New USPA Downsizing Chart proposal

[justinb138 0]

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>If people are going to be expected to follow the chart, the requirements at least need to be reasonable.

The possibility exists that your downsizing progression, rather than the chart, is the unreasonable progression. "I didn't die" is not proof of a reasonable progression.

It's possible, but ending up @ 1.1 on a 230 after 100 jumps isn't "Black Death" as the chart describes either.

[nathaniel 0]

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The possibility exists that your downsizing progression, rather than the chart, is the unreasonable progression. "I didn't die" is not proof of a reasonable progression.

Likewise, "somebody got injured or died" is neither proof that it's unreasonable. It seems like there's no easy way to plot a line between certain death and certain success a priori for the choices that people are making today.

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[faulknerwn 36]

I've heard a couple of people mention being over the limits on their student jumps. What are some of the "progressive" dzs - like Skydive Chicago - using for student canopies and how would they fit on their chart?

Most places around here are still using more traditional/larger canopies, but I know that Skydive Chicago always had a unique program... If their numbers are higher than typical - how would their students/graduates fit in?

W

[davelepka 4]

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a first step to understanding the nature of canopy flight would be to identify isolines of a particular level of performance. Say canopy speed on a well trimmed canopy of a particular make, with various weights and with no control input, with 25% input, 50% input, etc. at known density altitudes.

This is where more information about your experience or expertise would help to support your point.

The reason being that canopy speed has nothing to do with this. Every canopy is capable of achieving speeds that would result in a fatal impact. This has been proven by several deaths do to low turns on very lightly loaded student canopies.

The WL issue comes into play because the lower your WL, the bigger mistake you have to make to result in an injury.

Your determination of canopy speed will not help the issue at all. This is what I'm talking about when I sufgeest that you're missing the point. You're trying to make rocket science out of something thats really quite simple.

If it seems to work so well in so many European countries, why wouldn't it work here? Most countries in europe have devised their own charts (which are all striking similar), and they seem to be doing the trick.

Your use of big words and advanced concepts makes it so hard for me to understand why you can't see the simplicity of this situation.

[billvon 2,406]

>It seems like there's no easy way to plot a line between certain
>death and certain success a priori for the choices that people are
>making today.

There is no way, period. I know first jump students who likely could have landed a Stiletto 107 without serious injury. Likewise, if you fly your Manta into a powerline, it can easily kill you. The best you can do is make the best possible tradeoff between slowing down the superstars and protecting the less-competent. No two people will decide where that line is the same way. So the issue is not to get a perfect line (there is no such thing) but a line that works well _enough._

Now, I've only got 4700 jumps, and I have put >20 jumps on fewer than 20 canopies - so I don't consider myself an expert on canopy flight. In addition, while I have taught a lot of AFF (~1100 AFFs or so) most of the training I do under canopy is for people flying Mantas, Sabre 230's and Triathalon 190's - so I don't consider myself an expert on high performance canopy training. But I do think Brian is one of the top five canopy instructors in the country, and thus I place a lot of weight on his opinion.

[MakeItHappen 15]

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The reason being that canopy speed has nothing to do with this. Every canopy is capable of achieving speeds that would result in a fatal impact. This has been proven by several deaths do to low turns on very lightly loaded student canopies.

You are contradicting yourself.
Speed is the driving factor.
The ROT is:
Impact at low speeds = survival
Impact at high speeds = death

ROT = rule of thumb

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The WL issue comes into play because the lower your WL, the bigger mistake you have to make to result in an injury.

Your determination of canopy speed will not help the issue at all. This is what I'm talking about when I sufgeest that you're missing the point. You're trying to make rocket science out of something thats really quite simple.

Nathaniel was citing something I posted.

WL is proportional to speed squared.

The figure shows three canopies that have such-n-such speed at such-n-such WL. (steady state)

If you draw a vertical line at some speed, then you can say that those three canopies at those three WLs have equivalent performance (at least to the first order by matching steady state descent rates).

The question is, why can't I say canopy 1 = Acme Student, canopy 2 = Acme New Guy and canopy 3 = Acme Super Swooper?

The reason I cannot do that is because I do not know the lift and drag coefficients of each of those canopies.

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Make It Happen
Parachute History
DiveMaker

[billvon 2,406]

>Speed is the driving factor.

Yes. But that's like saying you can measure how safe a car is by driving it (with your feet off both brakes and gas) and measuring its speed. The REAL issues are how good its brakes are, whether it tends to oversteer, whether it's good on ice, how fast it can go at wide open throttle etc.

Similarly, you could find a size of Velocity that flies at the same speed as a Pilot 132. That would NOT mean that they are equally safe. The issue is that if you screw up, the Velocity will drive you at the ground much faster than the Pilot will.

[davelepka 4]

No. The point is that you cannot look at speed of any kind as an indicator of the canopies safety for lower experienced pilots.

Steady state speed, maximum speed, speed in a turn, none of that info is relevant becasue, lie I said, ANY canopy can go fast enough to kill you.

Determining speed in not going to reveal that canoyp x cannot exceed 8 mph, and cannot kill you.

The issue is WL, and lower WLs mean you have to make a bigger mistake to get hut.

You can turn a Manta, loaded at .7 to 1, a full 180 from 50ft, and have a good landing. You cannot make that same manuver on a 220 Nav.


ONCE AGAIN: This is not rocket science. The scope oif available canopies, their performce potential, and the nature of novice jumpers makes it neccesarry to have a system of some kind in place.

I'LL REPEAT: Most european countries have had a WL chart in place and enforced for many years with great success. It does work, It can work. Lets make it happen.

A side note: The truth is that if you have a problem with the chart due ot your personal situation, your opinion does not count. Your experience is such that you cannot make a truely informed decision, and either A) you will progress beyond the chart rather quickly, or B) you will quit jumping soon, and we don't care what you have to say.

The people who this chart is intended for, and whom will reap the biggest rewards have not even made a jump yet. Many of them have not even been born.

Learn to look beyond yourself. For every nit pick that you have, there are 1000's of future jumpers preparred to accept whatever climate they ancounter when they start jumping. These are the people who need it the most.

Rest assured that even if a chart was adopted by the USPA today, it would be at least a year before we figure out how to realisticly enforce it. If you're not jumping enough to not be affected by the chart at the end of next year, you are the sort of person who needs it the most.

Again, the catch 22 is that those who really need it, don't knwo it, and are against it.

[MakeItHappen 15]

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>Speed is the driving factor.

Yes. But that's like saying you can measure how safe a car is by driving it and measuring its speed. The REAL issues are how good its brakes are, whether it tends to oversteer, whether it's good on ice etc.

I can't believe you made this post?!?!?!?!

You are one that is always advocating 'low WL, low WL' because the severity of the accident would be less. You are always advocating changing the severity of a hazard as opposed to advocating changing the probability of occurrence.

Back when the US instituted the 55 mph speed limit during the 70's gas crisis, the NTSB noticed that the number of accidents where about the same, BUT the severity of the accidents was less under the lower speed limits. After the gas crisis disappeared, the speed limit remained low 'in the name of safety'.

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Similarly, you could find a size of Velocity that flies at the same speed as a Pilot 132. That would NOT mean that they are equally safe. The issue is that if you screw up, the Velocity will drive you at the ground much faster than the Pilot will.

You jump to conclusions.

First order of 'performance equivalency' is steady state descent rate.

Then you can add in turn rates etc.

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Make It Happen
Parachute History
DiveMaker

[billvon 2,406]

>You are one that is always advocating 'low WL, low WL' because
>the severity of the accident would be less.

Right. And?

(You're not equating speed and wingloading, are you? You know they vary depending on canopy design and total size.)

[MakeItHappen 15]

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>You are one that is always advocating 'low WL, low WL' because
>the severity of the accident would be less.

Right. And?

(You're not equating speed and wingloading, are you? You know they vary depending on canopy design and total size.)

Are you just trying to be difficult??

Let's see, I just posted a graph that showed the relationship between speed and WL. Do I think they are equivalent? I'll leave it to the reader to decide.

At the same time one can also say a generalized statement of 'Lower WLs result in lower speeds'.
Just draw a horizontal line on that graph at several WLs. You'll see that the speed decreases for a given canopy as the WL decreases.
WL = a v^2 where a is around 0.001111111 to 0.003333333 and
a = f(Cl, Cd, glide angle, density)


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Make It Happen
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DiveMaker

[MakeItHappen 15]

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ONCE AGAIN: This is not rocket science.

I know. It is a freshman physics problem. Some of us even learned this in HS.

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I'LL REPEAT: Most european countries have had a WL chart in place and enforced for many years with great success. It does work, It can work. Lets make it happen.

Why don't you go ask John LeBlanc about how he sees what the Europeans are doing. It may be enlightening.

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Rest assured that even if a chart was adopted by the USPA today, it would be at least a year before we figure out how to realisticly enforce it. If you're not jumping enough to not be affected by the chart at the end of next year, you are the sort of person who needs it the most.

USPA does have guidelines. See page 108 in the 2006 SIM or Online SIM.

I'll even repost the graphic (that represents the USPA data).

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Make It Happen
Parachute History
DiveMaker

[brierebecca 0]

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Brian, can you adjust the 110 exit weight to be more real world realistic and move towards a max min size of 97/105 by 500 jumps and 120 as the midline? I tend to agree that a 120 as max smallest for a little person at 500 jump is a little on the too cautious side.

I'm one of those "little people" and I agree. I haven't always made the right decisions regarding canopies, but being required to load at .7 at 500 jumps (135 square feet), no matter what the size of the canopy, would have really pissed me off at the time. I know smaller canopies perform differently than large canopies, and are more aggressive in general, but the performance difference between a 120 and a 107 is not so much that it would make a huge difference when loaded lightly.

BTW, I'm currently on a XF2 109, and I have about 850 jumps. I'm still only loaded at about 1.2. It's plenty fast for swooping, at least at this stage, but when flown conservatively, I could easily have handled this canopy at 500 jumps.

Maybe there should be a canopy distinction for smaller jumpers as well. There's a HUGE performance difference between a Triathlon or Sabre 120 and a Katana 120. I wouldn't have flown a Katana under 500 jumps, but would be more comfortable with a Sabre or Spectre or Triathlon. I flew a Sabre 1 (107) when I was approaching the 500-jump mark.

Just a small girl's opinion.

Brie

"Ive seen you hump air, hump the floor of the plane, and hump legs. You now have a new nickname: "Black Humper of Death"--yardhippie

[brierebecca 0]

oops! Sorry, didn't see your adjustment.

However, I would argue that a 120 loaded 1:1 and a 170 loaded 1:1.7 would perform much differently, with the 170 being much more aggressive, despite the fact that the 120 is smaller and has faster turns.

Once again, I think it also depends on which canopy we're talking about. See my post above.

Also, please take my posts on this for what they're worth: just a small female perspective. I'm offering my opinion on how I've had smaller canopies perform at light wingloadings, and I don't claim to be any sort of expert.

Brie

edited for spelling

"Ive seen you hump air, hump the floor of the plane, and hump legs. You now have a new nickname: "Black Humper of Death"--yardhippie

[kelpdiver 2]

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The probability of "black death" for jumpers at 1.1 is pretty damn low, Jan. Virtually non existent, even.

The fundamental flaw in new jumpers' thinking is that they assess the risk level improperly, not what risk level they are assuming.

This picture has the current USPA suggested WL limits displayed with the risk zones noted.

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This graphic is not present on the PDF version of the SIM. Just a recommendation of a WL of 1.0 for A/B, 1.2 for C, 1.4 max for D until proven otherwise.

Which of course has no bearing with reality. We already know that jumpers tend to get their rig somewhere in the ballpark of 50 jumps, and they tend to get a main in the 1.0-1.1 range, per vendor recommendations. And "Black Death" ain't happening, showing that the risk analysis is just fine. Moreover, the past two years have shown that death has been chasing the experienced flyers, not the overly aggressive newbies.

The problem seems to be at canopy 2 or 3, when some choose to get into that 1.3-1.5 range ahead of themselves.

[ChasingBlueSky 0]

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I've heard a couple of people mention being over the limits on their student jumps. What are some of the "progressive" dzs - like Skydive Chicago - using for student canopies and how would they fit on their chart?

Most places around here are still using more traditional/larger canopies, but I know that Skydive Chicago always had a unique program... If their numbers are higher than typical - how would their students/graduates fit in?

W

When I started there 6 years ago we had just transitioned from the original Sabre to the Safire as the student canopy. Now they have been using the Sabre 2 for several years and the largest size is 260. Roger and his top instructors (and some local jumpers) gave feedback to PD on the creation of the Sabre 2 for it to work as a Student Canopy when they sent us the prototypes. I'm not an instructor there, nor have I been out there in a year so I can't speak to how the program is currently running (nor would I try).

I heard Roger speak on this topic many times in the years I knew him. The idea of AFP and the canopies we learned on were to encourage positive muscle memory and an easier transition to personal gear. This lead to typical cutaway systems for students and BOC's (remember how much of an outrage that topic made??). As a student of that program, I promise you that the amount of instruction for canopy progression was just as strong as the 20 freefall jumps I had to make. I've gone to the canopy pilot sessions by Germain, LeBlanc, etc over the years and the majority of it was just a refresh of what I learned from all of my AFP instructors (like learning half break turns on jump 6/20 for example).

The amount of respect and education I learned in that program is beyond what I used to see at other DZs. This is why I asked if there will be anything BEYOND a simple spreadsheet that doesn't factor in most dynamic variables related to skydiving. Without good pilot education these new rules will not change a thing. Having things on paper is one thing, having things in practice is another. IMHO, education is the only thing that will change the culture surrounding the "Go fast/small/hook as soon as possible" trend.

_________________________________________
you can burn the land and boil the sea, but you can't take the sky from me....
I WILL fly again.....

[RedassSkychic 0]

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Moreover, the past two years have shown that death has been chasing the experienced flyers, not the overly aggressive newbies.

The problem seems to be at canopy 2 or 3, when some choose to get into that 1.3-1.5 range ahead of themselves.

Maybe if these kind of wingloadings/canopy sizes are enforced and taught early on, the attitude of these jumpers, when they become more experienced, will be different than the current attitude? That could take a long time though. It would be alot easier to change new jumper's attitudes than experienced jumpers; I think anyway. Maybe not

Why do we have two threads on this topic?

[nathaniel 0]

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I'LL REPEAT: Most european countries have had a WL chart in place and enforced for many years with great success. It does work, It can work. Lets make it happen.

Make what happen? I'm not making fun of the Euros, but they have a long and sordid history of overregulating themselves. They nearly destroyed their insurance industry in the late 20th Century with bad laws.
In the USA our culture is to do things differently, to hold off on massive overregulation until someone gets put in charge who wants a legacy. And then to bicker about it endlessly. Short of dedicating a wing to ourselves in the USPA museum, we should focus on effective & appropriate regulations. That means gathering data on subjects we don't know enough about.

My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

[kelpdiver 2]

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Maybe if these kind of wingloadings/canopy sizes are enforced and taught early on, the attitude of these jumpers, when they become more experienced, will be different than the current attitude? That could take a long time though. It would be alot easier to change new jumper's attitudes than experienced jumpers; I think anyway. Maybe not

I think newcomers (in any sport) follow the example of the more experienced they jump with. Set a good example and change goes quickly. But decline to (grandfathering at some extreme level) and it takes two generations - the first to be forced to a new approach, and the second to then see it as the norm.

The other slowing force is the lack of canopies and rental rigs in the proscribed 210/230/+ sizes, including Brian's Lotus. I imagine this is due to the current lack of a market, which would eventually fix itself, but in the transition would be discouraging to some.

[RedassSkychic 0]

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Maybe if these kind of wingloadings/canopy sizes are enforced and taught early on, the attitude of these jumpers, when they become more experienced, will be different than the current attitude? That could take a long time though. It would be alot easier to change new jumper's attitudes than experienced jumpers; I think anyway. Maybe not

It takes two generations - the first to be forced to a new approach, and the second to then see it as the norm.

good point. How would you propose regulating more experienced jumpers? a similar chart that extends to greater jump numbers?

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The other slowing force is the lack of canopies and rental rigs in the proscribed 210/230/+ sizes, including Brian's Lotus. I imagine this is due to the current lack of a market, which would eventually fix itself, but in the transition would be discouraging to some.

Do most dropzones not have those sizes for students?

[kelpdiver 2]

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good point. How would you propose regulating more experienced jumpers? a similar chart that extends to greater jump numbers?

No, I think by some level of experience, be it X jumps or the D license (my preference), people have proved they have sufficient experience to make choices. But the very common acts of asking 'why do you have such a large canopy' or 'go ahead and downsize, you'll be fine if you're careful' sabotage the efforts a lot of the people posting here have been putting forth.

If guidelines or BSRs are put forth that a majority of people see as silly, then they won't respect it or promote it well to the new jumpers.

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Do most dropzones not have those sizes for students?

AFF students, defintely. Students, mostly, but they usually must defer to the AFF students if both want a rig. A holders, I found availabilty to be pretty poor at many DZs in CA above the 210 size. If you wanted a navigator/manta 260/280, you'd probably be ok, though again subject to student needs. But to rent higher quality sport gear you might think of buying...different game entirely and it drove me to buy my gear sooner than I had intended. Also had me making choices that showed me the edge of the envelope.

If every 200lb guy had to or choose to use bigger canopies, then the supply would grow, but if grandfathering was in effect, the rate would be fairly slow until enough new anvils joined the sport.

[Jeth 0]

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I've heard a couple of people mention being over the limits on their student jumps. What are some of the "progressive" dzs - like Skydive Chicago - using for student canopies and how would they fit on their chart?

Most places around here are still using more traditional/larger canopies, but I know that Skydive Chicago always had a unique program... If their numbers are higher than typical - how would their students/graduates fit in?

W

I graduated from SDC's AFP back in May. Back when I started reading the posts here and talking to other students I was surprised to find out how large of canopies they were using. My very first AFP jump was under a Sabre2 190, which put me at about .9:1. Many of my fellow students were downsized to 1:1 before they graduated. I was kept on a 190, and bought one after graduation. But after getting my license I heard from many people that my canopy was too big for me. I just bought a 170, and I feel like it is a good canopy for me. I demo'd a few different ones and I didn't feel like it was too fast for me. I stood up all my landings under them, and hit my target almost every time.

When I was under the 190 around 40-50 jumps, it felt very slow and non-responsive for me. I was always the last one down, and with just a little wind I got zero penetration and had to land off. (It was a slightly used F-111)

As a student under the 190, it felt slow enough. Only once I was scared of how fast I was coming in because I was downwind. I appreciate that SDC uses "real-world" canopies in their training. I couldn't imagine training under some huge 250+ canopy with a ripcord and then trying to downsize to a "normal" size after graduation. I'm glad I used the same equipment in training that I'd use as a licensed jumper.

However, I do feel like they could've taught me more about canopy flight. I think Roger intended for this, but in my experience, they seemed to neglect it somewhat. There were canopy objectives listed in the syllabus, but none of my instructors ever prepped me for them, or asked about them in the de-brief. It was much more about the freefall skills. (Note: This is just my experience. I have heard others say they got more canopy instruction. )

As far as this chart -- with my new 170 I am over. But like I said, based on many recommendations and my own feeling with the demos I flew, I feel comfortable under the 170. (I actually got a few recommendations for a 150!) I plan to keep it for many years and 100's of jumps. I will also be taking Scott Miller's course in the spring, which I am really looking forward to. I know I still have a ton to learn.
I think this sort of thing is too hard to regulate just based on some static chart. I have seen so many people of different abilities. Some of my fellow students rocked their training and were really good pilots. Others struggled and had many bad landings. (But then they eventually learned and got better.) I think it's a bad idea to make this chart a requirement -- too many variables play into it.

Just my 2 cents.

"At 13,000 feet nothing else matters."
PFRX!!!!!
Team Funnel #174, Sunshine kisspass #109
My Jump Site

[Silverchic 0]

I'm pretty much the same - at the moment I'm in the "black death" range...and will be for about another 60 or so jumps - and have been for the last 20.

How is it that we put man on the moon before we figured out it would be a good idea to put wheels on luggage?

[davelepka 4]

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gathering data on subjects we don't know enough about.

What about the fatality reports from the last ten years? Is there any question that open canopy incidents have made a dramatic increase and risen to become the #1 killer of skydivers? What more do you need to know?

What could the possible harm be to having WL restrictions in place? Wait, let me guess, all the jumpers who insist they would quit jumping if they were limited to a certain WL. Fuck them. All of them.

Lets consider the jumpers who can see beyond the next year of their life. The jumpers who wouldn't quit jumping over a minor, and temporary situation. Lets cater toward those jumpers, and look out for their well being, as they are the future of skydiving.

I would galdly loose 10 or even 20 jumpers who will never make it past 300 jumps, or 3 years in the sport, to keep one jumper alive who will jump for the rest of their life.

The european insurance industry is not relevant here. This is a not a business situation. Nobody stands to make or loose a dime in this situation. I'm quite sure that many would agree that money and greed are to blame for the insurance problems in europe.

There are no alterior motives invovled here. What you have are some highly experienced jumpers who have seen the changes take place, observed the situation, and seen the writing on the wall. In fact Brian Germain stands to loose out in this deal.

It's no secret that training needs to accompany any sort of Wl regualtion to make a real difference. If the USPA were to up the ante with regards to addittional training in the area of canopy control, what do you think that would do to his business? If every jumper was participating in a USPA backed CC course at their home DZ, how many of them would also spend the money on Brians course? Some would, indeed, but the majority would stick with the required and less expensive USPA course.

So what motivations must a guy like that have to donate his time and effort to a cause that could ultimately topple the virtual monopoly he's had on CC courses for the past several years? The answer is simple, it's the right thing to do.

[kelpdiver 2]

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What about the fatality reports from the last ten years? Is there any question that open canopy incidents have made a dramatic increase and risen to become the #1 killer of skydivers? What more do you need to know?

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=1497311;search_string=landing;#1497311

I did that. Oddly, you never commented. Well, no, not odd at all. The fatalty reports do not support you. The non existent femur reports might.

It only goes up to early in 2005, though filling in this year would only reinforce my conclusion that over wing loading was an issue in at most 20% of the incidents. While the easiest to codify and one affecting you in the least, it is not the low hanging fruit.