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BASE104
Social climber
An Oil Field
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Jun 30, 2016 - 12:24pm PT
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Some people will not let others determine the path that they take in life. Friends, families, even children.
That is not for me to judge.
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BASE104
Social climber
An Oil Field
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Jun 30, 2016 - 12:31pm PT
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AK, you didn't see the video of Ammon's foot broken so badly that it was looking at him? He opened 180 off and hit the cliff. Moab has a ton of exits on BLM land, totally legal. They are 500 feet or so, so you take 2 second delays, and if it isn't overhung, a wall strike can happen. We used to have 180's fairly often in the early days. Modern gear and pack jobs make it much less frequent, but you have to be ready for it on every jump where it could be an issue.
That wouldn't have happened on El Cap. On El Cap any idiot can, even with a moderate track, be 200 feet from the wall when you open.
I never saw an injury in person. I've never had one happen around me during all those years of climbing, jumping, even at the DZ, where I've seen tens of thousands of jumps. Even that summer when I was in SAR, I only went out on one search. Nothing bad happened in the valley that whole time.
I'm like a lucky charm. Take me along and nothing bad will happen. Except to me. I've broken my right foot and ankle 3 times. Once on a BASE jump at night and twice bouldering.
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 12:42pm PT
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the Fet wrote:
... statistics play a part of my decision making process.
It's tough with BASE because it's so unregulated that highly reliable statistics are not available, but you can still get a pretty good idea. For BASE it's roughly estimated to be 1 death per 500-1000 jumps. And yes different disciplines are inherently more risky. Statistically compare that to skydiving 1 death per 100,000 jumps. I think about it over a lifetime of doing it. I'd see myself doing 1,000 BASE jumps or about 5,000-10,000 skydives. That means there could probably be a 1 in 1, pretty good chance I'd get killed BASE jumping vs. a 1 in a thousand chance I'd get killed skydiving. BIG difference. I agree that statistics can be useful, and your analysis is roughly correct.
However, doing 1000 trials with a probability of 1/1000 failure does not equal a 100% chance of failure. The math does not work that way.
(Fundamentally, we know there is a nonzero chance of surviving all 1000).
Instead, the chance of failing at least once in 1000 trials is actually equal to "One minus the chance of surviving all 1000 trials".
So the equation is Pr(at least one fail) = [1 - (1-p)^n] (if all trials are independent).
Applying this to the p and n values you gave:
.63 = Pr(BASE death for 1000 jumps with p = 1/1000 in each)
.86 = Pr(BASE death for 1000 jumps with p = 1/500 in each)
.049 = Pr(skydiving death for 5000 jumps with p = 1/100000 in each)
.095 = Pr(skydiving death for 10000 jumps with p = 1/100000 in each)
So your rough assessment was correct, assuming these values for p are good.
(The rough assessment is Pr = n*p, which is the leading term in the full equation, and is pretty close for n large and p small).
And extending these calculations to climbing:
.049 = Pr(climbing death for 1000 days with p = 1/20000 in each)
.095 = Pr(climbing death for 1000 days with p = 1/10000 in each)
[Yes, these line up with skydiving]
.15 = Pr(climbing death for 3333 days with p = 1/20000 in each)
.28 = Pr(climbing death for 3333 days with p = 1/10000 in each)
Note:
1000 days = 20 years x 50 weekends x 2 days/weekend x 1/2 of weekends climbing
3333 days = 50 years x 50 weekends x 2 days/weekend x 2/3 of weekends climbing
These values of n are probably on the high side for most climbers.
While I know these equations, if I was to use them for my personal risk assessment, I'm not sure what value of p to use.
Am I safer than the average climber?
Or have I just been luckier so far?
Am I doing riskier climbs, or less risky climbs?
In general this is called "subjective probability" estimation.
It's hard to do with limited observations on low probability events,
so we lean on the overall statistics more, if they are any good.
For the overall statistics, there is always a problem estimating the denominator of the fraction:
p = (Number of deaths)/(Number of times people did the activity at risk)
We have good counts of the numerator (Number of deaths), but the number of times is usually not as accurately measured.
Still, I don't give up and say everything is equal risk.
Use the stats we have, and try to adjust them a little for what we think is wrong with them.
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the Fet
climber
Tu-Tok-A-Nu-La
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Jun 30, 2016 - 12:48pm PT
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Moose, I think we can compare objective dangers to some degree. It would be very difficult statistically because we simply don't have the data. But those are often factored into the overall risk statistics. And a reasoned analysis of the objective dangers in BASE often have more deadly consequences than trad climbing, since the most common outcome is a trad fall which can often result in injury but not death. I would say the objective dangers of BASE are more in line with free soloing than trad climbing.
I think BASE suffers from the Pit Bull syndrome where the media likes the sensationalism about a certain activity so you hear about it more, but personally to me BASE IS about as risky as it looks. And it makes perfect sense that proximity flying is MUCH more risky than a regular jump, gut feelings, statistics and reasoned analysis all agree. Just like BASE jumping is riskier than trad climbing. If someone has any experience with trad climbing and BASE jumping and they can't see that difference then they are not a good candidate for BASE jumping IMO because they are not being honest with themselves about the risk.
I have a superficial understanding of BASE from sky diving and my friends' experience with it. I have friends that have had off heading openings on BASE with cliff strikes. I don't have to be an expert to have a general idea of the risk involved and how it compares to other activities.
An anology is that riding a motorcyle on the street is riskier than driving a car on the street. Or that sport climbing has the less risk as trad climbing.
Again, choices are everyone's to make, but when I read that peolple think you can't have an opinion on something unless you are very experienced with it, or saying BASE and trad climbing carry the same risk I'm just not going to agree with that.
What's really interesting to me is pushing the envelope. That seems to be where we are seeing a lot of these wingsuit accidents.
Personally I would rather fly a wingsuit on a skydive. The sensation of flying with a risk about two orders of magnitude smaller. But I understand the appeal of close proximity and the feeling of speed, adrenaline, and accomplishment you would get from that. But to me it's just not worth the risk.
Everything has risk. But you can't lump all risk together like they are the same. Everyone can make the choice of risk vs. reward. I think a lot of what we are hearing is people saying THEY don't agree with the risk vs. reward choices other people are making.
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Todd Eastman
climber
Bellingham, WA
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Jun 30, 2016 - 12:55pm PT
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In any activity, a question could be asked about how the community gives acknowledgement, recognition, and praise; and if the feedback loop influences the risk assessment of (by) the risk taker.
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the Fet
climber
Tu-Tok-A-Nu-La
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Jun 30, 2016 - 12:57pm PT
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Thanks Clint. I get lazy with math and it's been a LONG time since I've done any statistics. I appreciate there are guys like you, that are smarter than me, keeping me honest.
Those numbers I put in for climbing are for Yosemite only. The risk is higher than other sources of statistics I've seen for rock climbing in general. Which is interesting in itself. If valid, what makes Yosemite climbing more risky than other places? More trad vs. sport? Longer climbs? More loose rock? More people pushing their limits past where they should (something I've personally witnessed in Yosemite many times because people get a type of summit fever for a climb they've been dreaming of). I don't expect any answers, but they are interesting questions.
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micronut
Trad climber
Fresno/Clovis, ca
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Jun 30, 2016 - 12:59pm PT
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Snakefoot I appreciate your thoughtful posts on this subject. Thanks for your insights into this activity so many of us climbers are enamored by while often having no framework to comprehend.
Scott
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the Fet
climber
Tu-Tok-A-Nu-La
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Jun 30, 2016 - 02:38pm PT
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Moose, I like a good debate too, I didn't take any offense to anything you wrote, as a matter of fact I can't think of anything you've ever written that was offensive, you are a great contributor to this forum.
As far as trad climbing, I'll will often stop and plug in piece (I just did this a few days ago) when running it out on even really easy terrain. I could run it out with VERY low risk of falling, but the consequence of a fall is so bad that I'll place a piece when I'm in danger of decking. That's a decision I make, but if someone wants to run it out or free solo I understand that. I also don't free solo since I've had kids.
One of the biggest aha moments I had when learning to trad climb was when I asked my mentor, how often do I place gear? Thinking the answer would be X number of feet. But he said, it depends. Think about what would happen if you were to fall at every spot. At the base of a route or over a ledge you want to place often to keep from decking, if you are on a steep wall with nothing to hit you may run it out because it would be a clean fall. Analyzing the consequences and how to avoid them for an error or objective danger is a huge part of reducing risk.
Part of proximity flying is also to open up new exits and lines of descent. Not to get a close as possible, but to do a new line and stay as far away as possible. The problem with that IMO is it relies far too much on unknown factors. I'd want a little radio controlled wingsuit jumper to send off first and test before I committed my life.
I did a search on radio control wingsuit and found this. Obviously it's just for looks, not to mimic a wingsuit flight. But it would be fun to send it off stuff just to freak people out.
[Click to View YouTube Video]
Like this guy did
[Click to View YouTube Video]
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Bullwinkle
Boulder climber
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Jun 30, 2016 - 02:44pm PT
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You have no clue about what you're talking about, yet crap just flows from your mouth. . .
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the Fet
climber
Tu-Tok-A-Nu-La
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Jun 30, 2016 - 02:51pm PT
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And then there's those that have nothing to contribute.
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 04:53pm PT
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I looked for the source of the 1 in 500-1000 jumps fatality rate for BASE.
I didn't find it yet.
The largest survey was 20,850 jumps from the Kjerang Massif in Norway, 1995-2005; 9 fatalities.
p = .0004 = 1/2317.
... and 82 nonfatal accidents (0.4% of all jumps; 1 in every 254 jumps);
Most nonfatal accidents were related to ankle sprains/fracture, minor head concussion, or a bruised knee.
...
CONCLUSION: BASE jumping appears to hold a five- to eightfold increased risk of injury or death compared with that of skydiving. This was mostly before wingsuits became popular (~2003), so it is not a wingsuit fatality rate.
http://www.ncbi.nlm.nih.gov/pubmed/17495709
Similarly, at the New River Gorge Bridge Day, 1980-2012, there were about 1000 jumps per year and 3 fatalities (1983 drowning, 1987 main chute failed; too late for reserve, 2006 too-late deploy).
So p = .00009 = 3/(33*1000).
There is no cliff strike or proximity flight type risk at this location, so it's a bit different.
Bridge Day 2012 Stats
1036 jumps made in 6 hours.
12+ jumpers made five jumps each. 68+ jumpers made four jumps each.
400 jumpers showed up out of 450+ registered
10% female
Roughly 10 countries/territories and 41 US states represented (Australia, Canada, Mexico, Mongolia, Netherlands, New Zealand, Norway, Puerto Rico, USA, Virgin Islands). 3 jumpers from WV.
Oldest jumper was 83 (Donald Cripps from Florida)
Approximately 17% of all jumpers were making their first BASE jump at Bridge Day. Was 24% at Bridge Day 2011.
Nine tandem jumps
Decent weather (58F) and excellent winds all day long with minimal train holds.
Three injuries requiring transport: Two injured wrists and one ankle. All were discharged shortly after the event and most were at the Saturday night party.
Did you know ... 71% of all Bridge Day landings are safely made on shore while 28% land in the water? The remaining 1% is reserved for unfortunate jumpers who opted for the railroad tracks, trees, etc. http://web.archive.org/web/20131022064628/http://bridgeday.info/?
I did find the 1 in 100,000 fatality rate for skydiving (secondary source):
US 2006 21 fatalities / 2,122,749 jumps = 1/101,083 jumps
Sweden 1994-2003 9 / 1,126,704 = 1 / 125,189 http://www.medicine.ox.ac.uk/bandolier/booth/Risk/sports.html
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the Fet
climber
Tu-Tok-A-Nu-La
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Jun 30, 2016 - 05:43pm PT
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Clint my source for BASE risk was this: http://www.wingsuitfly.com/risk/4572000812
It also breaks down the cause of the fatalities, e.g. cliff strike, line twist, etc.
I can't vouch for it's accuracy. I've seen different numbers from different sources, and the unregulated / underground aspects of many BASE jumps impacts the amount of usable data. But as I've said statistics are just one of the tools I would use to judge an activity and I take them with a grain of salt.
The Norway jump location is very similar to El Cap in size so I'd guess it would be similar to El Cap in terms of statistical risk. And the numbers do seem to show they are less risky than BASE jumps in general. I'd guess El Cap would show more statistical risk because it's illegal, so people jump at dawn/dusk, may rush, and try to get to specific landing zones to avoid rangers.
Not all BASE jumpers really understand the risk. Some of the people I knew who were doing it in the 90s had very little idea of the actual risk involved. They were just going for it. We simply didn't have the information available like today with the Internet. At the time I knew that I was hearing about a lot of accidents anecdotally and that was enough to give me pause.
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 06:01pm PT
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Thanks for the link.
Unfortunately it's a secondary source, and they don't say where the "roughly estimated 1 death per 500-1000 jumps" comes from.
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donini
Trad climber
Ouray, Colorado
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Jun 30, 2016 - 06:35pm PT
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Consider this...in climbing everything happens slowly (sometimes excruciatingly so) and adjustments, even retreat, are relatively easy to do. In close proximity base everything happens very quickly and adjustments and retreat are an entirely different matter.
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 06:40pm PT
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I found an article which said there were at least 9000 jumps from Lauterbrunnen in 2007, using a system where jumpers voluntarily call the local helicopter outfit (to avoid a jumper x helicopter collision).
However people often jump in groups for 2+ for better filming, so the 9,000 calls could represent 10,000 - 20,000+ jumps.
http://www.dailymail.co.uk/home/moslive/article-1103214/Staring-death-face-The-truth-BASE-jumping.html
The BASE fatality list shows 3 fatalities for Lauterbrunnen in 2007.
So p might be in the range
p = .00015 = 3/20000
p = .00033 = 3/9000
These values are apparently a bit less than Kjerag 1995-2005 (p = .0004).
However, equipment had improved by 2007,
and the Kjerag fatality rate was apparently decreasing over time.
Usually visit about 300 base jumpers Lysebotn each summer. They perform Average 2500 jumps, plus minus 500. The first years were the statistics daunting. One of around 800 jumps went wrong. Now it's done about 7,500 jumps without fatal since Australian Darcy Zoitsas died on 19 July 2005. He waited too long to drop the screen. http://www.aftenbladet.no/nyheter/lokalt/2700-vellykkede-hopp-fra-Kjerag-2420986.html (2008 article)
See my post on the next page of this thread:
p = .00008 for 2003-2015 at Kjerag.
This puts Lauterbrunnen (2007) higher, unless number of jumps is around 40,000, which is possible.
The 3 Lauterbrunnen fatalities in 2007:
1. Bert Brooks - did not track very far out from the cliff face, had an off-heading opening, then cliff strike. This was a frequent problem before wingsuits; maybe still is, as people may adjust their risk and try more difficult launch points.
2. Oleg Kudria - pilot chute malfunction or maybe not optimal technique (delay before throwing it fully).
3. Alexander Bogoroditskiy - pilot chute malfunction.
Jim is right. In climbing you control the pace, while in jumping you have to react quickly to a problem (and there is no backup).
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 06:56pm PT
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I've also seen 1 in 60 jumps http://www.besthealthdegrees.com/health-risks/ linking to this article: http://archive.is/WIiR9 (just the abstract)
A much different metric than per number of jumps, and the infographic secondary source also fails to mention it is a participant basis.
The article is an analysis using the BASE fatality list (106 fatalities from 1981-2006).
I don't see in the abstract what their method was for estimating the number of participants. (The denominator, which is important and difficult to estimate accurately).
I found a cited 2004 article in Norwegian which presents an estimate of 700 global active participants and 35 in Norway, in 2002.
They did not state how they came up with the 700 figure.
http://docplayer.no/5881546-Basehopping-nasjonale-selvbilder-sublime-opplevelser.html
Given 12 fatalities listed for 2002 in the BASE fatality list, this yields a 1 in 58 participants figure.
Note: 4 fatalities in 2001 and 8 in 2003, so 2002 might not have been a 'typical' year.
Here are 2 other articles with smallish N based on surveys of surviving BASE jumpers.
1. Clin J Sport Med. 2012 May
The epidemiology of severe and catastrophic injuries in BASE jumping.
Mei-Dan O, Carmont MR, Monasterio E.
SETTING: BASE jumping group meetings from 2006 to 2010.
PARTICIPANTS: Heterogenic group of 102 International BASE jumpers.
RESULTS: Responses from 68 subjects were available for analysis. The median number of jumps was estimated at 286 per respondent. The median time respondents had participated in BASE jumping was 5.8 years. There were 39 reported severe injuries sustained by 29 different jumpers. Nineteen thousand four hundred ninety-seven jumps were reported, resulting in 2 severe injuries per 1000 jumps (0.2% severe injury rate) or 2.6 severe injuries per 1000 jumping days. Forty-nine respondents (72%) had witnessed the death or serious injury of other participants in the sport. Twenty-four accidents (61%) involved the lower limbs, 8 (20%) the back/spine, 7 (18%) the chest wall, and 5 (13%) were a head injury. The mean Abbreviated Injury Score was 3.2 (range, 2-5). Fifteen (52%) of the 29 injured jumpers required 20 acute surgical interventions, which were mostly orthopedic related. There was a significant correlation between number of jumps made and injuries sustained (P < 0.05).
CONCLUSIONS:
BASE jumpers have an average of 1 severe injury for every 500 jumps. Most active BASE jumpers have witnessed death or severe injury of a participant and have experienced a "close call" incident.
Maybe this is where the 1 in 500 figure came from??
If so, it's wrong, as this is a rate of injuries, not fatalities.
The N in this study is fairly small (N=68), and it is of surviving jumpers, so it doesn't shed much light on fatality rates.
http://www.ncbi.nlm.nih.gov/pubmed/22450590
2. N Z Med J. 2008 Jul 4;121(1277):70-5.
Risk and severity of injury in a population of BASE jumpers.
Monasterio E, Mei-Dan O
METHODS:
To determine the frequency and characteristics of BASE jumping accidents, a cross-sectional survey of experienced BASE jumpers was completed.
RESULTS:
35 BASE jumpers enrolled in the study. Findings revealed that there were approximately 9914 jumps made and the estimated rate of injury was 0.4%. 39 accidents involving 21 (60%) BASE jumpers were found. 28 accidents (72%) predominantly involved the lower limbs, 12 (31%) involved the back/spine, 7 (18%) the upper limbs, and 1 (3%) was a head injury.
CONCLUSION:
BASE jumping is associated with a high risk of serious injury and appears to be significantly more dangerous than skydiving. Earlier and smaller survey by the same authors. Mei-Dan is a BASE jumper.
http://www.ncbi.nlm.nih.gov/pubmed/18677332
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 07:10pm PT
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So, we are back to statistics.
Which is very simplistic. Maybe so, but it's the only accurate way to estimate the probabilities that enter risk calculations.
The main difficulty is finding surveys with largish N that measure something close to the activity of interest.
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donini
Trad climber
Ouray, Colorado
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Jun 30, 2016 - 07:15pm PT
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Not entirely....statistics can be simplistic to a fault. If you look at the stats for fatalities in climbing are you to assume that extreme alpinism and sport climbing are equivalent regarding risk?
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Clint Cummins
Trad climber
SF Bay area, CA
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Jun 30, 2016 - 07:25pm PT
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Moose wrote:
Certain sports attract certain personalities. That's why I would really like to understand the objective dangers of those activities.
Statistics (if surveyed on the right population) will usually tell you roughly the average probability of an outcome (death, injury, etc.), across all participants.
Sometimes it can stratify by different groups in the study.
For example, male vs. female and bridge vs. cliff.
It can't tell you what the probability of death is for a particular personality type is, unless that has been classified as part of the study.
By objective danger, do you mean different ways to die?
Or do you mean something quantitative, like probability of each way to die?
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