Extraction Technique; Insurance Rope thru Recovery Strap Loop

[WCVanHorne]

So I've done the odd very simple extraction over the years with other people's trucks and/or on the farm. All very light ones; ie. nothing really mired and mostly a little help out of the snowbank. Anyhow now that I'm in the 4runner for almost a year I've done a couple little assists with other people's equipment. Before I get in trouble I was reviewing all the techniques that I haven't really used in a while and getting together my own complete set of straps, clevis, etc. that I trust.

Now the strap breaking doesn't worry me much and a blanket over the top lowers that risk down to maybe some scuffed paint or really minor dent. The main failure mode that keeps me awake a night is the scenario where a tow point, or part of the hardware on either end fails before the strap and the remaining metal attached to the recovery strap (clevis, bits of receiver, etc.) becomes a missile launched by the stored energy in the stretched strap.

After pondering this this evening a technique occurred to me that I don't think I've seen anywhere else yet. Why not take a medium strength rope and loosely tie off the strap loops to another member of their associated vehicle, leaving perhaps 7' of slack. This way if something gave way the bit attached to the strap would be restrained.

Now I fully realize that there are some secondary risks such as too short a rope slack given the recoil of the strap and additional movement of the tow vehicle or setting back of the other vehicle. This could lead to the metal being relaunched if the rope snapped but probably not a severely as it is likely sagging towards the ground and there would be much less re-stretch in the strap since the rope is comparatively weak. Also if you are not careful you could get the slack tangled. Of course a self feeding or light twine release coil would do the trick too. Both of these shortcoming are mitigated by short recovery pulls as well.

Anyhow any thoughts? Overkill? Adding more complexity and risk and not actually mitigating much? Am I crazy and up past my bedtime?

PS. Here is an interesting review booklet I ran across produced by Purdue. Not very concise but some good photos and stories: http://www.ppp.purdue.edu/Pubs/PPP-98.pdf

 

[KidVermicious]

I think it's overkill, and adds complexity to a task that you want to keep as simple as possible. If you don't trust your shackles, get stronger shackles.

 

[Doc2012]

I think you're on to something here.

After seeing what a wire or a rope can do, I'm hesitant to use them, even in the simplest of exctactions.

I know what Big Navy does is use what's called a "Tattletale". Basically, a small, weak section of rope tied to a big rope.

The smaller, weaker rope; a 1-2' piece of 550 cord; is tied to the larger rope, in this case a mooring line, at BOTH ends. The "tattletale" has some slack in it, but not a lot.

When the Morring line is stretched, the "Tattletale" stretches with it. If the "tattletale" snaps, then you've got some problems.

Basically all it's used for is to tell the guys is the mooring line is getting stretched beyond it's limits.

This could be good for something like the straps. But then again, you'd have to be outside the truck to watch them. Not really a good idea there.

I guess what you can do is to get one of those cheapo straps from Wally World, or somewhere like that, and run it through the loop of the strap you're going to be using. Then, take both ends and hook them to somewhere on the frame, leaving enough slack that if something DID go wrong, the other strap would keep it from snaping back at speed.

 

[WCVanHorne]

I think it's overkill, and adds complexity to a task that you want to keep as simple as possible. If you don't trust your shackles, get stronger shackles.

It's really not the shackles primarily as one get those plenty strong. I'm more thinking of the tow point loop or similar failing and then the perfectly intact clevis/shackle comes whipping back or forward.

 

[Intruder]

It's really not the shackles primarily as one get those plenty strong. I'm more thinking of the tow point loop or similar failing and then the perfectly intact clevis/shackle comes whipping back or forward.

If you're buying a proper recovery strap with the correct break strength rating it should break long before your recovery points do. Inspect your recovery points every so often to make sure they look fine and you shouldn't have anything to worry about. If there's a really good stuck and a few good pulls with a strap aren't effective you need to look at alternative techniques - hilift to stack rocks under a tire, winch, winch with pulley to change the angle of recovery, etc. You shouldn't have to pull that hard with a strap if you're using it in the appropriate situations.

 

[Jeremy556]

I think you are thinking too hard. If a tow hook breaks, your line damper should slow down or stop the missile. A tow point breaking isz pretty rare compared with straps or lines breaking, anyway.

As Intruder pointed out, if the snatch strap isn't doing it, you should be looking at alternatives, like digging/lifting the vehicle out and winching.

 

[03_4x4Runner]

If you are relying on the factory tie down straps like on the front of my 4th gen then that is the weak point. It is a shame Toyota does not put good tow hooks on our 4runners from the factory.