Kites & kiting

[hazelm]

It went up!  Good deal.  Thanks.

 

I wouldn't want to meet "Bob's uncle" in the dark.  Looks like the critter we found sleeping on our wall one morning.

[LaurieAG]

Short, but schweet!

https://www.youtube.com/watch?v=Bm9y87mFXR8

 

Looks good Turtle, I was wondering if it was going to fly or behave like a wind sock. :)

[Turtle]

I added the 2 triangular wing panels and NASA we have no problem. Now if you rocket sciency aeronautical guys & gals really can control the weather, I want to order up a steady 7 to 12 MPH wind for tomorrow from 10am to 2pm PDT. I promise not to tell anyone you folks did it. :zip: 

What I had today was periodic gusts which for the most part promptly dissipated as soon as I got the kite and camera out. :rant: I did manage a few seconds of recording, and though it doesn't capture what I think are excellent flight characteristics, it gest the idea across.

I'm already making plans to scale up 2x with rip-stop nylon sails and take-down capability. If that goes well, I'll go for a 30x scale up that I can ride in. :D
 

Edited September 28, 2017 by Turtle

[LaurieAG]

I'm already making plans to scale up 2x with rip-stop nylon sails and take-down capability. If that goes well, I'll go for a 30x scale up that I can ride in. :D

 

Make sure it has good handling capabilities as well before you try that one Turtle. Do you have a crash test dummy?

[hazelm]

Come to Missouri.  Missouri has steady winds 24/7/365 and ours are much cheaper than NASA's.  Ours are free.  Or, there is Oklahoma whose winds will really challenge your kites.  But it's hotter over there. 

[LaurieAG]

I did some checking on aluminum, fiberglass, and carbon tubes for the 2x model, but they are all rather out of my price range. Probably will have to go with wooden dowels if I actually get on with it. I'm noodling some ideas for corner/vertex junction blocks that would allow me to take the kite down to a bag of sticks, blocks, and rolled sails. That would be so much better than having to cart around 2ft. fixed square panels.

 

(The prototype struts are 1ft. and 24 are required, so I will need 48 lineal ft. of struts for the scale up. This will give me ~18.5 ft² of sail area.)

 

If the parachute video is any indication this kite might need something like a tail to keep it stable Turtle. Hmm I wonder if there was a specific kite size and lifting capacity that, flying in a >10<20 knot wind, would allow someone like yourself to climb its tail 'ladder' up into the body of the kite? It would also save you from having to wear a parachute. ;)

[LaurieAG]

I completed the new frame with my secret prototype connectors. Because the connectors are not rigid, the structure isn't either. Before I go about adding any tensioning strings/wires, I will see how stiff the sails make the frame when in place. I have a paper pattern for the square sails and will put off cutting any fabric 'til tomorrow. Measure twice, cut once. :) While some kites are pretty forgiving about imprecision in cuts and stitching, me thinks not gonna happen on this bird.

 

DSCN2578b.jpg

For a large scale kite you could just make frames for 2 x square based pyramids with 4 triangular sides and then just join the tips of the triangular sides from one of the pyramids to the tips of the side triangles on the other pyramid. If you do it this way the 4 side squares only appear when you join the pyramids together correctly.

 

What would it look like if you pushed all or some of the tips inwards instead of outwards? 

[hazelm]

Turtle, somewhere above you mentioned  the wind sock.  I have only seen windsocks from their height.  Do they have a hole at each end - one hole being smaller than the other?  If so, that is what I pictured your kite being like at first until you explained.  To keep it up, would the opening where the wind enters have to be the larger of the two?  Then the sides would be closed? 

[Turtle]

Turtle, somewhere above you mentioned  the wind sock.  I have only seen windsocks from their height.  Do they have a hole at each end - one hole being smaller than the other?  If so, that is what I pictured your kite being like at first until you explained.  To keep it up, would the opening where the wind enters have to be the larger of the two?  Then the sides would be closed?

I think Laurie first mentioned the windsock when he speculated that my kite might fly as one.  The primary difference between a wind sock and kite is that the kite develops lift and so it rises and raises its line to an angle above the horizontal, whereas a windsock's line in a wind is at or below horizontal.

 

Windsocks often have a wider opening on the windward side, which serves to puff them up, however perfectly cylindrical windsock will fly horizontal just fine in a suitable wind. The cylindrical wind socks tend to flutter more. Kiters often attach windsocks of various designs to the lines of their kites; they call it 'line art'.

 

There are kites which are inflated by the wind and they get lift because their profile is held into the wind at a similar angle to strut supported kites. (Some ram-inflated kites have wing shaped profiles, such as the parafoils.)

 

Here's a figure kite by the world-famous Peter Lynn. The tentacles are essentially wind socks, and the head is the lifting body. Photo in Wiki article on Kite (Photo Attribution: The original uploader was Clappingsimon at English Wikipedia [CC BY-SA 2.5], via Wikimedia Commons) This kite has a smaller 'pilot kite' above it that holds the air entry open.

 

[hazelm]

Fascinating.   More about the wind than we ever thought there was to know.  I can just see a child with his first kite getting so hooked on them that he gets deeper and deeper into the study, building kites in many different shapes to see which works best and then heading off into a great choice of careers.  This is why my mind keeps wandering off to how wind enables airplanes, parachutes and even wind power.  Birds soaring lazily over the ocean - there is one that can go for days - or diving like the falcon that is literally cutting the air, creating his own wind in a way.  It is all part of a single story - how to use the wind and the air.  For you must have air before you have wind.

 

Thank you much.  Cute critter with his long tentacles there.  I never realized there were so many ways to build a kite. And it is just the start of bigger things.  Now I understand Icarus.  Didn't you ever wish you could be sitting up there on your kite while it flies?  Hang gliding, isn't it?

[Turtle]

Fascinating.   More about the wind than we ever thought there was to know.  I can just see a child with his first kite getting so hooked on them that he gets deeper and deeper into the study, building kites in many different shapes to see which works best and then heading off into a great choice of careers.  This is why my mind keeps wandering off to how wind enables airplanes, parachutes and even wind power.  Birds soaring lazily over the ocean - there is one that can go for days - or diving like the falcon that is literally cutting the air, creating his own wind in a way.  It is all part of a single story - how to use the wind and the air.  For you must have air before you have wind.

 

Thank you much.  Cute critter with his long tentacles there.  I never realized there were so many ways to build a kite. And it is just the start of bigger things.  Now I understand Icarus.  Didn't you ever wish you could be sitting up there on your kite while it flies?  Hang gliding, isn't it?

I have no desire to hang glide or suspend myself from a kite. I injure myself all too frequently just falling from the standing position. :doh:

 In the late 1800's before the Wrights succeeded with their plane, there were quite a few folks building man-lifting kite systems for the military.  

Here's one such, Samuel Franklin Cody: (People still build and fly 'Cody kites'.)

...

Financed by his shows, Cody significantly developed Lawrence Hargrave's double-cell box kite to increase its lifting power, especially by adding wings on either side. He also developed a sophisticated system of flying multiple kites up a single line, which was capable of ascending to many thousands of feet or of carrying several men in a gondola. He patented his design in 1901, and it became known as the Cody kite. ...

[hazelm]

I have no desire to soar on kites either.  I do not like heights.  Yet I can sense what a thrill those who do it get from it.  It looks beautiful from the ground.  I want to read about Cody.  Thanks.

[Turtle]

I have no desire to soar on kites either.  I do not like heights.  Yet I can sense what a thrill those who do it get from it.  It looks beautiful from the ground.  I want to read about Cody.  Thanks.

:thumbs_up

 

Tip: Always carry a small mirror on your person; when your neck gets sore looking up at kites, bust it out and take your relief.

 

I should have the second 3-part sail sewn up today and will put the whole kite together for a test fit. Photos to follow of course.

[hazelm]

:thumbs_up

 

Tip: Always carry a small mirror on your person; when your neck gets sore looking up at kites, bust it out and take your relief.

 

I should have the second 3-part sail sewn up today and will put the whole kite together for a test fit. Photos to follow of course.

Or watching the birds.  Never thought of that.  Thanks for good idea. 

[Turtle]

I used scissors to cut open the plastic bag with 2 screw eyes and 2 nuts. I did not run with the scissors and walked with them pointed down 'cause I learned that in kindergarten. Scissors also totally explain mass, because after you cut stuff you leave a mass on the table. Moreover, the answer to the Universe is not 42, it is scissors.

[LaurieAG]

Bob's yer uncle! A bit more work -and some wind- before I test fly this Flymaxion™. I will disassemble it, clean some label gook off the struts, and paint them. White? Black? Other? I 

 

Don't bother to paint it Turtle, you'll just add extra weight.

[Turtle]

Other musings on kites and kite building.

 

I'm working on touching up the sails and this brought to mind a few things on rip-stop nylon. Even though it is resistant to ripping because of the lattice of heavier threads, it does fray. Fraying in terms of flight adds drag and when this drag is not on lifting surfaces (where it is essential) it reduces the flight performance. Many professional kite makers use a wood-burning iron with a sharp-edged tip to cut the fabric and this seals the edge and prevents fraying. Doing this requires not only the iron, but a straightedge and table that won't burn. A workaround is to [carefully] pass a lighter flame along the edge to seal it after it is cut and that is what I do.

 

Another observation in light of the windsock discussion is that they 'fly' due to drag even though they don't develop any significant lift.

 

OK. Break is over so get back to work!