):
June 3rd, 2002 Got my pilot stuck in my left brake lines. completely wrapped one time around. the pilot did not colapse so it caused a lot of drag, turning the system towards a lot of rock.
It was a cliff jump, with a 42' and a five to seven sec. delay. reasonable body position I believe.
velcro rig with a mojo.
long ride to the ground...
June 3rd, 2002 Steve,
could you please explain what exactly is a "pilot chute line over"?
Stay safe out there
Blue Skies and Soft Walls
BASE #689 :D
P.S.: Really, really, really congratulations for your latest and outstanding jump!!!!!!! Welcome back to jumping!!!!!! :o
June 3rd, 2002 I also had the pilot chute stuck in my left brake lines. At the time (1997), I asked CR and BR and they both never heard of it happening before. It was a bridge jump, 4 sec delay with 9' bridle. It's just a freak thing that it happened, but it could occur to anyone because there is usually less than 9' of distance from the apex of your canopy to the rear brake lines. On opening the p/c whipped back and wrapped around and through the brake lines. It resulted in a near full on opposite toggle to get the canopy to fly straight to make the LZ, as the p/c inflated and produced drag on the left side. Video of it is on "FIXED 2!". It happens so rarely that I wouldn't worry about it, but keep it in the back of your mind because you often can't see it if you have a large helmet on.
Jason Bell
BASE428
jbell@vertical-visions.com
June 3rd, 2002 I've had my PC get stuck in the lines a couple of times, no big deal though. I've also had a weird mal with the bridle making a knot around the tailpocket resulting in a hourglass shaped canopy that just barely flew.
All incidents where on terminal jumps and with really hard openings.
Micke N
BASE 268
June 3rd, 2002 I've seen this malfunction three times, twice on video and once in person. In person, it just looked like a weird PC hesitation. We only figured out what had really happened later, watching the video.
The only solution that I've been able to see is only valid when hand held (which is probably the most important time to do avoid this malfunction), and is to toss vigourously upward, to insure that the bridle extracts cleanly and entirely underneath the PC.
On stowed deployments, I have seen PC's perform a complete 180 before reaching bridle extension, which could easily encourage this sort of malfunction, especially with a handled PC. I believe this is mostly dangerous at shallow delays, where the reduced airspeed gives the bridle/PC more time to "wiggle" before pulling taut.
As an interesting side note, you can see very clear video of this malfunction on the climbing video "Masters of Stone II", (see http://www.trailstuff.com/climbing/nar_tnu095.html), available at most major climbing stores in the U.S. In that case, the malfunction results in rather severe injury to a very experienced jumper. Conventional wisdom holds that the malfunction was caused by a non-centerline extended PC pack job (burrito pack). I'm not sure I agree with the conventional wisdom on that, but that's another discussion.
--Tom Aiello
tbaiello@mac.com
P.S. Really, really more congratulations on that jump. The photos are amazing.
June 3rd, 2002 hey, I was looking at some more video, and noticed that sure enough, after a strong pitch from the BOC, the apex of my pilot chute is pointed directly back at me.
this makes me wonder....
I am sure this is a symptom of too strong a toss on the P.C. (and the resulting 90 right is a clear symptom of an orbiting PC brought about by the same - it should seriously be in the textbooks it is so clear). As a skydiver with a lot of jumps, it is so ingrained to wang that fu(ker out to full bridle extension, that I am not sure I'll be able to cure myself of that habit.
does anyone else out there have a similar ingrained throw? have they been able to fix the habit? will a vented PC be enough to help the situation?
It would be nice to minimize off headings and the possibility of a "bridle over" on the PC. Is it even possible to chuck the friggin thing in such a way that it doesn't do a 360 through wads of flailing bridle?
June 3rd, 2002 Disclaimer: After writing this post, I realized it contains lots of unproven techniques, as well as some downright untried ideas. Please don't anyone try any of these things without considering them carefully, and fully accepting the risks of becoming a test jumper.
>I am sure this is a symptom of too strong a toss
>on the P.C. (and the resulting 90 right is a
>clear symptom of an orbiting PC brought about by
>the same - it should seriously be in the
>textbooks it is so clear).
I am not so sure. I think the orbiting can be cause by an over-strong toss. However, I'd prefer to find another way to fix the orbiting, like a vented PC (see below).
However, I think the PC rotation may be a result of the tossing motion--specifically a flicking of the wrist as the PC is released. This might be amenable to solution by changes in the throwing motion.
>As a skydiver with a lot of jumps, it is so ingrained to wang that fu(ker out to full bridle extension, that I am not sure I'll be able to cure myself of that habit.
I wouldn't try to cure yourself of that habit just yet. Getting the PC to full bridle extension seems, to me, to be the logical way to deploy it. A PC thrown too hard may give you orbiting, oscillation and off heading. But a PC dropped in your burble could give you pilot chute in tow, impact and death. I'll take the off heading.
>Does anyone else out there have a similar ingrained throw?
Yep. Lots of us do.
>Have they been able to fix the habit?
Fix may be too strong a word. I've found that by using video and practicing my pitch on the ground, I've been able to reduce the spin I put on the PC. I think the trick is all in the wrist. If you flick your wrist hard (which most of us have learned to do), you tend to impart a spin to the PC bundle. I found that throwing with my arm, rather than wrist, gave me a straighter travel to bridle extension. Of course, with a wingsuit on, and a handled PC (which I prefer for the wingsuit), I still have to flick my wrist (since the wings constrain my arms), and maximize the chance for a "bridle over".
I have not, however, been able to shoot any good free fall deployment video to test these ground based theories.
>Will a vented PC be enough to help the situation?
I think a vented PC will definitely help minimize oscillation from a vigorous toss. At this point, I'd recommend sticking with the hard toss and going to a vented PC, rather than toning down your throw.
>Is it even possible to chuck the friggin thing in such a way that it doesn't do a 360 through wads of flailing bridle?
No idea. But if you figure it out, drop me a line and let me know. I'd love to solve the problem somehow.
The best solution I've come up with (on the ground--not yet in freefall until I harden up a bit) is to rubber band the bridle into the 'S' folds with a loose tailgate rubber band. This appears to control the bridle until after the PC is already ahead of the folds, on the way to extension. If you're going to take this into the air, be aware that you will be a TEST JUMPER, with all the additional incumbent risk that entails.
Also, the first time I started thinking about this was reviewing video of a PNW jumper who frequents this board. Maybe they've come up with a solution that they might share?
--Tom Aiello
tbaiello@mac.com
June 3rd, 2002 thanks, Mr. Aiello!
for clarification I did mean that the hard toss was causing the orbit, not the acrobatic PC.
yeah, I think I'll order me up a vented 42, and use my old one to strain my edemame beans after I cook em.
I definitely agree that it's all in the wrist. I can see it on the video and feel a definite <FLICK> when I toss that thing. make me feel like a man i think.
I would try and just toss using only shoulder action, but knowing me I'd somehow toss it too far forward and under my neck somehow, I am such a spaz.
later
June 3rd, 2002 >thanks, Mr. Aiello!
Mr. Aiello is my Dad. I'll let him know you said thanks, though. ;-)
June 3rd, 2002 >does anyone else out there have a similar
>ingrained throw? have they been able to fix the
>habit? will a vented PC be enough to help the
>situation?
I doubt it can prevent oscillation completely (particularly with a hard BOC toss in low airspeed), but vented PCs definitely dampen oscillation. I've seen it in lots of video, and experienced it in dozens of jumps.
Pretty much, I won't jump an unvented PC any more. Why take the risk, when venting slows oscillation which is a big cause of off-headings, which have a nasty way of killing us? I have a custom vented 42, a CR vented 46, and a CR vented 38 that pretty much make up my arsenal. I have a custom vented 48, but it is missing and I am absolutely, completely convinced that DW ran off with it when I wasn't looking. Gotta watch those Aussies.
Anyway, if you jump stuff where a 180 would be really unpleasant, go to vented PCs. If you are freefalling below 180 feet or so I guess I'd think twice due to potential deployment slowdown. If you are freefalling things less than 180 and a bad off-heading would result in object strike then I hope your "luck bucket" is all filled up as that's some hard ass jumpin'.
Peace,
D-d0g
ddog@wrinko.com
www.wrinko.com
June 3rd, 2002 >Of
>course, with a wingsuit on, and a handled PC
>(which I prefer for the wingsuit)
Dude, you gonna have to explain this setup to me. A couple of us in Sweden have installed the new mod from Birdman where the pocket is actually on the suit itself, sort of back of thigh. works a charm, but is disconcerting, as for the first time in 20 years the hackey is in a different place.
But handholding on a wingsuit jump ? Hmm, what do you do with the bridle ?
<lukas/>
June 4th, 2002 Um. Handled. The pilot chute has an external handle on it (which increases the chance of snagging a loose bit of bridle that flips over the crown).
As opposed to hand held.
--Tom Aiello
tbaiello@mac.com
June 4th, 2002 If you mean that the pc was over the nose or thru lines in the tail it means your brake settings are too deep and your canopy is doing the stall/recovery surge. It happens a lot on underweighted Tandems also..
take care,
space
June 4th, 2002 >Anyway, if you jump stuff where a 180 would be
>really unpleasant, go to vented PCs. If you are
>freefalling below 180 feet or so I guess I'd
>think twice due to potential deployment
>slowdown.
If you are freefalling below 200 feet, you're probably (in my opinion should be) using an upward toss, which will minimize orbiting anyway. The PC tossed straight up will not have the outward momentum that makes it begin to orbit.
I never use vented PC's below 200 feet, for fear of PC inflation slowdown (hesitation).
--Tom Aiello
tbaiello@mac.com
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