reserve soft link assembly method?

[pchapman 262]

I came across reserve soft links that weren't assembled according to the instructions. They were of the 'ring' type, like Aerodyne, Precision, and PdF use. (Not the PD tabbed Slink type.)

The links had the end of the line simply lark's headed around the ring. The line did not first pass through the loop at the other end of the line and then pass over the ring. It looks 'fairly' safe and secure but the load path isn't as the manufacturer intended, and the line larks headed on the smooth ring does not tend to stay cinched as tight as normal.

I just want to double check that there aren't any alternative soft link assembly methods I haven't read about. Sometimes in rigging there are 'accepted' or 'approved' techniques not mentioned in the manual -- but I haven't seen that this is the case here!

I changed the links back to the factory method, and it will be discussed with the rigger, who is experienced and current. Other details will not be divulged.

[fcajump 153]

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I came across reserve soft links that weren't assembled according to the instructions. They were of the 'ring' type, like Aerodyne, Precision, and PdF use. (Not the PD tabbed Slink type.)

The links had the end of the line simply lark's headed around the ring. The line did not first pass through the loop at the other end of the line and then pass over the ring. It looks 'fairly' safe and secure but the load path isn't as the manufacturer intended, and the line larks headed on the smooth ring does not tend to stay cinched as tight as normal.

I just want to double check that there aren't any alternative soft link assembly methods I haven't read about. Sometimes in rigging there are 'accepted' or 'approved' techniques not mentioned in the manual -- but I haven't seen that this is the case here!

I changed the links back to the factory method, and it will be discussed with the rigger, who is experienced and current. Other details will not be divulged.

Would be interested in seeing pics of the links as you found them and as you think they should be... I have only ever used Precision and PD's versions and want to see/hear anything others are seeing with soft links.

Jim

Always remember that some clouds are harder than others...

[pchapman 262]

Attached is a photo of how the link was found, once rotated out of the riser. It's still a bit hard to see what's happening... but of course that's the issue when inspecting.

The other attachment is the drawing from the manual for that Aerodyne soft link design.

[fcajump 153]

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Attached is a photo of how the link was found, once rotated out of the riser. It's still a bit hard to see what's happening... but of course that's the issue when inspecting.

The other attachment is the drawing from the manual for that Aerodyne soft link design.

Certainly that is not as shown in the manual, and I have not seen any manufacturer (or aftermarket discussion) that does it that way. I could however see that as an easy way to mis-interpret the instructions.

As to how structurally sound that would be, I would defer to PD or someone else who might have test experience with them, but it seems like trouble to these amateur eyes...

Let us know what comes of it (though I don't feel the rigger involved need be named either way).

Jim

Always remember that some clouds are harder than others...

[pchapman 262]

I was in contact with the rigger. He said it was the first time he assembled those type links and had a tough time getting clear info on how to do it. Only later did he see a clear picture and by then had forgotten how he'd done it.

Since the Aerodyne manuals have shown a clear drawing for at least the last 2 years, he probably wasn't working off a manual. He may have had vague or misinterpreted verbal instructions.

I seem to recall that Aerodyne ships gear with almost no paperwork, just a CD of manuals. This can make it a little awkward to quickly get gear assembled for someone unfamiliar with it.

The lesson is a simple one about reading the effing manual if one isn't absolutely sure about something potentially critical.

[TimDave 0]

I have some experience testing materials used in parachutes and do know that the strength in different directions is quite different (especially in line/cord). Braided cord (like suspension line) is much stronger in tension (along the axis coinciding with the length). Larks-heading the line on the ring like this creates force that is along the shear direction (perpendicular to it's length). This is an area of concern for structural integrity. It also is easier for the loop to come loose and the link to release than the recommended method. It would have most likely worked fine but this is not something that needs to be found out the hard way. Hope the rigger appreciated you contacting him and helping improve his/her craft.

I have found worse rigging errors than this with soft links also.

[beezyshaw 0]

I designed the ring-type soft link for Precision when I was with that company. One of the objectives in designing the "wrap-it" link was to offer the strongest connector link on the market. One of the ways we achieved that was to make the link longer so that it formed 3 loops instead of the 2 loops of the PD Slink. In testing the link, we certainly realized the potential for someone not running the end through the small loop before putting over the ring to form the locking knot. When we pull tested the link locked incorrectly, their was no real difference in the amount of load it could withstand, but of course the issue with not locking softlinks correctly is that they can come undone easily.

[Gene03 0]

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I was in contact with the rigger. He said it was the first time he assembled those type links and had a tough time getting clear info on how to do it. Only later did he see a clear picture and by then had forgotten how he'd done it.

Since the Aerodyne manuals have shown a clear drawing for at least the last 2 years, he probably wasn't working off a manual. He may have had vague or misinterpreted verbal instructions.

I seem to recall that Aerodyne ships gear with almost no paperwork, just a CD of manuals.
The lesson is a simple one about reading the effing manual if one isn't absolutely sure about something potentially critical.

That's why it's SOOOOO important to contact the manufacturer and ask the stupid question and get the correct answer.

“The only fool bigger than the person who knows it all is the person who argues with him.

Stanislaw Jerzy Lec quotes (Polish writer, poet and satirist 1906-1966)

[mjosparky 3]

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I was in contact with the rigger. He said it was the first time he assembled those type links and had a tough time getting clear info on how to do it. Only later did he see a clear picture and by then had forgotten how he'd done it.

That boy needs to be talked to and have some things explained to him. Rigging is never a "thats good enought" thing. Do it right or don't do it at all.

My idea of a fair fight is clubbing baby seals

[rushmc 18]

I was using a new rig to teach rig assembly at a riggers course. It was a SMART reserve that came with the ring type soft links. For some reason there were no instructions. (I was working with another rigger during all the following) So, being in a class we told the canidates that we did not know for sure how the links worked, we had the course owner go to his computer and download the instructions. We told the class that we would double check the instulation with the instructions when we got them and then continued.

Well, we put them on the same way you described (which was wrong) and when we got the instructions we went over them with the class. we pulled the risers out, gave a pull and the links came apart

Needless to say, the class got a good second lesson on using the book and/or instruction and the other rigger and I got good re-enforcement on the reason book/instructions are used.

The reason I return to help teach the call every year is I continue to learn and it is fun helping people get thier ticket.

"America will never be destroyed from the outside,
if we falter and lose our freedoms,
it will be because we destroyed ourselves."
Abraham Lincoln

[linestretch 0]

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That boy needs to be talked to and have some things explained to him. Rigging is never a "thats good enought" thing. Do it right or don't do it at all.

I think we all feel the same, but we don't need the riggin nazi police to get all wound up. PChapman said he already talked to the guy and it's been settled.

This is a learning experience for me for sure. After reading this, I re-opened a reserve I did a few days ago to double check, and then found a main that was connected wrong.....and jumped that way for a long time. Remember we are ALL human. I'm sure even you have made a mistake a two. Negative attitude about giving someone a talking to will just move more readers to NOT post learning experiences.

my pics & stuff!

[mjosparky 3]

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I'm sure even you have made a mistake a two.

Of course you are right, I have made my share of mistakes. Like you said we are all human. But this was not a mistake. It was not knowing how to do something and doing it any way. That to me is being very cavalier with someone else’s life.

None of us have all the answers but all the answers are out there if we take the time to look for them. That’s why forums like this can be such an important tool in receiving and passing on information and methods that will help us improve our rigging. With today’s instant communications there is no excuse to not take the time to find out something as simple as how to install a set of soft links. And this was a reserve we are talking about. If you feel that my being more than a little up set about something like this is a “negative attitude” then I guess I am guilty.

My idea of a fair fight is clubbing baby seals