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Marksman

Skyhook & RSL's. Its up to you....

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In this incident, the Collin's Lanyard didn't function as you describe because all of the velcro that holds the RSL lanyard to the rig (that normally the reserve pilot chute would be pulling against before it loaded the Collin's Lanyard) had been peeled by the opening forces when the stitch pattern failed. This allowed the piolt chute to load the left side cutaway cable (which may have been somewhat dislodged during the deployment) and cut the left riser away at ~200-250'. I hate to "monday morning quarterback" this jumper's actions since they obviously worked for him and were the right actions IN THIS CASE, but standard EP's would have been to either ride in what he had, or immediately deploy the reserve. His reserve was already deployed and ineffective due to the seal thread holding the hook to the RSL lanyard. So it was either ride in 1/2 a main or gamble with his life and cutaway.

No other system gives the reserve pilot chute the ability to cutaway 1/2 of the main parachute, and the force required to break the seal thread should certainly not be higher than the force required to extract the cutaway cable. I don't think a hook is the ideal design for a MARD due to the nature of the environment that it needs to operate in. Premature releases WILL happen. To counter that, a seal thread tack was added, which sacrifices the ability of the reserve to deploy at speeds where it would normally deploy. This creates a new set of EP's in some situations that aren't widely discussed.

I pay close attention to the Skyhook because I'm not convinced that the level of main/reserve integration that it has is a good thing. How many incidents have there been in the past 10 years where a standard RSL was implicated as a contributing factor?





If the Velcro is loose enough that the rpc is pulling that taught I hope one would notice that after opening. Students, as is situation may not, but if it was a experienced jumper I hope so.

I agree its not a perfect system but it has benefits if the jumper knows the ups and downs and what types of jumps to use/not use it for based on their thoughts and risk vs gain. its all personal choice unless your a student in which case the skyhook and/or rsl is there because the dz feels its more beneficial than not as students may panic and not pull the reserve handle, you never know

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This thread is getting interesting. I appreciate this added perspective. I remember alot of the debates on collins-lanyards and the reasoning's ascribed to/behind them specifically; and now, of course, their adaptation to and applicability (or maybe even NON-applicability or appropriateness) in/towards a MARD system or environment. At one point, risers being (supposedly) engineered maybe, as even a "fail safe" point to the H/C system. Meaning, that it is (or could be, arguably) better for a riser to fail/break, upon an extremely hard opening, or opening shock level that otherwise might have caused catastrophic damage to either the "core" H/C, or worse yet - the jumper him/herself. So, we "engineer" for that perspective/prospectus. Thus (in part) the reasoning (or at least one of 'em) for the collins lanyard.

Now comes along the skyhook. Is the collins lanyard appropriate application to/for/with it? Mandatory some may say? Completely NOT, and maybe even inappropriate altogether too, I've heard others say!

I'm not smart enough personally, to discern the difference.

I've seen several "hook" variants now, and observed some of their installation(s) on several different H/C systems 1st-hand. They ALL only seem to be "added"/add-on's to each of them. Meaning, "layered engineering" (with unintended/unanticipated potential new consequences exposure created on each) being applied. All possibly even good "concepts" in of themselves, ...but always (and in such varying) COMBINATION with one another? I dunno.

I don't think the average jumper even considers any of this. Rather, always simply opting for the latest "gadget", or "bell & whistle" that to them, SEEMS "cool".

I'm not so sure that entire system(s) considerations (like for instance - strengthening risers/rings/release failure points, versus the opting for collins-lanyards systems being needed to address them) might maybe need to be a part of a more fully appropriate, comprehensive (MARD) system, yet to be still "evolved"/deployed.
coitus non circum - Moab Stone

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If the Velcro is loose enough that the rpc is pulling that taught I hope one would notice that after opening. Students, as is situation may not, but if it was a experienced jumper I hope so.



I don't think that in the case being referenced and talked about here (the one from the video linked) had anything to do with the velcro being too loose - as much as it did with an inappropriate stitch pattern/application on the container itself failing, and it pulling the whole container off of the harness enough, to peel the RSL from its velcro, and load the collins lanyard prematurely/out of sequence.

Upon opening/hard-opening especially, would an experienced jumper have noticed this (that the RSL appeared separated from the velcro and is being "stretched" / under load - or that the container itself appeared damaged)? - - - Maybe? - Probably? And then, what would they have done about it? ...Do you know what you would have then done/responded before you got down to it's final failure (or riser-release by the collins-lanyard) point as is shown in this video? Would this have happened in the absence of a collins-lanyard being in place (rhetorical question)? - I think that is Kelly's point.
coitus non circum - Moab Stone

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...Do you know what you would have then done/responded before you got down to it's final failure (or riser-release by the collins-lanyard) point as is shown in this video? Would this have happened in the absence of a collins-lanyard being in place (rhetorical question)? - I think that is Kelly's point.




Its a valid point. Personally ive had my velcro come slightly loose (nearly pulling the velcro all the way off) a few times after regular openings in which my finger caught just the slight opening between the rsl and the riser just right when pulling the slider rings down and sometimes it just works its way out of the little stow so its a bigger snag issue.


Its going to take a significant amount of pull on the velcro even after its undone to pull that cutaway cable loose, especially if isnt cut so short that it barely is in the housing. If the cable isnt routed through the colins lanyard that issues eliminated and it may be for the better not to use it, but thats got to be a rig specific set up as the jumper wants it. Thats the beauty of having options.

You can set it up so your happy!;)

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I don't think that in the case being referenced and talked about here (the one from the video linked) had anything to do with the velcro being too loose - as much as it did with an inappropriate stitch pattern/application on the container itself failing, and it pulling the whole container off of the harness enough, to peel the RSL from its velcro, and load the collins lanyard prematurely/out of sequence.



That makes more sense then the way I was visioning it

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I'll need to make a decision re RSL/Skyhook in coming months, and I have to admit I find this thread interesting but confusing at the same time. My gut feel is to go with the skyhook (newer system) for the (a) additional time you'd have under canopy to setup your landing and (b) I understand it's more foregiving in terms of having to be completely stable upon reserve deployment.

Is there any published data re incidents/accidents associated with RSL versus Skyhook to give some sort of quantitative indication of relative saftey improvement for each? (perhaps there's not enough skyhook data yet?) I'm not sure exactly how you would compare the stats, however wouldn't it need to include the sum off effects from:

* (+ve) low deployment incidents under X feet for non-skyhook (i.e. that skyhook could have helped avoid incident)
* (-ve) skyhook induced incidents (if any exists)
* (+ve) RSL induced incidents
Parachutist Game IOS Android YouT

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No data that I have seen other than whats on UPT's website and the forums here and what you can learn around the dz. Read up on it for sure.

There are incidents involving both the rsl and skyhook, but there are many more incidents of cutaways without getting a reserve out in time.

It benefits you definetly as a new jumper flying a larger docile canopy, but can become less advantageous as you fly a smaller highly loaded canopy, but there are quite a few people that have no linetwists after cutting away with it on high performance canopys and there are those that end up with them. Time saved may or may not be worth it in different peoples eyes, but if for some reason I struggle to chop because of high g forces with a spinning mal I want something out sooner than later. Watch the video on upt's site its informative

Ive seen two personally from the ground under 1000 feet, per the pilot and all of us watching, that were under their reserve by 750 toggles in hand. Not the best idea to fly to the main and do that in traffic because you have a broken line and would rather have the main close to the dz though. Make that choice high skyhook or not, i guess thats faith in it though for that pilot, id rather not test that unless it was last resort to do so there

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Guys, thanks for all the responses! Indeed a very high level discussion going on, with lot of experience being brought to the table, please do continue.

Call it coincidence but after I started this thread, this happened... last week week my cousin joined me to the DZ, It was his first tandem. I exited first and they (tandem) followed, I got to watch their deployment and witness the spinning mal/tension knots situation that was promptly addressed by the tandem pilot's EP actions, the main was released and I saw first hand the skyhook performing its job pretty well, they landed correctly in safety.

:o Ufff, I took a breath again... Moments later I met them in the ground, my cousing was with a ear-to-ear smile, saying he wanted to do it again, at the beginning he did not even realized a disconnection had happened until the tandem pilot told him. After seeing the video, he still wants to go again. :S:D:D

I mean, clearly this kind of technology is here to help improve safety (doesnt matter the manufacturer's name or how many variations of the working principle might exist)...

The debate about adoption rate vs mindset/change resistance vs effectivity vs adaptability, is very valid but it's of great importance to address the fact that humans have a tendency to settle and use the least effort route...

Would we still be listening to casette tapes instead of ipod's if the sound quality was just okay and didnt need improvement or having less bulky players??

would we still think that airbags are a bad technology after the reports of world scattered events of kids/babies getting hurt? what about the saved people? the technology got adjusted, new sensors, new requirements, etc..

Maybe the fact is that canopies are working pretty well, containers too, AAD's are here to assist, people are still kind of screwed up ;) but we manage right? Bad decisions are now the main cause of incidents in this sport....have we already gone too deep into the confort zone?

So regarding decisions, when have skydivers decided that the development of technical advances in skydiving equipment has reached a plateau in the name of simplification?... what about the potential of criteriously adding more active safety?
The skydiving equipment industry is very sensitive to reputation, customer feedback and word spreading, is this something that collaborates with the plateau effect?

cheers!
Marksman.

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Guys, thanks for all the responses! Indeed a very high level discussion going on, with lot of experience being brought to the table, please do continue.

Call it coincidence but after I started this thread, this happened... last week week my cousin joined me to the DZ, It was his first tandem. I exited first and they (tandem) followed, I got to watch their deployment and witness the spinning mal/tension knots situation that was promptly addressed by the tandem pilot's EP actions, the main was released and I saw first hand the skyhook performing its job pretty well, they landed correctly in safety.

Ufff, I took a breath again... Moments later I met them in the ground, my cousing was with a ear-to-ear smile, saying he wanted to do it again, at the beginning he did not even realized a disconnection had happened until the tandem pilot told him. After seeing the video, he still wants to go again.

I mean, clearly this kind of technology is here to help improve safety (doesnt matter the manufacturer's name or how many variations of the working principle might exist)...

The debate about adoption rate vs mindset/change resistance vs effectivity vs adaptability, is very valid but it's of great importance to address the fact that humans have a tendency to settle and use the least effort route...

Would we still be listening to casette tapes instead of ipod's if the sound quality was just okay and didnt need improvement or having less bulky players??

would we still think that airbags are a bad technology after the reports of world scattered events of kids/babies getting hurt? what about the saved people? the technology got adjusted, new sensors, new requirements, etc..

Maybe the fact is that canopies are working pretty well, containers too, AAD's are here to assist, people are still kind of screwed up but we manage right? Bad decisions are now the main cause of incidents in this sport....have we already gone too deep into the confort zone?

So regarding decisions, when have skydivers decided that the development of technical advances in skydiving equipment has reached a plateau in the name of simplification?... what about the potential of criteriously adding more active safety?
The skydiving equipment industry is very sensitive to reputation, customer feedback and word spreading, is this something that collaborates with the plateau effect?



I don't understand the argument that you are making here regarding safety with skydiving gear. There is a lot of technology that is here to improve safety but it doesn't mean it that it should be adopted. I had one tandem mal and the skyhook didn't do its job and was pretty much like it wasn't there. I doubt that many on the ground would have been able to tell the difference between that and a normal rsl deployment.

Your association/argument is completely invalid in regards to this. I understand that it is a form of advancement in technology but as far as I know iPods aren't considered a safety device.

It regards to airbags. There is somewhat of a more valid argument. They are safety devices but there is also a lot more information and research that goes into car crashes. Regarding kids/babies getting hurt. They are outside the operating procedures of that device. That is why they are not to be subjected to them. While there seems to be a lot here it is a relatively small sample size and some of the numbers aren't as useful to people that analyze data. I have seen the argument be made that there are X many rigs with X equipment out there and they have done X many jumps. Well if the piece of equipment isn't used in any of those jumps than what does it matter? That is like having a home made camera mount that has huge snag points but since it never snagged anything it must be safe right?

I still don't see the huge amounts of safety that this device brings. You are making the system more complicated which leads to more issues that can arise. Having a canopy above your head doesn't necessarily mean that you will not be subject to injury but that is all that people think of. Look at the incident reports. People are dying under canopies. Further more if you were ever in a situation where you absolutely needed a MARD to get a canopy out above your head before impact with the ground. Do you think you would have the reaction skills and time to avoid any obstacles, find a suitable landing area, flare, etc.? You mentioned that bad decisions are the main cause of incidents in sports. Do you think that most people out there would be able to do all that is necessary and make the right decisions in a case were a MARD would give you the greater chance of survival (for example below 500 feet)? There are a lot more to this than just having a canopy above you quickly.

Just my $0.02.

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You would be just as safe. Except if you choose to cutaway at 300ft then the skyhook may get a reserve over your head if it stays connected and doesn't just turn into a normal rsl deployment. Which happens quite often really, even when installed and rigged correctly. A normal rsl pretty much has 0 chance of saving you from 300ft but it doesn't have all the added complexities and potential problems brought up in this thread. Plus its a standard option so it won't cost you extra.

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And... putting something in your gear, that makes anyone think it is OK to go ahead and chop at 300ft AGL, IMHO is also a grave mistake. [:/]



Who the hell thinks it's OK to chop at 300 ft?

The bottom line is that no one wants to chop that low and if you need to you've fucked up very, very badly to get there in the first place. But if you've got yourself that deep in the shit, you do whatever you think will give you the best chance of survival. With a skyhook you might survive a chop. Without a skyhook you might survive tossing your reserve into the bag of shit that is your main. You pays your money and you makes your choices.

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If you do it enough times there WILL be burst of air that throws your pilot chute around your foot,



This is one of the many scenarios the SkyHook was originally designed to avoid. With a standard RSL, your pin is pulled as your risers leave your body and your Freebag comes off of your reserve in 1.5-2 seconds regardless of your body position. It is possible that you are on your back and your Freebag deploys through your legs with the possibility of the bridle wrapping around your leg/foot.

Because the SkyHook puts your reserve where your main was, with a SkyHook deployment, it is very unlikely to become entangled with the cutaway canopy, Freebag, or deploying reserve.


Mark Klingelhoefer
United Parachute Technologies

Edited to add picture that was bigger than 250 kb

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You would be just as safe. Except if you choose to cutaway at 300ft then the skyhook may get a reserve over your head if it stays connected and doesn't just turn into a normal rsl deployment. Which happens quite often really, even when installed and rigged correctly. A normal rsl pretty much has 0 chance of saving you from 300ft but it doesn't have all the added complexities and potential problems brought up in this thread. Plus its a standard option so it won't cost you extra.


Wrong. It depends if your RSL is "single sided" or not. If you have an RSL that will pull your reserve pin without making sure that BOTH risers have released first, then you could have major "complication". Personally, I wouldn't jump with a single-sided RSL.

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If you have an RSL that will pull your reserve pin without making sure that BOTH risers have released first, then you could have major "complication". Personally, I wouldn't jump with a single-sided RSL.



True. But I asked you before, I will ask you again. How is Collin's lanyard going to help if you don't have a load on the left side risers? The release cable will be out, but the riser will still be there and you still gonna have a possibility for a "major complication"
That's one. And second, how about the lanyard releasing the left side risers when not need it? (Chicago incident) It's a major complication as well, right?!

I think that the Collin's lanyard will save you from problems ONLY if you have a broken RSL side risers on opening. Thumbs up for that. Now the question is how many correctly made and in good shape broken risers you have seen the last 10 years?

The truth is, what might save you in one situation it might kill you in another.

And one more question. How many reports do you have from the field where Skyhook didn't work as MARD? I have seen 6 chops with a Skyhook. in 2 of them ( spinners) the Skyhook disconnected before it pulled the freebag out of the rig. And I have seen some other videos with the same outcome. What is the real ratio of Skyhook not performing as a MARD?


As for the personal preference, you will not see me or my girlfriend jumping a Skyhook equipped rig.
"My belief is that once the doctor whacks you on the butt, all guarantees are off" Jerry Baumchen

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You don't need a "broken" riser to have a problem. A miss-rigged riser or flipped-down riser will cause an accidental release of one riser too. I have at least three videos of flipped-down risers where the Collins' Lanyard saved the day, and report of many other cases, in just the last few years.

By the way, the split lanyard update of several years ago on the Skyhook makes a North Carolina type accident even less likely.

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flipped-down riser will cause an accidental release of one riser too. I have at least three videos of flipped-down risers where the Collins' Lanyard saved the day, and report of many other cases, in just the last few years.



I've seen flipped risers on the packing floor many times. What I'm surprised to hear is that a "supervised" packer will pack it this way and a so called TM will gear up, board the plane and then jump without checking himself or without the problem being spotted by the video jumper.

I hope that they have sent you a bottle of your favorite drink together with their TM rating.
"My belief is that once the doctor whacks you on the butt, all guarantees are off" Jerry Baumchen

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I totally agree with Bill Booth (a first) that if you are going to use an RSL it must be a “Double Sided RSL”. However, some facts must be made clear about the history and development of the RSL before we can make an informed decision about the subject.
The U.S. Navy (before Piggy Backs) required a cross connector on the main risers if a cutaway was planned for dealing with a mal. The reason was that the sudden acceleration when one side releases might prevent disconnecting the other side because of the complete loss of any drag you might have had.

Perry Stevens created the Stevens System RSL for conventional systems. It had a cross connector at the connector links of the riser on both the front and rear risers and a lanyard from the right riser to the chest reserve ripcord. Guaranteed to remove teeth as it activated the reserve.

When piggybacks came out Para-Flite put a cross connector on the Swift. A navy test jumper at El Centro had a mal on a Swift and the X-conn caught under the reserve container jamming the reserve preventing its deployment. He rode this to the ground and survived because the main still had some drag thanks to the x-conn holding the risers from completely spreading and going streamer. I have seen and studied the video.

We had anticipated this problem and had in fact advised against the design. However we all recognize the need for a x-conn which is the foundation for the “Double sided RSL”. A double sided RSL which does not have a x-conn is a giant risk, as releasing one side might cause complete loss of drag. Any RSL needs a x-conn.

For Piggy backs there is only one which has a x-conn. It is located at the base of the risers where they attach to the harness. It has over 30 years in the field and the rap on it was by unthinking folks who panic when they have a 2 out situation. “It will choke the reserve when you cutaway the main” they shouted. Not realizing they had reduced their descent rate to an acceptable level. They were afraid of a personal down plane which might occur temporarily during deployment but will naturally come to a side by side or bi-plane because both canopies are facing the same way if they are attached to the harness correctly. To have a down plane they must face different directions. Additionally, some folks worried it might hit them in the back of the head or knock off their helmet. Whoopie!

Now that we have established the need for a x-conn why not use it to pull the reserve ripcord? We did. This design provides for no automatic reserve ripcord pull until both side release.

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Does a flipped down riser release because it breaks?


It breaks the white looking loop


Pardon my ignorance, but what is a 'flipped down riser'? How does it arise?


Yeah, what he said: "what is a 'flipped down riser'?" (a search of the forum using that phrase didn't answer the question.)

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Does a flipped down riser release because it breaks?


It breaks the white looking loop


Pardon my ignorance, but what is a 'flipped down riser'? How does it arise?


Yeah, what he said: "what is a 'flipped down riser'?" (a search of the forum using that phrase didn't answer the question.)



I believe it is when the large ring on the riser is out of position - pushed down in the way that it kinda feels like it is jammed in the harness ring. The mechanism still works (it will release if activated), but the forces on the white loop are very high because the geometry is now different putting much higher forces on the loop.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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