.
The mesh slider (which is also travelling downwards at 54 m/s and wants to keep falling at 54 m/s), if it doesn't find any sort of impediment (like the lines stowed in T.P. and/or lines stow with rubber band under T.P.(=indirect slider control)), could keep on falling at 54 m/s together with the lines (line dump), so travelling down the lines until a stage in which lines are not yet stretched but canopy fabric starts expanding (primary inflation).
Remember, there is (nearly) no air (and so no force) that can keep the MESH slider up.
So, you could come to a point in which canopy is more or less open/starts opening, mesh slider is somewhere half way down the lines and lines themselves are not completely stretched out. I think that would result in a very hard opening indeed.
This is just my personal opinion based on physics considerations/principles. I would like to hear someone else's opinion/comment on the inertia principle I exposed above.
In the end, I think that if you do it properly, according to your own rig, and so picking up the right amount of mesh slider fabric, and rig it with the right rubber band (small flat rubber band cut in half lenghtwise) with only ONE wrap (to start with and possibly moving to TWO wraps, just in case and if needed), it cannot cause you any harm: but, if in doubt, don't do it!!! Have an experienced jumper to show you LIVE how to do it.
Stay safe out there
Blue Skies and Soft Walls
Andrea :D
#689
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