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SUBJECT : TEETHGRINDER - failure #1

The wind was near perfect, a stiff breeze.

The kite spiralled to the left and crashed repeatedly. On one of the crashes it tore the middle rib down a panel of dacron.

It seemed to pull well, but impossible to control.

I can't imagine that my sewing was so out that it would effect the kite so much (it was like having full left hand down.... actually *more* than that, because it still turned to the left even with full right down... hm...)

So the only thing I can think of is that without the other 4 ribs inflated the LE tube was warping the canope more than the airflow could correct it... I have inflated my AirBlast LE tube first, this then made it almost impossible to inflate the ribs, the LE was twisting the canope too much, so all I can guess is that the same thing was happening with my kite.

Anyway, I've got to unpick the rib from the canope, then down the seam, attach a new panel, unpick the LE tube, split the seam and resew it all together with some extra strength.

The most gutting bit is that I had dacron sewn to the rib that would/should have done the job but I forgot to sew it to the LE tube. I only noticed when I have close the LE tube.... argh! Why didn't I unpick it a bit and fix it?!?!?

ho hum.

On the more positive side, even though the kite was out of control, it never luffed and the whole canope seemed tight. It was only the tips that showed any warping...

The bladders survived it all, even the dacron ribbing and getting dragged along the rocks.

I will post more info on the rip, where it happened and how to avoid it on my web site one day soon :-)

john.e.boy

+--------------------+

Tales of my kite ripping were met with gales of laughter in the office.

Grrrrrrr.

Anyway, here is a photo of the kite before it was damaged:

Please note the lovely assistant.

Here is a picture of the tip of the kite. Note the line attachment points (B) are made from Nylon webbing - like the stuff a bag strap or seat belt is made out of. The curved white section is made from Dacron. Same as the leading edge.

(A) shows how the rib is attached to the leading edge, it is reinforced quite a bit. A more simple way of doing this would be to use some of the Nylon webbing and run it down the bottom of the rib (from the second seam) towards to leading edge, then up the leading edge tube for 4 inches.

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