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I recently saw a post about tension knots that had alot of info, but all of the discussion was about slider UP tension knots.

Here is a video of two different friends having slider down tension knots:
(unfortunately none of them had a camera so you cant see much)

https://vimeo.com/74722519

On the first jump the object is 80m (260ft) and the jumper does not have enough time to clear it, resulting in a very heave pelvis fracture. (didn't get up from the bed for about two months). The marks on the lines were not that obvious so we are not positive exactly where the knot was created.
On the second jump the lines had serious burns, and it was obvious that the knot was in the C,D and brake lines a bit above the cascade.

Both jumpers were jumping a Troll 285, and the gear did not have more than 60 jumps at the time. Both pack very carefully, neatly and use a tailgate.

My friends an I were under the impression that slider down tension knots are non existing in modern BASE gear.Obviously they are not!

So can anyone suggest what the cause of this might have been?
If by accident you put more lines in the tailgate... could that create any problems of this sort?
Are slider down tension knots as common as slider up?
What is the best thing one should do in this case, given the limited altitude of a slider down jump?
Does anyone have more videos of slider down tension knots?

Thanks!

Hi,
If there is a problem it means that the packing job is not so good... when you put the lines into the TailGate it is very important to start from the rear risers with clear lines (brakes + CD cascade / black ones). If you put the lines directly in TG from top you are sure to make a entanglement with other lines!
Packing basics: symetry, tension, clear, and control many times

I never seen in live a tension knot but 2 times to friends lines blocked in the velcro of TailPocket (SU & SD), the canopy was not flying well but straight, solution is to pull hard "pump" on brakes to free the lines.

Take care

I think you mean to quickly stall the canopy to create slack in the lines to clear the tension knot. 'Merica!

yes

I know you cant take my word for it but do! they are very neat! after the second incident Tom Aiello supervised both their pack jobs (and they were doing exactly the same thing that they always do) and he couldn't see anything wrong with their pack job.

so you are saying that its possible to have a tension knot and be flying straight ??

Having watched the pack jobs of the jumpers in question, I don't think that packing was the issue. Both had good pack jobs, and had properly cleared the tailgate.

I believe that both of them learned to pack at the Pressurized course, which means that at a minimum both the Pressurized instructors and myself have supervised and checked their pack jobs.

Have you considered that the individual lines connected to the links may have twist in them? Follow each line from the connector link to the cascade to check for line twists. It's no different than taking the twists out of your brake lines. Don't trust the guy that hooked up your links. I've received many rigs, both from manufacturers and individual owners, where the individual lines have as many as 7-8 twists in them. I've unwound twists off of skydiving reserves with the same issue. This could definately cause a tension knot.

I didn't write that (see other post "another tension knot" too), just for the 2 cases I saw of one line catch in the velcro of TP it was flying straight but not well. But with a "real" tension knot on cascade CD the canopy will go into spine. If you want that people help you in understanding perhaps give all the good informations before... and I would have said nothing about packing job. Thx.

I saw that on a BASE canopy but not a Troll, worrying!

Do you know what type of line they were?

Dacron. Both canopies were Trolls.

Before i even get into base i did a small research on tension knots !
so what is a tension knot ? i guess i will agree with the guy saying < it's a knot with tension >
Tensions can come from having wet lines or even packing badly, and sometimes we just dont know how they happen...well we do know but we don't want to admit our fault !
ask yourself why did it happen.go back and search ! an oversized PC can cause a malfunction( tension knot or lineover,a larger PC is more likely to strip the center cell and/or deform the freepacked canopy as it extracts.) untwisted brake lines can also lead to such event,did your mates untwist the brake lines or even have you checked the C /D lines for twists before they were hooked up on the riser ? do you use a tailgate , if yes ,are you sure that the right lines are inside and without twists(bottom to top ) ?! do you jump a rig that has previously been wet ?

if your not already doing it... lay your canopy on its side. when its on its left side... pick up your furthest most right lines. (right steering and the line far most right on the rear riser and the line far most right on the front riser) walk them up to make sure they are in order.

next... grab all the steering lines and flake them out pulling back against the risers. make sure the tail section you are holding has the steering line attachment points in order and walk the line back to the risers untwisting the line.

i do this by squeezing tight on the steering line after the cascading lines with my fingers and walking it up to the risers. set the breaks and shaaazame... no tension knots in the steering lines.

repeat with the other side of the canopy.

personally i had 0 events of a tension knot but thats just me packing neatly and rubbing my lines with silicone oil (non petruleum ).



concerning your vimeo link i see bad body positions in both jumpers and a slight crosswind on the first object. certainly you can get away with these for a handful amount of jumps but when the luck jar gets empty you ll get hurt even if your experience jar is almost full .

just my 2cents .

Another one.

http://youtu.be/Oa4_MvnB5f0

Ok so what is going on? I captured the canopy shot and looking at the picture it looks like the upper-inside control line is caught up in there somewhere above the cascade on the c and d lines on the "black" cell to the right of the center cell. It looks like there is slack on the inside upper control line but the tail of the canopy corresponding with that control line is being pulled down and the rest of the tail to the right isn't as constrained...

After looking at the picture and messing around with the contrast and saturation and and all that stuff I can see the inside-upper control line is "attached" just above or right at the c and d line cascade point. It looks like the upper control line is attached to the c line because there is more distortion on the canopy at the line attachment point.

I wonder if she was using a tailgate and the control line got hung in it somehow..?

She was using tape.

Ah-ha! Clears that up... Where you there? Did you all find out what it was?

I was wondering why my video got so many views! I am famous. Alright, so I realized, when I said "What is going on?", that my canopy was not going to be able to fly to the LZ. I decided to land it as quickly and "safely" as I could and I chose the nearest landing area. I didn't sustain any injuries other than a small scratch on my palm. I figured that with the amount of pressure that I needed on my left side that I would probably stall out the canopy if I continued to try to fly it. If I had the same malfunction I would do the same thing.

Did you ever figure out what happened?

I repacked the same way and then jumped off Mary's gash about an hour later and everything worked fine. I have only been using tape as my tailgate and I have been finding remnants on my lines after landing, so I am not sure. I pack very neatly so I doubt it was packing. I also make sure that my brake lines are clear, I throw them to the sides when I am packing and then run the lines down looking for twists, like a skydiving rig. I have been talking to people in the sport and the only thing that I might have done wrong, was taping my tailgate far up the lines and not where the tailgate attachment point is. I will no longer use tape and will use a regular tailgate from now on. My canopy is a vented troll 225 with about 40 jumps on it. I feel very lucky that this happened on this particular cliff which had the option of landing on the talus.

 I have been talking to people and they have asked me why I didn't try to "clear" my mal by pumping the side with the issue. As soon as I felt the lack of tension on my right side and then realized how much tension was needed on my left to steer at all, I stopped putting any input on my affected toggle. At the end of the video you see me slam right, that is because I flared at the end and I believe that it mad the tension knot worse. I don't know what the other 2 guys did on their malfunctions, I would like to know if they tried to "clear" it by pulling down on the affected toggle. If you are interested in my turkey travels video, at the end, there is the rear footage. I Was being super cool with 2 cameras on this trip.

http://youtu.be/xBHq7o0AuYE

FWIW I think you made the right call. I had a tension knot that spun up like a bitch when I tried to turn. I was able to stable it before I landed. Pure luck I think.

+1. This was an incredibly good response, and a great job of turning a potentially fatal situation into a minor scrape.