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Okay, maybe this is a 'duh' question but...

All other variable being equal, will a canopy open faster or slower if it is highly wing loaded or lightly wing loaded.

Or, does wing loading have no impact on the opening shock or how fast a canopy opens?

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I'm not an engineer or anything but I will state that I have gotten wrecked on everything from under 100 sq ft up to 500 sq ft.

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I was told by my rigger that all things being equal, a more heavily loaded canopy will open more slowly, and that all canopies have a maximum suspended weight which, if exceeded, means that canopy simply won't open.

I've not yet read up on the physics of this, so I can't comment further. Hopefully Bill or someone can explain or correct my errors.

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It depends on how you define "all other things being equal." One test is to take a jumper with their canopy, and just keep loading lead weights onto the jumper. The problem with this is that it increases their speed at terminal, which would almost always result in a higher opening shock. If you deploy at equal speed, with more weights, then the opening should would also be higher, since the canopy opening time would presumably be the same, but more force would be required to decellerate the now more massive load.

Your question is actually fairly complex, but I've given a simple approach to answering it.

-- Jeff
My Skydiving History

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First, let's define openning shock. It is the force the parachute exerts on a load to decelarate.
Certain things can affect openning shock such as filling time, porosity of fabric, packing, pilotchute(and therefore snatchforce) etc.

To answer your question, I don't believe that wing loading directly affects the opening shock, but a smaller canopy will decrease filling time and therefore increase opening shock.

As for a overloaded canopy not openning, that probably refers to round parachutes and theier tendency to "squid" when overloaded.

Tim

p.s. If you put more weight under a given canopy i.e. you jumped with an anvil strapped to you, then the parachute would have to exert more force to decelerate your load.

I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

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that all canopies have a maximum suspended weight which, if exceeded, means that canopy simply won't open.

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There's a bunch of stuff about opening shock and things that affect it on here:

www.pcprg.com/

As Darkwing said, this is a very complex dynamics problem.
...

The only sure way to survive a canopy collision is not to have one.

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I have gotten spanked by all sizes of canopies, and don't know if it's "wing loading" to be a factor, but I will say a hard opening on a smaller canopy seems to hurt less than a larger canopy.

I don't know if this is a factor or more square footage, or a heavier wing loading.
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You're not as good as you think you are. Seriously.

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and that all canopies have a maximum suspended weight which, if exceeded, means that canopy simply won't open.

Simply not true.
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You're not as good as you think you are. Seriously.

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To answer your question, I don't believe that wing loading directly affects the opening shock, but a smaller canopy will decrease filling time and therefore increase opening shock.

The counter point to that is a smaller canopy creates less drag and there for will take longer to decelerate a given mass than one with a greater area.

Like I said I've been smacked by a 400 squar foot canopy and by a sub 80 square foot canopy. The 400 felt alot harder.
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You're not as good as you think you are. Seriously.

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that all canopies have a maximum suspended weight which, if exceeded, means that canopy simply won't open.

Slap your rigger and then get a new rigger.
My idea of a fair fight is clubbing baby seals

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I don't know if this is a factor or more square footage, or a heavier wing loading.

It stands to reason that a bigger ANCHOR WILL STOP YOU QUICKER (OOPS) So if the canopy is larger offering more drag then you "should" theoretically stop "faster", i.e. also harder?

But I'm a biologist not a physic geek
You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
My Life ROCKS!
How's yours doing?

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I don't know if this is a factor or more square footage, or a heavier wing loading.

It stands to reason that a bigger ANCHOR WILL STOP YOU QUICKER (OOPS) So if the canopy is larger offering more drag then you "should" theoretically stop "faster", i.e. also harder?

But I'm a biologist not a physic geek

I noticed that the physics geeks were mostly "fearing to tread" where others have rushed in.
...

The only sure way to survive a canopy collision is not to have one.

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Methinks I'll spend some time trying to work through the physics then, if warranted, slap my rigger.

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There are about a million variables.

A big jumper in a tight suit will fall faster than a small jumper; if they both jump the same canopy the larger jumper will tend to have a harder opening. Higher speeds generally equate to harder openings, as do higher altitudes. I had a friend of mine who regularly got knocked out by deploying his MT1X (370 sq ft military canopy) at 30,000 feet.

On a rouge opening, about the only thing that makes any difference is what kind of lines the canopy has, and larger canopies more often have dacron lines (which have a little elasticity.)

Very very small canopies (i.e. sub 70 feet) seem to have a universal problem with hard openings.

There are so many different kinds of canopies it's hard to make any universal comparison these days. Pilots are incredibly well behaved in the opening department; Sabre 1's are pretty ill-tempered (especially pre-1993 ones.)

Bigger sliders? They can slow down the opening (by preventing full canopy deployment for a bit longer) or speed it up (by allowing more canopy inflation with the slider up.) Pocket or dome sliders usually slow an opening down. Leaving brakes unstowed _usually_ leads to slow and bizarre openings; can also lead to lineovers and streamers unless the canopy is designed for it (as some tandem canopies are.)

Personally, the hardest openings I've ever experienced were under Strong 425 square foot tandem canopies. My old Nova 150 came in a close second (before I got the pocket slider.)

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You have a lot of information there. You also referred to the 'Pilot' canopy.

A re-wording of the question... Will a skydiver who weighs 150lbs wearing the same jumpsuit, falling at the same freefall speed, at the same opening altitude elevation, typically have a softer opening on a Pilot 104 or a Pilot 210?

Actually unrelated to this question, this is a very short video clip of a brisk opening I had on a Set 400. http://manifestmaster.com/video/mike.wmv

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>Will a skydiver who weighs 150lbs wearing the same jumpsuit, falling at
> the same freefall speed, at the same opening altitude elevation, typically
>have a softer opening on a Pilot 104 or a Pilot 210?

From my experiences on the Pilot 210 vs the Pilot 117 - they're about the same. The 117 is perhaps _slightly_ harder; it's hard to say because the opening of a small canopy feels completely different from the opening of a large canopy (in terms of hunting at opening time, sensitivity to body position etc.)

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