DIY - Strutless bow kite

[reyrivera]

have been building my own c kites the past few years. First time building a bridle strutless bow kite. Kite flies fine, but I made a mistake of making the polyurethane bladder too wide for the narrow leading edge. Because of this I could not pump the kite hard enough so it distorts a bit on a power stroke. I might also have made the leading edge a bit too narrow, so I'm not sure if I can fix the distortion during the power stroke. Otherwise the kite flies fine. I think I will play with this prototype a bit more before going ahead and building a 13 meter strutless version.

I call this kite Phoenix, its a 4 meter strutless prototype. The kite does not look clean as I would like it to be because it is 90% made from recycled kite material:

1) Canopy is from other people's broken kites that were going to be thrown away in the trash (two broken 2001 yellow 7 meter Caution spitfires), and RRD pieces donated by Ino.
2) Leading edge is from tent polyester lining.
3) Bladder is from polyurethane bags that I recovered from a construction site.

The only things that are new are: bridles, black nylon ripstop tapes, and v92/v46 threads.

Pictures coming soon

[reyrivera]

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[reyrivera]

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[reyrivera]

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[reyrivera]

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[reyrivera]

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[reyrivera]

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I think I made a couple of mistakes now that I've tested the prototype. Kite distorts on a really deep dive on a power stroke.

Possible fixes that I need to do.
1) Need to undo the bladder and make it narrower so I can pump the leading edge harder.
2) Make the leading edge wider on the next prototype.
3) Change the bridle and support the leading edge a bit more if the first two does not fix the problem.

I will try and have somebody take a video of the kite while its flying. Maybe some of you guys who has physics experience can give me suggestions on how to fix my current issue before I start building a more expensive and bigger version.

Few things that I'm surprised about this build:
1) Light bar pressure
2) Kite is very stable at 12:00 even on 12 mph winds
3) Very easy re-launch on land. Tug one side and the kite will quickly and effortlessly go on launch position.

[kitenaked]

Cool!!!!!!!

[jrg]

Nice job!

I am a fan of the strutless kite idea (I own a 15m 1 strut) except for the swim factor. If your leading edge blows, its a long swim with a sea anchor.

My guesses at fixing your distortion problem are basically the same as yours:
- leading edge dia (the LE on my one strut is massive)
- increase pressure
- change the bridle
- really beef up the corner where the distortion occurs

[ramsey]

I bet if you moved the tow point closer to the center of the kite it wouldn't distort as much. Probably easier to change the bridle a little than build a new kite. I'm sure it will change how the kite flies though.