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87SupraT Nov 8, 2005, 1:29 PM

Slider Up/Down Idea

I had an idea, it may be absolutely stupid and far-fetched, but I want some feedback :).

What if you could do a Slider-Down jump with the brake lines through the slider grommets and the slider in the up position? My idea is using a collapsible slider, in the collapsed form. So basically you have a slider quatered against the stops but it is collapsed. This allows the brake lines to be ran through the slider like normal, but the slider won't do anything, but possibly make the slider down jump a tad smoother on opening. Would there be any benefit to this setup? Just thought I would share an idea.

Dale

460 Nov 8, 2005, 1:40 PM

Re: [87SupraT] Slider Up/Down Idea

in the event of a line over, the line responsible for this is generally a brake line. the jumper releases the toggle on the offending side using a line release modified toggle system. if the brake lines are routed through the slider, upon release of the toggle, the toggle will most likely hang on the riser grommet, causing uncertain results. the slider is generally attached to the front risers when jumper slider down (vs slider removed). in the case of a toggle/grommet hangup, the lineover may not clear. there are many other unpleasant scenarios that could easily occur. the list goes on and on.

87SupraT Nov 8, 2005, 1:43 PM

Re: [460] Slider Up/Down Idea

I see. Doesn't routing the brake lines through the slider grommets lessen the chance of a line over, as opposed to running the brake lines outside the slider?

Dale

dploi Nov 8, 2005, 1:43 PM

Re: [87SupraT] Slider Up/Down Idea

In reply to:

What if you could do a Slider-Down jump with the brake lines through the slider grommets

You could, and it would be a very bad idea. There's a reason why we don't do this.

JaapSuter Nov 8, 2005, 1:46 PM

Re: [87SupraT] Slider Up/Down Idea

In reply to:

but the slider won't do anything

Why would the slider not do anything? At low airspeeds, the difference between a mesh or sail slider are neglectible. It still keeps the lines together at the top delaying canopy inflation until the slider comes down, regardless of whether it is collapsed or not. As such, it turns a quick slider-down opening into a slower slider-up opening, rendering it useless for many slider-down objects.

DexterBase Nov 8, 2005, 1:46 PM

Re: [87SupraT] Slider Up/Down Idea

I'm going to think this one over for awhile. At first glance, I don't think anything horrible is going to happen. Basically, you're talking about putting the slider up but having it collapsed so that there's little or no air resistance right?

At low airspeed, there's very little air resistance working against the slider anyway, so little that the type of slider (large mesh/small mesh/sail) is almost irrelevant under two seconds.

If you were to jump an otherwise properly configured rig with a collapsed sail slider, the only difference from a normal slider would be the aspect ratio. The left and right line groups will be the right distance apart, but the front and rear groups will be closer together than intended. This might give you some bad heading problems, but nothing catastrophic should happen.

I don't see the reason why you'd need to do this.

What are your thoughts 87SupraT? What made you ask this question?

Like I said, this reply is not very thought out, I'll chew on this for awhile and see if I come up with any other ideas.

87SupraT Nov 8, 2005, 2:00 PM

Re: [DexterBase] Slider Up/Down Idea

In reply to:

Why would the slider not do anything? At low airspeeds, the difference between a mesh or sail slider are neglectible. It still keeps the lines together at the top delaying canopy inflation until the slider comes down, regardless of whether it is collapsed or not. As such, it turns a quick slider-down opening into a slower slider-up opening, rendering it useless for many slider-down objects.

I was kiting a canopy last night, and had the slider uncollapsed and quatered, it took some work to get the slider to come down at about 8 mph winds. When I collapsed it and tried to kite it, it came down almost instantly. This was around 8 mph winds. That is the background of the idea.

In reply to:

I'm going to think this one over for awhile. At first glance, I don't think anything horrible is going to happen. Basically, you're talking about putting the slider up but having it collapsed so that there's little or no air resistance right?

At low airspeed, there's very little air resistance working against the slider anyway, so little that the type of slider (large mesh/small mesh/sail) is almost irrelevant under two seconds.

If you were to jump an otherwise properly configured rig with a collapsed sail slider, the only difference from a normal slider would be the aspect ratio. The left and right line groups will be the right distance apart, but the front and rear groups will be closer together than intended. This might give you some bad heading problems, but nothing catastrophic should happen.

I don't see the reason why you'd need to do this.

What are your thoughts 87SupraT? What made you ask this question?

Like I said, this reply is not very thought out, I'll chew on this for awhile and see if I come up with any other ideas.

The reaon I asked this question was from the kiting experience I spoke of above. I am not saying this is a full proof plan for anything, I just wanted to get it out there, and see what more experience and knowledgable people had to say. My idea for it, would probably be instead of the canopy just plopping open, it would have a slightly uniformed opening, being as the slider keeps the lines more organized and slightly delays the opening. Could this possibly reduce line twists too? Again, I am not speaking from experience, just a curious mind.

Dale

pringles Nov 8, 2005, 2:12 PM

Re: [DexterBase] Slider Up/Down Idea

Im with dexterbase. I think that it wouldn't cause much problems except for heading issues ( if i understand his post correctly). I feel that the way your thinking it serves the same pourpose as the tailgate though. So it would fall into the same catagory as using the tailgate and still routing your control lines thru your slider and guide rings.

DexterBase Nov 8, 2005, 2:13 PM

Re: [87SupraT] Slider Up/Down Idea

I think if anything, it would increase the chances of having linetwists.

TomAiello Nov 8, 2005, 2:31 PM

Re: [87SupraT] Slider Up/Down Idea

If you are going to manufacture a slider for this purpose (which you'll have to, because there are no collapsible BASE sliders) why not just make it an "outline" slider (i.e. no fabric in the middle of any kind, just the outside tapes)? It would be cheaper and create less problems.

Alternately, you could use a "jock strap" configuration, with the strap joining just the rear risers (and presumably your control lines).

What is the upside of using this arrangement? Maybe I'm slow on the uptake, but I'm not really seeing one. If the slider acts enough as a reefing device to inhibit a line over, then it will act as a enough of a reefing device to slow the opening. And if that's the case, you're just doing a slider up jump.

87SupraT Nov 8, 2005, 2:35 PM

Re: [DexterBase] Slider Up/Down Idea

Ahh well, unsucessful idea Frown

Frown

. Maybe next time Smile

Smile

.

460 Nov 8, 2005, 3:04 PM

Re: [87SupraT] Slider Up/Down Idea

i think i misinterpreted your original suggestion. You were suggesting using slider up configuration using essentially a low air resistance slider in place of going slider down? Air resistance is not the only key since the friction of the lines with the grommet do slow the process down. A slider with only the outside tapes may present some unknown entanglement issue... the law of unintended consequences.

KMonster Nov 8, 2005, 4:06 PM

Re: [TomAiello] Slider Up/Down Idea

In reply to:

Alternately, you could use a "jock strap" configuration, with the strap joining just the rear risers (and presumably your control lines).

There is a jumper up here (inactive for awhile) who actually made this. His intention was to make something ideal for reefing on about a 4sec delay.

As I recall, he said in practice it didn't actually do much. I can talk to him more about it if anyone is interested though.

TomAiello Nov 8, 2005, 4:12 PM

Re: [KMonster] Slider Up/Down Idea

In reply to:

In reply to:

Alternately, you could use a "jock strap" configuration, with the strap joining just the rear risers (and presumably your control lines).

There is a jumper up here (inactive for awhile) who actually made this. His intention was to make something ideal for reefing on about a 4sec delay.

Tom Manship spent some time playing with one after he saw some guys (I think from Pennsylvania, or Massachusetts, or some such place) out here with one.

If I recall correctly, Tom said he didn't think it did much.

PeteS Nov 8, 2005, 5:29 PM

Re: [87SupraT] Slider Up/Down Idea

Was the canopy a small zp with stainless steel grommets? If so, the canopy/ grommet weight combination might be skewing your observation.

87SupraT Nov 8, 2005, 5:38 PM

Re: [PeteS] Slider Up/Down Idea

In reply to:

Was the canopy a small zp with stainless steel grommets? If so, the canopy/ grommet weight combination might be skewing your observation.

It is an F111 9 cell, and it did have stainless steel grommets in the slider. Aren't the grommets on BASE sliders stainless steel too?

Dale

diablopilot Nov 8, 2005, 5:50 PM

Re: [TomAiello] Slider Up/Down Idea

In reply to:

If you are going to manufacture a slider for this purpose (which you'll have to, because there are no collapsible BASE sliders) why not just make it an "outline" slider (i.e. no fabric in the middle of any kind, just the outside tapes)?

I'd say if you were going to try this, a "spider slider" would be the better idea. (Basicaly an "X" with gromets on the ends.) They are already used on the "Matrix" CRW canopy.