Kites & kiting

[Turtle]

It would appear that as long as I keep it light and stay away from airports I'm ok.

 

EDIT: should've waited, could've saved the effort of tracking that info down. CraigD's pretty good with the math stuffs as I recall...generally seems like a decent bloke. should I ask him...I'll ask 'im

 

 

Why don't you ask Craig? :computerkeys: :hihi: He would also know if I'm doing the trig right. If I got C1 correct, then I get the following for C2.

 

 

EDIT: It's possible the minus sign before (D/P) is a typo. I've seen a couple already. :unsure:

 

C2 = -(D/p) * cosh (C1)

= -(11.52/0.0011733) * cosh(0.5016146144159724309580791536331)

= -9818.4607517259013040143185885963 * 1.1284688034136246239705274547244

= -11079.826655863765165039185441426

 

 

or is it...

 

C2 = -(D/p) * cosh (C1)

= (-11.52/-0.0011733) * cosh(0.5016146144159724309580791536331)

= 9818.4607517259013040143185885963 * 1.1284688034136246239705274547244

= 11079.826655863765165039185441426

 

 

Thennnnn...also if I got C1 correct I use it to calculate XK.

 

XK = (D / p) * [sinh^-1((L - W) / D) - C1]

= (11.52/ 0.0011733) * [sinh^-1((25.624 - 2) / 11.52) - 0.5016146144159724309580791536331]

= 9818.4607517259013040143185885963 * sinh^-1(2.0506944444444444444444444444444 - 0.5016146144159724309580791536331)

= 9818.4607517259013040143185885963 * sinh^-1(1.5490798300284720134863652908113)

= 9818.4607517259013040143185885963 *1.2216830548152906878629509132376

= 11995.047124752534496020791375179

 

:coffee_n_pc:

[DFINITLYDISTRUBD]

Why don't you ask Craig? :computerkeys: :hihi: He would also know if I'm doing the trig right. If I got C1 correct, then I get the following for C2.

Invite sent. I'm useless for the complicated math stuffs....have my own weird formulas for sorting things out, but, they only work when I have lots of known aspects to work with...unfortunately this is one area where my experience is so limited that -D.d- math is of no use.

[Turtle]

Invite sent. I'm useless for the complicated math stuffs....have my own weird formulas for sorting things out, but, they only work when I have lots of known aspects to work with...unfortunately this is one area where my experience is so limited that -D.d- math is of no use.

 

10-4 Double-D. :thumbs_up I'm going to go through everything again with paper and pencil rather than Notepad. Besides getting it right for your flight, I want to develop some proficiency in the calcs so I can apply it to my kites.

 

So I finished my Area calculation for the 7ft Alida and with that found her Aspect Ratio. I also weighed her and weighed 10ft of the Mason Line I fly her on. I also made some comparisons between Alida & your delta.

 

Calcs:

 

Ag Top sail panel = 10" X 12.5" = 125"sq

Ap Top sail panel = 125*cos(30 degrees)

= 125*0.866

= 108.25

= 108.25"sq * 2 sails

= 216.5"sq + 125 [back sail]

= 341.5"sq

 

Ag Bottom sail panel = 12.5" X 12.5" = 156.25"sq

Ap Bottom sail panel = 156.25*cos(30 degrees)

= 156.25*0.866

= 135.3125

= 135.3125 * 2 sails

= 270.625"sq + 156.25 [back sail]

= 426.875"sq

 

Ag Wings = 39.5"X40"=1580"sq [790"sq per wing]

 

A = 341.5 + 426.875 + 1580

= 2348.375"sq

= 16.3'sq

 

AR = Span^2/Area

= (91.5^2)/2348.375

= 8372.25/2348.375

= 3.56

 

Weight = 383.2gm = 13.5oz

Line weight = .33gm/ft = 0.0116404074433615oz/ft = 86ft/oz

 

A/W =

= 2348.375/13.5

= 173.95"sq/oz

= 16.3/13.5

= 1.2'sq/oz

 

 

 

Alida Delta-Conyne

Span = 91.5"

Area = 2348.375"sq = 16.3'sq

Aspect Ratio = 3.56

Weight = 383.2gm = 13.5oz

Area/Weight = 173.95"sq/oz = 1.2'sq/oz

Line weight = .33gm/ft = 0.0116404074433615oz/ft = 86ft/oz

 

 

Double-D Delta

Span = 48"

Area = 582"sq = 4.04'sq

Aspect Ratio = 3.95

Weight = 2oz

Area/Weight = 292.5"sq/oz = 2.02'sq/oz

Line Weight = 0.001173333 oz/ft = 852ft/oz

 

Your dime-store Delta has my home-built outclassed. :omg: :lol: My kite is half-again as heavy for its area, I have a lower Aspect Ratio, and my line is 10 times as heavy per foot. :fly:

[Turtle]

I printed out all the Kite related pages from NASA that I have been referencing for the equations and diagrams. While the GUI of computers is great and all, it is no substitute to shuffling papers and laying out multiple pages at full scale. I now have myself 52 pages of shuffla-scala-topia.

 

Here's the NASA source directory again. >>Index of Kite Slides

[DFINITLYDISTRUBD]

http://en.wikipedia.org/wiki/Elytron

 

Your link is a bit hinky

[Turtle]

http://en.wikipedia.org/wiki/Elytron

 

Your link is a bit hinky

 

But I...and the....for a.... . Ah hell. It was a bit hinky. :lol:

 

Meantime, back at my kite bench I'm getting ready to cut some holes in Matilda's wing-spar-pockets in order to attach the cross-spars to the wing-spars. I made a couple new pockets, but as I'm going with the aluminum angle-stock I'm initially going to bolt the cross-spar to the wing-spars so I won't need the pockets. Hope I don't screw it up!! :doh:

 

So, the plain delta kite and the delta-Conyne gain stability when the spars flex and the wings billow up in a cone-shape. A flexible cross-spar may bend too much in higher wind and lessen lift as the cone deepens or the spar may break. A rigid cross spar limits the billow [shallow cone] and the kites can get unstable and dart side to side. I have an idea that I hinted at to stabilize the delta-Conyne while limiting the billow, and that is to add dihedral to the wings. I have never seen this hybrid tweak before and I'm anxious to try it.

 

I annotated my working drawing of Matilda to illustrate. The blue line is a slight dihedral and would require the inner ends of the cross-spar to be joined in space inside the triangular cell. The green line is an extreme dihedral with the wings in the plane of the triangular cell sails and would allow the cross-spars to join at the leading longeron.

 

The more dihedral, the less the projected area of sail and the less the lift, so finding an ideal may take some experimenting. :smart:

[DFINITLYDISTRUBD]

Hrrrmmm, perhaps a rigid spar that is bowed to the desired curve...if one were using aluminium angle, one could bolt (or one who has a TIG welder could weld :D) spars and cross members together with thumb screws and wing nuts (or thumbscrews and captive nuts if one had a welder of brazing capabilities) appropriately placed to allow disassembly for transit. Carefully thought out everything would be rigid enough that twisting of the bowed structure could be nearly nonexistent therefore the kite would hold it's shape under load.

Edited August 8, 2013 by DFINITLYDISTRUBD

[DFINITLYDISTRUBD]

Thanx for driving my curiosity as to the cost of structural aluminium :) Much beneficial information found....I think building a small aluminium boat is in my future.

[Turtle]

Hrrrmmm, perhaps a rigid spar that is bowed to the desired curve...if one were using aluminium angle, one could bolt (or one who has a TIG welder could weld :D) spars and cross members together with thumb screws and wing nuts (or thumbscrews and captive nuts if one had a welder of brazing capabilities) appropriately placed to allow disassembly for transit. Carefully thought out everything would be rigid enough that twisting of the bowed structure could be nearly nonexistent therefore the kite would hold it's shape under load.

 

Putting a bow in a rigid spar just adds weight me thinks. The changing bow & flex is responsive to the wind and lets the kite regain stability. With dihedral wings - I think- increase in wind gets spilled off the trailing edge rather than trapped in the billow.

 

I also thought that if I bolt a rigid cross-spar to the wing-spars, I could shorten it from the taughtness required when using taught pockets. [A bowing cross-spar can pop out of the pockets if they aren't deep enough.] The shortening would introduce an 'automatic' billow as each wing would be a little slack. :shrug:

 

 

Thanx for driving my curiosity as to the cost of structural aluminium :) Much beneficial information found....I think building a small aluminium boat is in my future.

 

I struck a deal with myself to lay off a vice for 2 weeks and instead buy a spring scale. FF to hardware store & they had 2 models. One a 70lb capacity and one a 280lb. No good there. :naughty: I need a 10 to 20 pounder. Next time I try a fishing department.

 

Not to be disappointed altogether, I bought a couple green LED's for starboard wing lights, a 5-function flashing red LED array, 2 small J-bolts, 2 small eye-bolts, a small pulley, and 2, 1" nylon rings.

 

I have been using split-rings -like for key rings- to tie into lines, but they are thin compared to the line and so hard to move for adjustments, and the line can snag the split or even get out the slit. They had brass & steel solid rings too, but I think the lighter nylon is strong enough for my purposes.

 

Oh...priced a 6 foot length of 1/2" aluminum tube @ $11.

 

The all of it pictured below with other necessary tools of the kiter's trades. :Glasses:

Edited August 8, 2013 by Turtle

[DFINITLYDISTRUBD]

Putting a bow in a rigid spar just adds weight me thinks.

Not much really, relatively short addition in length can translate into a fair amount of bow....at least according to sticks I've tried to force into structures too narrow to allow their length...adding pre-bow would also guide any further bowing.

A flexible cross-spar may bend too much in higher wind and lessen lift as the cone deepens or the spar may break. A rigid cross spar limits the billow [shallow cone] and the kites can get unstable and dart side to side. I have an idea that I hinted at to stabilize the delta-Conyne while limiting the billow,

A built in pre-bow courtesy a rigid cross spar would allow a happy medium....possibly the ability to engineer in exactly the bow needed for stable flight.

Should raid the fishin section for kite connectors as well. Swivels are ideal for kiting. No tangles from constantly changing wind direction, no wind up of the line when reelin it in, and quick and easy connect disconnect.

 

 

 

[Turtle]

Not much really, relatively short addition in length can translate into a fair amount of bow....at least according to sticks I've tried to force into structures too narrow to allow their length...adding pre-bow would also guide any further bowing.

A built in pre-bow courtesy a rigid cross spar would allow a happy medium....possibly the ability to engineer in exactly the bow needed for stable flight.

 

Should raid the fishin section for kite connectors as well. Swivels are ideal for kiting. No tangles from constantly changing wind direction, no wind up of the line when reelin it in, and quick and easy connect disconnect.

 

I'll think on the rigid bow some more in light of your arguments.

 

On the swivels. I agree they are good for monofilament and I suspect for braided line as well. However, I was reflecting today on my Masons' Line that I'm using which is twisted. I have a swivel on a snap hook on it that I have been using, but it occurred to me it may cause the line to untwist. :naughty: My line stretches like yours Double-D, but as it does the twist puts an un-twisting torque on the line just like my spinning-disks-on-a-string aka diables or kuas. With a swivel on the line the torque can rotate the swivel and untwist the line and when the tension is removed there is no getting those unwinds back. As it is, with the arm-through reel I'm using, I wind in a while underhand, and then a while overhand to try and maintain the normal twist. Will be removing swivel and just tie into my new nylon ring.

 

That's a wrap. :coffee_n_pc:

 

 

PS Tangent to the engineering side, I earlier lamented that NASA's equation page for Lift needed a Lift Coefficient, but the Lift Coefficient Equation page required the Lift. :blink: In printing their pages I found an equation for the Lift Coefficient that uses the Angle of Attack which I can directly measure with my dangle-ometer. Booya!!

 

>> Kite Inclination Effects: Lift & Drag

 

Lift Coefficient = C_{lo = ~ 2 * pi * a}

 

 

 

 

Edited August 8, 2013 by Turtle

[DFINITLYDISTRUBD]

There any particular reason you are using that line?

 

Maybe it's time to move up to 50# or higher braided fishin line...or perhaps?

 

And interesting read, i'm sure their trying to sell something but is had my attention. http://www.my-best-kite.com/kite-string.html

[DFINITLYDISTRUBD]

OH! I almost forgot! My cousin is giving me her Japanese Fighting kite....she's never had it aloft (tried, but never succeeded in getting it up), and hearing about my high flying adventures she's decided if anybody can get it to fly I can... eagerly awaiting its arrival.

 

Aslo added several more dime store deltas and a diamond to my inventory...considering trying to string a couple together.....also contemplating trying to convert to dual line....but probably not on the latter...idea seems very tangle prone.

 

 

Hrrrrmmmm...Dime Store Deltas, would be a good name for a low budget kiting enthusiasts organization. :P

Edited August 8, 2013 by DFINITLYDISTRUBD

[Turtle]

There any particular reason you are using that line?

 

Maybe it's time to move up to 50# or higher braided fishin line...or perhaps?

 

And interesting read, i'm sure their trying to sell something but is had my attention. http://www.my-best-k...ite-string.html

 

 

Reasons for my Mason Line: Strength, length, availability, price. Will be checking fishing department for both line and a spring scale at my next opportunity. Good article by-the-by. :thumbs_up

 

 

 

OH! I almost forgot! My cousin is giving me her Japanese Fighting kite....she's never had it aloft (tried, but never succeeded in getting it up), and hearing about my high flying adventures she's decided if anybody can get it to fly I can... eagerly awaiting its arrival.

 

Aslo added several more dime store deltas and a diamond to my inventory...considering trying to string a couple together.....also contemplating trying to convert to dual line....but probably not on the latter...idea seems very tangle prone.

Hrrrrmmmm...Dime Store Deltas, would be a good name for a low budget kiting enthusiasts organization. :P

 

 

Never flew a fighter kite, but I have watched them. Anxiously awaiting your reports.

 

On the adding kites, I have retrieved 1 of a pair of 4 foot box kites I won as door prizes 30 years ago at the Fort Warden Kite Retreat. I had given them to the kids years ago and the one I took has a broken spar and is missing all cross-spars so repairs are needed. I added wings to this one, made of left-over purple ripstop from making the rhombox. I bought the fabric at the retreat and I'm suitably impressed by how well it has weathered the decades.(The fabric that is.) Still, I see the Conference' is in it's 32^nd year and well weathered too. Some quick counting finds that I would have attended the premier event and the following year I went as well. Back then I think it was $120 for 3 days of kite everything. Food, bunks, specialty instructors, discount suppliers, a gym full of sewing machines, comradery, and of course, flying kites. The fort sits on the Straits of Juan De Fuca and while wind wasn't certain it was a good bet.

 

Off to waltz Matilda around the shop bench then. Monkey chasin' da weasel. :hammer: Pop!

 

 

EDIT: PS Was reading the Fort Warden page I linked to and they have a link to an article about the premier year. It confirms my suspicion that I was there as there is mention and photos of Nigel Spaxman and I remember him specifically. I still have one of the 3-foot flexifoils that I built under his tutelage, though the all-important tapered spar he custom made appears to be lost. They flew OK, but they always were a little small for the weight of the spar and took a brisk breeze to really perform. The flexifoil is a 2-line controllable kite, in case you didn't know. Nigel was from BC, young then, and a gas to hang with. Still kickin' it with kites Nigel?

 

Here's the story & pics. >> Kite Lines: Fort Warden

Edited August 9, 2013 by Turtle

[DFINITLYDISTRUBD]

Dangit! the site the info for this kite is on is no longer accessible....very much a shame as I'm smitten....very much enamored. I don't know what it is about them but Deltas are my favoritist style kite especially with swept or is it swooped wings (The arched trailing edges....like below)

Though this design is very pleasing to my eye very much too.

 

 

I wonder what ever became of my 16' dragon... and what of the snowflake that pulled so forcefully it dragged me across the field for a bit before snapping the heavy line and disappearing into the cold grey abyss of the November sky.

Edited August 9, 2013 by DFINITLYDISTRUBD

[Turtle]

Moving on, I have some new pics. 3 shots of the aluminum spar connection. Details top & bottom of J-bolt and a wide shot showing positioning. The new cross-spar will set 15" lower than the old wood one. Note the apparent cross-spar is a short test piece only.

 

Then, one shot of the Fort Warden box on the bench. One wing detached, one broken spar, and all cross-spars missing or broken. Not a tear anywhere in the sails though!! These babies are sweet flyers with or without wings. I have in the past flown them in tandem, connected by additional sticks.

 

Kite on! B)

[Turtle]

Dangit! the site the info for this kite is on is no longer accessible....very much a shame as I'm smitten....very much enamored. I don't know what it is about them but Deltas are my favoritist style kite especially with swept or is it swooped wings (The arched trailing edges....like below)

 

 

 

Sweet! Note the double cross-spar. I may come to that with Matilda.

 

 

I wonder what ever became of my 16' dragon... and what of the snowflake that pulled so forcefully it dragged me across the field for a bit before snapping the heavy line and disappearing into the cold grey abyss of the November sky.

 

Thom Benson stole the dragon kite, and the snowflake was found by little Ellen Perry in Wisconsin. :blink: