February 17, 2009 - Dowel Barn Door Kite Floats Aloft
It's been a while since the last post for a few reasons,
mainly consistent strong gusty wind! That's a bit irritating when you
have just completed a large light-wind kite. Well, today was looking
reasonable with a relatively light prevailing breeze. It was going to be
a very warm day however, and thermal activity was increasing by the
hour, as the sky gradually filled with growing cumulus clouds through
the morning. As the clouds grew, so did the strength of the gusts, but
Aren and I managed to get out early enough in the day to get some flying
in. Down at the Wilfred Taylor Reserve.
Setting up the Dowel Barn Door kite is tricky, and even more so
with a breeze trying to flip the kite inside out while you are fiddling
with the ties! After a few minutes, all ties were in place and I let the
kite float up on a short line. It's such a decent sized thing that no
zoom was necessary to get the photo which features at the bottom of the
How To...web page, although it was cropped down a bit.
With a number of still photos taken, I let out another 20
meters or so of line and let the kite move around against the cloudy
backdrop, in bright sunlight. This made for a nice little piece of movie
footage, some of which now features in the video at the top of the
web-page. A fair bit of zoom, perhaps 2 - 3 times, was used. Wind speed
was just right most of the time, with the spars just starting to bend in
the strongest gusts. Some of the dowel was slightly bowed before the
kite was constructed, which might explain why this kite leans to the
left when the bridle seems to be centered.
Movie making finished, it was time to try and get this kite
high! That wasn't so easy, as the wind speed started to pick up and the
left-leaning problem got much worse. The sail was accurately made, and
fiddling with the ties to shift it left or right a bit would be tricky,
so I just adjusted the bridle. That's the nice thing about kites with an
upper bridle loop! By shifting the Prusik knot across by a centimeter
or 2, it was easy to get more sail area to the left of the towing point.
This did the trick - near the top of the wind range! At the lowest wind
speeds there was still a slight tendency to hang left. Never mind, the
kite now willingly lofted up to over 100 feet as I let out more line.
Unfortunately, the wind problem continued to get worse,
forcing the kite down to low line angles, and bending the diagonal spars
to a horrendous degree! In this state, it would hover and loop slowly
but tightly to the right. The breeze wasn't really that strong, but this
kite is very lightly built with those 4mm spars. In fact, with its
current small wind range I'm a bit worried that it will disappoint too
many people who try to make and fly it. Hence I have jotted down a few
ideas at the bottom of its web page to improve the design. Having said
that, all this kite needs is a light breeze without much thermal
activity. I'm positive it will go straight to 400 feet under those
conditions! Not only that, but it might even be possible to put it up on
only 20 pound line, despite its size. A real light-wind floater!