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Jeffrey

Riggers and non riggers poll #4, this one is for every one.

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Background to this Poll:
Over the past 10 years I have had a total of 3 broken T-17 risers reported and returned to me. Every one of them was the right rear section only, ripped cleanly through the confluences wrap from the grommet up. I personally think this was a very good thing and in every case, the riser broke for a very good reason. For example; 330 + out the door is a little much to ask of T-17 risers. There are also other reasons they broke where they did. ;)

The only rule of this poll is that it applies only to risers manufactured by companies producing TSO’ed equipment manufactured in the last 7 years.

As a reminder to the 2 participants that voted in my last poll, that would NOT like to see more. We all appreciate you not participating again and thank you for it.

Once again thank you for your honest participation.

Edited to add: I just noticed a typo, the very last line in the poll should have read, “The riser I have seen that broke was the left one below the grommet.” Sorry

Jeff

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sunpath risers, less then 50 jumps, SA2 190, less then 50 jumps, 220 lbs exit weight, right rear riser. Very similar to 0825, except the area between the grommet and wrap was damaged.

(very) Unstable deployment, big guy. Lifeflight, 3 weeks down, no lasting injury.

I have a set of risers in the loft that are ready to do what happened in your pics if you want a "before" pic.

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Lee,

Wow, I haven’t seen or heard of them breaking there since the 90’s and that was because they were made of ¾” type 3 binding tape. Most companies including us use 5/8” type 4 square weave (very tuff stuff), some company’s use 1” type 3 binding tape to hold the top RW4 ring. I can see where the type 3 tape could be a weaker link in the chain depending on how it is sewn at the center bow tie section. Do you have or can you get any photos? The only way I can see where one with the type 4 could brake is if it had been previously damaged or is way out of spec.

I can easily see where the front riser could be the one to go as well. Most of the risers I have seen that’s been subjected to heavy loading first show signs of fatigue at the grommet.

Floormunky,

Please do, post photos of them if you have them. I see that stuff all the time but it would be good to share with this thread.
Glad to hear he’s going to be ok. When risers are subjected to loading that high, you know the body is getting hammered. The riser in photos 821 and 822, the jumpers ended up with leg and chest bruising. One got black eyes on top of that. Both still was able to cutaway and get a reserve. The jumper in photo 825 was a very big boy and weathered the loads better.

Thanks for the replies guys.

Jeff

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Personally, I dont care much for the T-17 risers. I guess I like more material holding the load. That is from my military rigging exp. I guess.

I dont know of any cases of the T-17 coming apart in my personal exp. also I only know of a hand full of people who use them.

Only way I could see them coming aprat is too much stress in that area upon opening.. IE jumper turns to that side durning deployment and the shock is to that side.. Opening first more so then the uniform opening of both risers at the same time......

Just my personal observations......
Kenneth Potter
FAA Senior Parachute Rigger
Tactical Delivery Instructor (Jeddah, KSA)
FFL Gunsmith

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Thanks for sharing those pictures Jeffrey.

Would it make any difference if there was more bartack/zig-zag stitching (E Thread) between the grommet and the top edge of the confluence wrap?
... or would that just make it too fat to sew the confluence wrap?

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Would it make any difference if there was more bartack/zig-zag stitching (E Thread) between the grommet and the top edge of the confluence wrap?
... or would that just make it too fat to sew the confluence wrap?


Hi Rob,

Yes I think it would make a big difference by bonding the loosely woven T-17 webbing together and make it stronger, we would have no problem sewing it. But is this what we really want? I have spent many years observing T-17 risers that have been subjected to undesirably high loads and the stronger you make them in one spot; they will always break in another. Not knowing where they may break next makes me very uncomfortable. What else makes me uncomfortable is if I make them stronger in that spot, now the jumper and canopy will be getting that extra hammering in these rare occurrences.

I could expand much more on this portion alone but will leave it here for now.

Thanks for your thoughts.

Jeff

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Airtwardo,

I’m sure it left a mark and probably would have been worse on the body if they were reinforced.

You don’t have to say, but who made those riser? Please tell me they weren’t manufactured by a company producing TSO’ed equipment in the last 7 years. I see fare to many things wrong with them.

Jeff

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I have never seen a T17 break but I have seen tandem riser break. It was the rsl side and the rsl was disconected. Broke just above the gromet. Goog thing the rsl was disconected
"America will never be destroyed from the outside,
if we falter and lose our freedoms,
it will be because we destroyed ourselves."
Abraham Lincoln

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Airtwardo,

I’m sure it left a mark and probably would have been worse on the body if they were reinforced.

You don’t have to say, but who made those riser? Please tell me they weren’t manufactured by a company producing TSO’ed equipment in the last 7 years. I see fare to many things wrong with them.

Jeff



Not so much a mark ON the body as IN...upper right leg and lower hip internal ouchie...left riser was the one broke.

It wasn't my rig but one I was jumping on a demo, my understanding is that the gear is about 9 years old and has less than 500 jumps.










~ If you choke a Smurf, what color does it turn? ~

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Not so much a mark ON the body as IN...upper right leg and lower hip internal ouchie...left riser was the one broke.

It wasn't my rig but one I was jumping on a demo, my understanding is that the gear is about 9 years old and has less than 500 jumps.



Thanks airtwardo,

I haven’t ever had a riser fail, but the hardest opening I’ve ever had was on a demo rig with a GQ Unit packed by only God knows who back in the very early 80’s. Apart from seeing stars, the only thing I remember was my Alt II centered on the chest strap and all the blood running on and off it. I was young and could take a punch in the face by an Alt II back then but never centered it on my chest strap again. That was in Z-Hills (next to the golf cores days).

Sorry to get off topic there and to bad I have plans for my next poll already. Hard openings could be good one, I’m just note sure how I could make it educational.

Jeff

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What kind of material does Infinity use to hold the small ring. I really like the design of the infinity risers but they use a thinish style webbing for the little ring. Anyone know how strong that type of webbing is?
- - -
I am not afraid of tomorrow, for I have seen yesterday and I love today.

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I've known of at least two of them that failed. Both were the older un-reinforced Type-17 mini risers. And both were TSO'd. One failed on a B.A.S.E. jumper at Half Dome in Yosemite and what saved him was the riser caught in the slider and the canopy spiraled him in instead of just dumping him in.

The other was a skydiver at Lake Elsinore and it killed him after an out of sequence EP.

Neither broke at the rear leg where pictured. They both broke where the grommet was. If you think about it, after punching the hole and installing the grommet the only thing left holding you is the bit of material on either side of grommet. Otherwise these are rated at, I think, 2500 pounds, but once you put a grommet in, it's nowhere near that. This is why the newer Type-17 risers are reinforced in that area.

I can see where Type-17 risers are good aerodynamically for swooping and such, but if you aren't doing that what's the point? You can still use the fatter Type 8 risers with mini-rings. It reminds of something the late Al Frisby (I'm still not used to saying that) said, "These idiots, they swap out their steel connector links for Slinks to save weight, then they strap on lead to jump."

NickD :)BASE 194

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What kind of material does Infinity use to hold the small ring. Anyone know how strong that type of webbing is?



MIL-T-5038, 1" Type III, Binding tape, 525 lbs.

Jeff



Do other/most manufacturers use this material for the small ring?
- - -
I am not afraid of tomorrow, for I have seen yesterday and I love today.

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Hi Nick,

Quote

And both were TSO'd.

I know of no main risers that hold TSO certification. Yea, I know; nit-picking. ;)

As for how others make risers; I think the only mfr who makes their risers exactly as per the 3-ring instructions ( available from UPT ) is UPT themselves. Almost everyone else has some change to them.

JerryBaumchen

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I've known of at least two of them that failed. Both were the older un-reinforced Type-17 mini risers. And both were TSO'd. One failed on a B.A.S.E. jumper at Half Dome in Yosemite and what saved him was the riser caught in the slider and the canopy spiraled him in instead of just dumping him in.

The other was a skydiver at Lake Elsinore and it killed him after an out of sequence EP.

Neither broke at the rear leg where pictured. They both broke where the grommet was. If you think about it, after punching the hole and installing the grommet the only thing left holding you is the bit of material on either side of grommet. Otherwise these are rated at, I think, 2500 pounds, but once you put a grommet in, it's nowhere near that. This is why the newer Type-17 risers are reinforced in that area.

I can see where Type-17 risers are good aerodynamically for swooping and such, but if you aren't doing that what's the point? You can still use the fatter Type 8 risers with mini-rings. It reminds of something the late Al Frisby (I'm still not used to saying that) said, "These idiots, they swap out their steel connector links for Slinks to save weight, then they strap on lead to jump."

NickD :)BASE 194



Nick,

I wanted to reply sooner but I often get overwhelmed with to many to do’s and there are many things I would like to explain and discuss regarding your observations and comments.

First being that the older style risers you mentioned both broke at the grommet. There is no question that the grommets hole is undoubtedly a week link, and in my opinion is a very good thing. Sadly, I still see those risers resurfacing often and would love to see them gone.

Back in the very early 80’s when I was building Warp III’s for National in Z-hills; I noticed that even though I seared the grommet hole in my risers, they still occasionally would pull out from the grommet. My fix was to put a bar-tack across the top and bottom of the seared hole. This bonds the loose weave fibers together and then will be trapped by the spurs in the grommet washer. That proved to an instant solution to that problem and was instantly copied and become the standard.

Now skipping forward to the early 90’S, a new problem pops its head up (I’m now employed by RWS at the time). Reports indicate that 1” T-17 riser's can break. Bill B. visualizes the potential problem that could be associated with 1”risers and RSL’s. As you know, we don’t want a broken riser to immediately deploy our reserve into the trash on the other riser per a RSL. Instantly a PSB was produced banning the use of RSL’s with 1” T-17 risers and its back to the drawing board on 1” T-17 riser construction.

Now since the introduction of 1” type III from many years ago, we not only get another 1000 lbs. at the grommet, but its tighter weave also helps bond and hold the loose T-17 tighter together with the bar-tacks. And as you very well know, we use the combination with RSL’s again. Since then I have been watching very closely. From what I have observed, the grommet is still our weak link but is far stronger than it was. It now really has to take a big hit before it’s ripped out from under the grommet. I feel comfortable knowing that the riser construction I use also serves as an indicator on the back side of the grommet and says a lot about the loads they have been subjected to. The best time to inspect them is every time you set your brakes.

Please don’t think I’m speaking in support of 1” risers, I couldn’t agree with you more that not every one really needs 1” T-17 risers. But unfortunately we have to supply the demand, and I would say we probably sell 98 percent 1” T-17 over 1 ¾” T-8. I try to stop it on a regular occasion when I notice we get orders for rental rigs or very large jumpers. And I still occasionally get resistance from the customer’s who insist on 1’ T-17 risers.

If aerodynamics is that big of a deal, there are other options. If anyone has seen the risers I built for Team Xtreme, many of those options have been available for some time and can be dune in type 8 as well. No one ever asks! Any Rigger with a zigzag can fold T-8 risers back and make them more aerodynamic.

Jeff

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It still amazes me that I have gotten complaints from DZ riggers that report finding webbing that has pulled out from the grommet on rental/student gear w/ T-17 risers and think that because it never happens on other sport rig’s from there experience, think all T-17 risers should always last thousands of jumps. Therefore it must be a manufacturing defect.

(HELLO) Read the dam manual about T-17 risers and think about it.

Jeff

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