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Navigator Wing Load Chart

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I have a question about the Navigator Wing-Load Chart on the PD website. I was trying to compare wing loadings to size an appropriate canopy (220 exit weight) and discovered something strange about the Navigator maximum recommendations.

The student maximum exit weight recommendations for the Navigator are:

200sf @ 130 lbs = max wing loading .65
220sf @ 154 lbs = max wing loading .70 [24 lb increase]
240sf @ 180 lbs = max wing loading .75 [26 lb increase]
260sf @ 254 lbs = max wing loading .977 [74 lb increase]
280sf @ 270 lbs = max wing loading .964 [26 lb increase]
300sf @ 289 lbs = max wing loading .963 [19 lb increase]

Here's my chart of computed max wing loadings:
(sf) - Student - Nov - Int - Adv - Expert
200 - 0.650 - 0.700 - 1.000 - 1.200 - 1.200
220 - 0.700 - 0.750 - 1.000 - 1.200 - 1.200
240 - 0.750 - 0.800 - 1.000 - 1.200 - 1.200
260 - 0.977 - 0.977 - 1.077 - 1.292 - 1.292
280 - 0.964 - 0.964 - 1.071 - 1.200 - 1.200
300 - 0.963 - 0.963 - 1.067 - 1.167 - 1.167

The 200, 220, and 240 sizes are consistent (like other PD canopies), but there's no consistency or pattern to the 260, 280, 300 sizes. It doesn't make any sense that the max recommended wing loading would be the same for students and novices, or that the max recommended wing loading would actually decrease on the larger canopies after making such a huge jump between the 240 and the 260.

Just looking at the chart I would be inclined to believe that the chart is misprinted, but the numbers are the same between PD's website, catalog, and Paragear.com.

Can someone make sense of this for me?

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I might just be me, but I can't figure out what you're doing, or why you're doing it? What exactly are you trying to determine with this exercise?

Beyond that, 254 lbs is the tested weight limit for one of the TSO tests for harnesses and reserves, so that might have somethig to do with the suggested loading of the 260. I'm not sure what it would have to do with it, just that it is a significant number in terms of parachute equipment testing and certification.

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I might just be me, but I can't figure out what you're doing, or why you're doing it? What exactly are you trying to determine with this exercise?

Beyond that, 254 lbs is the tested weight limit for one of the TSO tests for harnesses and reserves, so that might have somethig to do with the suggested loading of the 260. I'm not sure what it would have to do with it, just that it is a significant number in terms of parachute equipment testing and certification.


I took the maximum weight recommendation chart for the PD Navigator from the PD website http://www.performancedesigns.com/products.asp?product=na and computed the wing loading for each size of canopy and skill level. The weight limits and wing loadings didn't work out consistently between sizes and skill levels for the three larger sizes of canopy (260,280,300) compared to the smaller sizes as they do with other PD models or other manufacturers.

My Excel worksheet is attached.

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I took the maximum weight recommendation chart for the PD Navigator from the PD website http://www.performancedesigns.com/products.asp?product=na and computed the wing loading for each size of canopy



I'm still stuck on why. Your personal choice of canopy should rely more on what you've already jumped, and the reccomendation of the instructors who jumped with you. If you haven't jumped yet, your instructors will deciede what canopy to give for your first jump, and make further decisions based on how well that first one goes.

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I'm still stuck on why. Your personal choice of canopy should rely more on what you've already jumped, and the reccomendation of the instructors who jumped with you. If you haven't jumped yet, your instructors will deciede what canopy to give for your first jump, and make further decisions based on how well that first one goes.


With all due respect, and at the risk of sounding like a noob Skygod (I've never jumped), how is my question in any way confusing to a 15 year, 5000 jump, D-license holder? This is a fairly simple student level question.

Why is there such a huge jump in maximum recommended wing loading between a Navigator 240 and a Navigator 260 at the student and novice levels?

I've also attached the wing loading charts for the PD Silhouette and Spectre, just click the tabs at the bottom. You'll notice, as would be expected, that the maximum wing loading stays the same based on skill level for those parachutes. The Navigator chart by comparison is inconsistent and counter-intuitive based on wing loadings. It looks more like a printing error.

If I have an exit weight of 220 pounds and then look at the chart:

Maximum Recommended Student Weight
Navigator 200 = 130
Navigator 220 = 154
Navigator 240 = 180
Navigator 260 = 254
Navigator 280 = 270
Navigator 300 = 289

It would seem to me that at 220 pounds I SHOULD BE exceeding the maximum recommended weight for a Navigator 260 even though the chart says that although a Nav 240 has a max. wing loading of .75, I would do okay on a 260 at a .84 wing loading. That doesn't sound like a reasonable increase in wing-loading, actually it sounds like a very large theoretical downsize for someone who hasn't even made a single jump yet.
It's all been said before, no sense repeating it here.

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Dude will you do my math homework? This is a skydiving forum, ask how big a camera you can take on your AFF or how many coach jumps you need to fly a velocity. You are making my head hurt, and it appears you are confusing Davelepka, which usually seems pretty hard to do, so I guess congratulations but easy with all the numbers.

Jump whatever they give you, Nav's aren't all that different between .07 and 1.1 anyway, just don't fly it into anything any you will be fine, flaring is kind of optional on those ;) And don't forget the world would be a better place with less math in it so try being part of the solution and not part of the problem. Good luck on your jumps, dude. And don't read this forum too much before you get some jumps (or even after), I think there might even be a 200 jump minimum to post in Gear and Rigging.

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With all due respect, and at the risk of sounding like a noob Skygod (I've never jumped), how is my question in any way confusing to a 15 year, 5000 jump, D-license holder?



The real answer? Because it's dumb. and has very little bearing on actual skydiving. What you end up jumping as a student depends on several factors, and PDs chart isn't one of them. The real factors range from what the DZ has available, to what is packed, to what the winds are like, to what harness will fit you.

If your body weight is 220, you'll be jumping a 280 or larger. The 260 is too small for you at that weight for your first few jumps. If you prove to be good with a canopy, you might end up on the 260 by jump 4 or 5, if not, you might not see the underside of the 260 until jump 10.

PD never intended anyone to analyze the complete set of data and make those types of comparisons because there's no reason to. What size canopy you jump isn't rocket science. You start off with a really big one, and downsize as you prove your ability to handle the faster wing.

You're sweating the small stuff. What you need to do is figure out a way to get to a DZ and make a jump ASAP. The first jump course (FJC) is designed to take someone who has never seen a parachute before, and teach them everything they need to know to safely make a first jump.

Forget about all this 'research' you're doing, because all that really matters is what the DZ you choose has in their FJC. They will teach you a very specific set of skills that will prepare to jump their brand of student rig, out of their chosen aircraft, following their dive flow for a first jump. Every DZ is slightly different in these ways, and if you muddle up your brain with 'ideas' and 'conclusions' you draw from this 'research', you're more likely to be confused or a pain in the ass during the classroom time.

The only way to be sure you're learning the correct info for the DZ you will be jumping at, is to learn it at the DZ.

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Okay, guy. I will try a simple answer. I'm not sure its the same answer PD would give because they are the experts. I can only attempt a SWAG.

The weights listed are the max weights PD recommends for each canopy. Those weights do not have a linear relationship with the canopy size. They may use exactly the same pattern for smaller sizes and make minor adjustments as they get larger.

Also, as canopies change sizes, line lengths change and performance changes. Performance is also non linear.

Again, this is all general speculation. Dave is really giving you good advice to just chill. The PD designers know what they are doing. So do the people who will teach you to jump.
Owned by Remi #?

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This is a skydiving forum, ask how big a camera you can take on your AFF or how many coach jumps you need to fly a velocity.


Thanks for making me laugh, that was funny. Okay, I'll ask a better noob question:

My exit weight is 220 lbs, would a Katana 107 be a good canopy for my first AFF jump? And, at what AFF level should I downsize to a 97?

There, that'll give Dave something to rant about.
It's all been said before, no sense repeating it here.

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There, that'll give Dave something to rant about.



I was wrong. Don't go to a DZ, or start jumping. Keep 'internet skydiving' poindexter, there are plenty of other canopy WL charts you can analyze and transcribe onto a spreadsheet, then you can stick your sliderule up your ass again, I'm sure the two of you will be very happy together.

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The OP is a Troll with an attitude.

She was researching Alti's 3 months ago.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3978070;#3978070

Now she is researching Navigator wingloadings.

Perhaps in a few years when all the research is done and all the t's are crossed she will decide to show up at a DZ and watch a live Tandem jump be done. A few years from there when she processes all the data she will shop around for the best deal. And finally about the time of their 20 year "first interest anniversary" she will find the most efficient route to the DZ and finally attempt to skydive.

just sayin'...

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Can someone make sense of this for me?



It does look a little messed up, even though PD has some of the most detailed info in the industry.

Nothing wrong with you asking, since you have no way of knowing better. Often, "read the manual" is right, but not all the time.

It just turns out that in this case it is over analyzing things, if the purpose is to figure out what canopy you should jump.

Still, I could see that if you were a drop zone owner about to buy student canopies, it would be a little confusing as the numbers wouldn't match one's own empirical experience.

Even though the jump in recommended wing loading going to bigger sizes is rather large, the lower vs. higher loadings can be PARTIALLY explained. Larger canopies are more docile at the same wing loading than smaller ones, so they can load a bit more. Also, there are practical limits to sizes, so for big guys there's a tendency not to supersize their canopy.

A smaller drop zone might well have one standard student canopy size for everyone, except perhaps a couple smaller canopies for the really light people, and maybe a couple bigger ones for the big boys. It isn't perfect, but different students will jump at quite a range of different wing loadings.

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The OP is a Troll with an attitude.

She was researching Alti's 3 months ago.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3978070;#3978070

Now she is researching Navigator wingloadings.

just sayin'...



I was thinking troll. The knowledge of skydiving is impressive for a whuffo. Don't know how you figured out it was a she though?
Experienced jumper - someone who has made mistakes more often than I have and lived.

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The OP is a Troll with an attitude.

She was researching Alti's 3 months ago.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3978070;#3978070

Now she is researching Navigator wingloadings.

just sayin'...



I was thinking troll. The knowledge of skydiving is impressive for a whuffo. Don't know how you figured out it was a she though?


All trolls are female. It is well-known. Look at petejones45.








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

~ CanuckInUSA

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The OP is a Troll with an attitude.

was researching Alti's 3 months ago.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3978070;#3978070

Now researching Navigator wingloadings.

just sayin'...



I was thinking troll. The knowledge of skydiving is impressive for a whuffo. Don't know how you figured out it was a she though?



My money is off of troll and onto lawyer or researcher for a law firm or insurance firm looking for something[:/]???

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>Can someone make sense of this for me?

Smaller canopies are faster than big ones even at the same loading - thus the lower loading recommended for small canopies.

The 254lb limit is a holdover from TSO C23c (I believe) that limited ALL parachute equipment to 254lbs. Thus it often shows up in odd places.

The numbers above that are all likely similar loadings, just with rounding errors giving you slightly different loadings.

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The knowledge of skydiving is impressive for a whuffo.


I have read and studied the SIM, and I can't find the part about how you have to have failed pre-algebra to qualify as a skydiver. Really, I find it disappointing that something as fundamental to skydiving as the weight to canopy size ratio (wing-loading) would cause experienced jumpers to run for cover. What happens when someone wants to discuss the fuel mileage of their cars?

If anyone just thinks I'm being pedantic (look it up), you can thank John LeBlanc at Performance Designs for that. I've found that PD has the best information on their website, and every article written or video made by LeBlanc does an incredibly clear and thorough job of intellectually discussing skydiving concepts without talking down to anyone about it. I was obviously mistaken when I thought "average" skydivers would have the same grasp of basic skydiving concepts as he does. While I know that other canopy manufacturers produce quality products, I think I would find it difficult not purchasing PD canopies as my first gear.

That said, my OP and my "research" was never intended for selecting a first-jump canopy. I've simply been familiarizing myself with different canopies from different manufacturers, how else does one learn the differences between a Fusion, Stilletto, Safire2, or Omni?

And, if that seems wrong to you, let me just say that it's USPA, DZO's, and lawyers who have determined that I am solely responsible for my own safety, training, and equipment. The shut-up-sign-the-form-and-pay-me-money-attitude of the skydiving industry, SO PROFOUNDLY DEMONSTRATED IN THIS THREAD, requires that I participate in this sport with nothing less than the desire to become an expert in every area of skydiving knowledge. What I don't know could kill me or someone else. It's people like "davelepka" and "likestojump" that leave me wondering if perhaps my money would be better spent on scuba diving trips or building a sport plane. Simply, skydiving interests me, skydivers don't; well, except those like John LeBlanc who clearly know what they're talking about, and can do so at my intellectual level, I actually passed pre-algebra!


--
It's all been said before, no sense repeating it here.

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Smaller canopies are faster than big ones even at the same loading - thus the lower loading recommended for small canopies.

The 254lb limit is a holdover from TSO C23c (I believe) that limited ALL parachute equipment to 254lbs. Thus it often shows up in odd places.

The numbers above that are all likely similar loadings, just with rounding errors giving you slightly different loadings.


Perfect example of what I was talking about in my last post. This is a completely idiotic post from a highly experienced skydiver and moderator. It's outright embarrassing!

The 254 limit is the STUDENT maximum recommended limit, the Navigator 260's MAXIMUM weight limit is listed as 336 pounds! What does TSO C23c have to do with PD's 254 pound recommended weight limit for students? Answer, NOTHING!

The inconsistencies on the chart are not rounding errors, and thanks to my "research" I'm more than aware that a smaller canopy is more maneuverable than a similarly designed larger one at the same wing-loading.



I guess I should start planning that scuba trip to Micronesia.

--
It's all been said before, no sense repeating it here.

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Since we are all morons here, why don't you email John LeBlanc at PD ? Straight to the source...



To quote your own profile:

"And I LOVE telling people how it really is - which usually involves telling them that they are whiny spoiled brats. I also like to rub people's nose into the extremely one-sided, borderline hypocritical statements that so many like to make."

You don't have a monopoly!

--
It's all been said before, no sense repeating it here.

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...how else does one learn the differences between a Fusion, Stilletto, Safire2, or Omni?



Jump them.

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

~ CanuckInUSA

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