~This is a quick snippet of something we filmed when we first opened up RLA’s studio lab ~
Two Rope Twin Tension Mini Offset… Backcountry Meets Fire Service
So backcountry meets fire service… sounds like a battle of some sort. So while this “match up” is really neither epic nor epoch, this contest does have some interludes that hasn’t always faired well for either side.
A while back, some well needed direction was given to the fire service in the form of recommendations while in the midst of rope rescue training and while as important as this was at the time, the direction as modification has been slowly creeping along to the point where those who looked to NFPA as their guiding force are now finding themselves in a bind. Smaller gear, techniques, and a tug-of-war between what is and what shouldn’t be considered proper or true safety factor are, has been pushing some interesting buttons on both sides… and for good reasons!
So in celebration of ,what will be a victory for both sides, I thought I’d mix things up a bit and create an hyperbole system. And while yes, “hyperbole” is not meant to be taken seriously… I am highly suggesting we are eventually going to be needing to adjust our paradigms and frame of reference. Standards will not work across the board, but guiding principles will.
So we have here what I have called for this purpose a “mini two rope offset” and is meant… as most of what I normally set up, a proof of concept. Meaning the goal for me is to see if something works within the relative constraints of load, vector forces, gear and human resources in a given scenario.
Not everything works all the time for me. Minimal human intervention is always my purview and mechanical advantage systems could be either over or under leveraged, as small teams require different “torque to horsepower” than larger teams. Resets are always interesting as starting with a simple mechanical advantage may quickly be increased via a complex system, but this can lead to a huge challenge… as many of you can attest to such as going from simple, to compound then complex… which is the way many teach the progression process, isn’t really all that valuable unless you’re in a vacuum.
OK… so the scenario I set up is a pretty basic, but somewhat sizable challenge. My goal was to build a two rope twin tension system that honored smaller gear, smaller teams, but matched what fire guys might be willing to do vs highly trained SAR or backcountry team. It isn’t an juxtaposed in thought. Bear in mind my original opening thought. If generally trained SAR team, which include high angle rescue in their “technique cache”, they are likely using NFPA (1670 and 1006) as their SOP, never really looking at what MRA teams are doing (the reasons generally run around the thought… climbers don’t make great high angle SAR members).
On the Near stage:
- We have a twin (mirrored) tensioned system using a pair of CMC MPDs as the base structure. These pieces allow a very efficient system to be deployed. The mechanical advantage is a 2 x 3:1 giving a theoretical value of a 6:1. No change overs are needed for lowering… simply adjust the ratchets (Sterling aramid 6.8mm Hollowblock prusiks) as needed (remembering that a two rope offset requires both sides of the system to be ready for raise and or lower).
- We also have a gin pole artificial high directional (AHD) being represented via the SMC Vector. It doesn’t take long to see the benefits of this gem. True, there isn’t much room to work under the head of the Vector, but this belies the purpose of the tool. Small and compact means… small and compact, so if rigging necessitates a large aperture for bringing a patient up and over the edge… it is not the fault of the tool. Design follows function. The guying system is a “delta guy”… 3 legs.
On the Far stage:
- We have an Arizona Vortex set in an SA Frame configuration where the two rope system splits the legs. Incredibly stable and versatile.
- The guying legs are set via a Petzl Jag System (huge throw) pulling in compression against the other guying leg via Sterling 5.9mm Powercord… set in tension.
- We mixed the increments here again… a lightweight twin 2 x 3:1 mechanical advantage haul to lower system via two Petzl GriGri devices.
- Cascade Rescue Litter with interlocking long tail bowlines and fully adjustable head and foot setups
So in winding this down, my purpose was to mix the setups. Neither side is what I might suggest for either backcountry or fire service work. Backcountry wouldn’t always be served well if they only used MPDs nor would the fire service typically run a two rope tension system with Petzl GriGri devices. Mixing this up shows a concept that did work with a single person load and a small team.
Peace on your days..