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Hi!!!

Some people are using tailgate on jumps with slider up!!
Any one knows how this works?

Thanks
Paula

I use a slider tailgate. A sencond tailgate is sewn in the middle of the trailing edge of the slider.

If you do so make sure the slider is fine mesh.

How much does it effect the opening time?

Small mesh slider, normal tailgate.

K

And if you use a large-mesh slider, you can use masking tape. It's what I've been doing. It kinda interferes with a possible slidergate, but I wasn't using that one anyway.

http://www.dropzone.com/...p;sb=score&mh=25

I was talking to Tom about it. I don't think it affects the time although the openings seem more "staged" probably due to the fact that the slider tailgate acts as a "direct slider control" but without the side effects of it because the tailgate is right in the center of the trailing edge and the lines are not shortenen.

some people note harder openings with direct control or slidergates..........

thoughts?

I've done four base-rig terminal skydives. Two with slidergate and two without slidergate but with masking tape. Everything else the same. I'd say the ones without the slidergate were harder, but not considerably. Might not be enough statistics anyway.

All four were with indirect slider control, no direct control. Large-mesh slider.

I did not use the words softer or harder. To me it seems more "staged" but it could be a placebo effect.

I think Tom was experimenting with this set up as well so he can add few things.

I've used a variety of methods, primarily tape and the trailing edge slider-gate, for around 100 slider up short delays (3-4). I've noticed a few openings that might have been slight hesitations of slider descent. In general, I do feel like it stages things a bit more (I can notice a distinct shift in most of the openings, which appears to be right when the gate opens and the slider begins to descend). This doesn't usually appear to be a slow down (or speed up) of the opening (although note that in a few--maybe 5 out of 100--cases it did seem to slow things down).

At any rate, at this point I've got no real scientific analysis or conclusions. My personal conclusion is that I will continue using either method (tape or trailing edge gate) interchangeably, and will use such control on virtually all of my slider up jumps. I might remove the gate if I was smoking it into the basement (by which I mean a slight slider hesitation would result in injury).

I know that's no real help, but so far all I've got is personal impressions.

This thread got me wondering:
Who originally thought of the idea of attaching a tailgate on the trailing edge of the slider?

The first person I heard the idea from was Mark Hewitt.
It was spring 1999 and a small group of staff/BASE jumpers were hanging out one night at a DZ. Mark and I got to talking about BASE gear and the innovations and improvements over the years. So we got to the subject of lineovers, line release mod, and tailgate. So naturally we started thinking about slider-up lineovers, and how it sure would be nice if there was some way to..............
Then out of nowhere Mark says, How about just putting a tailgate on the trailing edge of your slider?

Did someone somewhere else think of it before then.
Its cool to see people doing it now.

Hello Jonny, Nick,

Can you explain the "side-effects" on direct-control??

I really can't see any advantage of useing a tail-gate instead of direct-control.

Thanks
t.

If youre comparing the use of tailgate (on the inner C line or the slider) with the use of direct control for the slider, the differences are such that each is very specific to its purpose.

The purpose of the tailgate is to inhibit tail-first inflation and to reef the steering lines during the initial stages of deployment. I think its safe to say that the tailgate has proven itself to be the best method of line-over prevention in the slider off/down environment. Even still, there are a few cases where a line-over has still occurred.

The purpose of direct slider control is to hold the slider up in its most effective reefing position (the top of the lines) until the bottom skin starts to inflate, which is the stage when the lines spread and force the slider down.

Here are three benefits of direct slider control.
1. Since the slider cannot be pulled down by gravity during or just after line-stretch, it greatly reduces the chance of getting cracked on opening by making sure the slider is in place long enough to do its job.

2. The purpose of a slider is to reef all the lines (in the center) during inflation. So when the steering lines are routed through the guide-rings and grommets, the slider reefs them as well. That function in itself helps to prevent a line-over by somewhat controlling the steering lines. So direct slider control helps the slider do its job better. The longer the slider stays at the top of the lines until the start of inflation, the better it can reef the lines, and the better it can help to prevent a line-over.

However, the chances of getting a line-over while using a slider (no tailgate) are much greater than using a tailgate with no slider. The idea behind using a tailgate on (or with) a slider is to have a similar reliability as the tailgate in a slider-down/off set up.

3. Direct slider control may also help reduce the chance of a tension knot. Theoretically, I would think the more the slider grommets can move up or down the lines during line-stretch and/or any snivel, the greater the chance of the slider being a contributing factor to a tension knot.


Some people call the main stow, indirect slider control.
The purpose of the main-stow is to stage the opening somewhat. It holds all the lines together at the top until full line stretch. This helps keep the canopy together at the wind channel before and during line-stretch. Theoretically, this can help reduce the chance of a tension knot by not allowing the lines to move around as much individually.

Another benefit of the main-stow is that it prevents the slider from sliding down the lines until the main-stow is released. This happens at full line-stretch. The slider can still move down a bit just as the main-stow is released and continue down until the bottom skin starts to inflate.

I use a main-stow on every jump (except when using a direct bag or sleeve).

I use direct slider control (and the main-stow) on all moderate to higher airspeed slider-up jumps.

I think that using direct slider control is the best way to keep your slider from coming down early, and that such a function becomes more and more important the higher the airspeed becomes.

I also think using tailgates with sliders is still in a proving phase (test phase) for many jumpers. The use of masking tape with a slider-up pack job to momentarily reef the steering lines seems to be very popular these days. I like the masking tape trick for slider-up jumps as well, though I dont always do it. I still use micro-reefing techniques during my pack job to inhibit tail-first inflation.

Hope this helps

Thanks for the detailed reply.

I understand all you wrote and I think the same way and at some points you ensured my thoughts.

The use of the tail-gate at no-slider jumps was quite clear, and you helped me understand it better.

The thoughts below only apply to slider-ups:


Same for me and many others here: Whenever I put the slider up, it gets directly-controlled, always.

I am still puzzled by Nicks "side-effects" of useing the direct-control. (By side-effects I understand some disadvantages/draw-backs)

First I thought that the tail-gate on slider-ups inhibit tail-first inflation, I don't think this is that effective (again only at slider-ups).

So, correct me if I'm wrong, I still don't see any point of useing tail-gate with a slider directly controlled except you want a backup-double-controllines-control.

Thanks again for the explanations
t.