Slider up line-overs?

[baseninja]

I hate to ask a question that really has no good answer, but:

Are slider up line overs more likely with large mesh, small mesh, or a sail slider?

Does anyone worry about line-overs in skydiving? Of course the consequences are worse, but I don't think I've ever heard or seen a line over while I was at a dz. (ok, bands for lines, d-bags, etc…)

If you take care to reef your lines so that the control lines are on top of the Ds, which are on top of the Cs, etc... And yes, lines are flying around everywhere on deployment. But with a slider, it “should” reef the lines satisfactorily... ?

It seems that upon deployment, the lines feed out of the tail pocket, and then there is 200ish pounds getting pulled faster downwards, and a LOT of drag trying to pull upwards, relative. How do lines, admittedly long lines in hectic openings, get past a reefing system and at least on method of slider control? What is the advantage of masking the bands, when there are sliders with bands and bites for the tailgate friendly lines? Or what if you just took small bands at the rear corners of the slider, and a light bite of the control lines?

With indirect control (the primary stow bite): All the lines should be fed out of the tail pocket and lots of tension should be there, from the deceleration/acceleration of the still slider up canopy and jumper. The slider should be holding all the lines together at that point, and I can’t visualize how a control line could sneak up and around the front of the canopy before complete inflation. And yes I know it is possible.

With direct control (banding the slider to the C lines): The slider is again held up, reefing the lines towards the center of the canopy, and again away from the ends of the canopy, “theoretically” keeping the long control lines from making it up and over the building canopy. Once the slider breaks away from the direct control bands, it would seem that the canopy is building and widening, making it even more difficult to get a line over…

I don’t know everything about BASE, yet, but I know several jumpers that I have a lot of respect for have experienced a slider up line-over in BASE. But the more I think about it, I don’t understand the dynamics of how a line can get over with a slider locked up there and a primary stow taken…

Makes you want to get a hook knife, huh?

[SBCmac]

I’m by no means addressing all your points... Good points by the way, I've had the same thoughts run through my head ...

Anyway, I thought you’d find this thread on dropzone.com interesting (You’ve probably already read it by now…):

http://www.dropzone.com/cgi-bin/foru...=unread#unread

I guess, as far as what I'm gathering from the above forum, the goal is to encourage nose first inflation no matter if it's a slider on or off jump by using some type of control line control method (e.g. tailgate or masking tape). Slider on or off, tail first inflation increases the chance of line over. I think as people experiment with taping the control lines on slider up jumps, we'll shortly discover whether or not control lines are sneaking around the nose just before line stretch (because of tail first inflation). So I guess I'm thinking we'll find the solution before we'll find the answer... My answer right now is to carry a hook knife and stay tuned to people’s discoveries with taping the control lines on slider up jumps...

...

SBCmac

[Tom Aiello]

...I don't think I've ever heard or seen a line over while I was at a dz. (ok, bands for lines, d-bags, etc…)

I haven't either, but I don't spend much time at the DZ. If you do a search on the DZ.com incidents forum, you'll see that there are numerous line over incidents reported there, including at least one on a reserve.

It seems that upon deployment, the lines feed out of the tail pocket, and then there is 200ish pounds getting pulled faster downwards, and a LOT of drag trying to pull upwards, relative. How do lines, admittedly long lines in hectic openings, get past a reefing system and at least on method of slider control?

Any slider control method can fail. Rubber bands do break, things slip loose early, etc. I'd guess that most of the cases where we've seen line overs have involved some kind of failure in the reefing systems.

What is the advantage of masking the bands, when there are sliders with bands and bites for the tailgate friendly lines?

At least one manufacturer discontinued the use of the slider band system because they felt it compromised heading performance. When you take a bight of the control lines, you shorten them (not necessarily perfectly symmetrically), which alters the trim of the canopy during the opening sequence. I assume that some canopies are designed to take this into account, but I know that some are not.

Or what if you just took small bands at the rear corners of the slider, and a light bite of the control lines?

Can you explain more? Would the bites be above or below the grommets? I'm wondering about potential entanglement or tension knots involving the control lines and the grommets.

I can’t visualize how a control line could sneak up and around the front of the canopy before complete inflation.

Me either. But I do suspect that some kind of failure in the reefing system may play a role.

Once the slider breaks away from the direct control bands, it would seem that the canopy is building and widening, making it even more difficult to get a line over…

It seems that the direct control would have slightly more chance of releasing prematurely, because (a) the lines go straight down from the slider, which means the slider _is_ under tension from it's own weight (as opposed to the indirect control method), and (b) the rubber band used is generally smaller.

Makes you want to get a hook knife, huh?

On all my rigs...