Vienna Kite Festival
After many hours of designing, building, and testing kites the final event for the year had arrived. The Vienna Kite Festival. Held on the banks of an island in the Danube.
The wind was a good 25 knots - well over the wind range of my kites. The crowed was large with a special area cordoned off for professional kite flyers. A colorful array of kites against the backdrop of the Danube and Vienna reels in the crowds. Now the Austrians take kite flying very very seriously. Professional kite flyers have ground tents set up with banners, wind gauges, special reels, and other useless paraphernalia.
I quickly noted that all of the kites in the air were all available on the internet for large sums of money and were all flying at poor azimuth angles (60 degrees at best) due to their low performance high drag designs.
A little about my kites. They are cheap, using plastic drop sheets with wooden dowels held together with packing tape. The line winder is home made. All holes are made using a red hot poker over the BBQ (no drill available). So they look pretty rough but fly very well due to the hang glider roggallo low drag high aspect ratio design. The computer modelled design minimized the weight by calculating the stresses on the spars and sails allowing minimal material selection.
The only expensive bit is the line, as it has to be low drag and strong. The benefit of cheap materials is I can afford to lose them. And I have lost many. (Most in Greece over the Mediterranean at night.)
Back to the Vienna Kite Festival. I set up kite number 17, (a super high aspect ratio design just finished an hour ago and never tested), away from the pros. I chose this kite simply because it looks a little more professional than the others being a plastic table cloth with "Thomas the Tank Engine" on it. (an attempt to get the kids interested) The other two are clear plastic "Wright Brother" looking contraptions. With a fast launch I quickly got to 150 meters with the kite flying directly above, it looked to fly stable when bang, the thing exploded in a spectacular fashion spraying bits of wooden dowel and plastic over the onlookers. Many OHHS and ARRRs were heard as the debris fell to earth.
Next was kite Number 14. A high aspect ratio light wind kite with clear plastic sheet. Another fast launch 150 meters this time it climbed to windward of me before dropping back and catching a gust at just the wrong angle. The kite darted sideways at an incredible speed leaving the line trailing well behind when again bang and subsequent spraying of kite bits. The Vienna Kite Festival crowd was well entertained with cheering and clapping this time.
Next was kite number 15. A low aspect stable light wind kite. I adjusted the bridle for less stress and hooked it on the line. This time I noticed the small gathering around me had grown with some very keen onlookers all gibbering in German. (The only fool to make his own kites.) It was at this time I realized I had torn jeans and with the home made kites must have looked like a poor Hungarian.
Up she went to 200 meters in a few minutes. With the adjusted bridle kite number 5 out performed everything in the air flying directly above and regularly flying to windward. A good 15 minutes of stable flight showed what these kites can do. Then, I noticed that it started to develop a slight turn to the right.
A few minutes later the kite was drifting toward the professional kites. I noted the public address system music had been replaced with a Vienna Kite Festival official. The slight turn had now developed into a spiral in the gusts which I could correct by letting some more line out in the dives and pulling in when straight. The thing was performing like a dive bomber at extremely high speeds for a kite. The line was emitting an audible scream due to the tension and wind. The voices over the PA were getting louder.
After several minutes of climbing and diving I finally tangled someone else's kite line. Trouble was with this tangle I lost any control and ended up tangling another two kites. The tangle held for a good five minutes when the first kite string broke sending a blue Cody box kite into the Danube (€270). The crowd cheered. A minute later and a green Dragon had the same fate (€174). The crowd cheered again. Finally my line broke and off to the river went number 5 (€2). The cheering was noticeably louder.
I left the park very quickly.