No25. Ghost Technique (D-SRT)
Acronym’s are confusing, perhaps it is best to clear the subject up before further rope systems are created.
DdRT= Doubled Rope Technique
What is seen, as of december 2015, as the most common arborist rope system. Simple and elegant but with profound flaws that make it troublesome for more than the most simple tasks. The rigging is doubled over a branch, ring or pulley, thus the name….Doubled Rope Technique.
DRT= Double Rope Technique
Commonly and mistakenly the name given to DdRT. Double means 2.
SRT＝ Single Rope Technique
A single leg (rope) system that stems from caving. The anchor is tied and the climber moves away from it.
SRT= Stationary Rope Technique
Stationary is the updated term that arborists use for single leg systems because it defines it against DdRT, a system that also only uses a single rope. Stationary Rope Technique opens new possibilities for simple and refined Access and Work Positioning.
S-DdRT= Stationary Doubled Rope Technique
A system that connects 2 small diameter ropes together that run through 1 belay device.
A system that connects 2 ordinary diameter ropes together. Each leg runs through a separate belay device.
D…?= D stands for Dual.
Climbing on 2 distinct ropes and belay devices.
D-SRT= Dual Stationary Rope Technique
D-DdRT= Dual Doubled Rope Technique
D-SRT
In November 2015, Eric Whipple came across from the east coast of America to teach about D-SRT (dual stationary rope technique) at The Wooden Hand Tokushubasai Technical Workshop. Eric is a leading light on all ideas SRT. He has refined a system that he calls The Ghost Technique as it allows him to almost literally pass through branches. What I mean by this is that he can be in a position, toward the bench end, that gives no support for his weight, and is able to create new anchors and re-directs by alternating weight into 1 or the other system. There is always a completely safe anchor to climb on while the second line is thrown to a new anchor. The 2 ropes may be kept parallel (symmetrical) or diverge between different anchor points (un-symmetrical). All this complex re-routing of ropes is kept in check by his clever belay set-up. Eric uses 2 Compact Bulldog Bones that he has modified with a Rock Exotica Nano Swivel into the karabiner attachment point and he connects both Bones, via triangular maillon into the Rock Exotica Large Round Rotator Swivel. This set-up allows each bone to modulate left and right via the Nano swivel and also allows Eric to reorient himself underneath the 2 Bones with no twisting at the belay point.
1 - Gordon Svedberg Compact Bulldog Bone://
2 - Rock Exotica Nano Swivel
3 - Triangle Maillon
4 - Rock Exotica Large Round Rotator
Eric demonstrated this technique through the crown of a huge Quercus gilva (Shi-noki) into an Ash and finally descended down a Hinoki cypress. He travelled approximately 30M laterally at about 25M height with control and safe climbing at all times. One aspect of the D-SRT technique is that it frees the climber up from having to use a lanyard. This means that in the event of an aerial accident Eric’s ground worker can, more likely than not, rescue him via a trunk belay system. As my work is 100% removal working from a trunk anchor poses many risks so I would like to write this article about designing a D-SRT crown anchor system. Simple enough but how can we utilise this idea in combination with Eric’s Ghost technique? I think a clue lies within several systems. If we combine ideas from both sides of S-DdRT with a knot blocking crown anchor we may just get close to the efficiency of Eric’s.
SYSTEM
SYSTEM１
A system that connects 2 small diameter ropes together. Both legs run through 1 belay device.
SYSTEM２
A system that connects 2 ordinary diameter ropes together. Each leg runs through a separate belay device.
System 1 has many benefits and a few pitfalls. It is a stationary system but one that retains at all times the ability to anchor retrieve. The smaller diameter rope 8-8.7mm rope has borderline static strength at the apex point of the system and has questionable wear and tear capabilities through rubbing and scuffing. More importantly and dangerously there is a possibility of one side of the system opening which would send an unaware climber into free fall. It is a raw idea that needs refinement through equipment development. A belay device large enough to accept 10mm rope and with 2 independently functioning cams to stop inadvertent dropping could mean an interesting and relevant system.
The 2nd system has a very different technical nuance. Firstly we switch to standard diameter rope so what we lose in functionality with 1 belay we gain in flexibility through the option of splitting the system in two. This means that with a little bit of rigging at the anchor we can go instantly from a S-DdRT system into a D-SRT one, retaining options for remote anchor retrieve with the former and access to Eric’s Ghost Technique, when it is needed, with the latter.
Anchor
The left hand shows an SRT rope that has been knot-blocked with an alpine butterfly and Sinnet chain. The ring is a 28mm DMM anchor ring, the small size allows safe knot-blocking and as the working end is in front of the belay the anchor is quickly and easily retrieved.
The right hand shows a Stationary DdRT system that runs through an anchor ring.
A simple technique is to cut a DdRT rope in half, using 1 section for a climb line and the other for additional duties which include but are not limited to:
Anchor leg for non-isolated access
ⅱ） Rescue line
ⅲ） Traverse line
ⅳ） D-SRT
The idea is to have a disconnecting element between 2 sections of rope that allows the climber to get the most out of rope within the system by narrowing redundant rope length down. The rope may be joined with a hard connection (karabiner/maillon), soft connection (knot) or a combination (anchor ring and knot block). Of course the second length of rope may run independently from opposing anchors or be rigged into the Onigiri anchors two rings.
Compact Bulldog Bone
A - Top Arm, B - Bottom Arm, C - Chest Harness Attachment Hole, D - Chest Harness Attachment D-Ring, E - Original Karabiner Attachment, F - Rock Exotica Nano Swivel Modification, G1 - Top Gate (bollard sits between G1 links), G2 - Bottom Gate.
The Bone comes with 3 bollards, Small, Medium (factory installed) and Large. There are additional cotter pins for reattaching the side links. The bollards can be exchanged to tune the grip and release on the top friction arm (G1), this accommodates different rope diameter and construction, climbers weight and preferred climbing style. The rubber at the ends of the top friction arm are designed for comfort but also keep the arms from cross-loading with the bottom arms. Never remove them and return the product to the supplier if they are missing. When the rope is installed and the Bone is weighted, slowly pull the top arm (G1) downwards to initiate release, let go to stop. If it is slipping, exchange bollards (H) for the next size larger, alternatively if it is difficult to release go to 1 size smaller. The hole (C) at mid spine and D-ring (D) is intended to advance the Bone via chest harness when climbing SRT and should never be used as a working-end attachment for DdRT.
Onigiri Anchor
Knot Blocking is an important technique for SRT crown anchoring and rigging the 28mm anchor rings into Teufelbergers Pulley Saver lends itself a huge amount of technical flexibility. By the way, Onigiri is a rice ball, the triangle on the Pulley saver kinda looks like one.
While we are talking about food, I stumbled across the Pulley Saver factory in Matsumoto, strange, I thought Teufelberger were based in Austria !!
