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millertime24

Question About WLing

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IMHO wingloading is the amount of load that is placed on the wing. This does not include the actual weight of the wing, but does include everything suspended from the wing. We count the weight of the entire main assembly for two reasons
1) Makes calculations easier.

2) lines,risers,toggles,etc. must be accounted for as they are suspended wgt.

So what exactly does the canopy weigh without everything attached to it? Who knows. I would think that it is maybie half the weight in this case 3.5 lbs. so that really wouldn't make any real differance to the average size jumper.

Then again I could be wrong B|



If the weight of the wing is not a load on the wing, what supports it? If you used a lead embedded fabric that made for a 200 lbs canopy, do you think you would still be at about the same wing loading you're at now?

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Your confusing max gross weight with wing loading. Wing loading is the "load" that is placed on the wing. If you have a bare canopy ( no lines or anything) what is its wingloading? Wingloading is the weight that is suspended by the canopy not the canopy itself. The canopy is creating lift therby supporting its own weight and the load or what is suspended from it that creates a load on the wing. If you pull zero g's the wingloading goes to zero not to the weight of the canopy.

At least it sounds good to me. But does it really matter a such a fractional differance? You could take your shoes off and make about the same differance; at least I can with size 13 shoes.
ATTACK LIFE ! IT'S GOING TO KILL YOU ANYWAY!!!!

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But does it really matter a such a fractional differance?



It can!

Estimating that the weight of my canopy is 5lbs, that changes my wingloading from 2.61 to 2.56 which can make a difference in competition. Not as much of a difference as ability and technique, but it can make the difference to some.

Just because an object is generating lift, it doesn't mean that the weight of the object creating the lift magically defies gravity and no longer adds weight to the object. I'm honest having serious trouble wrapping my head around why someone would truly believe that the wing wouldn't be included in the wingloading.
--"When I die, may I be surrounded by scattered chrome and burning gasoline."

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As i said i could be totally wrong. I'm 250 lbs geared up so 7 lbs is last nights dinner.

To me by definition wingloading is the amout of load placed on the wing in addition to the wing itself.

Maybie on of the oem's will post an understandable answer for all of us. It doesn't really matter for me but I am curious.
ATTACK LIFE ! IT'S GOING TO KILL YOU ANYWAY!!!!

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That's why we discuss these things so we can all learn something. Right?



Exactly but I was kind of surprised to see so many people dispute other persons who said the exact same thing who were qualified to answer the question.
--"When I die, may I be surrounded by scattered chrome and burning gasoline."

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Your confusing max gross weight with wing loading. Wing loading is the "load" that is placed on the wing. If you have a bare canopy ( no lines or anything) what is its wingloading? Wingloading is the weight that is suspended by the canopy not the canopy itself. The canopy is creating lift therby supporting its own weight and the load or what is suspended from it that creates a load on the wing. If you pull zero g's the wingloading goes to zero not to the weight of the canopy.

At least it sounds good to me. But does it really matter a such a fractional differance? You could take your shoes off and make about the same differance; at least I can with size 13 shoes.



No, I am not confusing max gross weight with wing loading.

You are right about the zero G thing - but in 0 G's, nothing is being supported - not the wing or the rest of the structure (whether it be an airplane or a skydiver).

The wing loading is the number of pounds of lift every square foot of the wing has to generate in order to sustain flight. The wing has to generate enough lift to support itself and the structure.

What about the B-2 bomber? It is just one giant flying wing! It most definitely has a high wing loading.

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Problem being I am sceptical of everything i read on this site and this sport for that matter. You never really know who is qualified to answer. I have alot of respect for the people on here just I like to absorb what i read possibly try it( not in this case) and then see what I can learn from it. My knowledge is the only thing that keeps me alive so I try to look at both sides even if I don't necessarily agree.

BSBD
ATTACK LIFE ! IT'S GOING TO KILL YOU ANYWAY!!!!

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[The wing loading is the number of pounds of lift every square foot of the wing has to generate in order to sustain flight. The wing has to generate enough lift to support itself and the structure]

Now that makes sense to my tiny little suspicious mind.
ATTACK LIFE ! IT'S GOING TO KILL YOU ANYWAY!!!!

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Problem being I am sceptical of everything i read on this site and this sport for that matter. You never really know who is qualified to answer. I have alot of respect for the people on here just I like to absorb what i read possibly try it( not in this case) and then see what I can learn from it. My knowledge is the only thing that keeps me alive so I try to look at both sides even if I don't necessarily agree.

BSBD



Absolutely thats a good thing. I can see why people tend to think the canopy does not go into the equation. The fact that weight is suspended from a wing makes it seem like its the only part affecting that wing's WL. Just have to remember, that like any aircraft, it is supporting itself as well.
"Are you coming to the party?
Oh I'm coming, but I won't be there!"
Flying Hellfish #828
Dudist #52

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Yes one includes the weight of the main.

But I could see one could also discuss a "payload weight", everything below the links or perhaps the connectors at the bottom of the risers. Just like "how much can I put in this airplane?" one could have "how much am I allowed to attach to this parachute?".

But in practice it is simpler to deal with the all-up weight, which is also what is appropriate to wing loading calculations.

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I was kind of surprised to see so many people dispute other persons who said the exact same thing who were qualified to answer the question.



I'm totally surprised that the question is being debated at all.
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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Before you get on the airplane, all suited up, camera helmet, helemt whatever, shoes, socks, goggles, jumpsuit...everything...even your rig, and then get all on the scale...take that weight...and divide it by the Square footing of your canopies. And there it is baby...the official WL'ing!!

Wade




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But I could see one could also discuss a "payload weight", everything below the links or perhaps the connectors at the bottom of the risers. Just like "how much can I put in this airplane?" one could have "how much am I allowed to attach to this parachute?".



This got me thinking. Is the canopy supporting the full suspended weight because it is descending or is the actual loading varied depending on the rate of decent? Wouldn't the wing loading increase when you flare?


"be honest with yourself. Why do I want to go smaller? It is not going to make my penis longer." ~Brian Germain, on downsizing

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Is the canopy supporting the full suspended weight because it is descending or is the actual loading varied depending on the rate of decent? Wouldn't the wing loading increase when you flare?



Now that's something worth debating :o
What goes around, comes later.

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This got me thinking. Is the canopy supporting the full suspended weight because it is descending or is the actual loading varied depending on the rate of decent?



The rate of descent itself won't change anything as long as the jumper isn't accelerating or decelerating. He's in equilibrium, in his own under-canopy terminal velocity so to speak.

But lift does depend on the angle of descent. Lift isn't automatically "up", for it is defined as perpendicular to the direction of motion, and drag is parallel to that direction.

So if you have a 200 lb skydiver + equipment, descending normally under a canopy giving a 2.5 to 1 glide ratio, the lift vector is tilted about 22 deg. off the vertical. There's only 186 lbs of lift. Since the 2.5:1 glide ratio also corresponds to the lift to drag ratio, there's about 74 lbs of drag.

The jumper is being held up in the air (in constant motion without acceleration) by a combination of the 186 lbs of lift and the 74 lbs of drag.

(If the same jumper is under a round chute that is descending vertically, he technically has zero lift and 200 lbs of drag.)

When the jumper, back under a ram air, is flaring he will need to get the lift of the canopy to 200 lbs when planed out in level flight.

[Edit: This is separate from the issue of increasing the actual load on the wing due to "pulling g" during a tight turn or the part of the flare where the jumper is pulling out from the canopy's descent. All that does increase the load that the wing feels.]

It still makes sense in skydiving to usually just think about the 200 lbs as the load on the wing, even if we keep the whole lift & drag angles stuff in the back of our mind.

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Holy crap! The original question was reasonable enough. But I cannot believe how much this simple idea has been debated!

Include EVERYTHING, physical weight, clothing, goggles, helmet, cameras, container, reserve parachute, main parachute, weight belt. If you take a piss before jumping, you've just decreased your wing loading. If you eat a 1/3-pound cheeseburger, you're just increased it.

When you cut away your main, it falls to the ground. That being known, you should include it in your wing loading. If you have a reserve ride after a chop, youre reserve WL will be lower. If you have a total mal, your reserve WL will be higher.

Simple.

Not so simple. If you increase your wing loading bit by bit. Say you add a pound every ten jumps. At what point do you notice a change?

Also, what about density altitude? Depending on what it is, your wing loading won't change...but it will seem like it did. I call it 'virtual WL'.
"Any language where the unassuming word fly signifies an annoying insect, a means of travel, and a critical part of a gentleman's apparel is clearly asking to be mangled."

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It becomes worth reading,
this is usable in many areas - don't doubt that!

BusLoad, CarLoad, DickLoad... BrainLoad..

When you pick an angle - oh yes, you suddenly get it.

Just for some examples - I prefer:
- mid loaded buses
- low dickLoad girls
- mid to high loaded canopies
- strong loaded liquer
- there's infinite number of defined choices

I Know what I don't prefer flaming.

What a surprise I've had, realising that Gforce was smaller under higher WL (shorter lines), yes it's calculatable - smaller circle, and so on
What goes around, comes later.

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I have always included the weight of the main canopy when designing and calculating wing loading for canopies. The canopy has to support itself in all cases.



It's official then, discussion over.

Now about that how to measure the size of the canopy question...
"If it wasn't easy stupid people couldn't do it", Duane.

My momma said I could be anything I wanted when I grew up, so I became an a$$hole.

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Now about that how to measure the size of the canopy question...



Unless you have a custom made canopy,
why would you question preapproved manufacturer's size?

I guess they agreed on world standard of sizing
What goes around, comes later.

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