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USPA and the canopy issue

 

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kallend  (D 23151)

Oct 16, 2010, 12:11 PM
Post #176 of 285 (1345 views)
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Re: [Ron] Re:USPA and the canopy issue [In reply to] Can't Post

In reply to:
Quote:
Which rule takes precedence, then? #1 or #2, when they are in conflict?

When you are on base in your Mooney for 36 and you see a guy on final on 18... Do you turn final on 36 anyway?

.

Happened to me at pagosa Springs, CO. I went around. Unfortunately I don't have an engine in my parachute.


Premier billvon  (D 16479)
Moderator
Oct 16, 2010, 12:27 PM
Post #177 of 285 (1339 views)
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Re: [craigbey] Re:USPA and the canopy issue [In reply to] Can't Post

>How often is a standard pattern used by the FMD at your DZ?

Standard pattern is used 95% of the time. When the first guy down is in a group of people (i.e. not a swooper on a separate pass) it's 99.9%.

> Is it mandated?

Yes, with a few caveats.


Ron

Oct 16, 2010, 8:40 PM
Post #178 of 285 (1316 views)
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Re: [kallend] Re:USPA and the canopy issue [In reply to] Can't Post

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So if two people below you land simulataneously in opposite directions, what do YOU do?

Am I third out of three, or third out of 20?

Am I 20 out of 20?

Quote:
I landed 1/2 mile out and walked back

And that is always a good option.


DaVincisEnvy  (C License)

Oct 18, 2010, 12:22 PM
Post #179 of 285 (1265 views)
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Re: [chuckakers] USPA and the canopy issue [In reply to] Can't Post

Reading the thoughtful responses of so many experienced and respected jumpers makes me a bit hesitant to chime in to this discussion as a total newb, but since I'm nearer the experience level of those who are most frequently killed during canopy flight, I wanted to offer up my experience wrt canopy instruction and canopy flight at small and mid-sized DZ's.

I took a canopy control course at my home DZ at 17 jumps. It wasn't expensive and it wasn't elaborate. The S&TA (an accomplished canopy pilot) taught the course one Saturday morning, and it cost students $50 plus the cost of the HnP's that comprised the practical section. In fact, I completed both of my A-license HnP requirements as part of that course. It was invaluable.

While the basics of canopy inputs and landing patterns were taught as part of my AFF course, there wasn't much emphasis, and I hadn't had much reason to practice those at my home DZ (Cessna DZ, big landing area). In addition to reviewing the mechanics, usage, and applicability of the various toggle and riser inputs, the canopy course also covered inputs to get you back from bad/long spots (upwind and downwind), flat turns, reverse turns, harness turns, flare technique, stalling, tricks to enter the landing pattern when you're not exactly where you want to be at 1000 or 1500 feet, braked approaches/landings, accuracy tricks for landing, how to properly land downwind or crosswind rather than risking a low turn, etc. Our instructor filmed and de-briefed our patterns and landings after each jump.

Like many have said time and again during this discussion -- if the student doesn't have a reason to learn those canopy skills, they won't. And if they don't have an opportunity to learn those skills, they won't. This course wasn't mandated by my DZ, but it was organized and strongly encouraged for new jumpers. I, and the 5 or 6 other students in my class, were eager and excited to learn about the capabilities of our canopies and how to use them safely and effectively. Most pre A-license jumpers want to learn canopy skills! Pre A-license (before students start heading off to new and unfamiliar DZ's) is a wonderful time to teach eager young jumpers the skills they need to survive.

And I'm all for making more advanced canopy training a part of each progressive license or part of the license renewal process. No one should ever stop learning, and I, for one, am already looking forward to taking another canopy control course now that I have my own gear.

I've also taken a few downwind landings to avoid those low turns. I was nervous as hell when I realized I was going to have to make my first one (new DZ, and I mis-judged my landing pattern). But thanks to that canopy control course and discussions with many experienced jumpers at my home DZ, I knew that the downwinder was the better option than a low turn. And much to my surprise, even in 10kt winds, it wasn't so bad. I flared at the correct altitude, had just about zero vertical speed, and slid it out in a cloud of dust like a baseball runner sliding into home. I think it's a pretty good idea for new jumpers to make at least one or two intentional downwind landings in light winds so that they understand that they're not something to be afraid of and certainly not something to avoid in favor of a low turn into the wind.

And I'm sorry I can't remember who posted the comment about mentoring young jumpers, but you are absolutely right. I have been so fortunate to have made some wonderful friends and mentors in the more experienced jumpers at my home DZ -- folks with 1000+ jumps who have always been wiiling to jump with and advise a newbie on topics ranging from buying a responsible first rig to RW techniques to flying and landing safely at new and far busier DZ's. I cannot thank them enough for taking me under their wing and making me a far better, more skilled, more conscientious, and safer skydiver.


(This post was edited by DaVincisEnvy on Oct 18, 2010, 12:24 PM)


grimmie  (D 18890)

Oct 18, 2010, 2:24 PM
Post #180 of 285 (1236 views)
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Re: [Para5-0] Re:USPA and the canopy issue [In reply to] Can't Post

In reply to:
Not to go against the grain the FMD had nothing to do with the broken femur, neck, pelvis..

Ultimately a safe landing trumps FMD. I think maybe a discussion on canopy seperation and giving the fmd enough room so you can safely navigate a pattern would be in order.

I should add I am not a complete advocate for FMD for several reasons all stated previously. I am an advocate for patterns that are predictable. Hence, some standard that all jumpers are well aware of.

It had everything to do with the first man down rule. The jumper was fixated on following the FMD, and lost track of everything else, instead of landing in the pre determined direction.

This isn't the first time a jumper following the first person down has been seriously injured trying to do a last minute correction of direction.

And how many times have we all seen the FMD be two jumpers, going in different directions on a no wind day, landing at the same time????Crazy


MrDree  (Student)

Oct 19, 2010, 1:28 AM
Post #181 of 285 (1202 views)
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Re: [robinheid] USPA and the canopy issue [In reply to] Can't Post

In reply to:
I must respectfully point out that your addition to this discussion defies the laws of physics.

Force = mass x acceleration -- or to say it in English, if you land twice as fast, you hit four times as hard (more or less).

Yours too...

I'm just curious. Based on that formula, can you explain why the impact is four times harder when speed is doubled? Where does that come from? Where is speed in your equation?







Here's a hint:
The right formula for kinetic energy is E = 0.5 * mass * speed^2



peek  (D 8884)

Oct 19, 2010, 4:34 AM
Post #182 of 285 (1181 views)
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Re: [DaVincisEnvy] USPA and the canopy issue [In reply to] Can't Post

In reply to:
Reading the thoughtful responses of so many experienced and respected jumpers makes me a bit hesitant to chime in to this discussion as a total newb...

Your input is appreciated especially since you recently learned the stuff we are discussing, hence my questions below.

In reply to:
While the basics of canopy inputs and landing patterns were taught as part of my AFF course...

What do you think is missing in the AFF course (assuming that much of the canopy control stuff is taught on the later Categories (Levels) when a student is not so overloaded from the freefall part?

Simply missing things that are not in a "canopy course"?
Missing the repetition and review?

In reply to:
.. I hadn't had much reason to practice those at my home DZ (Cessna DZ, big landing area).

Did your instructors tell you to practice those things?

In reply to:
In addition to reviewing the mechanics, usage, and applicability of the various toggle and riser inputs, the canopy course also covered inputs to get you back from bad/long spots (upwind and downwind), flat turns, reverse turns, harness turns, flare technique, stalling, tricks to enter the landing pattern when you're not exactly where you want to be at 1000 or 1500 feet, braked approaches/landings, accuracy tricks for landing, how to properly land downwind or crosswind rather than risking a low turn, etc.

Most of those things are normally covered sometime in your student instruction, probably during the "coached phase". When you say your "AFF course" are you including the coached phase?


davelepka  (D 21448)

Oct 19, 2010, 5:39 AM
Post #183 of 285 (1171 views)
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Re: [peek] USPA and the canopy issue [In reply to] Can't Post

Quote:
Most of those things are normally covered sometime in your student instruction, probably during the "coached phase". When you say your "AFF course" are you including the coached phase?

This is where the bottom falls out of the ISP. Most of that stuff is not taught in the later levels becasuse most of those levels are taught by coaches who never learned those things themselves, and might have as little as 100 jumps.

That's one of the problems with the coach system, is that by this point, many actual coaches went through the ISP themselves, and any shortcomings in the program are doomed to repeat themselves becasue the students are now the teachers. How are they supposed to teach things they never learned themselves?

Let's face it, it takes an in-depth understanding of the subject matter to be able to effectively teach the material. Not everyone learns in the same way, and part of being a good teacher is being able to present the material in several different ways, and indentifying which of those ways is the most effective for one student or another.

Additionally, trying to teach the finer points of canopy control piecemeal alongside of the dive flow for a high-energy freefall jump is a very, very poor course of action. For starters, it's hard to overcome the excitment of a freefall for a new jumper. It's an obvious 'attention hog', and probably the foremost thought on any students mind for at least 24 hours before the jump. To think that you could pepper in some canopy control stuff to the mix, and that the student would give those points their due consideration is just naive.

The second problem with the piecemenal idea is that the majority of the information in a canopy control course is cumulative in that learning one lesson is essential for understanding the following lesson, and so on. When you break it down in to tiny little bits, offered up at indetermined intervals, the 'building block' effect is lost.

When you train a student for freerfall, you are building on skills they already have, and adding only one or two new things. However, you still review the 'building blocks' of skills they learned on previous jumps, such as EPs, body position, altitiude awareness, and pull time. All of these things are reviewed or covered in the dirt dive, but the end result is that everything gets it's due consideration, except the canopy control portion. When was the last time you referenced past lessons in canopy control when discussing new canopy control goals with a student? I'm going to guess it's very rare that this happens, but the freefall related material gets covered and reviewed for every jump.

If you reference post #5 in this 180+ post thread, you'll see that I introduce the idea of a dedicated canopy control course being mandatory for anyone wanting an A license, and that anywhere in the 15 to 25 jump range was the right time for these people to take the course. I provided an example of a new A license jumper I conducted such a 'course' with where I was able to confirm what he did and did not know or understand. Now another new A license holder has taken a similar course at the about the same point in his learning progression, and confirmed that he was largely uninformed, and that the dedicated canopy control course provided a weath of information and the right setting for absorbing that information.

How long should be wait until we realize that this is a good idea? Another 175 posts? Should we follow the USPAs lead, and give it a decade to see how things work themselves out? Or maybe wait until the percentage of jumpers killed under open canopies doubles again? I've got news for you, you can't double 75%, it's impossible.

It's such a simple proposition. Establish a basic canopy control course consisting of 1.5 to 2 hours of classroom time followed by 3 or 4 hop n pops with dedicated learning objectives on each jump. The ISP requires two hop n pops anyway, so all this adds is two hop n pops to the A license requirement. The material would be remedial enough that any S&TA could either tecah it themselves, or appoint a qualified jumper to do so.

It doesn't take a special rating, and the associated ratings course and course directors. It deosn't take days of anyones time or require travel any further than a students home DZ. The calssroom time happens one evening, the jumps are completed the following morning so nobody has to be stuck in a classroom while the props are turning outside. WTF people?


DanG  (D 22351)

Oct 19, 2010, 6:35 AM
Post #184 of 285 (1155 views)
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Re: [davelepka] USPA and the canopy issue [In reply to] Can't Post

The canopy control portion of Categories E-H (actually, of the whole ISP) is to be taught and signed by an instructor. Not a Coach.

Again, you're doing it wrong.


davelepka  (D 21448)

Oct 19, 2010, 6:41 AM
Post #185 of 285 (1153 views)
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Re: [DanG] USPA and the canopy issue [In reply to] Can't Post

Quote:
Again, you're doing it wrong.

I'm not doing anything, just observing what's really happening.

If there's nothing wrong with the training, why are the nuber of fatalities (and injuries) under open canopies continually on the rise? If the system was working, we could at least expect to see a stagnation of the percentage, if not a decline, but that is clearly not the case.

How can you continue to defend the system when the very limited data we have shows a clear failure to perform? You're using the USPA model of, 'Close your eyes and push the ISP, close your eyes and push the ISP, close your eyes and push the ISP'.


davelepka  (D 21448)

Oct 19, 2010, 6:46 AM
Post #186 of 285 (1151 views)
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Re: [DanG] USPA and the canopy issue [In reply to] Can't Post

Insanity: doing the same thing over and over again and expecting different results.
Albert Einstein


danornan  (D 11308)

Oct 19, 2010, 6:52 AM
Post #187 of 285 (1146 views)
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Re: [davelepka] USPA and the canopy issue [In reply to] Can't Post

Just seems to me that training and a perdictable pattern are two different issues. Not hooking it in the pattern is another.

To say that the accidents will be reduced with different of better training is like saying that drivers ed will negate the need for no stop signs at a busy intersection. Training is always good, but rules are needed to make the LZ more perdictable.


davelepka  (D 21448)

Oct 19, 2010, 7:01 AM
Post #188 of 285 (1140 views)
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Re: [danornan] USPA and the canopy issue [In reply to] Can't Post

Quote:
To say that the accidents will be reduced with different of better training is like saying that drivers ed will negate the need for no stop signs at a busy intersection. Training is always good, but rules are needed to make the LZ more perdictable

Maybe so, but the difference is that drivers know how to operate their vehicles. Gas, brake, steering, they know these things, teaching them the rules of the road is the next step.

Until jumper know how their canopies work, you cannot expect them to adhere to rules in the pattern. Teach a jumper how their canopy works, what effects the different controls have over the canopy and how the wind plays into the scheme of things, and then you can expect them to accurately fly their canopy in and around the pattern.

Until such time you can continue to expect jumpers who cannot make to the pattern entry point at the correct alititude, or properly handle their canopy when it's impossible to make it into the pattern.


pilotdave  (D License)

Oct 19, 2010, 7:41 AM
Post #189 of 285 (1127 views)
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Re: [davelepka] USPA and the canopy issue [In reply to] Can't Post

Quote:
If there's nothing wrong with the training, why are the nuber of fatalities (and injuries) under open canopies continually on the rise?

I think the training could be better. But I don't think poor student training is the reason fatalities and injuries are up. The training now is FAR better than it was when I was a student. The ISP has done a LOT to make new A-licensed jumpers better canopy pilots. I'm not saying it's perfect, but I am saying there's only so much you can ask of someone with under 25 jumps. Better student training is not the only answer to reducing canopy accidents. And I absolutely don't believe that canopy training used to be better than it is now... even in the static line days.

Modern canopies are fast and many jumpers are over their heads without even knowing it. They can land just fine. But then they make poor decisions or reactions when things don't go as planned. What they learned when they had 15 jumps has little to do with it.

Dave


DanG  (D 22351)

Oct 19, 2010, 7:48 AM
Post #190 of 285 (1116 views)
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Re: [davelepka] USPA and the canopy issue [In reply to] Can't Post

I never said the ISP is perfect. I'm just pointing out that your criticisms do not accurately reflect the ISP. Furthermore, most if not all of the training you advocate is already contained in the ISP. If there is an implemenation problem, then it needs to be addressed, but saying that the USPA has done nothing to address canopy training since you started jumping in 1995 ignores the very real fact that they completely revamped canopy training. If old school instructors and DZOs don't implement it, then the blame does not lie entirely on USPA's shoulders. USPA can't go around to every DZ and conduct the training themselves, that's not their job. It is up to instructors to train their students, and USPA has prvided at least a good framework for them to use.

If you think you see 'Close your eyes and push the ISP, close your eyes and push the ISP, close your eyes and push the ISP', all I see from you is 'Blame USPA, blame USPA, blame USPA.'


davelepka  (D 21448)

Oct 19, 2010, 8:38 AM
Post #191 of 285 (1095 views)
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Re: [DanG] USPA and the canopy issue [In reply to] Can't Post

Quote:
all I see from you is 'Blame USPA, blame USPA, blame USPA.'

Who esle is calliing the shots around here? From my point of view, even when the USPA puts their foot down in one area or another, the actual implementation out in the real world isn't quite 100%. You'll find some degree of implementation, but you always find that each DZ has 'their way', and they tend to stick to it. So when you look at an issue where the USPA does nothing, you can expect the general population to do exactly the same.

The bitch of the ISP is that is covers both the subject matter, and the implementation of that subject matter, so a failre of either of those areas represents, at laest in part, a failure of the ISP.

The right information presetned in the wrong way at the wrong time is still wrong. My quote from an earlier post -
Quote:
trying to teach the finer points of canopy control piecemeal alongside of the dive flow for a high-energy freefall jump is a very, very poor course of action. For starters, it's hard to overcome the excitment of a freefall for a new jumper. It's an obvious 'attention hog', and probably the foremost thought on any students mind for at least 24 hours before the jump. To think that you could pepper in some canopy control stuff to the mix, and that the student would give those points their due consideration is just naive.

The second problem with the piecemenal idea is that the majority of the information in a canopy control course is cumulative in that learning one lesson is essential for understanding the following lesson, and so on. When you break it down in to tiny little bits, offered up at indetermined intervals, the 'building block' effect is lost.

The ISP isn't new anymore. The open canopy fatality issue isn't new either, and hasn't gotten any better since the ISP. Why else would the ISP include a revamp of the canopy control training other than a reaction to the problem of open canopy incidents, which was well established as a problem at the time the ISP was developed?

The reason is to address the open canopy incidents problem. That problem has gotten worse every year since, so the solution that the ISP was supposed to be clearly isn't working. How long does this odea have to fail before a revamp is called for?

Maybe the scope of the material is correct, but the implementation of the material is wrong. This is why I suggest taking the material, and presenting it in a different way. Don't tack it on to an already action packed, performanced based freefall skydive, give it it's due consideration and hold a proper, focused, canopy control course. Get the information across effectively, and send the message that it's mportant and worthwhile of a student's time and energy.

In the end, the ball is (and always has been) in the USPAs court. Any failure of the ISP, in either material or implementaion is on them, as is the responsibility to recognize that failure and take action to correct it. I am still waiting for either to take place.


DanG  (D 22351)

Oct 19, 2010, 8:47 AM
Post #192 of 285 (1089 views)
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Re: [davelepka] USPA and the canopy issue [In reply to] Can't Post

I actually agree with most of what you've said here. I always thought that the hop-n-pops and solo tracking drives in the early part of the coached section of the ISP were a good time to focus on canopy skills. The freefall portions of those jumps are pretty simple, with very limited goals. I don't think it would be too much to concentrate more canopy work into those 4-5 jumps. It would require the DZ have a dedicated canopy instructor to work with the students and observe them.

The only thing I take exception to in your post is the implication that USPA hasn't done anything to improve open canopy incidents. I think it has, but you may be right that it needs to go further. I'm not convinced that primary education, however, will improve the statistics. Many of the open canopy fatalities every year are experienced jumpers, some highly experienced. A good number come to mind, in fact, that would probably have been qualified to teach a primary canopy course.


davelepka  (D 21448)

Oct 19, 2010, 9:09 AM
Post #193 of 285 (1074 views)
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Re: [DanG] USPA and the canopy issue [In reply to] Can't Post

Quote:
I'm not convinced that primary education, however, will improve the statistics. Many of the open canopy fatalities every year are experienced jumpers, some highly experienced

You can't eliminate the risk of an open canopy incident 100%. Skydiving in itself is taking a risk, and the canopy flight is part of skydiving.

However, you have to consider how long the ISP has been in place, and that students who went through the ISP could, by this point, have significant experience to the point of being instructors themselves. Once a training method has been in place long enough to allow a 'generation' of jumpers to be educated in that method and go on to become 'experienced' jumpers, to some degree you have to connect that training method to the actions of 'experienced' jumpers who went through it.

Even if open canopy incidents aren't exclusively linked to newbies with under 100 jumps, that doesn't mean that the ISP wasn't a part of what eventaully lead to the incident.

I'll just add at this point that the only real data we have is for open canopy fatalities, not open canopy injuries. It's not surprising that the average jump number would be higher for open canopy fatalities becasue, in my opinion, you're much more likely to have a fatal incident once you advance past a 'beginner' canopy. It's just easier to kill yourself, and become a data point, on a 150 than it is on a 190.

When it comes to open canopy injuries, what I see are more low time jumpers. Even minor injuries like twisted ankles or tib/fibs due to overshooting a landing area, or a mis-timed flare are things we need to work to avoid. These 'minor' injuries are sometimes enough to stop the momentum of a new jumper looking to become a 'skydiver'. There's nothing like six weeks on crutches to bolster the argument from family members that skydiving is dangerous, and that the student should stop.


topdocker  (D 12018)

Oct 19, 2010, 10:09 AM
Post #194 of 285 (1044 views)
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Re: [davelepka] USPA and the canopy issue [In reply to] Can't Post

Why are people waiting for USPA to "do something?" IF you see that canopy collisions are causing more fatalies than in the past, shouldn't you be improving your skills in that area? It is your life on the line, not just someone at HQ. USPA is working to help solve this problem, but that will take time to study, implement, and see the results.

Get out there now and learn more canopy control, learn collision avoidance techniques, take a canopy course, learn from those who have been around a while and have seen this stuff for years.

The life you save may be mine too!

top


robinheid  (D 5533)

Oct 19, 2010, 10:24 AM
Post #195 of 285 (1040 views)
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Re: [MrDree] USPA and the canopy issue [In reply to] Can't Post

In reply to:
In reply to:
I must respectfully point out that your addition to this discussion defies the laws of physics.

Force = mass x acceleration -- or to say it in English, if you land twice as fast, you hit four times as hard (more or less).

Yours too...

I'm just curious. Based on that formula, can you explain why the impact is four times harder when speed is doubled?

F = m * a

In reply to:
Where does that come from?

God.

In reply to:
Where is speed in your equation?

F = m * a

In reply to:
The right formula for kinetic energy is E = 0.5 * mass * speed^2

Actually, it's KE = 0.5 * m * v^2, but you're talking flying apples and splattered oranges.

Kinetic energy is a calculation of potential force before a body in motion "comes to rest."

Force is a calculation of how hard a body in motion hits when it does come to rest.

Or to say it again in English:

If you land twice as fast, you hit four times as hard.


(This post was edited by robinheid on Oct 19, 2010, 10:30 AM)


Fast  (D 28237)

Oct 19, 2010, 10:47 AM
Post #196 of 285 (1023 views)
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Re: [topdocker] USPA and the canopy issue [In reply to] Can't Post

In reply to:
Why are people waiting for USPA to "do something?" IF you see that canopy collisions are causing more fatalies than in the past, shouldn't you be improving your skills in that area? It is your life on the line, not just someone at HQ. USPA is working to help solve this problem, but that will take time to study, implement, and see the results.

Get out there now and learn more canopy control, learn collision avoidance techniques, take a canopy course, learn from those who have been around a while and have seen this stuff for years.

The life you save may be mine too!

top

I bolded a portion of your post for emphasis. The problem is that the people on here complaining about this are the ones that are learning and trying to do something about it for exactly the reason of they don't want to be the next person killed because of someone else.

The main problem is all those other people out there who either are too damn sure they know everything, don't think that they really need to know more than they do or are just too lazy to seek out the information. We need to encourage those people to learn this stuff.

I'm also getting sick of being the "bad guy" who has to lay down the law and make these people learn stuff. It just makes people annoyed. If the rules and information comes from the top down, it's not just XYZ DZO being an asshole and it keeps jumpers from just shopping for a dz that doesn't care.


(This post was edited by Fast on Oct 19, 2010, 10:47 AM)


Premier billvon  (D 16479)
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Oct 19, 2010, 10:55 AM
Post #197 of 285 (1015 views)
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Re: [topdocker] USPA and the canopy issue [In reply to] Can't Post

>IF you see that canopy collisions are causing more fatalies than in the
>past, shouldn't you be improving your skills in that area?

Because most canopy pilots believe that they have exceptional canopy skills, and that other people need to improve their skills.


Para5-0  (D 19054)

Oct 19, 2010, 2:21 PM
Post #198 of 285 (984 views)
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Re: [robinheid] USPA and the canopy issue [In reply to] Can't Post

Where does angle of attack come in? You can be swooping at 40 + MPH and use no flare and have less impact than if you fly a larger canopy and come straight down with no flare. Just curious, I am not a psysics guy.
I am trying to say or ask you can impact the ground (if it is measurable in some fashion) harder going slower if the angle is steeper. In fact if the angle is extremly low then I imagine your injury will be more of a ass over tea kettle injury as opposed to a crushing type.


Premier billvon  (D 16479)
Moderator
Oct 19, 2010, 5:37 PM
Post #199 of 285 (937 views)
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Re: [Para5-0] USPA and the canopy issue [In reply to] Can't Post

> In fact if the angle is extremly low then I imagine your injury will be more
>of a ass over tea kettle injury as opposed to a crushing type.

Agreed. But "ass over teakettle" can be pretty bad as well.

Recently we had a very experienced jumper bail at Perris and land downwind in strong winds. He got his vertical speed to zero, but the resulting tumble broke his back.

A while further back we had someone at Brown try to land downwind during Santa Ana winds. He also got his vertical speed to near zero - but then tripped and landed on his head at about 25mph. He died.


robinheid  (D 5533)

Oct 19, 2010, 8:43 PM
Post #200 of 285 (917 views)
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Re: [Para5-0] USPA and the canopy issue [In reply to] Can't Post

In reply to:
Where does angle of attack come in? You can be swooping at 40 + MPH and use no flare and have less impact than if you fly a larger canopy and come straight down with no flare. Just curious, I am not a psysics guy.
I am trying to say or ask you can impact the ground (if it is measurable in some fashion) harder going slower if the angle is steeper. In fact if the angle is extremly low then I imagine your injury will be more of a ass over tea kettle injury as opposed to a crushing type.

It's not angle of attack you're talking about in your example; it's angle of impact.

F = m * a can be a little tricky, because the "a" is for acceleration, which is sorta like speed, but sorta not.

The "a" means how fast your speed changes, or, in other words, how fast you come to a stop.

In the scenario you describe, the force of the swooper landing is distributed over more time so injuries may be less catastrophic, whereas the force of the big canopy landing is distributed over less time, so the injuries will probably be more catastrophic.

And as Bill outlined in the scenarios he described, certain body parts can come to a more sudden stop than the rest of you, with the resulting catastrophic injuries he described.

That's why it's important to slow down your landing speed as much as you can, which is why we land into the wind -- and why we should remember that we can turn in a flare and flare in a turn; if we ever do find ourselves heading downwind, it gives us a fighting chance to get into the wind enough to bleed off some of that extra speed so that we don't end up bleeding (as much) without making everything worse.

Cool


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