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After a 4 second slider up jump at KL tower, i found myself with a canopy flying almost normal but the center cell not working right. i tried two quick control checks with no change. i pointed to the grass landing area and continued to look at the canopy. it looked like a had left a clamp in the canopy and something was stuck at the rear center cell. i was falling fast and barely made the LZ. At 50 feet i was preparing the plf of my life. As i flared for landing, the canopy stalled. I ended up on my heels then my back. I was fine after a hard landing.

Upon inspection, my tail pocket was wrapped around my bridle. This was on a trango with a hybrid LD2. S fold pack job with the tail pocket at the bottom and the bridle exposed at the top of the S. 38 inch vented pilot chute. I used the primary locking stow and no direct slider control. the brake settings were shallow. the slider is the factory large mesh. The opening sequence felt normal. No real explanation that i can figure out other than gremlins.

I would have considered a full canopy collapse to try to fix this, however it did not seem worth risk with the altitude and the way it was flying. Outs at the kl tower were poor other than the grass if the collapse did not work.

if you have this mal, be aware that when you flare half way ish, the canopy will stall fast and put you on your back on landing. that is my experience and hope you dont have this :), If you do, may the luck be with you, i just used a bunch of mine out of my bucket.

I've seen this before with a multi. Is your bridle a multi or is it a standard bridle?

standard

Im pretty sure my multi melted a bunch of holes in my center cell around the tail pocket jumping in twin falls last month.

the multi was designed to prevent center cell stripping at terminal.

not so great for slider down.

Pretty sure something else melted holes in your canopy. haha!

I wonder how fast you were falling compared to normal flight. i wonder how serious this type of malfunction is compared to others maintaining a heading with a line over that can't be cleared.

well, it is hard to quantify. I was the high puller on a 2 way. The other jumper said i cant believe how fast you were descending past me as he was flying the pattern to land. I flew straight to the lz and barely made it. I do remember at about 50' seeing the descent rate and thinking, i am f#%@#d. I could steer ok and it was the main reason i stopped trying to fix it and went for clear landing space. If I had been over a grassy field the whole time, I would have prolly tried a full canopy stall to try and clear it. I talked to a jumper who said the tension in the pilot chute would not clear the mal even in a collapse. Not sure and I hope not to find out :)

My canopy has the same type of small burn hole marks on one side of the tailpocket. The guy I got it from said it was from a multi. I did not really see how before, but now it makes sense.....nothing ripstop tape could not fix.

It would be interesting to resimulate the flight of the canopy with a deliberate malfunction on a skydive (perhaps with a reserve ride too). I wouldn't have thought the descent rate would have been so bad. I had a friend whose top half of the center cell of his canopy tore from nose to tail, held together by the end tapes. He landed it fine (though pretty hard) and was appalled to see what had happened.

I've never had any problems. If all the lines are placed in the sheath during packing, I don't see how there could be. Anyway LARGE canopies can always use the extra extraction help, slider up or down.

"nothing ripstop tape could not fix. "
Ripstop tape is worse than nothing. False sense of security and it damages the material and makes the removal of the affected necessary to be able to sew on it. If you feel the need to screw up your canopy with any type of tape, use gaffer´s tape. It is much stronger (and cheaper I think).
Take care,
space

Purists use patches.

OK, I am busted. I have 4 patches to sew on Thursday
Take care,
space

Very true, but that false sense of security is the warm fuzzy I like...Plus I get tired of people making fun of my ragged out canopy

Ok, how does your tailpocket wrap around your bridle? Am I missing something, I must be, cause I cant picture it. Please explain how this happens, please keep in mind I dont have to think right untill Thursday. Thank You.

How does ripstop tape cause damage?

DZ.com RIP STOP link 1

DZ.com RIP STOP link 2 .
The affected nylon turns translucent and slimy by the time it has reached this stage ( acidic ) .
There is no structural or aerodynamic benefit of applying rip stop tape. It is the psychological equiv of a band-aid on a mosquito bite for a child. It only makes them feel better. Maybe rip stop tape with images of Mickey Mouse and other Disney characters would be more effective.
My peeve is that the new material sticks to the adhesive in the patching sequence distorting the grid of the patch and therefore the patch. Dickin around with talcum powder and or pieces of paper to keep it from adhering to the new material is annoying.
Take care,
space

Thanks for that info. Nice timing seeing I just patched up a small hole with some gaffer tape the other day. Might try get myself organised to get to the rigger's.

BJ

It is more than likely vice versa. The bridle wrapped (half hitched)around the tailpocket and in the transition of forces after, it flipped over.
Take care,
space

Ok, so how does that happen?

How does what happen? be specific and I should be able to explain. The flip over or the initial half hitch?

Sorry, thanks for your patience, the flip over and the bridle wrap. How do they both happen and result in the mal. Thanks.

The flip over: see attachment.
The rest.
the bridle wrap: a. PC extracts canopy. b. canopy starts inflation and creates burble. c. PC and bridle fall back into burble. d. bridle loops and falls over tail pocket in half hitch style. e. PC re-inflates and locks it in.
Take care,
space

Thank you. Thank You.

Sinjin, I have multiple pictures of ur actual mal from the top if you want em let me know. I wont have good internet for a few days but when im home ill send em to u if you pm me an email or somethin

hi, there was a similar mal from moritz in that thread
http://www.basejumper.com/...;;page=unread#unread
it was a wingsuit-issue but probably you can see some connections to your mal.
enclosed a pic from bbc-mirko, showing what happens during a non-wingsuitopening.. it shows what might happend to you if you imagine a moving of the pc to the left, towards center cell and tailpocket...

So is this like a pressurisation wave that flicks the tail (and pocket) up, where it could potentially entangle with the bridle? Do you think an entanglement would therefore be more likely if there was slack in the bridle line, possibly caused by a burble / other source of turbulence?

I wonder if during opening the canopy is in too deep brakes.. even a bit of stalling looks like it would increase the chance for the bridle to entangle with the tailpocket or vice versa

first, we tried to analyse the mal because of an accident in LB while mirko was wingsuiting.
(pretty german, isn´t it.. ) ;-)
he realized the same as moritz, what we identified to be in a special wingsuit-surrounding.
in the follow-up, he viewed some pics from jumps without ws and we came to the conclusion he stated in the pic.
the end of the center cell may move up during inflation and a slack could probably snatch around the tailpocket. not very common at belly-down jumps because of the tension of the bridle upwards with jumper falling straight down, but as you can see, the possibility could be given that the bridle "catches" the tailpocket during opening on belly-down jumps.
I guess, especially during snivel openings (a 4second delay, slider up, as stated)
I see more chances to get that, because the center cell-ending might move more around than with a fast opening.
but that´s just my thoughts from our view on what is happening during opening...
if someone has good pic-sequences from above, the problem might be visible more clearly in the special case from KL.

interesting... at BD last year i was the high puller on a 2-way, so about a 4 second delay SU... flat and stable exit, no tracking.
in the attached pic you can clearly see my tail pocket pretty much right against the bridle just before the nose starts to inflate.

looks like we need to come up with some way to restrict tailpocket from flying up immediately after primary stow release... "tailpocketgate" of sorts.

Let's brainstorm it!

Perhaps, use outer D lines just above their connection to stabilizer as attachment points for tailpocket (using masking tape or rubberband)? (this will require a small loop sewn in the tail bottom right beneath the tailpocket)

i was using shallow brake settings when mine happened FWIW.

heres a little pic just as you were about to touch down, sorry about the quality.

This it what i used to repair my canopy. Its really strong. And doesnt leave any residue. http://www.mcnett.com/...epair-Tape-P139.aspx