Lesson Learned

[Calvin19 0]

what design did you use? 3 or 4? did you do it with nate? they were doing it today as well. the sketchballs.

[Tornolf 0]

4. I was putting together most of the mechanical parts of the system we were going to use. Actually it was what I was going to use, since somehow I became the test jumper...

With 4 there's almost no force on your mouth at all. I was using some really old suspension cord and I'm thinking it would be better to use something like dacron, then fingertrap a 6" piece over the loop that goes in your mouth. So you'd basically pull the loop through the 6" piece so the 6" piece can be a protective sheath. It seems like using a rubber tube or tape to protect the line from your teeth causes major hangups when you release. Then again, since the force is so low on the last line (approx 1/16 the total force), you should be able to tell when the line needs to be replaced long before it fails.

Other than that it seems like the safest system you can tow with. With an active and passive cutaway system, it's really easy to bail if shit goes wrong. We ended up planning to use a grigri to pay out line, which was attached to a riser, which was attached to a biner attached to a rope spanning the back of a truck. If you have a cutaway handle with 2 ends (looks like a Y) then either the person on the grigri or a person beside them, designated to cutaway if shit goes down, can chop the rope. Basically you end up with 3 people (jumper, grigri payout, cutaway person next to grigri) that can chop at any time, completely bailing from the tow.

I give myself like a 75% chance of not dying.

A waddling elephant seal is the cutest thing in the entire world.
-TJ

[Calvin19 0]

beware!

also, if you are in what is called a 'lockout' (some fucking brilliant BASE jumper in a PM compared a lockout to a 'downplane with a truck', and he was totaly correct, I like his thinking.)

A lockout can happen at pretty much any angle, but usualy not faceing away from the tow truck with a BASE canopy, if you are towing to fast, it will happen in line of tow, then its no big deal, but with a payout setup, relly beware, this 'lockout' can happen really close to the ground. and IF you chop the tow line or get chopped, your horiziontal velocity will stop pretty quick, and you will surge, A LOT, into the ground. and break your tibia/fibia. and that sucks.

also, For payout, starting from the tow vehicle is best, OR, the top of something close behind it like a flatbed trailer OR, as we did it, running about 20' behind the car. get the wing flying, and SLOWLY increase speed. get to the point where you are just barely flying, then add about 5mph. there you can let off the brakes (rear risers work better, but dont do that near ground, to slow reactin, then massive movement) and climb, keep the tension of tow line the same for the whole tow.

and man, really, really buy something besides dynamic climbing rope. not only will the rope be destroyed if your towing on anything but grass, but 60meters is not enough. high point of 60 meter climbing rope is about 30 meters. maybe a little more, and even the surge from release then is intense.

lookout kids. i have said before, this is the sketchiest thing i have ever gotten good at.

do it on water of you can. there its pretty comparitively safe.

of course, this coming from me means nothing. but anything i say is sketchy. if you want to be safe, go do PCAs with no PC.

[tfelber 0]

I've spoken with you a little about this in PM's but this info brings up a few issues regarding my situation.

I'm planning on pulling with a boat with me starting on the shore near water with a slight headwind to get the canopy inflated and flying. I've been practicing kiting so I'll have a better feel for when it's time to hit it.

I intend to have 300' of line with multiple wraps around a pulley so more rope can be fed out or released completely, sort of like a windlass.

My intention is to have a pilot cutaway as you've mentioned. The observer on the boat could release the line or cut the line with a hook knife in the event of a hangup.

The canopy is actually a 9-cell paraglider and I intend to release my cutaway once at altitude. Once I get it flying and figure out all the nuances, I've thought about building a cutaway for the canopy, and wearing my BASE gear over the harness. Cutaway, go into freefall, throw my PC, and land on the beach.

Soooo, do I sound like a lunatic about to hurt myself and others or does it sound plausible???

[Calvin19 0]

sounds familiar!

connect the '3loop' release to the risers of the paraglider you are cutting away. then, as you gain altitude, switch the loop from your mouth to your hand, other wise you could be missing a few molars after release.

remember that your not as high as you think you are. 300' of line usualy means 150' or less.

[GreenMachine 0]

Hey Calvin,

Thanks for the photo, a master rigger is loaning me a
sewing machine so I can practice sewing patches for
my rigger's test so maybe I will try to make one.

Sorry for the late reply, but the wife and I were on an
Alaskan cruise. Nope, not the one that ran aground
The fjords up there are beautiful, some are quite tall
but it looked like almost nowhere to land except the
drink, which is damn cold.

Rigger, Skydiver, BASE Jumper, Retired TM

[Calvin19 0]

i was up there scouting some Es near that one huge mountain, and i also looked at some Ice jumps, obviosly land in the drink. the salty drink.

nothing really big enough, it is over water, but there were icechunks/burgs directly below the exits.

[tfelber 0]

So I rigged up one of the cutaways you mentioned and it works quite well. With my full weight hanging on it the pressure needed to hold the last loop is minimal, it can easily be held with two fingers or your teeth without slippage or risk of injury. And when you release it the system cuts away instantaneously. Thanks for the idea.

I'm going to use a double wrap of break cord for an emergency break away to deal with excessive loading so I don't damage the boat or the canopy. I'm also going to use two observers in the boat; one holding the loose end of the rope wrapped around a horizontal barrel and one with a hook knife in the event of a hangup.

I'll let you know how it goes.

[Calvin19 0]

if you do have a weak link on the jumper, be sure it is on both ends of the cutaway rig, i fnot, it wont release.

its obvious, but just making sure.

[tfelber 0]

I was actually thinking of doing it between the tow rope and the cutaway. Do you know the effects of water on break cord?

[Calvin19 0]

I do not. have not tested that at all.

[dploi 0]

Quote

As mentioned many times before, this type of towing is a BAD idea even with a cutaway system!

Second that. Towing is unnecessarily dangerous, through and through. There are ways to pull off towing, but a BASE canopy and a rope are a really bad start.