I'm planning a trip to Perrine in July and I could use a little help from anyone with personal experience jumping this object slider-up.
I have used a slider before, but never on an object this low. I would appreciate any tips on how to induce a speedy opening, or at least prevent a snivel.
Thanks in advance
Steve Redinbo
My first question is specifically why you are interested in making a slider up jump at Perrine. What other elements in your jump evaluation are pointing you towards slider up? All other things being equal, a slider up deployment will take longer, put you in the saddle at a lower altitude, and increase the probability of an off heading opening. Why do you want to do that?
Perhaps you are planning to exceed 3 seconds of delay, or add a safety margin for aerial maneuvers, or have an injury requiring a softer opening. I don't think using a slider makes the Perrine jump unsafe, but it does change some of your options - especially in the areas of delay, clearing line overs, and set up time for landing.
If you decide that a slider is required to meet the parameters of your jump, take a little time to see what adjustments may be required in the three areas mentioned above.
My slider up experience at Perrine includes everything from nice crisp openings to a water landing caused by a very slow slider. Equipment age and line type can dramatically affect your results. Asking 50 different BASE jumpers for tips will probably get you 200 opinions, but here are the things that have worked for me.
1) no micro-reefing
2) do not stow the slider with a rubber band
3) only one wrap for the main stow (some people advise not doing a main stow at all)
4) 42" pilot chute
5) Pro pack (however you do it)
6) do not use sliders on Cruislites with original lines
7) use a mesh slider
8) make first jumps over the water while tesing deployment speeds
9) make your delay at least 2 seconds
Perrine jumps leave minimal time for landing setup (especially when winds require a 180 turn) so be alert after deployment. The landing portion of a slider up jump at Perrine does not last long.
Good luck - be safe.
Surber, Why does using a slider increase the probability of an Off Heading opening ??? B.A.S.E. # 75
angular momentum. the longer the canopy is contained from spreading out, the easier it is for ambient forces to act on the canopy (uneven risers, wind, container contact). i.e. ice skater spinning arms in vs arms out.
>My first question is specifically why
>you are interested in making a slider
>up jump at Perrine. What other
>elements in your jump evaluation are
>pointing you towards slider up? All
>other things being equal, a slider up
>deployment will take longer, put you
>in the saddle at a lower altitude, and
>increase the probability of an off
>heading opening. Why do you want to
>do that?
I'm very aware of the small margin for error associated with using a mesh slider from under 500'. Although I would never consider using a slider on a jump under 600' over hard earth at this point, I think the added safety factors of Perrine(bridge, water to cushion potential impact, fairly obstacle free landing area) provide an excellent platform for experimenting with a low slider-up jump in case I need to call upon the experience sometime in the future. These situations may include multiple-ways or ariels(if I ever find the time to get the proper training and advice). I do not intend to see how close I can get to the water before deploying, I just wish to find the best combination of packing and other techniques to make a jump such as this safely.
A lot of the things you listed were already a part of my plan: pro-pack, no micro-reefing, loose locking stow, no slider stow, 42" PC, and at least a two second delay over the water. The equipment would be a velcro container and a new Fox 245 VTec w/ multi or a Mojo 260 with about 60 jumps, both with their factory mesh sliders.
I appreciate your information and your concern. Just one question: What provoked you to jump Perrine with a slider?
Steve
Over Memorial Day weekend I did many up and down jumps at Perrine, with only a two that were not aerials. After a while, and one rock my world slider down opening I was going up all the time and loving it. With a 2-1/2 to 3 sec delay I was in the saddle below 100'. The ground still rushes up once your stood up and I really felt like I was using all my altitude.
On all of these jumps I made sure I was over the water, but not so far that I couldn't make it back with the low openings. When the slider hit the bumpers the toggles were poped and I rode the surge to shore and landed.
A word of caution. If you don't really know your equipment, how your canopy opens, how to deal with opening surge close to the ground, etc, you should go slider down. A diving off heading opening can pound you into the water, or break you if it dives towards shore. If you are close enough to make shore, you will be close enough to face this situation, if you are far enough to not worry about it, you will get wet on any off heading or slow reaction.
Have fun, but know all the variables,
Tree
actually angular moment of inertia
My one tip:
Never take more than 5 seconds from that object...
It's your call, but slider up from 475??? WHY?
My advice is simple, jump over the water
Joe
OK, that is a fair question. I jumped slider up at Perrine to provide an added safety margin for aerial practice. I completed 8 reverse layouts at the cave in Mexico where I had 1,100 feet to work with. Then I attended Dwain Weston's aerial workshop in Portland. First we learned the theory of aerials, and then practiced the moves over and over and over. The two days spent in training was equivalent to hundreds of BASE jumps.
In working up the courage to put all my training to the test at Perrine, I delayed a slider off jump for 4 seconds, and had my skeleton rearranged. Dwain recommends slider up on a canopy you don't mind getting wet for your first aerials at the bridge. In case you get disoriented, or open late, the slider can help prevent injury. So, I used slider up for my first aerials from the bridge. Just so you'll know, I determined the following numbers by reviewing the video. After additional coaching, I completed a single reverse layout in 1.5 seconds from exit to pitch. I had a good canopy over my head about a second later and took about 14 seconds to fly a 180 pattern, reach the shore and land. My first aerial went well, but if it had not, the slider could have been a major help. I will of course defer to Tom who has the most expertise in matters of delay at Perrine. As he says, anything past 5 seconds is not recommended ;-)
Hi Steve -
How's it going? Are you still in Bodybagger territory? If so, tell Bruce I said hi!
I just checked my log book and I have 76 slider-up jumps from the Perrine. Like you, I know that 480ft is not conducive to slider-up jumping, but when approached properly, there are ways to do it with relative safety.
Why did I decide to go slider-up at the Perrine?
Labor Day 1999 was my first trip to the Perrine. I made 7 slider-down jumps on the first day and woke up the next morning feeling like I had been ran over by a train. I too was curious about slider-up deployments in a very sub-terminal environment and after considering all of the variables, I realized that this would be a good place to learn. Out came the mesh slider.
By no means was I the first person to do this, but for myself, I was pioneering. Some of my BASE friends looked at me like I was insane...but I was simply taking a very specific situation, considering all of the variables, and then using that situation to learn something about my gear and my limitations. Not a foolish idea at all in my book.
I've experimented with many different things in my pack jobs (and I still am) and I feel as if I've achieved very rapid openings off the Perrine while using a mesh slider. Fast enough that I've recieved many unsolicited comments on the speed of my openings. Is it anything special? Not really. But I do feel as if I have *some* practical experience in this arena should a particular jump call for this style of jumping.
I've met you before and I know why your looking into doing this -- to also learn more about your gear and your limitations. As a few of my BASE jumping friends would say: Good onya mate!
While by no means definitive, here is how I usually rig for a slider-up at the Perrine:
1. Both direct and in-direct control of the slider. (primary stow and rubber-band stow on the slider) However, on a recent trip to the bridge, I made a few jumps with just a primary stow on the lines and found the openings to be quite rapid. Some people have experimented with no primary stow -- I personally recommend against it. Too many chances for a premature deployment of the slider which could lead to tension knots, asymetrical deployment of the slider and many other nasty things.
2. I still microreef (CR method)
3. I make a definitive air channel between the left and right groups of lines, split the slider between the A/B and C/D groups, and fold it neatly on top of itself for the front and back portions.
4. Nose inlets are straight with the center cell wrapped around the entire pack job.
5. When the "ears" are placed into the pack-tray, I fold them very neatly and to the side so the bridle will not touch them when the container comes open and begins to pull the canopy off the pack-tray. (It's my theory that sloppy packing for that last fold may cause the bridle-attachment point to catch on an ear and induce an off-heading as the canopy comes off your back)
6. As with any jump, shoulder position is important....but in my opinion, even more so with sub-terminal slider-up deployments. Try to look at it this way....with the slower opening on a reefed canopy, any deviation between your shoulders (riser attachment point) could be potentially amplified during the slower opening sequence. For this reason I like to pay particular attention to *really* centering my shoulders for deployment.
7. 42" PC
8. In my experiences, a 3 second delay puts me open below 100 feet. And with that delay, a 90 left places you awfully close to splashing down. As Tree mentioned, use extra caution to avoid surging if you open really low and then release your brakes and immediately transition to full-flight...it can get you in trouble pretty fast!
As your doing...always evaluate each and every variable and try to avoid more than one new variable on any one given jump!
C-ya,
Bryan Stokes
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