base736

Hey guys, this is a great project. If you're an editor, sit down and hammer something out for a section that's not yet written. It'll take you a half an hour. If you're not an editor, take a peak and see if there's anything you could write about. Then become an editor. You don't have to be an expert -- just a regular jumper.

Freefall or S/L? A couple of the locals here static lined a 111' span over hard ground a few years ago. Repeatedly. Total time from exit to landing sat somewhere near 3 seconds, and the canopy was almost flying when they hit the ground. You know it's low when the second guy (hardcore by anybody's standards) says to the first, "I'm just going to watch to see how yours goes before I make my decision; I've got a trip to Malaysia coming up and can't afford to break my legs." And you know the first guy is hardcore when he jumps after the "break my legs" discussion. More generally, asking about lowest jumps opens a can of worms that can only lead to lots of video of similarly low jumps (because certainly they've been done) and stories about rocket-deployed mains and (as above) freefalls done from couches, roofs, etc.

"My armour saved me" stories always make some assumptions about things that, in point of fact, didn't happen (ie, what "would have happened" if one hadn't been wearing the armour). That always sets off alarms somewhere in the back of my head. That said, I would argue that my armour saved my ass (or back, as the case may be) in this incident. As it turns out, I compression fractured my back anyway -- somebody has already pointed out that back protectors don't do much for that. But I hit going backward (and down) fast, and I'm pretty confident that the outcome would have been different without the back protection.

I've been jumping with the Dainese Shuttle Pro suit for a couple of years now and love it. It's super-comfortable (ie, I can wear it all day) and it's saved my ass more than once when I probably shouldn't have walked away. That said, I've seen the Velocity Gear stuff and, externally at least, it's so close in design to the Dainese (ie, all of the holes and ribs are the same) that I'm stunned they haven't been sued, then sued again just for good measure. Anyway, the VG stuff is a bunch cheaper -- you might want to check it out, too.

Wow. That's totally a... What did you say I should call it? A nugget? Right -- that's totally a nugget. ... Like that, right? Seriously, though, well put. Very well put.

These sorts of statistical things always bug me. I think maybe (and, then again, maybe not) the reason for that is illustrated by a recent experience... A couple of weekends ago, I was standing at the top of the tall bridge in Colorado (sure, I could name it, by why start now?) in conditions that I would characterize as "questionable". Some people were jumping. More were chosing not to. If you aren't already familiar with it, the thing you need to understand about this bridge is that it sits 1000 feet over a tight gorge. With a landing area the size of a hanky. Whitewater on one side, bluffs, cliffs, and ankle breakers on the other. All of that said, the successful jumps by other jumpers (if I assume that my skills are on par with theirs -- so I'll flatter myself for a moment) seem to indicate that my odds of actually injuring myself that day (I didn't jump all day) were less than 5%. For all the talk some jumpers make about "my odds are 50/50 on every jump", I respectfully suggest that those individuals have no idea what 50/50 odds would feel like. 5%, as it turns out, is enough for me to seriously consider turning back. What's my point? I don't leave the object unless I feel my odds of injury on this one are less than something like 5% -- probably much less (because, you see, I'm soft like that). Perhaps your goals would therefore be better served by a list of "things to watch out for when BASE jumping". No percentages. The fatality list would be a good place to start. In the name of being particularly helpful, though, here's a bit of a contribution... Sometimes this stuff can hurt you. And sometimes it's just part of a great day you BS about in the bar afterward. --- Things to watch out for when BASE jumping: - Body position at exit. And on opening. And in between. - Stuff in your packjob that makes you think, "Should I reapack this?" - Strange winds at exit. Any kind of instability, even in low winds. - Strange winds in the landing area, or during the climb to the exit. - Gnarly rocks in the landing area. Or on your intended flight path. Or near it. - Trees, especially big ones, along your intended flight path, even if you'll "definitely clear them". - That feeling that you're not quite with it, just now, at the exit point. - Aging gear. Is this pilot chute still good? Does my velcro need replacing? - New stuff. Aerials. Wing suits. New object. New rig. - Stuff you forgot. Left your helmet at home? Not sure this rig is slider-down? - Wierd stuff that happened to the guy who just jumped. Particularly on opening or under canopy. - Ice. - Black elastics. - Bystanders, animals, and expensive stuff in the landing area that you might bury a toggle to avoid. - Fog, darkness, and other conditions that make it hard to see. - A last minute change of plans. For any reason. Of any kind. Go ahead. Expand on this list.

Which definitely has its place. Just to reinforce the other side of the picture (because it is my firm belief that the way things were once done is not always representative of the way they should be done), we had a jumper locally who was driven strongly by a desire to learn things on his own. It's my opinion (the person involved knows that I respect him) that that played strongly in his subsequently having a close encounter of the Building kind. BASE can be pretty unforgiving with respect to "learning it on your own". There's a significant difference between teaching yourself when to use pointers, and teaching yourself when to use a 42.

At the risk of threadjacking... I was treated, Friday, to the second crappy CG BASE scene I've witnessed on television. Is this economics? Or are producers (?) just generally not big on getting stunts like a BASE jump (no flying Corvette or anything) done the old-fashioned way? The CG stuff is so mind-numbingly bad that I find it hard to believe that even non-jumpers aren't immediately turned off by it, whereas an actual BASE jump would be, well, pretty exciting for everybody.

See ya there! Crwper and I will be heading down. I've been preparing to piss myself -- from what I understand, it's mandatory.

Glad to hear you're (mostly) okay. Not a lot you can do about those large ledges and pillars in that situation. Seems ya did good.

I had the same vertigo standing at the exit point (a 3-foot high wall, eight inches deep, on a corner) of the first building I came close to jumping. The conditions were perfect. It was our intended exit point. I told my buddies I couldn't do this, got a hand back down (what is it they say in climbing -- 80% of accidents happen on descent?) and descended the staircase while they jumped. Chicken 'B' for me. Everybody walks down from stuff that's perfect at some point. Walking down from something that's 40 feet lower than your plan 'A' (and therefore not perfect) was probably a wise choice. If it's good, you can always go back for it, right?

What's to disagree with? With respect to (4), I certianly haven't trained a bellymount into my procedures, and I suspect the same is true of most other jumpers. With respect to (2), most of the jumps I do around here are a 3-second delay with impact at ~5 seconds, and I suspect 1-2 seconds is too little to deploy a bellymount. With respect to (3), my recollection of Nick's list is that object strike does, in fact, dominate, and that other situations in which a reserve would not have helped (low pull / no pull, for instance) make up the bulk of the remainder. Edit to add: Of course, a partial mal would be slower and would give more time. Most partials are already treated by, for instance, the line release mod and WLO toggles.

The way I've heard it said, and say it myself, is like "Sher-AHG". It could just be that the Norwegians I've talked to are very tolerant.

As long as I get to go hand-held. I've set a personal hard deck of 350,000 feet for stowed jumps.

So, something a little over 2,000 mph at re-entry. For comparison, the SR-71's top speed sits around mach 3.2, or 2,400 mph at 85,000 feet. My understanding is that it got pretty warm. In my professional opinion, this is both safe and an excellent idea. I'll, umm, be right behind you, DexterBase. Edit to add: Yeah, skin temperature of 427 Celsius at Mach 3.3. But hey, if you can't stand the heat...

I love vents (and owe the good people at Apex a beer) for that very reason. I'll go one better, though this is mostly conjecture on my part. Perhaps somebody could support or correct this. Another important factor in avoiding and, failing that, surviving a 180 on a solid object is the tuning of your deep-brake settings. Time is good, and speed at impact is bad. My realization, this weekend, was that vents/valves allow a little more leeway in tuning the deep brake settings. The transition to the dreaded deployment stall is, I think, less severe on vented canopies, so that one can more easily (and repeatably) achieve low to no forward speed on opening. My very humble suggestion is that anybody who is not jumping exclusively spans and terminal walls invest in a vented and valved canopy. The above should be taken with the following grains of salt, in particular: (1) I have only a few jumps on an unvented canopy, and it wasn't mine, and the DBS wasn't tuned; and (2) on the only 180 I've had, circumstance and a response which was less than optimal resulted in my using the vents to walk (uninjured) away from, but notably not avoid, an object strike.

Well, there's your problem. Four seconds slider down? The novelty of even three seconds wore off for me by the time I had thirty jumps! But then, I'm all soft and stuff.

Talked to Miles about this a couple of months ago when he was up this way. I'm really excited to see how it goes. Good luck, and play safe! Edit to add: Hehe... Look at that... There's a whole thread already dedicated to this. My bad.

I roll the three cells on either side of the center cell tightly maybe a half-dozen times (so that I've rolled them back to the centerline of the packjob). The center cell I pull tight down the center, rather than pulling it around the packjob as I do for slider-down. I'm not sure how much of a role that plays in slowing the openings. As I indicated above, I've definitely noted a correlation between the number of wraps I take on direct control (I take three these days -- feel scary the first time, but really isn't) and the softness of the opening. I would probably go so far as to say that direct control is the single most important factor. I think it goes without saying that hard openings are almost always better than none at all. I did a few jumps in Norway (without injuring myself) without rolling the nose or effectively using direct control before I started using both to slow things down, so if you're unsure, I'd recommend you err on the side of a brisk opening.

I've done a number of slider-up jumps, no slidergate. As I recall, the frequency of lineovers on a carefully-packed canopy goes down dramatically when the slider is up. Which isn't to say that the slidergate isn't a good idea, but it's probably not sport death to jump without. I've never folded my stabilizers 45 degrees, slider up or down, and I've never been quite sure why people do it at all. Again, I wouldn't worry about it (clearly, I don't). When I'm switching to slider up, I make sure of a few things: 1. Slider up (of course) 2. Shallow brakes 3. Lines through the guide rings 4. Lines through the slider grommets I believe that's all there is to that. I'm a big fan of using both direct and indirect control on the slider. Direct control, in particular, seems to slow the openings considerably (which isn't to say that they don't snap open respectably anyway).

Go for your eyes. Cover 'em up; I find imminent object strike is a lot less frightening if you can't see it coming.

I call it "not a functional canopy". Of course, there are dozens of things that can happen to a parachute on deployment that will cause a turn after an otherwise on-heading opening -- blown toggle, lineover, tension knot, fabric or line failure, daisy chaining... To call any of these an "off heading" would be counterproductive, I think.

Is there? There are, I think, only three causes for off-headings on a functional canopy. Perhaps somebody can correct me if I've missed something... (1) Packing error; (2) Body position at deployment; (3) Wind at deployment altitude. (that last can come in either directly, or perhaps indirectly through the PC). In every off-heading, each of the three comes into play to some extent or another; one could cite jumps in which any one of the three was clearly the dominant factor. Why each comes into play might seem obvious in advance or simply fall under "black death", depending on who's doing the looking. Luck is not on the list. Edit: Although part of this quote has now disappeared from the original post, I think the rest bears saying...

Not true. Look up Persi Diaconis, who's managed a simple machine that flips heads 100% of the time. Without being particularly mundane about the flip. Word has it he can do the same manually. Even very complex dynamical variables can often be controlled. Not saying it always works, but there's a lot more to it than (as one article posted here once said) jumping and "hoping" that the parachute opens.

Yeah, that's in line with my experience. I find that having a cliff or bluff to one side (either from exit or due to a rotation in freefall) tends to give an off-heading toward the cliff. Some kind of magnetism, maybe?