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adamqbishop

RSL/NO RSL?

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Hi every one
I’m not normally that vocal about anything and most of the time I keep my opinions to myself but the other day I got my latest issue of “Parachutist” mag and as always the April issue has last year’s Fatality Summary by Paul Sitter. Now before I get too much into my opinion/issue, I want to qualify; I fly a sub-100 canopy with a little over 2200 jumps, hold an AFF instructor rating for 1 year, have been in the sport less than 5, have had 3 cutaways and my rigger has 3 saves obviously. So compared to Mr. Sitter I am still novice and that’s okay by me. In this latest issue, Mr. Sitter repeatedly acknowledges the pros for the use of an RSL even to the point of saying, “there would have been fewer deaths in 2011 if the jumpers had used one,” but only briefly acknowledges the cons. He fails to acknowledge that the jumpers who die, including the Tandem pair (Meaning TWO) and the ingle jumper whom experienced the main/reserve entanglement, most probably had an RSL that deployed their reserve before clearing the main. What I gathered from the report was only one jumper could not find her reserve handle before impact.

Now back to “MY” opinion/ issue, I don’t want people to think I am totally 100% against RSL’s because I am not. Student gear and jumpers who jump mains with less than a 1:1.5 wing loading I highly recommend them. But as you down size, line twists turn into spinning on your back and revolutions increase causing horizontal 360s upon release of your main, the chance for a double malfunction becomes a reality with the use of an RSL. I have found it better to get stable (belly to Earth), then pull the reserve and allow it to have the best chance of a good opening. All three of my cutaways were on a sub-100 canopy with line twists spinning on my back. My last cutaway was at 1800 feet, main deployment at 2500ft, and open under a perfect reserve by just taking that extra 5 seconds to get stable after spinning three rotations after my cut away.

Just so no one is confused, the RSL has saved many lives and I only express this opinion so as to give the whole story of the use of an RSL. I just want you to know that there are hazards to an RSL that are not mentioned. God Speed to those that have perished in our sport.

Adam Q Bishop
D-31570
Faster, Faster, Faster
Till the Thrill of Speed
Overcomes the Fear of Death

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and open under a perfect reserve by just taking that extra 5 seconds to get stable after spinning three rotations after my cut away.



Flaw in that.

Quite a lot of people, over the years have bounced as a result of trying to get stable. Generally speaking, it is a bad idea to delay after a cutaway.

A spinning mal can also induce a degree of disorientation resulting in a loss of awareness of altitude.

Although there ARE situations where RSL's can cause problems, and disciplines (like CRW) where they should not be used.

I think the point is, they will, over time save more than they kill.
My computer beat me at chess, It was no match for me at kickboxing....

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Mr. Bishop, the problem with the sensationalistic arguments based on rumors and second hand tellings about the cons of RSL's is that the simply are not backed up by statistics.

In 30 years I can count on one hand the number of fatalities influenced by the use of a conventional single riser RSL. The number of breakaway to no/low pull fatalities for the same period can be totaled over 50, perhaps 100.

First you must discount the dual sided Racer type RSL, as that design is flawed. It is more prone to fatal mis-rigging and can cause additional problems in dual deployments.

Second the wing loading/line twist on the reserve argument is weak at best since we havent seen droves of people spinning in under malfunctioned reserves. The reserve canopy TSO has standards of survivable decent rates WITH line twists.

The simple fact is RSL's saves lives, without adding any significant amount of risk.

I speak from practical experience as I have 34 breakaways from malfunctions and well over half are on RSL equipped rigs.
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You're not as good as you think you are. Seriously.

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My personal experience on moderately-loaded fast-turning (Diablo) with spinning line twists from a brake fire is that the reserve deployed clean with no line twists. The Diablo is noted for its fast turns.

Just to be sure (:P) I did it again 50-100 jumps later. Then I changed my brake lines (they were loose where the toggle locked it), and have had no further problems.

Wendy P.

There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

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Somewhere around here is a whole discussion about WHY line twists happen on reserve deployments including those deployed by an RSL. In the case of RSL deployments the twists are most often caused by the jumper's attempt to get belly to earth rather than place the body in the optimum position for a clean deployment in relation to the relative wind.

The moment after a break away the optimum position is NOT belly to earth, but rather feet into the relative wind.
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You're not as good as you think you are. Seriously.

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I fly a sub-100 canopy with a little over 2200 jumps ......have been in the sport less than 5 years



Sport death.

If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.
Chuck Akers
D-10855
Houston, TX

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Quite a lot of people, over the years have bounced as a result of trying to get stable. Generally speaking, it is a bad idea to delay after a cutaway.



Trying TOO LONG to get stable has killed people.
Trying to get stable WHEN TOO LOW has killed people.
That's why a delay after a cutaway in my mind could be considered an advanced maneuver, but normal & acceptable.

(Otherwise you might as well say that deploying your main is bad because it has killed people. No, trying too long to deploy your main kills people.)

Besides, many people have AAD's now, which somewhat reduces the need to think, to some degree replacing the RSL as a backup. An RSL or an AAD can help with the 'lost reserve handle' scenario that affects even experienced jumpers.

I've only done a couple chops but find the distance to go from an unstable no-RSL chop, to flipping to belly to earth, to having a reserve is about 700 ft (going from video & protrack). Not bad at all. It's only a couple data points though.

As for actual data, diablopilot, can you find that thread where you say the idea came up about trying to go belly to earth not being appropriate when one is using an RSL? It's hard to remember every RSL thread... It does imply that RSL's aren't as fast as some people claim -- not the perfect antidote to unstable chops.

I'm not so worried about reserve line twists. (Offhand, I thought they have injured or killed a couple people, but they were probably very low to begin with so getting more stable might not have been an option.)

I dislike the RSL cutaway stories about lines going past one's helmet, bridle across one's neck, that sort of thing. But I'm not sure how low those chances are. Unstable deployments are just not as good for parachutes, but the type of problem, frequency, and seriousness can be debated.

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:
Faster, Faster, Faster
Till the Thrill of Speed
Overcomes the Fear of Death

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:

I'll link to your reply in the incident forum. Hope you don't suffer long.;)
Chuck Akers
D-10855
Houston, TX

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:


I'll link to your reply in the incident forum. Hope you don't suffer long.;)

That's a pretty cuntish comment.

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:


I'll link to your reply in the incident forum. Hope you don't suffer long.;)


That's a pretty cuntish comment.

I'd tell you what I think of your comment but I don't issue opinion to people too chickensh*t to identify themselves.

No name, no respect.
Chuck Akers
D-10855
Houston, TX

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:


I'll link to your reply in the incident forum. Hope you don't suffer long.;)


That's a pretty cuntish comment.


I'd tell you what I think of your comment but I don't issue opinion to people too chickensh*t to identify themselves.

No name, no respect.

I don't really care about your opinion of me, but I wanted you to know my opinion of your comment. Mission accomplished.

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:


I'll link to your reply in the incident forum. Hope you don't suffer long.;)


That's a pretty cuntish comment.


I'd tell you what I think of your comment but I don't issue opinion to people too chickensh*t to identify themselves.

No name, no respect.


And yet you felt the need to reply.

Don't confuse need with desire, Skippy. Your bit chomping to reply is kind of entertaining though.

Silly boy.
Chuck Akers
D-10855
Houston, TX

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If I were you I'd be more concerned about running your hero rocket into the ground than I would be about telling everyone else about the dangers of staying alive with an RSL.



Hay thanks Chuck, I'll remenber that the next time I jump it :ph34r:


I'll link to your reply in the incident forum. Hope you don't suffer long.;)


That's a pretty cuntish comment.


I'd tell you what I think of your comment but I don't issue opinion to people too chickensh*t to identify themselves.

No name, no respect.


I don't really care about your opinion of me, but I wanted you to know my opinion of your comment. Mission accomplished.

Clearly you feel better now. Glad you got the chance to stick your nose in.
Chuck Akers
D-10855
Houston, TX

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I have found it better to get stable (belly to Earth), then pull the reserve and allow it to have the best chance of a good opening. All three of my cutaways were on a sub-100 canopy with line twists spinning on my back. My last cutaway was at 1800 feet, main deployment at 2500ft, and open under a perfect reserve by just taking that extra 5 seconds to get stable after spinning three rotations after my cut away.



Here's the flaw in your observations - you openly admit that all of your cutaways were of the same nature, on rigs configured the same way, and with you following the same course of action. The only thing you know for sure is that 'your' method does result in a clean, open reserve after 5 seconds of freefall.

While it's good for you that it worked out, you cannot say from first hand experience that cutting away from the same malfunction with an RSL would result in a less succesful (or unsuccessful) reserve deployment. Truth is, there's a fair chance that cutting away in that situation with an RSL might result in a clean, open reserve without taking the extra five seconds to get stable.

There are many, many cases of jumpers going in with reserves out of the bag, but not fully infalted. All those jumpers need was another 100 feet or so, and the outcome of the jump would have been much different. For you to suggest that just an extra 5 seconds to get stable is no big deal is highly irresponsible, and not something you should be promoting to an audience that certainly includes students and very low time jumpers.

Beyond that, I think it was Bill Booth who posted a good explaination of why an RSL provides for a stable, entaglement-free deployment even if the jumper is not in a stable, belly to the wind configuration. If has something to do the fact that the jumper is attached to the canopy at the shoulders, and the spin of the malfunciton itself throws the jumpers lower body away from the canopy and to the outside of the spin. Upon release of the canopy, the jumper will have an outward trajectory, and as is the nature of aerodynamic decellerators, the canopy will open in the opposite direction of travel. So your feet are toward the outside of the spin, and your canopy is opening toward the inside. Sounds good to me.

As an AFF I, be very careful what you say and always remember that simply prefacing things with, 'For some guys, this is OK....', doesn't mean that people will know to exclude themselves from being 'some guys'. Jumpers in this sport, especailly newer ones, have a way of over-estimating their abilities and tend to make choices based on the jumper they think they are, not the jumper they actually are.

It's the old monkey-see, monkey-do routine. There are a lot of monkeys out there, and if you give them any hint of an idea, they'll run with it, even if you never meant it for them.

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just did some off the cuff math, and figuring you had a vertical speed of 30 mph and chopped at 1800 ft, then after a 5 sec delay your reserve deployed about 1100 feet, with a vertical speed of 90-100 mph. according to tso it can take the greater of 3 sec or 300 ft to deploy, and 3 sec at 90 mph is nearly 400 ft ... so you had your reserve out at 700 ft and still had to unstow your brakes and find a place to land.

Or you could have used your rsl and had your reserve out by 1500 ft with *maybe* a line twist or two ... eg, with twice as much altitude and potentially an extremely minor inconvenience



just sayin'
Brian

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just did some off the cuff math, and figuring you had a vertical speed of 30 mph and chopped at 1800 ft, then after a 5 sec delay your reserve deployed about 1100 feet, with a vertical speed of 90-100 mph. according to tso it can take the greater of 3 sec or 300 ft to deploy, and 3 sec at 90 mph is nearly 400 ft ... so you had your reserve out at 700 ft and still had to unstow your brakes and find a place to land.

Or you could have used your rsl and had your reserve out by 1500 ft with *maybe* a line twist or two ... eg, with twice as much altitude and potentially an extremely minor inconvenience



just sayin'



Where does an AAD fire again? :ph34r:










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

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why an RSL provides for a stable, entaglement-free deployment even if the jumper is not in a stable, belly to the wind configuration. [...] Upon release of the canopy, the jumper will have an outward trajectory,



I'm open to hear more examples, but I can't believe that whole explanation.

Take time to think through the physics Dave and see if you still think Booth's idea makes sense. At all.


1) Physics has an object flung out sideways being spun around. It is not "outward" as in straight away from the center of the spin. Yes, it is "outward" in that as something is thrown at a tangent to the curved path it was on, it will also be moving away from the center of the spin over time. And it feels "outward" in that one isn't being pulled by the spinning canopy.

But to think of it entirely as "outward" is wrong.

So the wind is NOT directly foot to head. The wind will still be coming from where ever it was during the spin. Maybe you are face to the wind, or maybe back to the wind in the classic 'spinning on your back' configuration. (At high G, in a sitting position in your harness = massively dearched, therefore, back to wind)

You chop back to wind, and with an RSL your pilot chute will be jumping out and blowing right back at you.


2) People forget that while rotation around the center of the spin stops when one chops, any existing rotation around one's own center of mass will continue (until changed by aerodynamics)! Some keep thinking falsely, "Yeah but you chopped, you're not spinning any more". Wrong!

So lets say you are facing the direction of spin, and you are in some simplified circular spin with no loss of altitude, going around once per 2 seconds. Then your body is pitching 180 degrees per second. But of course the spiral is actually going downwards fast, so it isn't a pure pitching motion, but one's body is rolling too, as one twists to remain facing forward during the spiral. A combination of pitching and rolling creates the downward spiral.

So when you chop, your body shoots out to the side of the spiral in a straight line. But the turning of your body around its own center of gravity is unchanged! You are pitching and rolling.

Voila, unstable opening as the RSL activates the reserve. Pilot chute, bridle, and lines all moving past the jumper at an odd angle, as the jumper tumbles. An RSL does get the deployment happening fairly fast, so in many cases the instability is hardly noticed.

It is still an unstable opening. That may be OK. Risers don't tend to fail from unstable openings when not at a high terminal velocity. And reserve line twists, while disconcerting, are typically not a problem. But it is still an unstable opening. Uneven risers aren't the best for reliable openings.

Some spinning mals aren't that fast, and the jumper also maintains a face to wind body position. That will help an RSL activate the reserve without the jumper being too unstable in his body position.

I'm not saying RSL's don't usually get the job done, nor that they don't save people who wasted too much time trying for perfect stability. But I think the physics doesn't show the big stability advantage for them as sometimes claimed.

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just did some off the cuff math, and figuring you had a vertical speed of 30 mph and chopped at 1800 ft, then after a 5 sec delay your reserve deployed about 1100 feet, with a vertical speed of 90-100 mph. according to tso it can take the greater of 3 sec or 300 ft to deploy, and 3 sec at 90 mph is nearly 400 ft ... so you had your reserve out at 700 ft and still had to unstow your brakes and find a place to land.


Or you could have used your rsl and had your reserve out by 1500 ft with *maybe* a line twist or two ... eg, with twice as much altitude and potentially an extremely minor inconvenience



just sayin'



Where does an AAD fire again? :ph34r:


Well Sir, I was under a PERFICTLY good reserve at 1200 feet and not kicking out of a line twist and I'm pretty sure my Cypress would have fired at 1000 if I had done nothing because I remember the feeling of how cool it was being back in free fall that low and accelerating. If you want, you can see a video of my 1st cutaway and were I pulled the reserve a couple of seconds before I should have but it still came out okay but it would have been a real mess if I had an RSL. http://www.youtube.com/watch?v=xLebpl4PRQc
Faster, Faster, Faster
Till the Thrill of Speed
Overcomes the Fear of Death

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Any instability after a cutaway is caused by the jumper kicking and wiggling. So stop kicking and wiggling.

Regardless of what spin you might be in, the very instant you cutaway, any body is thrown in a straight line. Enjoy the straight line and let the reserve pilot chute do its thing.

You are willing to allow you reserve to be fired using an AAD if you are unconscious and possibly tumbling/spinning right?

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just did some off the cuff math, and figuring you had a vertical speed of 30 mph and chopped at 1800 ft, then after a 5 sec delay your reserve deployed about 1100 feet, with a vertical speed of 90-100 mph. according to tso it can take the greater of 3 sec or 300 ft to deploy, and 3 sec at 90 mph is nearly 400 ft ... so you had your reserve out at 700 ft and still had to unstow your brakes and find a place to land.


Or you could have used your rsl and had your reserve out by 1500 ft with *maybe* a line twist or two ... eg, with twice as much altitude and potentially an extremely minor inconvenience



just sayin'



Where does an AAD fire again? :ph34r:


Well Sir, I was under a PERFICTLY good reserve at 1200 feet and not kicking out of a line twist and I'm pretty sure my Cypress would have fired at 1000 if I had done nothing because I remember the feeling of how cool it was being back in free fall that low and accelerating. If you want, you can see a video of my 1st cutaway and were I pulled the reserve a couple of seconds before I should have but it still came out okay but it would have been a real mess if I had an RSL. http://www.youtube.com/watch?v=xLebpl4PRQc


Hummm...what am I not seeing, the canopy you chopped did not appear to be in too radical of a spin, from the video it looks like you wouldn't really have had a big snag problem with the camera if you DID have an RSL...

I don't see where you would have had a lot of line twist to BE concerned with on that one.

Your chop to reserve was 3.5 seconds...well within reason by MY comfort zone given the altitude.

BTW...I don't use an RSL either....just sayin', I don't understand your comment.










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

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I've recently switched to having an RSL after 5 years without - and I jump a highly loaded Velocity, with cameras too. I realized that a lot of the "conventional wisdom" against RSL's was simply wrong, and that low-pull no-pull fatalities are simply more common, and more dangerous than the ones involving RSL's.

_Am
__

You put the fun in "funnel" - craichead.

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If you want, you can see a video of my 1st cutaway and were I pulled the reserve a couple of seconds before I should have but it still came out okay but it would have been a real mess if I had an RSL.

http://www.youtube.com/watch?v=xLebpl4PRQc


Every fight is a food fight if you're a cannibal

Goodness is something to be chosen. When a man cannot choose, he ceases to be a man. - Anthony Burgess

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