Line Dump

[Hooknswoop 19]

If anyone has pictures or video of line dump, would you post them? By line dump I mean the canopy has come out of the deployment bag with the line still slack.

Closest I've seen to this is a rubber band breaking (twice) on a tandem, but it wasn't a locking stow and din't impact the opening. I didn't even know it had happened until watching the video.

Hook

[skygod7777 0]

i have video of my dad having line dump like you want(it was on a tandem too), but i don't have any way of posting a video. i will try and dig up the tape and see if i can get a still off of it.

lager

[Zennie 0]

Heh. If you wanna see Bill get spun up, just use the phrase "line dump" to describe what you're saying. His take is that there is no such thing as "line dump". Rather, what you have is an out of sequence deployment.

I tend to agree (for whatever that's worth). My guess is that "line dump" came to be because the phrase gives more of a visual of what's going on.

- Z
"Always be yourself... unless you suck." - Joss Whedon

[AFFI 0]

I was oing a search, looking for the standard definition of "Line Dump".
The definition in the initial post is what I thought the definition was.

Out of sequence to me, and the entire community in my neck of the woods is referring to a type of Horseshoe, where the container opens prior to the PC being deployed; it is still in the pouch. The deployment sequence is not in order (Step1. Deploy PC - Step 2. Container Opens - Step3, Canopy Opens). Step 2 takes place before Step 1...

Mykel AFF-I10
Skydiving Priorities: 1) Open Canopy. 2) Land Safely. 3) Don’t hurt anyone. 4) Repeat…

[AFFI 0]

If you still have, or ever posted that video I would love to see it.

Mykel AFF-I10
Skydiving Priorities: 1) Open Canopy. 2) Land Safely. 3) Don’t hurt anyone. 4) Repeat…

[peek 21]

Quote

If anyone has pictures or video of line dump, would you post them? By line dump I mean the canopy has come out of the deployment bag with the lines still slack.
Hook

I like how you're thinkin' buddy.

With yet another round of talks in another thread where people are claiming the likelihood of "line dump", I was about to request video myself.

I have been thinking of making the request for a long time now actually. I've even thought of offering a bounty, because I don't think I will ever have to pay.

The closest I have seen was a long time ago of a Tandem Vector with lines falling off without tension, but no canopy even close to being out of the bag.

(I'm tired of hearing otherwise knowledgeable skydivers and riggers telling people to be sure to stow their lines tightly or they may have "line dump".)

[AFFI 0]

One of my mentors, happens to be a rigger as well as being a top notch instructor has always told me that “real” line dump will kill ya!

Mykel AFF-I10
Skydiving Priorities: 1) Open Canopy. 2) Land Safely. 3) Don’t hurt anyone. 4) Repeat…

[koppel 5]

cant help you with video of what you have asked for in your original post.

I would like to mention that in my part of the world 'Line Dump' would be generally referring to a deployment sequence where the lines have released from the stows in an order not exactly reversed from how they were made. The canopy would generally be considered to still be in the bag until line stretch.

Line dump in that consideration would still be a major issue as the bag has slowed down to a greater degree due to no tension on the lines and therefore the opening is that much more sudden and with more drastic consequences.

I find it hard to imagine a situation where the canopy can come out of the bag before the lines have reached line stretch except possibly where the locking stows and all normal stows are so loose as to allow the canopy to egress the bag early. If someone was jumping equipment in that state then personally they probably will get whats they deserve C'mon folks lets look after our gear and ourselves.

I like my canopy...


...it lets me down.

[jojo0815 0]

I agree, a complete line dump would be really bad but very unlikely at any rate. I think what most people refer to as line dump is commonly also known as "body position" :).

deploying a single or even multiple stows out of sequence can cause tension knots or a hard opening due to excessive snatch force at linestretch.
if you are using a freestow bag with too little tension on the mouth of the bag both of those scenarios are pretty likely.

[rushboy 0]

Forgive me for what may be an uninformed opinion, but I was once told that, aside from symmetry, there are only two things that affect the deployment of a well designed canopy...the slider and the locking stows. I have been operating on that premise for some time with much success. Based on that, I have never seen a TRUE line-dump. I am a rigger, but I am also a packer, and I have demonstrated this theory to my clients many times. I think line dump is very rare, and a result of poor maintenance. Reserves are mostly deployed with only two locking stows and the excess line stowed in a small pocket. Even if all the lines are stripped from the bag (barring knots and other random events), the canopy should deploy properly with the locking stows intact and the slider at the stops. Body position (not including "high-speed" deployments) shouldn't affect the force of the deployment. Any opinions?

If you are not living on the edge, you are taking up too much space.

[phoenixlpr 0]

Quote

Reserves are mostly deployed with only two locking stows and the excess line stowed in a small pocket. Even if all the lines are stripped from the bag (barring knots and other random events), the canopy should deploy properly with the locking stows intact and the slider at the stops. Body position (not including "high-speed" deployments) shouldn't affect the force of the deployment. Any opinions?

Line stows seems to be the safest way for our monkey packers.

AFAIK it takes more than 90 minutes to pack a reserve. How can you expect the same precision and responsibility for a 10 minute pack job?

[jheadley 0]

This isn't exactly what you're looking for but it's still a good picture and it makes you think.

[Hooknswoop 19]

Looks like standard rubber bands on a tandem D-bag. Do you know what rubber bands are on there? Even then, the canopy is still in the bag and the locking stows look fine. How was the opening?

I am still looking for video of a canopy out of the d-bag before line stretch. I would constantly hear that 'line dump' "caused my hard opening", but I have never seen video of a modern canopy out of the bag before line stretch or what I would call 'bag strip'. I believe that bag strip would cause a catostrophically hard opening with canopy damage and/or injury to the jumper.

I think that 99% of hard openings are caused by not keeping the slider against the slider stops during packing and pulling after a diving, not flat, track.

Derek

[rushboy 0]

I agree with your opinion on the slider. I had a chance to "sit down" with Brian G. a while back when he was doing a course up here in Canada, and that was his view also (sorry if I have over-simplified your thoughts on the subject Brian). BTW...I got your msg Mjosparky...thanks for the support.

If you are not living on the edge, you are taking up too much space.

[riggerrob 643]

AFAIK it takes more than 90 minutes to pack a reserve. How can you expect the same precision and responsibility for a 10 minute pack job?

[phoenixlpr 0]

Quote

Correct!
But if you can convince packers to focus on two or three points, you can prevent 90 percent of hard openings: slider hard up against the canopy, balanced locking stows, three fingers worth of line outboard of rubber bands, rubber bands tight, etc.

You have almost got my message. He has stated that line stows are not so important. I think they are. They seem to be quite foul proof for us , lousy packers...

[Stumpy 284]

I used to pack for a couple of people who didn't want me to use ANY line stows except the locking stows. the rest of the line was just figure 8 in the pack tray. They got some of the best openings i have seen.
(Canopies were a stilletto and an original sabre)
I don't believe that the rest of the line stows make much difference apart from keeping things tidy. Like others have said, focus on the slider and the locking stows.

Never try to eat more than you can lift

[phoenixlpr 0]

Quote

I don't believe that the rest of the line stows make much difference apart from keeping things tidy.

They should be tidy.

There could be tension knots e.g. if they are not tidy.

[jheadley 0]

I admit I've done that too a few times and had great openings from it, but I definitely would never do it again. With all that loose line, it'd be easy for it to wrap around a flap and cause an entanglement. At least with freebags the pouch contains it.

[billbooth 10]

Quote

I admit I've done that too a few times and had great openings from it, but I definitely would never do it again. With all that loose line, it'd be easy for it to wrap around a flap and cause an entanglement. At least with freebags the pouch contains it.

Ditto! Always stow all but the last 12-18" of your lines.

[sundevil777 102]

Quote

This isn't exactly what you're looking for but it's still a good picture and it makes you think.

That is exactly why I think locking stow bands should NOT be easy to break.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[riggerrob 643]

That is exactly why I think locking stow bands should NOT be easy to break.

[riggerrob 643]

Circa 1980, mjosparky learned that free-stowing lines was a bad idea.
CSPA even published Technical Bulletins discouraging free-stowing.
Hint: Para-Flite gave away hundreds of main deployment bags during the 1980s.

But skydivers are a stubborn lot, so somebody re-learned the lesson last year ... knotting suspension lines around a side flap.

Ho hum!
Same malfunction ... different year.

[KellyF 16]

Quote

I am still looking for video of a canopy out of the d-bag before line stretch. I would constantly hear that 'line dump' "caused my hard opening", but I have never seen video of a modern canopy out of the bag before line stretch or what I would call 'bag strip'. I believe that bag strip would cause a catostrophically hard opening with canopy damage and/or injury to the jumper.

I've seen video of a tandem canopy that was packed with broken locking stows that were "half-hitched" (basically tied around the lines) to allow them to be used. On deployment, they ALL came undone, and the canopy came out of the bag maybe 3 feet out of the container. All of the rest of the lines remained stowed on the bag and came unstowed in the normal manner. The opening was perfectly fine! I think the canopy was an Icarus 360, but I'm not 100% certain on that.

Standard "line dump" typically won't cause a catastrophically hard opening. It may cause a bit higher snatch force, but for things to get really nasty, the canopy has to get out of the bag, and for this to happen, the locking stows will generally need to break. During the initial moment of the pilot chute lifting the bag out of the container (like the pic posted earlier), the canopy is trying to fall out of the bag. This puts more pressure on the locking stows and holds the line bites tighter. If the locking rubber bands remain intact, the only way those line stows are going to com undone is by getting pulled out by the remaining lines between them and the risers. The only way thats going to happen is for that amount on line to get pulled taught. You may hear some people say something along the lines of "the weight of the dumped lines will pull the locking stows out", well, that can only hold water if those lines are straight, meaning the bag is at the end of the lines Look at it this way: you have a pile of rope or better yet, chain, on the floor with a scale attached to one end. When the scale is close to the floor, it barely registers any weight, right? But as you lift the scale higher, it registers more weight because it's suspending more of the rope/chain. What the scale is seeing is exactly what the last locking stow (the one before the standard line stows) is seeing in a case of line dump (not bag strip).

Wow, I hope that helps some people- I need to go build rigs

VSE on Facebook

[sundevil777 102]

Quote

That is exactly why I think locking stow bands should NOT be easy to break.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Can we agree on MIL SPEC rubber bands that are rated for 40 pounds?