On 2003-01-22 20:50, RickI wrote:
Murdoc,
You raise a good point. The Wichard and Tylaska or "tip release" snap shackles tend to open more readily. There is some evidence to suggest that "side release" snap shackles such as the one shown below may not release if heavily loaded, are rigged upside down, are jammed with sand, etc. The "side release" shackles do cost less, about half that price of the Wichards and Tylaskas but what good does the savings do if they contribute to an accident.
Exact, Rick, this kind of snap shackle has the problem, not the Wichard.
I tested this snap shackle myself last year in a SELF TEST, it's easy: fix a rope somewhere, hook in, have some 20 cm to the ground and something soft there, then relaese with your full body weight pulling, later take additional weight. Try it also without looking at the QR, and also with your "weak" arm. I did it up to 105 kg.
In a first round of testing I noticed that the QR didn't work with the chicken loop.
In a second round I tired it with a ring. While testing, I had the feeling that I was not sure if I could mobilize the necessary power to release in an emergency situation. After 4 tries the snap shackle was unable to close, bend, unusable!
I tried the Wichard next just with the chicken loop and immediately felt that it was so much easier to release. Since then Wichard is a very good friend of mine...
Tests conducted by several magazines have shown that the Wichard is clearly superior to the new systems of Naish, Gaastra, Wipika, Takoon etc. The main difference in the tests was the power necessary to release the QR under pulling power of 100 or 200 kg as published by the German kite magazine.
Here are some data for a pulling power of 200 kg which show what kind of power you need to release the QR in such a situation:
Wichard 5 kg
Flysurfer 13 kg
Naish 15 kg (please note that you need to push the 15 kg away from you according to the system which is much more difficult than to pull)
Wipika 51 kg
Gaastra 73 kg
Here the data for a pulling power of 100 kg:
Wichard 3 kg
Flysurfer 5 kg
Naish 11 kg (please note that you need to push the 11kg away from you according to the system which is much more difficult than to pull)
Wipika 40 kg
Gaastra 40 kg
In a situation when your safety depends on being able to release the QR within a fraction of a second, you should not need more power than 5 kg to release the QR, I would say...
The test data confirm some of my own impressions and testing. And why should I compromise regarding safety systems or why should I guinee pig for the industry? That's why I feel better using Wichard...
<font size=-1>[ This Message was edited by: Wolfgang on 2003-01-22 21:44 ]</font>