):
February 21st, 2002 Okay, does anyone think it is possible to do a 200' b with a static line? How would you go about doing this, attach somthing like an 80lbs break cord to your briddle? Bad deal is if we were to do that we would be leaving evidence that we were there...but no one would have any clue as to what that static line is....Is it possible? Is it bad mojo to leave evidence?
Any opinions would be welcome :9:o
February 21st, 2002 Definatey, provided you have a sufficient landing area and the weather is good. I made a Sl off a 220' B last night, this particular object has been jumped ALOT, so there are at least 20 or so SL at the exit point (never use left over ones from before as they are exposed to UV and weather and therefore could break prematurely) I don't think it matters on this object that there are alot of SL's left, but your's may be different, never assume they won't know what a SL is. Bottom Line, this is probably not a beginner jump so I would say find an experienced jumper and take them to evaluate the site. Actually, some folks routinely freefall objects of this height (not me:7 ), have fun and be safe!
February 21st, 2002 Hey Blair,
one thing to do when your putting a new cord to static line to... cut off any ones left at the exit by you or others. Clean up the site and it will be jumpable for a long time. Or until they complete construction:D Also, there are a lot more things to consider than weather and landing area!
Oh by the way... nice tree landing at (that top secret 300footer!);-) It was funny video!!
Peace
570
February 21st, 2002 Did a SL off a 200' b last year. I just brought a non-jumping friend to watch, take video & clean up the site. But I know that this is not allways possible.
February 21st, 2002 Tom's advice looks great. I thought I should add a couple of things.
I have in the past tied the break cord directly to the object without use of a static line, where it would have been difficult to recover my gear afterward. The problem is that this setup could result in a premature break because of the rough surface the break cord is in contact with. I've used a sock wrapped around the rail to soften the corners, but have since come up with a better idea. I picked up some white half-inch tubular webbing of the type used for abolakovs in ice climbing. It's 1100 lb breaking strength, milspec, and cheap like dirt. I cut about two feet of this and tie it around a convenient rail at the exit point, using a tape knot (see http://www.compusmart.ab.ca/resqdyn/...nots/Knots.htm). I tie the break cord directly between this sling and the bridle. When I jump, all I'm leaving behind is a little white loop of webbing which I can cut off next time I'm there.
Also I wanted to comment on the pilot chute. On any object where there's a possibility the pilot chute will help (for me this is anything over about 140 feet), I leave it attached. We've been doing a lot of jumps from a local 111-foot S, and finally I decided to remove the pilot chute. My thinking was this: On this particular object, the pilot chute probably won't do me any good in the case of a premature break. I'm very much depending on the static line to work properly, and by removing the pilot chute I feel as though I'm being a little more honest about myself on this point. Also, the pilot chute adds one more part to the system, and a bit of drag. By removing the pilot chute for jumps from this object, I think we may improve consistency.
I know that for objects like our little S, we could improve opening altitude by using either a skillful PCA or a d-bag rather than a static line.
I'd be interested to hear other people's comments on the decision to remove the pilot chute.
Michael
February 21st, 2002 It is possible to rig a static line so that the left over cord after breakage remains tied to your bridle and thus jumps down with you. I'm not going to try to explain how to rig this. First, if you can't figure it out yourself then you don't have enough comfort with the mechanics of the system to do it safely while introducing this extra element of complexity versus a 'standard' rig.
Second, I've not done it myself and I won't recommend something that I have not done.
You will need a bit more more break cord than usual to do this setup, and this will add some marginal weight to your bridle/PC combination such that it could have a tiny effect on your canopy extraction in the event the static line breaks early and you end up relying on your PC for shrivel flap removal and canopy extraction. I can't imagine it would be enough weight to make a statistically meaningful difference in freefall opening speed, but I've not run the math to back that up.
A properly rigged static line from a 200 foot object should, in my experience (less than 10 in total) result in canopy pressurization with ample time for landing setup given a good, close landing area and reasonable winds at the object. However, if something goes wrong from this height (or the object is 'dodgy' in some other way), bad things will happen FAST with little time to react. I broke my ankle static lining from 150 feet last year when two minor things went wrong on the jump; I was fortunate to get away with only that injury. These are serious jumps, though sometimes we don't think so much about that and they can become pretty routine.
I would second advice above and strongly suggest you approach this object only with an experienced jumper along to provide guidance. If done right, it will be fun and instructive and (reasonably) safe. If done wrong, it could result in a quick and messy death.
Peace,
D-d0g
ddog@wrinko.com
www.wrinko.com
February 21st, 2002 Can you elaborate on the 150-foot jump you broke your anke on? I'd like to hear a little more about the object itself, but mainly I'd like very much to hear about the two things that went wrong. Thanks!
Michael
February 21st, 2002 >Definatey, provided you have a sufficient
>landing area and the weather is good.OOPS, AMONG OTHER THINGS!!!!!! See your BASE instructor!
February 21st, 2002 No problem. Always happy to share my foibles!
1. About a 40 degree off heading opening to the right. We were jumping into a mild headwind, so that might have contributed. Or maybe my body position was a hair off. Or maybe my pack job was asymmetrical. Anyway, a moderate off-heading which was nonetheless a surprise when being PCA'd. Yes, one can get off-heading openings with a static line or PCA. Less common, but the CAN happen.
2. Missed the right toggle first try as the off-heading accelerated into a 100-130 degree because of the headwind which turned the canopy further. Actually, I got the toggle with a finger but not completely and I made the judgment call to go straight to rear risers given the height of the object. Now I jump Big Grabs and have never had this problem since. Call me a believer.
Thus I landed rear risers, essentially downwind. And I landed under this B where there is very little light (not even much AMBIENT LIGHT, ha ha - Pacific NW joke). I misjudged the rear riser landing and I think flared a bit too early. In any case, I knew I hit the ground only when I hit the ground. Somehow my right leg got under me in a funny way and the ankle rolled sideways. Fortunately, I had one of Mick's old (fabric) ankle braces on and it minimized the trauma. Unfortunately, I still tweaked the ankle enough to cause five separate avulsion fractures (two on one side, three on another).
Finally, I was jumping an unvented canopy with approximately 1:1 exit weight wingloading. That takes away any margin for error I really had given the above two errors/mishaps. I hit the ground hard and fast and downwind and blind.
The object is a B with a good (grass) landing area, and lasers somewhere between 150 and 155 feet from the common exit point, depending on the roll of the landing area below exit. It has seen multiple freefall jumps, just to provide a baseline of comparison, so a static line/PCA from it does have a margin for error built into it, ceteris paribus. It gets jumped alot.
What I learned from this (apart from how much 1:1 wingloading really sucks for a new BASE jumper), is that there is a certain amount of margin in low jumps (freefall or PCA/static line). Each deviation from an optimal exit/throw/extraction/line stretch/pressurization/on-heading/steering/flare eats up that margin. The lower the jump and dodgier the situation, the less margin. The less margin, the fewer incremental mishaps are needed to cause a serious incident.
From there, it's simply up to one's own calculations of the probabilistic distribution of the jump and all its variables, as well as one's willingness to incur statistically significant risk. For example, had I been freefalling that jump instead of PCA and the same mishaps had occurred, I'd have almost certainly been much, much more seriously injured or killed. There's less margin to start with, and I used all the margin up even with the PCA.
Remember that, statistically speaking, mishaps are linearly additive at best. At worst, mishaps accelerate and amplify one another and two mishaps on the same jump might add up to a really bad scene whereas each mishap individually - happening on separate jumps - might not be really awful. It is the jumps where two (or three or four or. . . ) things go not quite right that keep me up late at night.
Generally, I feel that I am mentally ready for one mishap on any given jump and I am reasonably confident that I can respond fairly well to common problem scenarios (off-heading, line-over, blown brake line, turbulence, line twists, bad body position, bad exit, etc.) one at a time. However, add them up and things happen fast and in confusing and scary combinations. Like that jump last week with the bad exit, head-down deployment, crosswind, 110 degree off-heading opening, and scary buttress right where it shouldn't have been. That $hit is nooooo fun. Tail between legs. Fortunate to walk away with only a bruised ego.
Sorry to ramble; hope it was marginally (ha ha) helpful.
Peace,
D-d0g
ddog@wrinko.com
www.wrinko.com
February 21st, 2002 Our weekly fix is a 170 foot S/L when we have nothing better to do.
90lbs breaking strength cable tie works well and generally comes down with you. Give it a pull first to make sure it's locked and always put your 46 or 48 inch PC on.
Email me for more details Skinflicka@hotmail.com
February 21st, 2002 Didn't I just read a whole other thread about this by our friend Huckin Idiot? Who needs a s/l? Just drape the canopy over the edge and jump past it!!!
I really liked Tom's explanation but I thought the reason for static lining was you're alone. If you have friends at the exit point isn't a PCA or even a d-bag a better way to go?
Just wonderin'.
Skypuppy:+
February 21st, 2002 >I really liked Tom's explanation but I thought
>the reason for static lining was you're alone.
>If you have friends at the exit point isn't a
>PCA or even a d-bag a better way to go?
If the friend you have at the exit point is a non-jumper, or a jumper who has no d-bag or PCA experience, you might be better off using a static line.
Given a wider choice, I always opt for a direct bag if time, experience and available helpers permit.
--Tom Aiello
tbaiello@ucdavis.edu
February 21st, 2002 Thanks for the clarification.
I guess I'm out-dated but the first time I did a d-bag neither I nor the holder had done it before - I just read Mark Hewitt's article 'Romancing the Rope" in Baseline and thought it didn't sound too hard - being a rigger I just stuck a couple of quick links through a d-bag, added 2 toggles as handles and a static line to tie it off to the object just in case and packed it up. I did stress holding the bag right way up, but I was still a bit nervous. It opened up fine.
Always wondered why more people seem to use PCA than d-bag.
Skypuppy:+
February 21st, 2002 If you are a new jumper, it is very unwise to even think of going to a 'B' at 200'. Actually, you should get a decent base instructor to get you to 100 BASE jumps or so then you can start thinking of such a jump.
But hey, that's me!
500+ base-jumps, no injuries, 75+ different objects, 10 countries.......
What do I know....
February 21st, 2002 Well you could look at it as being object dependent. There have been 1st timers put off a certain local 210 ft B. Depending on the corner you may be only able to hit a grassy field...
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