Oops, didn't realize that the other thread was a First Amendment Free Zone so I'll start one that isn't. And it doesn't appear that this discussion is really pertinent to the initial topic anyway.
Thanks Brian. I experimented, checked my knot book, and googled without success. Then I read your last post and went back to the source thread and noted Post #8. I resumed efforts with my loop of webbing and carabiner. Thanks Steve, it ain't easy but it can be done.
I had previously been on the right track but didn't think things would hold together well enough to screw things up. Here - I believe - is how to screw things up.
For illustrative purposes...
Grab a foot and a half of 3/16 inch line or something in the ballpark and tie the ends to form a (hang) loop.
Hold a carabiner in front of you so's up is up and you're looking at its (pick one) port side.
With the tied ends of your loop up, take the middle/bottom end through the top of the carabiner - near/port to far/starboard.
Take the end through the standing stuff and around again to form a double double wrap.
Maybe this'll help. (I previewed a version of this a minute ago but the damned forum decided that I really didn't intend to have all those spaces in there. If you want to see things more clearly copy and paste into word processing and replace all the periods (monospaced font).)
....|............|
....|............|
....|............|
....|...../\.....|
....|.....\/.....|
....|.|-|.||.|.:.|
.--------------------
/...|.:.|.::.|.:.|...\
....|.:.|.::.|.:.|
.--------------------
/...|-|.|-||-|.|-|...\
If you do this with webbing the wraps will overlap and bind some and the shape of the carabiner will cause the mess to compress longitudinally under load and it's possible for it to hold reasonably well.
To accomplish this in the field you need to first complete a wrap with a - let's say - left hand twist, preferably load it up a little to help it bind, then complete a second wrap with a right hand twist.
I dunno, I've been something of a knot freak since I was about eight years old and it wouldn't occur to me to jump through this many hoops to try to kill myself. This abortion certainly should not be dignified with a term such as "magician's knot". It's not a knot of any kind - just a multiple wrap around a rod that jams a bit every now and then.
Here, again, is a quote from Wills Wing's Technical, Support, Harnesses, Hang Loops guy (addressing the owner of the small version of the glider involved in the recent accident):
"If the main is properly maintained, and periodically replaced, it is never going to fail anyway, so the back up is sort of pointless. Years ago we didn't even put backup hang loops on our gliders, (there's no other component on your glider that is backed up, and there are plenty of other components that are more likely to fail, and where the failure would be just as serious) but for some reason the whole back up hang loop thing is a big psychological need for most pilots."
I'm just not a fan of throwing stuff into the breeze to compensate for shoddy procedures and equipment. If one is not confident in one's ability to apply wraps in a uniform manner, one should keep available in the bag a length of line to ensure connection to the keel.
"magician's knot"
Moderator: CHGPA BOD
Didn't quite follow the whole rope gymnastics, but I got the gist of it. I guess it comes down to what Steve said: if you only hook through one span of strap you're good; two and you're possibly in for it. Unfortunately it's hard to shorten and go through only one loop without tying knots that weaken the strap, hence all the wrappage and multiple loops.
Hence the backup. Plus some of us mere fools have never bothered to replace the primary.
Hence the backup. Plus some of us mere fools have never bothered to replace the primary.
Brian Vant-Hull
-
Tad Eareckson
- Posts: 304
- Joined: Wed Feb 09, 2005 8:50 am
Yeah, it's a lot easier to demonstrate than describe but I was thinking some more about it later Tuesday and came up with a better:
name;
description of its execution; and
prescription for use as a suicide aid.
"Not Knot" works a lot better for me than "magician's knot.
The latter two items work best in combination.
1. Hook into an unfamiliar (new, borrowed, demo, rental) glider normally and do a full hang check. Damn. Too low.
2. Stand up and take a wrap.
3. Go down again, full check. The wrap binds and sets. A bit low still.
4. Stand up. Take another wrap - in the wrong direction - actually an unwrap - but that was a good fifteen seconds ago and you've forgotten.
5. Go down again. Nah, why bother? The last one was almost close enough, this'll be about right, I'm hooked in, I've already done - not one but - TWO full hang checks.
6. Step up on the ramp.
7. Clear!
8. splat
The Perfect Storm
To restate and simplify further...
Wrap, tighten, unwrap. (It is neither necessary nor recommended to step off the ramp to prove the point.)
I hand stitched my own kingpost mounted suspension years ago and have no intention of ever replacing it. Only one run of webbing is routed below the sail and through the carabiner but there is a strap joining the sides above the keel in case my stitching or the quarter inch bolt are ever found wanting.
The only direct sunlight it feels is whatever makes it below my sail in flight. The upper area is always protected and when parked the lower run is tucked between the sail surfaces.
Yeah, knotting isn't gonna increase the strength of the system any but the difference will be something analogous to using a four rather than eight pound sledgehammer to kill a mosquito.
One inch Type 18 flat nylon webbing. Six thousand pounds. Three tons. You're hanging from a doubled length. Six tons. For me - 24 Gs. Tie a knot. Be generous and go back down to three tons - 12 Gs. Skydivers are happy with two thirds of that.
How much can your airframe take? How often do we hear about those things folding up in non aerobatic flight?
name;
description of its execution; and
prescription for use as a suicide aid.
"Not Knot" works a lot better for me than "magician's knot.
The latter two items work best in combination.
1. Hook into an unfamiliar (new, borrowed, demo, rental) glider normally and do a full hang check. Damn. Too low.
2. Stand up and take a wrap.
3. Go down again, full check. The wrap binds and sets. A bit low still.
4. Stand up. Take another wrap - in the wrong direction - actually an unwrap - but that was a good fifteen seconds ago and you've forgotten.
5. Go down again. Nah, why bother? The last one was almost close enough, this'll be about right, I'm hooked in, I've already done - not one but - TWO full hang checks.
6. Step up on the ramp.
7. Clear!
8. splat
The Perfect Storm
To restate and simplify further...
Wrap, tighten, unwrap. (It is neither necessary nor recommended to step off the ramp to prove the point.)
I hand stitched my own kingpost mounted suspension years ago and have no intention of ever replacing it. Only one run of webbing is routed below the sail and through the carabiner but there is a strap joining the sides above the keel in case my stitching or the quarter inch bolt are ever found wanting.
The only direct sunlight it feels is whatever makes it below my sail in flight. The upper area is always protected and when parked the lower run is tucked between the sail surfaces.
Yeah, knotting isn't gonna increase the strength of the system any but the difference will be something analogous to using a four rather than eight pound sledgehammer to kill a mosquito.
One inch Type 18 flat nylon webbing. Six thousand pounds. Three tons. You're hanging from a doubled length. Six tons. For me - 24 Gs. Tie a knot. Be generous and go back down to three tons - 12 Gs. Skydivers are happy with two thirds of that.
How much can your airframe take? How often do we hear about those things folding up in non aerobatic flight?