rigging problem

[chh]

So since it's been pretty quiet in here lately I thought I'd throw this work related rigging problem at you guys to see if you can help me. Maybe someone will see something I'm not seeing.
Here's the problem. We have to remove some small trees and brush from behind a house. The problem is that the slope is VERY steep and there is a rhodo thicket and other lower vegetation we are not going to disturb in the process of getting the debris out. There are a number of larger trees, however, to set up highlines. Basically, individually bundled piles of brush and/or logs need to be lifted off the ground to around 20 or 30 feet and then travel along a highline/tyrolean up to the chipper and truck.
Now, this is a very simple problem (one we've tackled many times) if it happens to be in a straight line. But here we have to make a turn around the house, i.e. NOT a straight line.
Maybe, for you rescue folks, you might think about it like moving a litter along a tyrolean - except you have to make a turn.
Now the obvious thing to do is to haul in stages. Haul up to one highline, haul along the highline and lower on the other side. Reset the highline and do it again. This reset would happen at the bend so to speak. This is, however, very time consuming. I would like to be able to climb and do all the rigging, and then do the rest of the work from the ground until it's time to take the rigging down.
Our materials: One winch (your haul team), a host of burly ropes and pulleys etc. At the moment let's assume you want for nothing.

My main problem is this. I've figured out a way to do this ONCE. After that I have to climb up and reset the winch line through a pulley at the bend. I don't want to do this. We are a three man crew and I don't want to stage someone in a tree for the day just to put a line through a pulley.
Thoughts? Maybe some of you who have participated in pit and/or steep hillside cleanups might have some insight as well?

If this is to vague or whatever I might take the time to scribble up some diagrams or something, I just thought someone might have an approach I hadn't considered. Or like, "hey dummy, THIS is how you make the litter do a turn on the tyro.....DUH!" Oh, and it doesn't have to be to rescue standards, it just need to not break.

Also, I don't know how much time I have to figure this out. If we end up there before I hear back from you guys, I'll let you know how we did it.

-c

[cavedoc]

Well one answer would be to have two jiggers (4:1 pulley on each side) with pulleys on your mainline at the bend. Jigger #1 is in place to start. As the load approaches and goes by, attach jigger #2 above the traveling load, tighten it, then loosen jigger #1 and release it. Reverse process going back up if needed. But this would require someone to man it each time the load goes by which I'm not sure meets your original parameters.

[Stridergdm]

There's a saying about great minds thinking alike, but in cavedoc's and my case, I'll chalk it up to good teaching since I was about to suggest exactly what he mentioned. So that's two votes for that method.

[Scott McCrea]

I'm thinking ski lift sort of set up. Or donkeys.

[shibumi]

Relatively simple answer is to make the redirect part of the trackline system. This may be hard to visualize without diagrams...

Once the load hits the redirect, then it gets locked into the redirect simply by running into the pulley (since this is not a life-safety load I am going to ignore possible improper loading of the pulleys involved since solving those problems would require a lot more writing), release the dumb end of the trackline at the house and the redirect line
now becomes the other end of the trackline. Have the redirect rigged so you can let it out in a controlled fashion such as in a twin tension traverse. Basically you are creating a twin tension traverse with three points instead of two.

[snoboy]

Some sort of ski lift type hanger/sheave system would be the slickest, but I doubt you want to make up something like that for a one time job. Of course if you anticipate doing this elsewhere inthe future, it could perhaps be a useful tool and give your crew an edge... Hmmm, do I sense a product marketing opportunity?

I envision a large diameter sheave, with two guide sheaves, and some sort of rope clamp like a chairlift grip. Your guide sheave postition would have to be adjustable to account for different angles.

I've been tring to think of how to do it with standard gear, and so far I can't get it without someone up the tree at the redirect.

[Cavernuke]

I'm responding to your question about removing material from a worksite. I wouldn't recommend this for Rescue use.

Back in the day before shipboard cranes, general cargo ships were unloaded using a technique called "Burtoning". If you look at pictures of old steam freighters, you will see a forest of masts and booms. There were 2 booms for each hatch; the head of one boom would be rigged directly over the hatch; the other would be positioned over the dock. Unloading the hold, the cargo would be winched up using the "hatch" boom until it was clear of the hatch. Then the "dock" boom would take up the load as the cable for the "hatch" boom was eased, swinging it over the dock. The load would then be lowered, and the process repeated for the next load.

Seeing as you have plenty of trees at the entrance, these can serve as your "booms". The 90 degree turn can be accomplished with a third tree. If you already have the gear, all you need to do is recruit your "pullers" for use as human winches. Beer and pizza should suffice.

Nuke

[cavedoc]

Or donkeys.

Or goats! Leave 'em there for a month then come back and get them. Presto! No brush. And the ground would be nicely fertilized.

[chh]

Ok, so in summary so far we have what sounds like two options. One involves a fixed redirect and somehow jockeying the load around at the fixed redirect. The other, if I'm understanding you shibumi, is to make the redirect releasable so that once the load hits it and everything on the "first" part of the haul is set loose, the redirect pulley travels with the load to the truck/winch.
So far, I like shibumi's suggestion, but will all that stuff return to the original position once the load reaches the destination? This is really the crux of the issue. Getting the system to reset after the first trip is made without me having to leave the ground. Also, I'm not worried about improper loading of the pulleys really because we aren't dealing with lives and most have burly steel sheaves anyway. I feel certain that with shibumi's method we could return the winch line past the recirect, but would there be enough weight to get the end of it down to the work area at the bottom of the tree at the bottom of the slope?
I have to make some dinner, I'll be back.

[shibumi]

If you rig the redirect so it is releasable and haulable then yes. That's how a twin tension traverse works. Use a retrieval line to bring the winch line back to the starting point once the redirect line has been reset.

[chh]

Thanks shibumi, I think I've got it figured out. I guess I was hoping to use gravity to get the winch line out of the tree at the bottom of the slope, but only because I didn't want to use a retrieval rope. I'm that lazy.

Just out of curiosity, how would the process at the redirect be different with a litter? Would the redirect pulley be fixed, hence a small lower out of one side of the redirect and on to the other? Dual traveling crane set ups? Or would you still use a releasable redirect in some way?
My rescue rigging colloquialisms are not really up to snuff. I've never had any training in that venue.

[shibumi]

Not really, I'd just make sure that the way the system gets loaded when it is locked doesn't place at the redirect any of the equipment such that the loadings aren't in an axis that compromises their strength, like pulling the end knot of the haul line against the pulley sheaves. Like I said, it's hard to describe with just words without writing an essay :)

[chh]

sorry, I was editing while you were writing. Gotcha.