Oct 14, 2008, 8:10 AM
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A friend wants to know if it is ok to strap to another person during a downplane. I think not myself. Maybe an ankle strap to hang to. Is there any gear store for CRW?
Yeah dragon2, that was my first instinct. If you can't hold the ankles with your hands then maybe it's not for you kind of thing. Still, and i repeat, this is not for me, my buddy is wanting to look at some gear along those lines. I've done downplanes and triple downplanes and love it to no end but DO NOT TIE ME UP.... Well, maybe for actual canopy work. Anyway, some links and pics would be cool.
You pic is scary, because they both have both their hands on their toggles. Meaning they are not holding deadman cutaways. They must truely be strapped together.
I understand there is a certain leg hold, that will leave hands of both people free for canopy control. I tried a similar one with my instructor while i was still holding on and it seems that i didnt have to hold his legs. There is a video somewhere where two guys with this leg hold turn their canopies 360.
Does anybody have a clear photo of the parabatic grip? I can't make out exactly what is going on in the YouTube videos. I've had some success with other grips, but the legs-only style has never worked for me.
That leg grip doesn't work for the 2 pics I posted which is why they used straps.
The three way down plane can be. Check out the photos I posted here.
The second photo is even easier - it requires neither a parabatics grip nor straps, just a plane old side by side with one jumpers feet in the bottom jumpers lines. I can dig out some photos of that if you want.
It's called the Parabatic grip. You can see more at: http://www.youtube.com/watch?v=F1VMUZw8W0A
John
Isn't this the same grip that can lock you up?
I've been in a couple of DPs where at break off we were locked in. We had to reach back with our hands and take the tension off it to release. Fortunately, we were a little off target and had to break high each time. Ever since then, I check the "feel" of any style leg grip to make sure it will release, especially if we were smoking it low.
On the death straps for a tri-by-side, I've used them before but it was years ago. Not a 3 ring, but it was so long ago I only remember that we tested them repeatedly for release reliability before using them. We finally gave up using them after we figured out a reliable leg grip.
Here was our recipe for a solid tri by side. Start in a side by side. Center guy docks on the bottom and uses brakes to come up. Center guy takes and keeps a harness grip on each man for the duration. At this point, the center guy gets as high over the leg grip as he can (gotta come down on it, not from behind it). He then wraps his legs over and around the side by side leg lock and sets his ankles underneath. At this point, split it out into a tri by side. We flew a few from 7K all the way down to 40' with little strain.
Whatever your grip and technique, practice practice practice and then anticipate that is will still go wrong in the air the first few times, so play high and break it off early.
Preferably, you should practice your downplane technique in the middle of the packing area. If your worried about getting dirty, you can get one of those plastic mats from the children's game Twister. That way, even if it doesn't work in the air, you've already entertained everyone. :-)
With regards to death straps, I figure much better skydivers than myself have experimented with them and concluded that they just aren't worth the risks.
Working with them you become designer, manufacturer and test jumper for hardware, which if the design/construction is faulty or maybe has a 1:100 type failure mode, you and your friends could be put into a life threatening situation, with precious little time to resolve it.
Maybe a foolproof design could be done, and you could perfect a reliable routine with adequate safety procedures. But, to do this properly and truly cover all your bases would be a significant effort in research, design, construction, and testing.
Ask yourself first; are you qualified to pursue a design, manufacturing and testing program for a lifesaving device? If your not sure how to begin answering that question, then your most likely aren't qualified. If you don't think that this question is relevant, then you definitely aren't qualified.
If you're serious about it, run your resume by someone like Bill Booth or Ted Strong and ask them if they'd hire you to be lead designer, manufacturing engineer and test jumper.
Next, write up your design and test program, and run that by them, for comments.
Failing this level of commitment, I think most people are kidding themselves when they throw together some hardware, try it out a couple of times on the ground, and pretend they covered all their bases. In reality they're just playing Russian roulette. Only question is how many bullets and how many empty chambers. Most of us, if we are honest, would have to admit that we have no idea what the various failure modes/rates are in these kinds of setups.
Here is a fun link to a carefully thought out, well rehersed strap dive, by three very experience crwdogs.
I've been in a couple of DPs where at break off we were locked in. We had to reach back with our hands and take the tension off it to release. Wow. Never had that happen to me, or heard of it happening to anyone. There is a lot of force pulling the canopies away from each other in a downplane, and it takes a lot of effort to keep the parabatics grip together in the first place. Either jumper relaxing the legs even a bit is enough for it to get ripped apart.
How exactly did you have your legs locked when you had trouble releasing the grip?
In reply to:
Here was our recipe for a solid tri by side.
Here's how I am used to doing it: - start with a biplane - #3 docks but doesn't plane - #1 and #2 transition to a biplane, #2 still has his feet in #3's lines. #1 just has his legs around #2's waist - #2 grabs #3's canopy with his right hand (bottom skin at the left center A attachment point) and kicks his feet out - #1 and #2 take up a parabatics grip - #1 and #2 go hand-over-hand down #3's lines - #3 takes hand grips on #1 and #2 leg straps (we had loops sewn on the harnesses but can be done without) - #1 and #2 fan their canopies outwards, #3's canopy pops into the middle
To downplane, #1 and #2 (the outside canopies) simply turn away from #3, just like a normal 2-way downplane. #3 hangs on for dear life. I found it would help to bend my legs forward at the waist and nestle the parabtics grip in the angle so formed - it added a little friction and helped me hang on, especially during the transition. As it eventually got stretched out anyway, I would dig in hard with my toes. After the first few times, I could hang on as long as I wanted.
On break-off, you can all break at once, or #3 can let go first while #1 and #2 keep the parabatics grip and continue in a normal 2-way downplane.
Sounds pretty good. My first tri x sides in the mid 80's were very similar because we all used 220 7 cells.
The technique I described above was around '98 where we used two Fury 220s and a Sabre 170 loaded at about 1:1 for the center. It might actually an instance where a semi-noncompatible canopy has an advantage. The ZP Sabre had no trouble docking on 2 Furies in a side x side as long as he started above us. Your description of the walking down the lines was what we also did but with the lightly loaded Sabre, it was more of just letting the lines slide through your hands on the way down. We were too cheap to sew loops on the leg straps.
As long as it works and it's under control, there's more than one way to skin a cat! Maybe the only thing that doesn't change is that the center guy is usually the strongest!
I've been in a couple of DPs where at break off we were locked in. We had to reach back with our hands and take the tension off it to release.---------------------------------------------------------- Wow. Never had that happen to me, or heard of it happening to anyone. ----------------------------------------------------------
Look around DZ.com in history & trivia for the Chris Bickerdike thread. He became the first we know of to land a DP and became DP#1. In July 1986, he and Todd Cudnowsky, DP#2 (sp?), rode a downplane in at Raeford with 'death grips.' Todd was only knocked out but Chris was screwed up pretty good.
I wonder if it's the same as the parabatic grip. You had to get in really close when setting it and long legs were a plus. 8~9 out of 10 times you wound up with a very strained normal grip that you worked hard on keeping. When it worked tight, it was a dream to fly in a DP. You just had to do a constant 'wiggle' check to make sure you could break it you were smokin it low.
Look around DZ.com in history & trivia for the Chris Bickerdike thread.
I did. Some very interesting reading. Thanks!
In reply to:
Todd was only knocked out but Chris was screwed up pretty good.
I find it amazing that they survived!
In reply to:
I wonder if it's the same as the parabatic grip. You had to get in really close when setting it and long legs were a plus. 8~9 out of 10 times you wound up with a very strained normal grip that you worked hard on keeping. When it worked tight, it was a dream to fly in a DP.
That does sound like a parabatic grip. I don't think there would be too many different ways of doing that - it's probably the same thing. Do you know exactly how they did it? I can describe a parabatics grip, and maybe find some decent photos.
Ok, I want to hear more about the parabatic grip, something others are wondering about too.
So here is what I remember as a CRW newbie who once took a camp with a couple former Plaid Jackets guys.
If you don't like my description or photo, let's have some better ones!
Jumper #1 has his legs with knees apart, but crossed at the ankles. Jumper #2 has his legs up through the gap between the first person's legs, from the bottom, and then clamps his feet inwards against the first person, against #1's hips.
Grips are therefore kept low, allowing for the rolling of both jumpers, and avoiding feet up at chest mounted handles.
How you best achieve all that while setting up for a side by side I don't quite know. I think the order in which the leg locks are created likely begins with the 'inner' set of legs being presented by #2, which are then clamped by #1's.
A not-that-great clipping from a photo, attached, shows the grip. (From Craig O'Brien's 2007 ParaGear cover photo of the Skyhawks quadraplane downplane.)
Yes, the grip begins with the "inner" legs. Here's how you do it:
First, get into a side-by-side, then face off with the other jumper (so you are both facing 90 degrees from direction of flight). Taking grips on each other's wrists or forearms works well. Put your knees together and stick your toes in the small of the other person's back, toes turned inward. Then grab the other person's legs with your hands and cross them over your chest (forward foot first helps it stay together better, otherwise the forward foot wants to slide off). That's it! Now rotate your torsos toward the direction of flight and grab your toggles. Very important to keep your knees together and your toes in the small of his back the whole time. It's a good workout for your abs. It helps if you think of doing a situp the entire time. It also helps to be tall and skinny. When done well, it is a very solid grip. When not done well, it can start falling apart, especially when you try maneuvers that put stress on the grip (downplanes, butterflies, barrol rolls, pinwheels, etc).
You can practice this on the ground - just sit facing each other on the floor, the first person sitting between the other's spread legs.
Thank you for the parabatic grip details Brian. While practicing on the ground with another guy is of course useful, one gets a lot of snickers from other jumpers while doing so...
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I found it would help to bend my legs forward at the waist and nestle the parabtics grip in the angle so formed - it added a little friction and helped me hang on, especially during the transition. As it eventually got stretched out anyway, I would dig in hard with my toes. After the first few times, I could hang on as long as I wanted. 
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