Wednesday 7 December 2011

Friday 10 June 2011

Read below for issue with Petzl Gr Gri 2.


Detected dangerous failure in 2 of PETZL Grigri

Vista de una cuerda de 10,2 mm. salida de la guía y pellizcada.
Con la cuerda en ésta posición, el Grigri 2 deja de bloquear la cuerda, que resbala.
Vista lateral de la cuerda fuera de su recorrido de seguridad.
Hueco por el que se escurre la cuerda fuera de su guía y queda pellizcada.
The Grigri 2 of Petzl, which replaces the popular and long-lived Grigri in the same house, a fault in its design that makes it potentially dangerous. CampoBase received Grigri 2 provider of the company in Spain (Vertical SL) just three months, in order to test it, analyze it and conduct a review in the pages of our magazine (see next month's issue of July).
After securing the climber both first and second climbers and point out its strengths and failures, surprise jumped a few days ago when, after arresting a fall, the insurer (our tester) was unable to immediately rope climber, who wanted to repeat the step. We used a string of 10, 2 mm (the device supports ropes from 8.9 mm to 11 mm, with a diameter optimal use from 9, 4 and 10 mm, 3 mm). Our astonishment and surprise was enormous: the line had moved from his guide and was stuck under the bottom of the lever, dangerously pinched. A strong pull of the hand, still holding the rope inert, was used to unclog the line and allow the progression of the climber. But the shock had been tremendous. The rope has not lost his place to stop the fall, but did so when the climber grabbed onto it to go up, leading to the imbalance of the insurer, who grabbed the rope force and provided with that gesture to kick the rope guide the product (see photos 1 to 5). A gesture repeated a thousand times with the first version of Grigri that, however, never had problems of this type.
At first we blame the incident to an incomprehensible accident, but did not lose sight of the incident. Two days later, there was the same and also by chance, this time during the maneuver of lowering of a climber who had completed his route. With the device locked while the climber dismounted the road, the simple gesture of grasping the tightrope again lead to the same abandon its colase space and the left side of the device. Again the rope pinched dangerously.
This time, I discussed with a group of climbers who were in the same school, and to our surprise, one of them confirmed that he had suffered the same problem. Then asked about other climbers have entrusted us with the same comment on the Grigri 2. In successive days, very easily provoke a dangerous maneuver (with the climber hung almost to ground level), confirming the shortcomings of a device that, today, should lose his place in the market.
The characteristics of the first version of Grigri prevented these blunders: the lever was oversized and was close to the hook further back on the rotation axis thereof. Moreover, and above all, the tab is behind the string out of the force is significantly larger in Grigri, that the Grigri 2, and less vertical position, creating a 'dyke' by which rope does not leak to the left, which does not achieve the new version of the device.
The failure Grigri 2 is the more important if one considers that many climbers use nine-millimeter rope with which it even easier to escape the rope is pinched and dangerously. In addition, once tweaked, the device stops to block the rope, which slides down the device!
We checking with a string of 9, 2 mm and the result was negative eloquent.
Text and photos have been already forwarded to the Petzl distributor in Spain and hope that motivates a thorough investigation of Grigri 2 by the French manufacturer. Certainly not recommend using this device.

What we've been up to

The inevitability for being busy is I've been a bit slack keeping the blog up to date. Since the last posting we've had about four school bookings, an ML assessment and ML training course, an SPA refresher and I've squeezed in a family holiday.
As Chair of AMI I've had a visit to Ireland for the MLTUK board meeting and had a few days climbing afterwards.
So overall a busy time and lots on in the coming weeks. There are a couple of places available on the ML courses in June.

Saturday 23 April 2011

Film support work for BBC The One Show

In March Paul supported The One Show's (BBC) nature expert Mike Dilger in a quest to find hibernating bats in Ease Gill cave. With the expert help from Professor John Altringham we descended Link Pot and had an extremely successful day.
The show was screened on Thursday 21st April and can be seen here
http://www.bbc.co.uk/iplayer/episode/b010jrqr/The_One_Show_21_04_2011/

Friday 22 April 2011

April ML courses

A fantastic week of weather in the Lakes and 20 people on ML courses. 12 very happy people on training and 8 on assessment with 7 passing and the 8th just a night nav re-assessment to undertake. So congratulations to all. May MLA is full but places on the training. Other courses still have places available.

Friday 1 April 2011

Caving work in the Dales

Just completed an excellent week of caving work with IM Marsh students on a course organised by Duncan Morrison. Duncan delivers the LCMLA caving courses for Apex Training. We had an intro caving trip into Longchurn on day one and then a teaching SRT day followed by a short vertical cave and then a longer SRT trip on the second day. These two days were then repeated for the next group. Motivated, able students' made it a very enjoyable week.

Friday 25 March 2011

Safety alert on abseiling with prussik on leg loops

Safety alert on abseiling with prussik back up on leg loops
This came to me from Pat Littlejohn in the British Mountain Guides newsletter and makes interesting reading:
Summary - Using a prussik loop back up on your leg loop can open the buckles which are 'cinched' tight (by pulling), now increasingly found on modern harnesses, with dangerous results.
" Last summer on a Technical Alpinism course I taught clients how to protect an abseil with a French prusik clipped into the harness leg loop, a standard technique used almost universally. While using this later abseiling from a gendarme, one client allowed the prussik to bite whereupon the harness leg loop opened and he was left dangling from his waist belt with the prussik jammed against his belay plate. Luckily he was nearly at the end of the abseil and other clients helped him to unweight and free himself.
Wanting to see how this had happened I tried it using his harness and the leg loop undid every time. We then tried other harnesses in the team (which were not identical but similar construction) and again this happened.
All were new harnesses which had leg loops with buckles which 'cinched' tight (by pulling) rather than being back-threaded in the old style (as the leg loop buckles on the harness I was wearing). What happens is that the karabiner of the prussik lodges at the buckle, which then opens because it is being pulled at an angle which 'cinching' buckles won't take, i.e. a force from behind the buckle. This is much easier to demonstrate than to explain!
So many modern harnesses now use 'cinching' buckles on the leg loops, or are in the “Bod” style, that we may have to revert to the method of protecting an abseil with a prussik by clipping the prussik into the belay loop of the harness (usually with a quickdraw or cow’s tail to extend either the prussik or the belay plate), I have always thought this was a safer method anyway, but a bit less convenient and involving more gear.
What worries me is the number of people out there who have been taught to abseil with a French prussik clipped into leg loops with 'cinching' buckles - a lot of people I suspect. "
I've tried to get this to happen on a new Wild Country harness without success - see pictures below. Climbers and instructors should, however, be aware of this possibility.