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swooper81

camber?

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So now that i'm getting into swooping i am starting to read more and more about physics and aeronautics and what ever else pertains to swooping, and had a question that hopefully someone can answer.

does the camber of your wing change when you pull on risers? for example if you pull on the front risers does the camber of the canopy increase?

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I am uncertain of what camber is on a paracute but if it is what I think it is. the curve your parachute has(if you look at it from the front or rear while inflated)?

This is set by the lineset and can be changed by stowing the slider down and lossening the chest strap.

front riser input does however put a step in the camber if only one is used.

My 0.02c

I am also interested to hear about what people have to say.

Aparently JVX's dont like thier camber too flat and I have just ordered one so it will be interesting to see what is said here?
"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

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I am also interested to hear about what people have to say.


That camber is not what you think it is.:P

Camber is the measure from the imaginary line connecting the leading edge with the trailing edge and the highest point on the curve of the wing.
When you move the leading or trailing edge (with risers or brakes), the line between them moves, so I'd say camber would increase.

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Camber is the measure from the imaginary line connecting the leading edge with the trailing edge and the highest point on the curve of the wing.
When you move the leading or trailing edge (with risers or brakes), the line between them moves, so I'd say camber would increase.



Is it considered a straight line in neutral flight or does it curve with the designed curve of the canopy?
--"When I die, may I be surrounded by scattered chrome and burning gasoline."

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Camber is the measure from the imaginary line connecting the leading edge with the trailing edge and the highest point on the curve of the wing.
When you move the leading or trailing edge (with risers or brakes), the line between them moves, so I'd say camber would increase.



Is it considered a straight line in neutral flight or does it curve with the designed curve of the canopy?


I'd say the line (chord) is always considered to be straight, but I'm really getting out of my depth here...

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The camber in aerospace engineering is the asymmetry between the top and the bottom curves of an airfoil.



Ok, that was going to be my next question. Thank you for that diagram.:)
--"When I die, may I be surrounded by scattered chrome and burning gasoline."

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I think that you are possibly referring to "angle of incidence" and "angle of attack" ? These terms refer to the angle at which the canopy "meets" the relative wind, and how you thereby change that angle. If this is what you mean, let me know and I think I can steer you in the right direction. Blue Skies!

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Cool, A picture tells a tousand words;),

What is the curve that is determined by the lineset that is flattened upon opening you chest strap called?
"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

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Cool, A picture tells a tousand words;),

What is the curve that is determined by the lineset that is flattened upon opening you chest strap called?



The terms I've seen are cathedral, or anhedral, or negative dihedral.
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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I'd say the line (chord) is always considered to be straight, but I'm really getting out of my depth here...



That is correct.
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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The terms I've seen are cathedral, or anhedral, or negative dihedral.

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3 results for: dihedral
View results from: Dictionary | Thesaurus | Encyclopedia | the Web

Dictionary.com Unabridged (v 1.0.1) - Cite This Source
di‧he‧dral  /daɪˈhidrəl/ Pronunciation Key - Show Spelled Pronunciation[dahy-hee-druhl] Pronunciation Key - Show IPA Pronunciation

–adjective 1. having or formed by two planes.
2. of or pertaining to a dihedron.
–noun 3. dihedron.
4. Aeronautics. the angle at which the right and left wings or the halves of any other horizontal surface of an airplane or the like are inclined upward or downward.


none of those words fit the bill anhedral means an ununiform shape.

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3 results for: camber
View results from: Dictionary | Thesaurus | Encyclopedia | the Web

Dictionary.com Unabridged (v 1.0.1) - Cite This Source
cam‧ber  /ˈkæmbər/ Pronunciation Key - Show Spelled Pronunciation[kam-ber] Pronunciation Key - Show IPA Pronunciation

–verb (used with object), verb (used without object) 1. to arch slightly; bend or curve upward in the middle.
–noun 2. a slight arching, upward curve, or convexity, as of the deck of a ship.
3. a slightly arching piece of timber.
4. Aeronautics. the rise of the curve of an airfoil, 'usually' expressed as the ratio of the rise to the length of the chord of the airfoil.
5. Automotive. the outward or inward tilt of a wheel, called positive when the top tilts outward and negative when it tilts inward, measured as the angle, in degrees, between the vertical and a plane through the circumference of the tire.



it seems that what i was thinking of is a sort of camber but not the one specific to aviation. atrcraft wings take this curve on but in the different direction. there must be a name for it?
"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

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it seems that what i was thinking of is a sort of camber but not the one specific to aviation. atrcraft wings take this curve on but in the different direction. there must be a name for it?



I gave you the terms, but since you don't like them, so you better start correcting the people who use those terms, such as the author of this paper:

http://www.afn.org/skydive/sta/highperf.pdf

And you need to correct Dan Poynter for his mistake The Parachute Manual Volume 2, page 322.

And J. S. Lingard of Martin-Baker Aircraft makes the same mistake in his paper "The Aerodynamics of Gliding Parachutes"
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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I actually don't completely agree with the definitions of camber that have been given... though I haven't read everything so carefully. Take an airfoil and draw a curve from the leading edge to the trailing edge that is halfway between the upper and lower surface. It'll sort of follow the general contour of the airfoil. That's called the "mean camber line." The camber is the maximum distance (perpendicular to the chord line) between the chord line and the mean camber line (typically given as a percent of the chord).

Course there are probably many ways of defining camber, but think about it this way... a symmetric airfoil, no matter how curved the upper and lower surfaces, has no camber.

Dave

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I didn't know what camber was untill I read this post, but now that I understand it I would have to say ...

YES - Pulling either the front or rear riser would definetly change the camber.

This is one of the thing I find very interesting about a canopy vs a rigid wing. Our airofoils in certain ways are more complicated then a plane wing and in a sence closer to that of a birds wing which is what man was trying to replicate for decades.

I'm going to open a new discussion on flight controls where we can all brainstorm on how many different things we can do to manipulate are wings and their results. Hope to chat with you there.

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Yeah, I only pointed out the symmetric airfoil because if you look at the diagram posted above, it shows that a symmetric airfoil will have upper camber and lower camber. But no matter how much upper and lower camber the airfoil has, if it's symmetric, it will have no camber.

Dave

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