B. Germains WL chart

[davelepka 4]

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if i jump a 250sf to get that 1.1 w/l i will feel more restricted than you on a 150sf even though we would be at identical wing loadings.

For one, very light poeple do need to make adjustments, as WL produces different results at different points along the scale.

For two, if the concept of jumping anything but what the chart indicated was unkown to you, you would feel no restrictions. Just as the different restrictions for pull alt. for the different licenses, or the need to have a B? license for night jumps. People with an A don't question it, because thats the way it is (I think, I'm so fuzzy on the licenses and restrictions that my facts may be off, but you get the idea).

I'm sure that if we could get a chart in place, it would only apply to those jumpers buying gear from that point forward. Everyone could keep what they had at the time, and downsize as their jump numbers got to the point where they could buy a smaller canopy, and still be within the specs.

[justdumi 0]

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For one, very light people do need to make adjustments, as WL produces different results at different points along the scale.

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Yeah so looking at it from another angle if you take a 1.5 loaded 250 and take a 1.5 loaded 150 and create a "crash test dummy" type scenario, would you get the same amount of damage occuring to the dummies if you cranked both canopies in?

Im thinking possibly not (im not too sure but im just flying by touch here).

In this case then the use of this chart is over simplified to the point where it can be unfair. Surely a jumper loading a 250sf canopy at 1.5 and one loading a 150sf at 1.5 (with equal jump numbers) cant be said to be under the same risk under those wing loadings?

Maybe the chart incorporates a range of ideal/ acceptable w/l for different wing sizes taking into consideration jump numbers?

eg someone on x number of jumps can load a 150sf
at 1.5 but someone also on the same x jumps can be allowed to load a 200sf @ 1.8

(im just using extreme numbers to help illustrate a point here so take that into consideration)

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[Spizzzarko 0]

The 150 size will go faster as there is less drag on that canopy.

I really don't see what all the fuss is about this chart. It's just that... A chart. Somebody sat down with a 6 pack of beers and a buddy and decided to make this thing up. Use it if you want to. A wise man once told me "Regulations are written for the blind followance of idiots, and as a guidance to the truley smart." Can all of you wrap your mind around that one? There are arguments to be made for both sides on this one here guys and gals. Only you are going to decide what you want to fly, and no one is going to talk you out of it once your mind is made up. Only you can decide if you have made a poor choice in canopy size, and need to upsize. If you look at some of the more experienced people here on DZ.com with thousands of jumps, we have a recurring trend in what we post. It will usually sound like this "I don't think the stilletto 135 loaded at 1.3 is a wise choice for someone with 100 jumps". I bet Mr. Blue, Mr. Drennan, Mr. Germain, and countless other people who follow this forum will agree with me on this one. Please don't buy a canopy that deep down inside you know is to advanced for you, but one of your buddies (maybee an instructor) has told you you can get away with. With experience (IE more jumps) comes a sort of sub consciouse ability to fly your canopy. So what seems blatantly odvious to me with 2000 jumps, may not be at all apparant to someone with 200 jumps. That is all.

[chrisgr 0]

Nice quote, but the wise man may not have considered that effective regulations are often combined with education. Education will be crucial to make the regulation stick and will provide some guidance to the ‘blind idiots’.

You said …

“Only you are going to decide what you want to fly, and no one is going to talk you out of it once your mind is made up. Only you can decide if you have made a poor choice in canopy size, and need to upsize.”

If a low-timer doesn’t have the training and understanding to recognize what size/type of canopy is appropriate for them, do you want them to find out the hard way?

The 2K pull rule wasn’t just a regulation that was slapped on us. We have been taught about these rules during our student training and most of us have recognized the real need for following the regulation.

Making the w/l regulation part of the educational process may require you as an instructor to educate your students about the need for the w/l ‘not to exceed’ rule and your help may be required to enforce the regulation.

Are you willing to do that?

[davelepka 4]

I'm not sure how you could read the following and conclude that the 'crash test' would produce equal resutls.

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For one, very light people do need to make adjustments, as WL produces different results at different points along the scale.

Maybe I should have indicated that the 'scale' I;m refering to is the scale of canopy sizes, with the WL being a constant.

This brings up a good point, however, that you would have some confusion as to what I meant. The concept of the smaller canopy producing higher performance at the same WL as a larger canopy should be common knowledge among licensed skydivers. By no fault of your own, you have revealed the deficiency of the educational side of the problem.

Again, this is not your fault, but you may want to consider the scope of your knowledge on this subject before proceeding much further with your argument.

[Steel 0]

This brings up a good point, however, that you would have some confusion as to what I meant. The concept of the smaller canopy producing higher performance at the same WL as a larger canopy should be common knowledge among licensed skydivers.
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Not that I really care to go back and forth here, but if you're going to carry on you need to at least be accurate. That statement was false. Its actually the contrary. The same wingloading on a larger canopy will yield higher performance, as you will move at approximately the same speed but still have more overall lift with a slower stall speed.
Perhaps what you meant to say was that there is more danger in the same wingloading on a smaller canopy because the shorter lines make it more twitching and the stall speed is higher. That would be accurate.
Cheers,

If I could make a wish, I think I'd pass.
Can't think of anything I need
No cigarettes, no sleep, no light, no sound.
Nothing to eat, no books to read.

[davelepka 4]

Nice try, but it comes down to the definition of the word "performance".

In terms of canopy flight it can applied to a measurement of turn rate (and recovery from said turns) OR the amount of lift created. Neither is more 'correct' than the other.

In truth, in the context of the dialouge in which I made the statement, there is a direct implication that my usage of 'performance' was applied to the first definition I gave above.

Edit: I hate to admit it, but I somehow overlooked the obvious argument to support my thoery. Call PD, and ask them what is their highest 'performance' canopy. I would be hard pressed to believe they would tell you the Navigator 300 (or whatever the latgest Nav is). I'm sure that it produces the most lift, and has the slowest stall speed, yet I would bet they would mention the Velo, with it's high turn rate and long recovery arc. I could be wrong.....but I'm not.

[justdumi 0]

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I'm not sure how you could read the following and conclude that the 'crash test' would produce equal resutls.

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For one, very light people do need to make adjustments, as WL produces different results at different points along the scale.

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I didnt. You arent understanding me. I just agreed with you and put my own words to it in the way that i understand...and touched it off with an illustration.

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This brings up a good point, however, that you would have some confusion as to what I meant. The concept of the smaller canopy producing higher performance at the same WL as a larger canopy should be common knowledge among licensed skydivers. By no fault of your own, you have revealed the deficiency of the educational side of the problem.

Again, this is not your fault, but you may want to consider the scope of your knowledge on this subject before proceeding much further with your argument.

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Scope of my knowledge on this subject has been considered and accepted as being reasonable. By no means as wide or extensive as yours but its adequate for discussion purposes.

Every licensed skydiver should know this? How come? I wont say i knew for sure but its something i had deduced myself over time. Not at A license and i didnt see the opportunity for it to have been taught to me by then anyways. Maybe you should say ideally.

What is my argument? My argument is that the chart cannot be used as a hard and fast rule because of the reason that it appears to be over-simplified. Maybe at best it can be said to be persuasive but not binding.

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[davelepka 4]

What I said was, "By no fault of your own", and this was in reference to the holes in the educational process.

If the training in canopy control was as advanced as the canopies are, the concept of WL on different size canopies would be discussed in a formal training session.

Why? Because it's the same principals behind what differences you will encounter when downsizing. Aside from the increase in WL; the shorter lines, and reduced drag will contribute to your performance increases. If you take the increase in WL out of that equation, you are left with two factors that will contribute to a change in performance (as in a smaller person on a smaller chute at your same WL).

This is stuff that jumpers need to know. They are the pilot in command of an aircraft, and need to understand the mechanics behind it. Whats more they are the PIC of an aircraft in an engine-out scenario, and they need to understand the thought process for problem solving and prioritizing whithin a fixed period of time. There are no go-arounds under canpoy.

Look at any other area of aviation, and the certification process for more advanced or higher performance equipment is rigid, and structured. Airplanes, helicopters, and hang gliding all have tiered licensing systems, in which your experience level, and your ability to pass a practical exam, come into play before you can upgrade your equipment. My assertion falls far short of that, to a simple jump number.

The system as it sits now is inadequate. Your lack of information (again, though no fault of your own, and which should only motivate you to support my cause) shows that the educational side is lacking. The stark difference between the way skydivers are given acsess to canopies in comparison to how other aviation persuits control who flies what shows that the regulatory side is lacking,

My suggestion that you re-evalute your argument wasn't meant to demean you. It was meant to show you that you have been shorted in your training, and should feel some contempt for the system that did that.

[davelepka 4]

I feel better having gotten some of that off of my chest. I'm pretty sure I made every point I had several times, and presented them in a variety of different manners, with hopefully everyone finding one they could relate to.

I know that it did help me to clarify some of the thoughts in my head, and line them up in a more orderly fashion.

At this point, in the interest of my sanity, I've got to stop. If you have ongoing objections, please re-read the entire thread, I'm sure I've addressed them somewhere in there. If not, lets keep in PM's, and I'll entertain whatever thoughts you may have.

So thats it. I'm done. I can't resopnd to any more posts on this thread. Except for Steel, because he hasn't had a chance to respond (or he has, and chose not to), his objections really weren't relevant to the topic of the thread, and like I said, I could be wrong...but I'm not.

Thanks for coming out, be sure to tip your waitress...

[justdumi 0]

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The concept of the smaller canopy producing higher performance at the same WL as a larger canopy should be common knowledge among licensed skydivers.

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Sorry i mis-read that to mean that all licensed skydivers are presently aware of that W/L concept.

My bad

Good job on handling the arguments and possibly typing your fingaz to death.

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[frenchyflyer 0]

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[..]
So I guess the point I am making is that resistence to restriction is normal, but should it be implemented a new comer to the sport would be far more accepting of the new rule than those who are already in the sport.

Why well I suspect there are very few people who are within the Max for the chart who would argue against it, but it is those who are over it who are scared to be forced to comply with some new rule which would result in upsizing.
[..]
So basically bring in the table, make some exceptions for those already jumping certain canopies [..]

I think that's the idea:
Let the people fly the canopy they are currently flying (maybe have a S&T O sign them off to prove that they were allowed to fly this canopy at a given time), but enforce such a regulation for all new canopy changes. This will piss off some jumpers who wanted to downsize off the chart, but after a year or two (or 3 or 4) it will be common practice and nobody will question it.
You can also allow exceptions to downsize a bit more aggressively but these exceptions need to be signed by a Canopy Instructor or a S&T O.

The above is basically what was implemented starting last year in France and yes, people were very unhappy at first but things are already settling down.
It is too soon to determine whether this is a coincidence or not but the number of fatalities has decreased this year AFAIK (although only years will tell whether this measure actually contributes to lower the number of fatalities - btw fatalities are not the only issue here, we may be also saving bones and lifestyles).

Note: France is certainly not at a top-level in terms of HP canopy piloting, but we were basically encountering the same issues as you guys with lowtimers digging themselves in under canopies they should have been flying in the first place...

[mattjw916 2]

I am sorry I missed people talking about me while I was outside making about a dozen skydives and amazingly I am still here and not even a scratch on me with the exception of sore shoulders from packing.

But of course, it was all luck... it couldn't possibly have been all the reading, studying, practice, coaching, H&Ps, and perhaps even a modicum of skill.

You know the problem with "one size fits all"... is that it really doesn't fit anyone perfectly in the end.

NSCR-2376, SCR-15080

[raymod2 1]

Ever notice that the BSR's are only two pages long? Let's keep it that way. Brian Germain's wing loading chart is an excellent guideline but I don't think it should be forced on anyone.

[Fast 0]

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But of course, it was all luck... it couldn't possibly have been all the reading, studying, practice, coaching, H&Ps, and perhaps even a modicum of skill.

You know the problem with "one size fits all"... is that it really doesn't fit anyone perfectly in the end.

It could be, but for the most part its hard to know till its too late. Don't worry, I don't disagree with you that some people are better than others just that its hard to know till you are put in a "lose-lose Bigger" situation and don't die.

~D
Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me.
Swooping is taking one last poke at the bear before escaping it's cave - davelepka

[mattjw916 2]

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Ever notice that the BSR's are only two pages long? Let's keep it that way. Brian Germain's wing loading chart is an excellent guideline but I don't think it should be forced on anyone.

My thoughts exactly!

NSCR-2376, SCR-15080

[flyhi 24]

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Ever notice that the BSR's are only two pages long? Let's keep it that way. Brian Germain's wing loading chart is an excellent guideline but I don't think it should be forced on anyone.

Totally agree. It always amazes me how, in a sport that prides itself on the individualism of its base, there are so many willing to stand up and ask for more legislation. The very reason Matt may still be alive is because he got training, read books, talked to those who went before him, and did everything else we call education. If you know the risks and how to avoid or ameliorate them, you are going to be much better off at 3000 feet than if you are only armed with an iron clad BSR.

Shit happens. And it usually happens because of physics.

[chrisgr 0]

Matt got the extra education that he needed because of his own initiative. He overcame a dangerous limitation of many of our current educational and training programs.

You are correct: a w/l not to exceed limit with no educational component would be mere legislation. Hopefully the discussion can continue and emphasize how we can consistently teach those skills that Matt had to learn on his own.

To continue with a previous example … keep in mind that the educational process that teaches us how and why we pull above 2K goes far beyond what is referenced in the BSR’s.

[davelepka 4]

OK, I suvk , and and will reply to this. You bring up a good point, which if I didn't address in the thread, I did consider.

I'm against making this a BSR, but only for the sake of expediency. A BSR takes a looong time to establish, with all sorts of red tape involved. By making this a 'reccomendation' it would speed the process of getting it in place. If it were a 'reccomendation', it could be considered 'standard industry practice' or at a minimum 'emerging standard industry practice', and as the lawyer types will tell you, going against satndard industry practice is a sure way to weaken your waiver if you should end up in court. Keeping in mind the types of incidents I am trying to curtail, that becomes an issue.

The over-riding issue here is that you seem to think that any additional rules in this area are not needed. Do you contend that the current state of affairs is acceptable? Do you disagree that the performance envelope of all canopies has grown considerably, while the training has been stagnent? Are you aware that skydiving is the only area in aviation (as far as I know) that has no tiered system in place to pace pilot ability/experience with the equipment they fly?

[Bartje 0]

ok, we are talking to people who are to fast going to a smaller canopy,
just did say it that you can find your limits on a canopy.

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This is a fact: If your canopy is in proper trim, and assembled correctly, flying it a manner consistant with good canopy piloting cannnot result in a failure of your canopy to perform as expected.

Every canopy what pilots fly good is a safe canopy in that case, it is the pilot who is making the mistakes.

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Furthermore, a canopys max speed can act as a limiter to how much trouble you can get in. If you cannot, or have not flown your 120 at 100%, why then would you want to jump a 107 where you might possibly nail your turn, and reach 100% of that canopies capacity, only to have your experience limited to 75% of a 120? Now you are in over your head. If you had stuck with the 120 longer, not only would have nore jumps, more swoops and more experience, you would not as far out of your envelope if you should hit that 100% on your smaller canopy.

I do not want to fly my canopy 100%, the 101% gives troubles, the 75% is already more than what I see other skydiver get out there canopy.

The chart is a good guideline but pls, I do not hope that it get a rule.

A FreeFly Gypsy

[alan 1]

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But adopting such a WL chart is a snap. Fax a copy to every DZ in the book today, and say, "Starting now, all your students need to be within these guidelines as they get off student status". Done. Over.

Well, not really. You would still have to deal with the people currently out there and have spent money on parachutes that don't conform to your standards. And the issue of all new students and graduates asking about them and saying if they can do that, so can I. It would take some time and a concerted effort.

alan

[davelepka 4]

I think I addressed that up in the thread. It's a long one, and I'm not going to re-read the whoel thing. The idea is that everyone has what they have now, and only when they want to donwsize, do they have to reference the chart.

As far as the new grads go, tough shit for them. At one point AFF was 7 jumps, end of story. One day it turned into 20-some jumps with coaches and proficiency cards and who knows what else ( I can't keep track of it all anymore). There were students who started the day after that kicked in, and they got stuck for 1000's of dollars. All this would do is direct their canopy choices a bit. They would have been buying a canopy anyway, now they just have fewer choices. Besides, from where do they draw the knowledge to make their own choices? They've been instructed on every move they've made on the DZ thus far, so I'd be surprised if there were many objections, and if there were, I'd go right back to tough shit.

Edit- How about the licensing requirements? I know many jumpers who were scrambling to thier jumps in before the requirements went up. Some made, some didn't. I be surpirsed to see one student say, "Dave got his D license with 200 jumps, why can't I?". Change happens, live with it.

Another edit- I agree it would take time and effort, which is why I think this needs to get going TODAY, so we can see some result from it before another Otter full of jumpers goes in with open, functioning canopies.

[davelepka 4]

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Every canopy what pilots fly good is a safe canopy in that case, it is the pilot who is making the mistakes.

I've never seen a canopy do anything wihtout a pilot. With the expection of a few canopies with inherent design flaws (Nova, maybe the Pintail, some early Crossfires) any canopy is safe as fast as a pilot can make it go.

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I do not want to fly my canopy 100%, the 101% gives troubles

101% doesn't exist, literaly or figuratively, in this case. The basic idea is that there is no speed a canopy can achieve which makes the canopy itself unsafe, as in, not structuraly sound (given that the canopy is in tirm, and the pilot is adhering to safe flight manuvers).

The pilot controls how fast a given canopy can go. In the case of a pilot whose skills are developed at or near 100%, he can fly any canopy to it's limit, with a margin of safety. In the case of a pilot who is still developing thier skills (like someone who intends to downsize) the limiting factor needs to be the ultimate speed of the canopy.

Once the pilot's skills are such that the untilamte speed of the current wing can be reached, only then, does it make sense to downsize to wing with a higher ultimate speed. Even then, the top speed of the faster canopy is outside of the pilots experience, but he has come as close to it as possible on his last canopy, and in doing so developed as much experience as he could before taking the next step.

There will always be an element of risk in jumping a smaller canopy then you have previously. The idea is to mitigate that risk as much as possible.

[Fast 0]

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Edit- How about the licensing requirements? I know many jumpers who were scrambling to thier jumps in before the requirements went up. Some made, some didn't. I be surpirsed to see one student say, "Dave got his D license with 200 jumps, why can't I?". Change happens, live with it.

Actually that annoys me some, because there are people who have a D and less jumps than me who can land in the more advanced landing area at my DZ but have less skill. Its just a mild annoyance as I plan to have a D lic soon anyways.

~D
Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me.
Swooping is taking one last poke at the bear before escaping it's cave - davelepka

[davelepka 4]

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there are people who have a D and less jumps than me who can land in the more advanced landing area at my DZ

Thats the DZ management being stupid. If you're qualified for the old D-license, which was the previous criteria for the landing area, you should have access to it now.
The difficulty of landing in that area didn't change, the USPA did.