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dimbohall

ideal canopy size

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You have to start with an assumption to disprove -- howzabout you disprove that larger canopies are a better choice for students?



Easy. There is a too large. Probably something close to one or two thousand square feet. You'll lose your ability to control the thing and choose where it lands.

A plausible example is in my case the 230 I was given on my AFF Level 3 jump. The winds had died down on the ground enough for students to jump. The winds at 3-5k were still blowing strong, however, and this wasn't known till another student and I got blown more than a mile off the landing area. I landed in a tree farm. Fortunately the trees were only a couple feet tall.

Safety is not the only consideration. Buying too large is a waste of time and money that could instead be spent on jumping and building experience. This is an absolute loss, even if it is small compared to hurting / killing yourself on a way too small or way too large canopy, or not jumping at all. It ought be measured against an correct choice, not against another poor choice.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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Nobody is going to tell you to go ahead and make a risky decision because we live in a litigious society and as a community skydivers are terrified of lawsuits.



Hmmm, Is that one of those gratuitous assumptions you were talking about.

I've got an idea, how about we don't criticize the post but instead discuss the issue. WOW what a novel idea!

Seeing that I own a DZ that also teaches hang gliding, maybe I can ad some consideration to the pot.

First, it should be noted that Paragliding pilots will often under shoot. It's one of the great predictable outcomes when one is transitioning to skydiving. They are simply not used to the sink. Paragliders and Parachutes fly very differently, for example, a skilled pilot can loop d loop a paraglider! Really, I shit you not. The Hang gliding instructor at our site has this video ...

Secondly, going from a paraglider to a Manta is radically downsizing! Let alone a 150, no matter what the wieght.

Thirdly, while to canopy pilot will be above average in confidence, and flaring (we will bug you mercilessly if you don't stand up!:P) An unfamiliar canopy will increase your risk when landing off the DZ.

Now that being said, here is what this canopy pilot can bring to the party.
First he'll be much more situationally aware than a regular student and far less intimidated by altitude.
Second, he'll be able to progress far quicker than someone with no experience.
Finally, if he is familiar at all with the RCR, he will probably possess safety awareness that would embarrass 95% of the skydivers out there today.

In the end, we can't judge this jumper without assessing his skills, but we can talk about what there is to consider.

By the way, if a 190 flys like a bagged out paraglider, and bagged out paragliders drop out of the sky like stones, how would a 150 be an improvement? It would sink even more! If you want more performance, I've got a 396.....;)
I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

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The correct choice is a continuum -- it depends on whether the student is having a good day, the winds on that way, along with the student's weight and experience level (that day). It would be hard to settle on the perfect answer for any given day, and my submission is that it's better to err on the large side.

I have several hundred jumps at about .5-.8 lbs/sq ft. I would be very hard pressed to call that more dangerous than 1.1, or higher than that. Errors are possible with each choice, and you just have to choose what class of error you're willing to have your students live with, or suggest to them as being ideal when they buy gear.

Wendy W.
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)

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There is no excuse for hitting an obstacle. none. period



Tell me then, why does the SIM bother requiring the designation of landing areas that are free of obstacles & of sufficient size / shape, if there is never any excuse for hitting them? It's not a bright thing to do but the point is not to feel sympathy for me but to understand that a smaller canopy would likely have been a wiser decision under the circumstances.

The general case of landing off is less safe than landing on, can we agree on this? Or perhaps the main reason for designated landing areas stems from land-usage rights?

Not jumping at all would not be a satisfactory answer because the SIM criteria for student jumping had been met. There was no reason not to jump, and there was every reason to jump in that I was a student and I wanted to learn, and the DZ was right there and they were willing to teach a student.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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I cant believe that you can honestly blame a canopy for an error. That is the type of excuse that burns my ass.
I landed off cause my canopy was to big.
I crashed my car cause it was a ford.
The other 7 guys went the wrong way on a donut.

Take some responsability for chrissake.

Ever heard of spotting?
Ever heard of winds aloft?
Ever heard of finding your outs?
Ever heard of target fixation?

No .... must be the canopy. Sad.

Without some responsibility, it'll happen again and again. I've seen experienced jumpers run back to the DZ, turn around and then fly backwards another 1/2 mile. They acknowledge the error, they don't blame the canopy.

True you had low experience as a student, but I gaurentee you that blaming your canopy is intellectually lazy. I'd like to see an arial view, I'd bet there were a couple of outs.

By the way, I've suspended student jumping when ground winds have been 7 mph because of the situation you were in. Damn the minimums they are guidlines. They do not trump common sense.

One last time. Your canopy size was not the reason your spot sucked or you wound up without options! If a DWI can hit the peas with a 0 forward speed and 30knt wind so can you. Even if you were jumping a C9!
I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

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you just have to choose what class of error you're willing to have your students live with, or suggest to them as being ideal when they buy gear.


I agree with you on this, only I think that it's a good idea to take the student's preferences as an input to whatever black box process it is that leads to a recommendation. The same 0.8 that makes your day could stifle some else's. Even at the expense of a degree or two of safety.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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I cant believe that you can honestly blame a canopy for an error. That is the type of excuse that burns my ass.



Who's blaming the canopy? I was the one who stepped into the harness, it was my responsibility from that point forward. Using a smaller canopy would have been brighter tho. Getting out of the plane 1.5 miles after everybody else could also have done the trick.

Landing in a tree farm /was/ an out, since the trees were small. It was that, corn, or houses and a row of trees, or a road with low voltage power lines. The tree farm and the corn were outs. Go go gadget monday morning quarterback!

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By the way, I've suspended student jumping when ground winds have been 7 mph because of the situation you were in. Damn the minimums they are guidlines. They do not trump common sense.


And in this case all common sense pointed to going ahead and jumping. At least 4 AFF instructors and the manifest staff thought so. Previous loads hadn't had a problem, tho they most likely opened at or below 3000ft, and so didn't experience the winds.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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Who's blaming the canopy?


Well it's good to see a sense of responsibility but you were making an argument about larger canopies being less safe than smaller ones. There were three factors in your story. 1. large canopy 2. high winds 3. off DZ landing.
Ergo large canopy = less safe in that scenario.

That story is an equivocation, however, as it does not state all the facts and considerations.
You deliberately omitted facts to make your point as you have now admitted that there are other factors to the incident in question.

To equivocate the same story to the opposite point;
You had a bad spot, landed off the DZ surounded by obstacles. Thank god your chute was big as a smaller chute would have been more difficult to maneuver close to the ground. The incident reports are, after all, full of inexperienced folk landing off with small canopies and injuring/killing themselves.

Don't piss on my leg and tell me it's raining.
I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

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You deliberately omitted facts to make your point as you have now admitted that there are other factors to the incident in question.


I also didn't say it was a Sunday, it was the afternoon, and the winds aloft were from the West...how is any of this relevant? What other fact am I admitting that I am also concealing?
Maneuvering it close to the ground is not relevant because the winds were low below 3000ft or so and my approach was sound. I was at less than 0.7 on the 230, it would have been reasonable by anybody's measure to go up to 0.8 or so on a 190. In fact I wound up flying a 190 a couple jumps later.
A smaller canopy would have provided a larger margin of error in which to land on the DZ. Landing on the DZ is broadly safer than landing off the DZ, all things considered.
Do you have any more more Monday morning calls? What else did you see when you were not there?
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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I can come up with some ideas
* a smaller canopy wouldn't have flown faster (probably still backwards tho) in the headwind
* a smaller canopy wouldn't have descended faster through the altitudes with high wind
* I wouldn't have been able to spiral on a 190 (I could barely on the 230--I'd done pullups on the risers in AFF1 or AFF2)
* I would inevitably have hooked it in if I had the temerity to fly a smaller canopy that than someone on this board recommends
but I can't agree with any of them.
^^ important edit up there. oops
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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I don't even have 100 jumps, but that's 100% Bullshit.


Go on, tell us why it is bullshit.



You stated that the winds were doing very little below three grand. If thats the case, then a smaller canopy WOULD be more difficult to put spot on a target when having to land in the city or something. As an extremem case, for an example, it would be like saying a Velocity 103 is easier to land on a small target than a 230. Which is complete bullshit. The forward speed in low or no wind conditions of a smaller parachute makes it much more difficult to shoot accuracy. PRO ratings have minimum canopy size requirements for this reason.

You had a valid question to start out and everyone seemed to provide relavent and tactful feedback, but you were on the defensive about each reply.

I had a pretty agressive canopy progression and managed to survive it, although I was out for a few weeks one time due to a low turn that bit me, HARD.

Experience IS relavent. It was relavent for him to say that he had 150 hours per year under a paraglider. It was relavent for riggermick to state his time in the sport and waht he has seen. I've only been jumping for 4 years and have known a person per year who died. All of them had good canopies above their heads.


Cheers,
Travis

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Velocity 103 is easier to land on a small target than a 230


But it's not a question of a 103 vs a 230, it's a question of a 230 vs a 190. A 230 which put me ~1.5 miles away from the dropzone, whereas a 190 would definitely have gotten me closer. Hell the other guy just weighed more than me and he ended up closer to the DZ by way more than his separation from me...I could see the distance between us growing under canopy facing back to the DZ as we were being blown backward (he was an AFF1 on a similar 230, and exited after me).

It's not a linear system by any matter--in all likelihood I would have broken my leg or something on a velocity 103 instead of a sabre 190 or a PD-230 or whatever it was.

wmw999's question was whether there was any way a smaller canopy could be better than a larger canopy for a student, and I stand by my example.

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Experience IS relavent. It was relavent for him to say that he had 150 hours per year under a paraglider.


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

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Now you are being deliberately obtuse.
Does Sunday have relevance to making back to the DZ? no
Does Spot have relevance to making it back to the DZ? Yes
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Maneuvering it close to the ground is not relevant because the winds were low below 3000ft or so and my approach was sound.



Oh yes and when you are coming down into the shit, with winds dropping, a smaller canopy with a faster forward speed is always a good idea:S. By the way, when you are landing off, there are obstacles you may not see until you are 100' away from them. That's when you want a big monster to flat turn yourself out of trouble.
You do know what a flat turn is, don't you?

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A smaller canopy would have provided a larger margin of error in which to land on the DZ. Landing on the DZ is broadly safer than landing off the DZ, all things considered.



Ah yes, a smaller canopy to make up for mistakes.
What a great idea. What a clever guy you are.
I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

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Does Spot have relevance to making it back to the DZ? Yes


Who chooses the spot on an AFF3?
At my DZ it's the instructor. edit to add: and just so you don't think I'm pawning off responsibility again, I explicitly take responsibility for his decision. It was still my idea to show up, pay the bill & step out.
It's really not that uncommon for us lightweights to end up in a situation where we're flying backwards under large and not-so-large canopies. It happened to me a few times under my 150, even.
I'd generalize the contention to anytime that you are flying backward (edit with conditions) in moderate winds and/or at a < 1.0 WL(/edit) you're probably better off with a canopy one or two notches smaller, if you're not already on the edge of your ability to land the thing.
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a smaller canopy with a faster forward speed


a 190 with 160 lbs underneath it does not have a fast forward speed. Well maybe compared to a 230 that's moving backwards.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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Hi everyone again, and thanks for all the replies.

It is interesting to note the huge variety of replies. Perhaps I should clear up a few things:

1) I have no interest in swooping, and am unlikely to in the future. I get all the canopy kicks I need in paragliding and don't wan't to dampen my reactions as paragliders have to be flown more delicately (risk of flat spins, locked in spirals, collapses, crevattes, stalls, falling into canopy)

2) For the above reason, I can't forsee ever wanting to downsize further. My pack will be a reasonable size and that's good enough for me.

3) I am used to flying comps, and therefore am used to having 100+ canopies around me within the same thermal. Awareness is not likely to be a problem.

4) Given the above, being forced into a low turn is not likely. Collisions are not likely. Flaring high then letting up to nose dive into the ground is not likely. Landing where I don't want to is very unlikely. Turbulence affecting me is very unlikely.

5) Those of you that have flown paragliders will realise that they fly very similarly, and that the experience is very relevent.

Lets do a sum:

canopy sink rate=4m/s (for the purposes of sum)
pull height=1200m
canopy open 1100m
+-4 mins of descent (assuming pretty much no turns)

my hours under paragliders = 1500 hours

time to accumulate this flight time in skydives=22500 jumps (assuming no tight turns, spireals etc.)

Is this not relevent?

I'm not posting here to prove to anyone how good I am at anything. My reasoning is that it would seem a waste of time and money to buy a 170 and then downsize to a 150 when I am 100% confident that I would have way less problems downsizing than somebody with 150 jumps=10 hours (assuming they make no turns in the descent!)

6) I understand all of your concerns, and made this post to guage the general reaction among skydivers. If there is anyone out there that has done a lot of both skydiving and paragliding - LET ME KNOW WHAT YOUR OPINION IS.

7) Nobody here has suggested a scenario that seems at all likely to me-or at least more likely than for your average joe downsizing after 150 jumps. Please outline the biggest dangers of this scenario as you see them.

THANKS.

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It's hard to talk about particulars of this case since the OP provided next to no information that could be used to give him advice, so instead we all start making gratuitous assumptions.




Did ya read my post? All of it, or just parts?

Here's a reminder:

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the DZ he jumps at has given him a 190 to jump at the 25 jump level. Provided he's an exceptional pilot (which he claims to be) it only stands to reason that the DZ would have him at an above average WL. IF that puts him under a 190, we're looking a weight of at least 170 lbs. Add gear and his WL on a 150 is out of the question for a guy with 25 jumps.




With that in mind, and yes, it is an assumptionm it would be foolish to err on the side of risk as opposed to caution. The only hole in my logic is that he's nto regarded as a good pilot by the DZ, and they have him at a lower than average WL, giving him a lower bodyweight, providing a more reasonable WL for the 150. The catch is that he's not a good pilot, making the 150 a bad choice.

This isn't rocket science friend. Look at the facts presented, pull whatever usable info you can from them, and make a judgement based on that.

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it would be foolish to err on the side of risk as opposed to caution edited with the rest of davelepka's quote


It would be foolish to err if we could avoid erring altogether just by working with the poor guy instead of dictating someone else's preferences to him.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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Are serious? Could you remove any more context from that statement? You made it almost 100% pointless. Here I'll show you:

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remove any more



See how you take a complete sentence, and make it useless by removing the context?


"It would be foolish to err"???????


If thats not the most foregone conclusion, I don't know what is. Why not quote the whole sentence, or at least enough of it to make a complete thought, and then react to that?

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Alright I edited the quote since you didn't like it. The bit I originally cut out was the bit that got me thinking.

There's two concepts from statistics that are useful in classifying ordinary every day errors.

* bias, or accuracy: Telling people they should always go large is an example of inaccuracy / bias.
* variance, or precision: Telling people we're not quite sure what they should jump because we don't know them or their gear is an example of variance.

Sometimes by changing the way we think we can eliminate or reduce one or the other of bias or variance without changing the other. And it is almost always desirable when we can.
My advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski?

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There's two concepts from statistics that are useful in classifying ordinary every day errors.

* bias, or accuracy: Telling people they should always go large is an example of inaccuracy / bias.
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OK, well you're confusing the science of statistics with this other thing called reality.

It's quite common, especially when it comes to downsizing, that a jumper wondering if it's a good idea, will simply keep asking around unitl they get the answer they want. This goes as far as jumpers are not permitted to jump a canopy at one DZ, for saefty reasons, will simply up and go to another DZ where they are not known, and can jump what they please.

What you're dealing with her are type A personalities, comfortable with taking risks. Jumpers want to go fast, and if left to their own devices, many of them would make extremely bad choices. The primary factor keeping that from happening is the accepted norm for canopy sizing, which in itself is very open to variance.

What it boils down to is this: In these situations, you need to close all possible doors to the idea of downsizing unitl you have first hand knowledge that this is an appropriate course of action. If you leave even the remotest possibility open that it's a good idea, the jumper can construe that as consent, which turns into an online purchase of a small used main, and the aforementioned search for a DZ to jump it at.

The answer always need to be 'no' unitl it's clearly a 'yes'. How do I know this? How about a decade of watching it happen over and over again. A decade I spent the better part of as a professional full-time skydiver, working with students and newbies all along.

This is where you can look to my first post to you where I said:

If a guy with 5 jumps had a valid point, which he explained sufficiently, I would put his experience aside, and consider the point on it's own merits. Conversely, if a guy with 5000 jumps had a point which he couldn't explain very well, I might use his experience to give some extra consideration to the point.

***


In this case I appear to have a vaild point, which I have explained in a clear manner, and the experience to back it up. It's the tri-fecta of DZ.com.

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It is clear you are not looking for an educated opinion but just what you want to hear.

You want to hear this:

"Given your paragliding experience, your skydiving canopy experience is way above your jump number so go ahead and get a small canopy"

The truth is:

"Given your paragliding experience, your skydiving canopy experience is in line with your jump number even though your overall flight experience is not, this might help you but can also hurt you".

Skydiving and Paragliding are not isomorphic systems, not even weak homomorphic if you asked me.

Bottom line:

Use your experience, do not let it use you
Memento Audere Semper

903

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