hackish 8 #1 March 3, 2015 This morning I started noticing that all of our tandem main soft links are in bad shape. All have been installed for several years. Last year a few started catching my eye as items to watch. They've progressed from "Hmmm" to "must replace". Is this something others have seen before? How many DZs are using the SR-1 soft links on their mains? Is there a solution that could protect them and still allow easy inspection? -Michael Quote Share this post Link to post Share on other sites
jumpsalot-2 2 #2 March 3, 2015 At $40 a pair, why would you hesitate to change them every year ?Life is short ... jump often. Quote Share this post Link to post Share on other sites
hackish 8 #3 March 3, 2015 If in 1 season enough damage can occur to cause a piece like this to become damaged then my first objective is to stop the damage from occurring. I'll get some photos but I am pretty sure it's from heat. -Michael Quote Share this post Link to post Share on other sites
skydiverek 58 #4 March 3, 2015 Read from THIS post, down: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3329635#3329635 Quote Share this post Link to post Share on other sites
BrianM 1 #5 March 3, 2015 Interesting timing to bring up this topic - shortly before I saw this, I received a Technical Bulletin from CSPA on the topic of soft links on tandems (as a CSPA rigger I'm guessing you have or will receive it too). Here's the relevant excerpt: QuoteUPT does not approve the use of soft links of any kind on the tandem mains or reserves. UPT has found melted slinks and main risers due to heat development from friction between the slider and lines. Also, the T4 slider bumpers are required on the Vectran line sets. The CSPA T&SC also found damage to the slinks on tandems equipped with them, during the Rigger A1 course last year. I haven't looked up the relevant info in the UPT manual yet but I'll take a look when I have a few minutes. I don't have any personal experience with the issue, my DZ has metal links on our tandem mains and reserves."It's amazing what you can learn while you're not talking." - Skydivesg Quote Share this post Link to post Share on other sites
Beatnik 2 #6 March 4, 2015 The technical bulletin is slightly misleading and this has been an issue with UPT tandem systems for a while. It mentions soft links on reserves as well in the main line. On the Sigma system if one was going to install soft links they would have to pick out stitching from the reserve risers as they are sewn to accept L-bars. This issue was brought up when I was on the tandem examiner course several months again. According to CSPA's technical bulletin, they claim Rigger A's can do the repair. The issue is greater than damage to main risers or soft links and there should be a bulletin reflecting accurate information and address the larger issue of the reserve risers. On a personal note I don't care about the mains as they aren't certified anyways and if people want to do unapproved things to that part of the system it is pretty hard to stop them. Plus while it does state it is for UPT canopies, meaning Sigma canopies, I think it was overlooked. The bulletin doesn't apply if there are Icarus or Aerodyne mains used on the Sigma system. Quote Share this post Link to post Share on other sites
hackish 8 #7 March 4, 2015 Interesting coincidence that there was in fact a CSPA technical bulletin did just come out about this. -Michael Quote Share this post Link to post Share on other sites
BrianM 1 #8 March 4, 2015 BeatnikPlus while it does state it is for UPT canopies, meaning Sigma canopies, I think it was overlooked. The bulletin doesn't apply if there are Icarus or Aerodyne mains used on the Sigma system. I thought it was unclear whether it was referring only to UPT canopies, or to UPT rigs in general. The language is a little odd in a couple places: "UPT does not approve the use of soft links of any kind on the tandem mains or reserves" (emphasis mine). If the italicized "the" had said "their" I would agree with you. It is an awkward phrase with "the" in it, and sounds like something that was poorly translated from another language, so I looked at the French version: "UPT n’approuve pas l’utilisation des ‘soft links’ sur aucune voilure de réserve ou principale de ces équipements Tandem sigma et micro sigma." which is much clearer! No soft links on any main or reserve on Sigma tandem equipment. The other odd phrase was "Ensure all UPT tandem chutes and equipment are rigged IAW manufacturer’s instructions only". What does "and equipment" mean in this phrase? I suspect it's referring to the harness/container. This time the French version, while better written than the English, also doesn't make the distinction: "S’assurer que tous les Tandem de UPT sont assemblés selon les normes du manufacturier." Ok, follow manufacturers instructions, great - but the Sigma manual doesn't discuss links at all, nor do any UPT service bulletins. If UPT has found damage to risers, not just lines, I could see them not approving soft links on rigs regardless of the canopy, and I think that was the intent of the TB. According to previous threads on dropzone.com, UPT doesn't allow them on their rigs at all - and after seeing photos of riser damage that have been posted, I think it would be wise to stick with metal links. It would be nice if UPT actually said that somewhere that riggers could find it."It's amazing what you can learn while you're not talking." - Skydivesg Quote Share this post Link to post Share on other sites
pchapman 262 #9 March 4, 2015 Following on to what you have discovered about CSPA Technical Bulletin #110, if the English and French are confusing and don't match each other, then can one trust either version to be the true intent? It would indeed be nice if a bulletin actually referenced the manufacturer's statements/manuals/bulletins to back up its claims. The CSPA bulletin shows how hard it is to write a bulletin truly accurately! Quote Share this post Link to post Share on other sites
reactor 1 #10 March 4, 2015 last year, when i ask UPT about vetran line icarus tandem/soft link on sigma system. this is what i got from them Upt does not allow soft links on tandem mains or reserves. Here are a few pictures where the grommets got hot enough coming down the lines to burn the risers. You can pass these pictures on to anyone you like. Thanks, Mike Maguire Quote Share this post Link to post Share on other sites
riggerrob 561 #11 March 4, 2015 Bottom line: UPT has learned (the hard way) that soft links are not durable enough for tandems. Smart riggers take UPT's experience as "best business practice." Icarus tandem canopies come stock with metal links. Next tandem canopies come stock with metal links. The last time I jumped a Parachutes de France tandem canopy, it had metal links. PD tandem canopies come stock with metal links. Precision tandem canopies come stock with metal links. Racer tandem canopies come stock with metal links. Strong tandem canopies come stock with metal links. According to PIA Technical Standard 102, the canopy manufacturer is responsible for supplying connector links. Quote Share this post Link to post Share on other sites
Beatnik 2 #12 March 4, 2015 I discussed this issue in person in December when I was at the factory for a week. There is a lot more to it than the technical bulletin described. I emailed the chair of the TSC along with my BoD member and the CSPA office giving more information regarding the issue since I have a close relationship with UPT and was told by the TSC chair that it was good enough and it was their information that was distributed. I know for a fact that is completely inaccurate and am disappointed to see the direction things are going with the CSPA rigger program and TSC. But I won't get into that here. The other issue discussed during this is that the main system is uncertified and doesn't have the same control that the reserve system has so they can really only state with the components that are approved with their system. They know as well as a lot of us here that there are many rigs out there that don't have Sigma main canopies. At the end of the day if people want to use soft links on their tandem main and damage the main risers, it just creates more revenue for UPT. The technical bulletin should be amended as it fails to capture the real issue and gives inappropriately rated riggers the ability to repair issues that they aren't able to do. Talking only in regards to the issues with reserve risers I mentioned previously and not the issue with the main parachute components. Quote Share this post Link to post Share on other sites
parachutist 1 #13 March 5, 2015 riggerrobBottom line: UPT has learned (the hard way) that soft links are not durable enough for tandems. Smart riggers take UPT's experience as "best business practice." Icarus tandem canopies come stock with metal links. Next tandem canopies come stock with metal links. The last time I jumped a Parachutes de France tandem canopy, it had metal links. PD tandem canopies come stock with metal links. Precision tandem canopies come stock with metal links. Racer tandem canopies come stock with metal links. Strong tandem canopies come stock with metal links. According to PIA Technical Standard 102, the canopy manufacturer is responsible for supplying connector links. Icarus mains were coming stock with soft links a year ago. Has that changed? I install used Sigma ty-4 bumpers to protect the links and risers in this config. They're stiff enough to keep the slider up and off the goods. Quote Share this post Link to post Share on other sites
riggerrob 561 #14 March 5, 2015 ........ Icarus mains were coming stock with soft links a year ago. Has that changed? I install used Sigma ty-4 bumpers to protect the links and risers in this config. They're stiff enough to keep the slider up and off the goods. ...................................................................................... The last batch of Icarus tandem mains that I worked on had Maillon Rapide connector links. They were manufactured a few years ago and had been re-lined (outside the factory ) more than once. Quote Share this post Link to post Share on other sites
hackish 8 #15 March 5, 2015 Thanks for the pics reactor. We have no damage like that so far. It also appears in those pictures that there is a rapide link installed as I think you can see the barrel. I am curious how related is this to the actual line material. Is it specific to dacron lines? Are there specific types of sliders that cause it more than others? Is the type of grommet related? Of course brass will conduct heat better but probably also generate more than let's say SS. -Michael Quote Share this post Link to post Share on other sites
reactor 1 #16 March 5, 2015 i think that UPT try to say is grommet are hot enough to melt riser, so it could melt soft link too if grommet stop at soft link. i don't have answer for your question. you should ask UPT, they are very helpful, also please share to us here if you do get some useful information. Quote Share this post Link to post Share on other sites
TomNoonan 1 #17 March 5, 2015 Here is a picture of a brand new Sigma riser, less than 20 jumps, melted from grommet on a riser with Slinks on the main. This is an example of almost immediate damage to an expensive component.Namaste, Tom Noonan www.everest-skydive.com Quote Share this post Link to post Share on other sites
parachutist 1 #18 March 6, 2015 TomNoonanHere is a picture of a brand new Sigma riser, less than 20 jumps, melted from grommet on a riser with Slinks on the main. This is an example of almost immediate damage to an expensive component. Clearly a slider bumper should have been used to separate the grommet from the link and riser. That's all that comes to mind when I see these pictures. Am I missing something? Chris Quote Share this post Link to post Share on other sites
skydiverek 58 #19 March 6, 2015 parachutist***Here is a picture of a brand new Sigma riser, less than 20 jumps, melted from grommet on a riser with Slinks on the main. This is an example of almost immediate damage to an expensive component. Clearly a slider bumper should have been used to separate the grommet from the link and riser. That's all that comes to mind when I see these pictures. Am I missing something? Chris Where would the heat go then? To the lines (all in one place). Quote Share this post Link to post Share on other sites
parachutist 1 #20 March 6, 2015 Quote Where would the heat go then? To the lines (all in one place). Whether hard or soft links are used; the parachute, slider, bumper, and lines are the same in both cases. So the same heat gets generated, and those grommets rest in the same place in both cases: about 2" above the links. I have no desire to actually use soft links on tandem mains because they'd need to be replaced every reline. Paying for SS links once seems more reasonable. I'm just saying the melted risers seem like a non-answer to the question because there's already a solution available to that issue. Quote Share this post Link to post Share on other sites
