Stowing your slider

[billvon 2,998]

As many of you have read, Bryan Burke suspects that a combination of an unstowed slider, sitting at the brake lines, and a non-catseye toggle stow loop, may have been a factor in a recent fatality. A discussion began on the topic on the incidents forum; I have restarted it here since it's more appropriate here.

First off, there are two basic kinds of links. One are Rapide links. (Side note - do NOT use non-Rapide hardware store type links for your canopy! Make sure they say Rapide Maillon on them.) These are metal links that connect your risers to the lines. They have been around forever; the only change is that nowadays people are using smaller sizes. I've seen sizes as small as 3.5 used for mains. Although their working strength seems pretty low (480 lbs for the 3.5 stainless) they very rarely fail when used correctly; 90% of the failures I've heard of occurred when the barrel became loose and unscrewed completely (thus making them very weak) or was overtightened and split.

When the slider comes down the lines during opening, it will usually hit the links. If you have metal links, the impact may be enough to dent the grommet. When the dented grommet is then pulled back up the lines during repack (and when it comes down on the next opening) the sharp edge of the dent may cause the lines to wear more quickly. To prevent this, most people put bumpers on their lines. These can be vinyl tubing (old fashioned) silicon tubing or fabric. This 'buffers' the impact of the slider so dents are avoided.

The buffers also make it a bit harder to pull the slider past the links. As a result, the slider tends to stick there. This is fine for less experienced jumpers on larger canopies. The lines wear a little bit at the point that the slider is flopping around on the bumpers, but it's not too bad.

As wing loading increases, it becomes more important to pull the slider down for three reasons:

1. the extra drag is a bigger issue at higher speeds
2. the slider rattles with a lot more energy at higher speeds, wearing the lines faster
3. the slider prevents the canopy from spreading out - in canopy terms, it remains very cathedraled, and this affects performance.

Primarily for the above three reasons, many people choose to "kill" their sliders with either velcro or drawstrings and pull it past the links and the brakes, so it rests near the bottom of the risers. This usually has to be done before the brakes are unstowed. There is some risk to this; pulling it down may unstow one of your brakes accidentally, and that could lead to an unrecoverable line twist/spin on a highly loaded canopy. It also requires attention during a time that a lot of stuff is going on (deployment, avoidance of nearby canopies.) Finally, there's been at least one fatality from a slider remaining stuck to someone's jumpsuit because they stowed it in a velcro loop on their suit. So be sure you have considered the potential problems before pulling your slider down.

Slinks are the second way to connect your lines to your risers. They don't need bumpers since they're not hard and they're stronger than small metal links, but they also have a few drawbacks. They make it harder to change canopies off a set of risers and they also won't stop a slider at the top of the risers (at least with mini risers.) Often the slider gets stopped by the stowed brake instead. This can be an issue for three reasons:

1. If you have to "panic turn" with the toggles they may not be releaseable if the grommets are directly over them. (Note that you can still turn with risers.)
2. If the slider comes down hard it can release one of the brakes prematurely.
3. You have to deal with the slider somehow; leaving it sitting on the brake line guide rings isn't that safe (as has been suggested by Bryan.)

So both methods of attachement can work, but you have to be aware of the different requirements and hazards of both systems.

[Shark 0]

Did somebody mention bumpers for Slinks previously?

[AggieDave 6]

Yes, I did.

PD makes them now, but their only purpose in life is to keep the slider from going past the links. They're not there to protect anything.

edit: Good post Bill!

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[Shark 0]

Quote

Yes, I did.

PD makes them now, but their only purpose in life is to keep the slider from going past the links. They're not there to protect anything.

edit: Good post Bill!

That's the intended purpose I was looking for. Thanks. Nice post, Bill.

[amir1967 0]

Important topic
I for once without as many jumps as I would like to have ,came across that kind of problem.
When the canopy is fully open and no traffic with two hands on the strings one good pull and the slider collapse and go over the breaks, the problem start when I have to pumpe the breaks in order to un-colapse one or more end cell, which trying to collaps the slider after would take too much time cus now I need two hand for each side .
so unless there is no one up there with me I would just fly it slowly without collapsing it ( mostly because of noise and the flapping which alleady cus it once to go in front of my face ).
So slinks are great but the do takes time to used to and I think if a new jumper wants to use them after student gear it should come with a few minutes of what to do if and where it is different than student gear

AM67

[b1jercat 0]

Ya I got slinks and bumper deals with my new canopy, I used the slinks but left the slider stops off because I have large type risers and the slider stops there. I kill the slider but leave it up, it seems like to much fuss at my level to worry about pulling it down.
blue skies

[SkydiveMonkey 0]

Quote

the problem start when I have to pumpe the breaks in order to un-colapse one or more end cell

So use rear risers

____________________
Say no to subliminal messages

[Watcher 0]

Quote

PD makes them now, but their only purpose in life is to keep the slider from going past the links

Thats not quite accurate. The bumper that PD provides lets the slider gromments come down past the bottom end of the Softlink but keeps the slider above the Toggles. Which if you are not going to stow the slider behind your head is a good thing, because it keeps the slider below the links and off the lines, which is good to keep wear off both the links and the lines.



!!! <----lines
0 <---Soft link
A <--- bumper (cant go past bottom of A)
|| <-- Riser
I <---toggle
|| <--Riser

Jonathan Bartlett
D-24876
AFF-I

[SkyDekker 1,465]

ok, I have a question:

I jump a hornet 190 with rapide links and bumpers. I do collapse my slider but then just leave it there. I do not do any type of performance landing, just straight in approaches.

Is it possible to pull down the slider and just leave it behind you head? Or is it really much more recommended to have some sort of "slider restraining device"?

Justin

[Watcher 0]

I did that for 500 jumps, it works just fine, I only expirenced problems with Higher speed approaches where it got to a point where I did want to further restrain it.

The act of simply collapsing and putting it behind your head is perfectly fine (and recommend) you dont have to do High speed approaches. If you let the chest strap out to it most loose then it spreads the risers out and keeps the slider down.

--

Jonathan Bartlett
D-24876
AFF-I

[Hooknswoop 19]

Quote

Ya I got slinks and bumper deals with my new canopy, I used the slinks but left the slider stops off because I have large type risers and the slider stops there.

The bumpers don't fit on large risers.

Hook

[billvon 2,998]

>Is it possible to pull down the slider and just leave it behind you
> head? Or is it really much more recommended to have some sort
> of "slider restraining device"?

"slider restraining device?" Like a velcro loop on your jumpsuit? I strongly recommend _against_ them; there's been one fatality where the guy tried to cut away after he put himself into line twist and the canopy remained attached to his jumpsuit.

If you collapse the slider and pull it all the way down it usually stays out of the way, and there's not too much trouble it can cause back there.

[SkyDekker 1,465]

thanks for the answers, will do this weekend.

[dreamsville 0]

So, if the slider is down past the brakes, obviously the toggles will be over and outside of the rear of the slider (otherwise the toggles couldn't return to full flight all the way up to the rings). My only concern about this is if I have my top-mount Hanson camera helmet on (I may be getting a side mount), maybe I've got the back of the camera or the back of the helmet with those clamp closings rubbing against the slider as I check for traffic. Maybe it's a personal thing, but in that mode I am more comfortable leaving the slider up and not worrying so much about performance. Since the line wear at the slink point seems to be the remaining issue, I guess that's all right if it's done on a limited basis.
|

I don't drink during the day, so I don't know what it is about this airline. I keep falling out the door of the plane.

Harry, FB #4143

[TALONSKY 0]

For stowing the slider, I have had an extra piece of webbing sewn on the bottom of my front risers about two inchs from the bottom. the webbing is about 1/4 to 3/8" wide and doubled over. It is sewn at an angle may be 30°. So the slider can be pushed past it and then it can not get back up without some help. I like this kind of stow because the slider is not hooked to the pilot and it keeps it all the way down.
Kirk

[MrHixxx 0]

One quick note on slider bumpers. It is a good idea to run a loop of tack cord around the bumper so it stays on the link. I have seen a malfunction were a worn bumper slid up the lines and fouled the slider from coming down.

I also use a slider stow on my front risers. It works great and everything still goes away when you chop it.

-Hixxx

death,as men call him, ends what they call men
-but beauty is more now than dying’s when

[skydiverek 63]

Quote

One quick note on slider bumpers. It is a good idea to run a loop of tack cord around the bumper so it stays on the link. I have seen a malfunction were a worn bumper slid up the lines and fouled the slider from coming down.

That's why I think it is mandatory to do that on reserve with slider bumpers...

[MrHixxx 0]

Anytime I pack a reserve with bumpers, I tack them... Bumpers on mains get considerably more wear and exposure though, so I think it is equally important to tack them. Unless of course you like to supplement my income...
-Hixxx

death,as men call him, ends what they call men
-but beauty is more now than dying’s when

[JamesNahikian 0]

Every set of risers with bumpers that I've owned did have the bumpers tacked. You mean this isn't standard practice?

D. James Nahikian
CHICAGO

[MrHixxx 0]

Not that I have seen. I guess it all depends on the diligence of your rigger in assessing the risk. We have a lot of the urethane bumpers in this area. They are quite secure until they start getting chunks taken out of them by the slider. However, I have seen clear plastic bumpers too which I would tack from the getgo.

-Hixxx

death,as men call him, ends what they call men
-but beauty is more now than dying’s when

[masher 1]

Quote

For stowing the slider, I have had an extra piece of webbing sewn on the bottom of my front risers about two inchs from the bottom.

I've heard of this before, and it seems like a good idea to me. Would you be able to post some pics of them?


Cheers

Matthew

--
Arching is overrated - Marlies

[hookitt 1]

Here's a drawing of the slider catch. I've used this type of catch for many years. It's attached about 1 inch up from the confluence.

Credit for to drawing goes to another dz.comer.

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[masher 1]

Cool.

Thats pretty much what I invisenged (sp?). How do you keep it stuck out to keep the slider down? Do you double the material over to force it out?

--
Arching is overrated - Marlies

[hookitt 1]

The material is 1 inch type 4

Double it over and Sew a bartack or Tight ZigZag stitch down each side. Then Sew it onto the riser.

Heres a quick Diagram

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[RichM 0]

How long is the original piece of 1 inch type 4 before you fold it in half?

Rich M