Jump numbers and canopy accident risk

[DocPop 1]

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....incorrect use of the word 'risk'. You don't seem to understand what it means.


So, why did you give up on the Katana? Could it have something to do with 'risk'?

Risk is defined as "exposure to the chance of injury or loss" (dictionary.com app for iphone). The guy with 4,000 jumps has been exposed 4 times vs 1 time for the other guy.

I changed back to the Sabre2 because I was getting so much shit for the Katana here. I am bored on the Sabre2, but since everyone else here seems to think it is the right thing, I can't ignore that. So yes, risk. Other people's (very experienced people, granted) perceived risk based soley on my jump numbers.

My only close call came on the Sabre2 (low turn) and I have not had anything like that on the Katana in 50 jumps. I may change back to the Katana next year in a another 100 jumps or so. I'll see how long I can be bored/frustrated with the Sabre2 for. I now only land the Sabre2 downwind.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[wmw999 2,560]

I took a look at the fatality reports for a fairly decent period (I haven't updated in a couple of years; I need to), and counted the number of times that different possible risk factors were mentioned. In the case of low-turn landings, sometimes it's impossible to determine, but I still counted if they were landing off, or aiming at obstacles -- both of those would seriously decrease the likelihood that the party was deliberately swooping (unless the commentary indicated otherwise).

Of 190 landings where a low turn was involved (out of 800+ fatalities), 22 were off, 11 involved obstacles, and 15 had both indicated in the report. This count does NOT include any sort of accounting for newbies who were definitely trying to get into the wind but on the DZ, etc -- i.e. people who clearly were not swooping.

This is all just me, reading fatality reports; someday I'll get it up to date and maybe even do something with it.

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)

[Southern_Man 0]

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Always ready to give info when available, here is an extract (in attachment) of a document where you can identify my sources. The whole document was available at the PIA symposium at Reno Nevada in 2007. A seminar was dedicated to this facet of skydiving.
Are you by any chance a marathon runner ?

Yes, I am a dedicated runner, anyway. I've only done one marathon but numerous half-marathons and other shorter races.

I poked through those links (thanks for providing them) but couldn't go through the whole website and was not able to find a source for the marathon runner claim.

Some quick google searches revealed statistics reported ranges elsewhere of 1 death in 50,000 to 1 death in 220,00 for marathon participants and an overall participant death rate of 1 per 800,000 hours spent in running or jogging.

"What if there were no hypothetical questions?"

[DocPop 1]

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Of 190 landings where a low turn was involved (out of 800+ fatalities), 22 were off, 11 involved obstacles, and 15 had both indicated in the report.

Do you have a breakdown of the jump numbers of those involved in these 190 landings?

That would be some pretty interesting raw data.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[wmw999 2,560]

Remember that if you're trying to prove a point, you're going about using data wrong. You try to disprove it -- if you fail to do so, then it's probably a valid point.

It's harder to get that the way I have it tabulated, but I'll take a look.

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)

[DocPop 1]

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Remember that if you're trying to prove a point, you're going about using data wrong. You try to disprove it -- if you fail to do so, then it's probably a valid point.

It's harder to get that the way I have it tabulated, but I'll take a look.

Wendy P.

Thank you, Wendy.

I started this poll to gauge people's opinion - the results so far are quite interesting. Not the landslide of votes for option 1 that I had expected. This thread might provide some useful basis for a canopy BSR if one were ever seriously considered.

With your data I saw an opportunity to get some harder "facts". I am not emotionally tied to any one outcome as long as it is well supported by data. I have been proved wrong before and no doubt will be again.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[erdnarob 1]

Thank you Wendy for sharing other statistics. All together we should hopefully get near the reality.

Learn from others mistakes, you will never live long enough to make them all.

[grimmie 186]

Remember that for every fatality under canopy, there are probably 20-30 serious injuries under canopy. So to do a "canopy collision, swoop injury, landing injury" type of survey, you would need a lot of info to make it an accurate picture. Remember that only a handful of injuries world wide make it here in the DZ.com forums. And it should be an international study, since we all jump together everywhere in the world. Which should then lead to establishment of international BSR's and training.

[wmw999 2,560]

What I've come up with.

Notes: This is a little over 800 data points; all the fatalities I could locate between 1/1996 and 10/2008 (I quit tabulating then and haven't kept it up -- but plan to some day). Obviously the coverage in the 90's isn't as good as the 2000's, but it is what it is. I read the descriptions, and, without taking into account if it was a swoop or not (because there was often disagreement, or it was impossible to tell), I marked if a low turn was involved in the fatality's cause.

The low turn could have resulted in an unsurvivable impact with ground or obstacle -- I didn't differentiate. I have additional identification if the landing was said to be off, or obstacles -- but that isn't always listed. Age and number of jumps aren't always listed either.

There's a wealth of data in here, and I'm not good enough with statistics to do much with it. That said, I attached a picture showing what I came up with for low turn fatalities. This does not do anything with trends etc. I'd really appreciate it if someone with more statistical knowledge than I have could play with this; I'll update it, and my classification methodology is listed. Folks might not agree with it , but it's pretty consistent.

Actually, the most interesting piece of data to me is that demos seem to be very disproportionately represented: some sort of demo was mentioned in over 5% of the fatalities, and no way demos are even close to 5% of total jumps.

Note: The data don't seem to support the assertion that lower-jump pilots are getting hurt disproportionately. OTOH, we don't have numbers on all jumpers, or non-fatal incidents. And data is to be shared, even if it doesn't support one's conclusion

Note 2: That applies to you folks who want to run out and buy little baby canopies and think this justifies your decision, too

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)

[DocPop 1]

Thanks for posting this Wendy.

It is very high level, but at least we have SOME data here.

I hope someone takes you up on the offer of doing some more statistical analysis.

Base on this initial information, the USPA might want to look at changing the jump # scoring for their canopy risk quotient quiz (or just taking that scoring point out altogether).

I guess the only solid conclusion we can make at this stage is that everyone is at risk.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[wmw999 2,560]

The standard deviation makes it clear that there are some serious outliers -- one of the first things to do would be to find a statistically valid way to pull out the outliers. The medians are much lower than the averages (indicating to me at least that the high-jump-number fatalities have an undue influence on the average).

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)

[DocPop 1]

Not trying to make you do a load of work on this (!!!), but could you post the medians?

Thanks.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[faulknerwn 38]

The age I find interesting as well. From what I've seen around me, young jumpers start docile and start working their way to more aggressive canopies. Somewhere around age 35-40, most start, um, feeling their age, and start mellowing out both in canopy flight and canopy choice..
I suspect that the canopy choice of the average 45 year old is considerably more conservative than canopy choice of the average 30-35 year old...

The way I see it is that someone with 100 jumps jumping a 1-1 loaded Spectre is more at risk than someone with a thousand jumps on a 1.5 loaded Spectre. I think that someone with two thousand jumps on a Velocity 88 is more at risk than that 100 jump jumper on the Spectre.
Canopy Choice is a huge factor.

[davelepka 4]

Just to back up what grimmie said, any of these fatality reports are just that, fatalities. None of these take into account the number of non-fatal incidents under open canopies, and in turn, the level of injury within those incidents. A rash of twisted ankles is one thing, and a rash of compound fractures or incidents resulting in paralysis is another.

They also don't reflect the jumpers who are injured as a result of others while under an open canopy. There have been a good number of collisions where one jumper was killed, and the other was injured, but the data will only reflect the fatality. Again, since the jumper was not killed, the data will not appear on a fatality report, but the incident and injuries were the result of poor canopy piloting, and would need to be considered along with the fatalities.

[DocPop 1]

I take your point, but are reliable non-fatal incident data available?

If not, we just have to work with what we can get.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[davelepka 4]

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I take your point, but are reliable non-fatal incident data available?

If not, we just have to work with what we can get.

No, that data is not available.

In looking at 'what we can get', we have to assume that the presence of non-fatal injury data would paint a much, much darker picture. As bad as the fatality data may make things appear, the truth of the matter is far worse.

Consider briefly the number of fatalities you have witnessed, and then the number of non-fatal incidents. For the purpose of this discussion, let's call a non-fatal incident an 'incident' if the jumper requires a hospital visit as a result, everything else is just a 'hard landing'. Personally, my ratio is at least 10 non-fatal incidents for every 1 fatal incident. I would be surprised if other jumpers didn't have a similar ratio.

With further regards to 'working with what we have', even that is not detailed enough to really pinpoint the problem. it would take a detailed report of every incident, to include the jumpers overall jumps, canopy progression and training, size and type of canopy involved, and a myriad of other details that would allow the reader to determine the root casue.

In the absence of such data, we can clearly see that open parachutes are the area of concern. The obvious stpes would be to increase the training and awareness about canopies and canopy piloting. In addition (here it comes) some restrictions on the size and type of canopies jumpers can access with regards to jump numbers has proven to 'do no harm' in other countries, and most likely has done some good.

Jump numbers are not a guarantee of anything, but like most areas of risk management, we need play the averages. If an average jumper seems to be able to handle a WL of 1.2 at around 200 jumps, then that's the number. Some will be ready sooner, and some will not be ready by 250 jumps, but you need to 'run' things such that the majority of jumpers will reap the benefits. The number of jumpers who will avoid or reduce the severity if injury will far outweigh those naturally talented jumpers who will be 'held back' jumping a canopy beneath their skill level.

Even if there are more naturally talented people being held back in comparison to the number of jumpers who avoid injury, I would propose that if we hold back 5 jumpers for every 1 who avoids injury, the sport is still ahead in the 'big picture'. If one person can avoid injury, that's worth having 5 guys feeling 'oppressed' (which is an interesting word for a jumper in the US with the financial wherewithall to persue sport skydiving, there are worse positions to be in out in the world).


We're talking about people being made PIC of an aircraft with very little training. A jumper who does reasonably well with a student canopy will not hear much about canopy flight beyond the FJC with the exception of an 'atta boy'. Meanwhile, we have privately run canopy control courses where if you took the beginner, intermediate, and expert courses concurrently, it would run a solid week of 10 hour days discussing nothing but canopy flight. With this much information at hand, all we require is one section of the FJC, and some precursory 'tips' offered in order to satisfy an A license proficiency card. Beyond that, everything is optional, and by virtue of being optional not bestowed with much value in the eyes of newer jumpers.

I'm not suggesting the FJC have the canopy control portion expanded, there are more immediate issues at hand, like teaching EPs, and with the conservative student gear in use and watchful eye of an AFF I making sure things go well, the first jump student doesn't need to know anymore. What about when they go from a 280 to a 260? How about to a 240? Or when they're cleared to self-supervise? Or given a license?

We whittle away the layers of protection put in place on AFF level one, but never turn up the flow of information to match. Nobody should be surprised that 75% of the fatalities thus far in 2010 happened under open canopies.

[DocPop 1]

Well put, Dave.

I graduated AFF feeling extremely unprepared for the canopy part of the skydive (I never jumped anything larger than a 200).

I believe that there should be some more mandatory canopy control tuition for the B and maybe even C licenses.

We continue to require jumpers to perform freefall skills for license progression when, as you rightly point out, the real danger is from canopy accidents (both landings and collisions). There needs to be more than just accurate landings as an assessment of canopy skill for licenses beyond the A.

The UK has Canopy Handling (1&2) and Canopy Piloting (1&2) syllabuses which would make a great starting point for this.

Perhaps young pilots who wish to advance/downsize faster than the recommendations could be allowed to do so if they pass these 'advanced' courses. In other words, you want to do it, you have to earn it with skills, not just by not dying a certain number of times.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[nigel99 586]

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What I've come up with.

Note: The data don't seem to support the assertion that lower-jump pilots are getting hurt disproportionately. OTOH, we don't have numbers on all jumpers, or non-fatal incidents. And data is to be shared, even if it doesn't support one's conclusion

Wendy P.

A few months ago I tallied the fatalities from 2004 to 2009 broken down by jump numbers (it was just a quick capture from dz.com reports into excel). The way I captured the data doesn't allow for more detail than what is provided in the graph but with 107 fatalities for jumpers with 250 jumps or less and 38 for 250-500 jumps it is quite dramatic. Obviously there are millions of people with 1 jump and alot less with 500. The spike at 5000 is because I simply did 5000+

Experienced jumper - someone who has made mistakes more often than I have and lived.

[Floflo 0]

Those are the FAI numbers for 2006:

www.ffp.asso.fr/IMG/pdf/CTN_Annexe6.pdf

I couldn't find the latest reports.

[riggerpaul 1]

I think it is really interesting that there is a blip centered on each 1000 milestone. No, not a very big blip, but a noticeable one nonetheless.

[PhreeZone 20]

I know the cause for that. Often times people will say "Jumper had more then 2000 jumps" or something similar so I will put 2000 into the database for that incident. Its not that the incident occurred on their 2000th jump but with out an accurate number I'd rather go with an estimate.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[wmw999 2,560]

that's probably partly because a lot of people estimate jumps, and in building a fatality report, people base the jump numbers on what they know, which tends to be even numbers. Only if the jumper is a good logger, and their logbook is found, is the number likely to be accurate to the jump.

After all - according to dropzone.com, you have 1500 jumps. How many do you really have?

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)

[riggerpaul 1]

Of course. Doh!

[DocPop 1]

I assume these are total fatalities, rather than canopy/landing related incidents? Can you confirm?

Thanks.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[wmw999 2,560]

Here they are. Again, we don't know how they compare to the medians of the jumping population at large. USPA might have that information from its membership database, but that's also not necessarily reflective, as there are non-active jumpers who join USPA.

median age lowt        33	

median jumps lowt      500

median age all         35	

median jumps all       350

median age non-lowt    36

median jumps non-lowt  300

I put together another chart showing the groupings by age groups (picked rather randomly) and jump experience (again picked somewhat randomly).

I'm going to have to break down and go enter the rest of the fatalities now, aren't I

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)