Harald Prinzler
Mikroelektronik, Fesseldrachen und Fotografie
Detmolder Straße 93
D-33175 Bad Lippspringe
Phone: +49-5252-7830
email: harald@hprinzler.de
URL: http://www.hprinzler.de
[ Flowform Plan ] [ Flowform Sketches ] [ Flowform Gallery ] [ History and Progress ] [ Members ]

International Flowform Workshop

I was asked several times for information about large flowforms or flowforms with a molar shape. Therefore I made some drawings and calculations for a preliminary plan and started an International Flowform Workshop in the newsgroup rec.kites for all builders interested in this kite. Everyone who like can build this kite (not for commercial use) and share his experiences and thoughts about the project.

History and Progress

April 07, 2000
Alberto Bonati has finished his molar flowform. On the beach he had made his maiden flight with great success. Photos of the kite he published on his web site.
Andy Beveridge started his work on the flowform, after recovering from his buggy accident last year.

October 04, 1999
The kite made by Sebastian Laiblin had his maiden flight and I got first photos.

September 09, 1999
Until now I had no more information about progress of other builders. But there are some new builders, who started to build this kite and some more are interested in building a flowform.
My work on the flowform is finished. Last weekend on medium wind it flew again with a lot pull.

June 09, 1999
Now the problem with the folds on upper leading edge is solved. With reducing the height of the inlet to about 78 percent of the maximum profile height there are no folds and the starting of the kite is much easier. Now, I have only to do the finework on the change, then my flowform project is done.
To reduce the height of the inlet on the ready made flowform I marked the point with 78 percent of maximum profile height on the front edge of each profile. From this point I draw a line to the height of the lower leading edge. This line I sewed to the upper surface as the new upper profile line. The modification on the profile is shown in the sketch. The plan is modified for the final version. There are the new profile datas related to the lower leading edge.

May 27, 1999
During a short holiday trip to the netherlands I got the chance for the maiden flight. It was very difficult to start the kite, but after several trials the kite flews in a height of about 8 metres. The wind came from sea with about 3 bft. The beach was small and the height of the beach increases in steps. The flowform flies stable with and shows no affects of turbolences depending on low height flying.
Problems are the difficults on starting the kite and the folds near the leading edges of the profiles and the top surface. Next I will try to reduce the height of the inlet to solve this problem and to get a better start of the kite. The first photos of my newest flowform are published.

May 03, 1999
I got it. All sewing is done. Now I am waiting for the maiden flight. Last weekend there was zero wind, if I got time for flying. Not the best conditions. For my work on this flowform I spent 7 hours for developement, 6 hours for design and work preparation, 28 hours for cutting the pieces, 29.5 hours for all the sewing and 1.5 hours for bridling the flowform.

April 16, 1999
Large steps on progress with my kite. All pieces are cutted and prepared for sewing. I have started with sewing the pieces together. The bottom side with profiles and keels is finished. With the top side I have started. After that I have to close the trailing edge. I think to need about 6 to 10 hours until finishing the kite.
No information about progress from other builders.

March 26, 1999
The air flow holes on all pieces for bottom and top surface are done. I used wrong sizes on som pieces. So, I changed all holes to the maximum size and I think, that will work, too.
Alberto Bonati waits for information about the success before he will start. No more information from other builders at the moment.

February 23, 1999
Now I have updated the verification of both airfoil datas once more, because the upper leading edge was too far from position of lower leading edge. My own kite building goes on slowly. I spend more time for my chidren at the moment. The pieces of all keels and the pieces for profiles P1 are sewed together. Now I have to start with the fine work on these pieces.
We have a new member for the International Workshop. Xuan Bui from France wants to build this kite, too.
Roger from England has some problems to continue his progress on kite building.

February 08, 1999
In January I have updated my program for airfoil calculation to version 2.00. A new feature is to calculate parts of an airfoil with adding an offset to the X-position. The verification of both airfoil datas shows only small differences on all profiles. Only the height of profile p2 starts to decrease later as the height from profile p2 calculated by program. But I think the flying results will be nearly the same.
I cutted all pieces for the keels. Next I will cut the profiles p1, which will be made by four pieces each.

December 21, 1998
I think, Roger is the one with the most progress. Three weeks ago he had cut the profiles p1 and wanted to start with the profiles p2.
My one work is not started yet. I still hope to start after chrismas or in january. I found a room, where I can cut the large pieces.
Meanwhile Alberto did the translation of the flowform comparison in italian. I think, he didn't start with this flowform until now.

November 27, 1998
From Alberto I got a new sketch with the correct length of the bridle lines.

November 24, 1998
I added a sketch about dividing the keels in pieces to lead the drag better through the keels.
I changed the length of the bridle lines to the right values. I don't know how I calculated the wrong ones.

November 17, 1998
Alberto Bonati made some sketches of the flowform data table and found an error on the top surface of the profile P2.

November 11, 1998
The drawings and calculations are made and a simple plan in ASCII-graphics is created. Roger Parry and Alberto Bonati (Italy) are interested in the new flowform plan. The idea of an International Flowform Workshop with information transfer via internet is born.

November 04, 1998
Roger Parry (United Kingdom) asked me about enlargements of my flowform no 3. I answered, for a larger flowform the height of the profile should be smaller and the amount of keels should be increased. The idea for a larger flowform with a molar shape is born once more.

Members of the Workshop

Harald Prinzler (Germany)
I did the developement of this flowform after comparison of information about flowforms I got. If I got the time from my 2 children I will build this kite in a large size. If the project fails, I can make smaller kites out of the fabric ;-)

Roger Parry (United Kingdom)
He built the flowform no. 3 and want to build a larger one. That is a goal for a workshop of the local kite club and so he is interested in information for larger flowforms.

Alberto Bonati (Italy)
He just finished the work on the Rowlands flowform. Now he thinks about a larger flowform no. 3 and is interested in the new flowform with the molar shape.

Xuan-Cuong BUI (France)
He built 2 flowforms no. 3 with a spanwidth of 1m in the year 1998 with great success. Now he wants to build this kite in small size in the next days.

Sebastian Laiblin (Germany)
He started to build this kite in a size of 2m spanwidth and 2.5m profile base line. He want to use this kite for KAP.

Andy Beveridge(United Kingdom)
He wants to build this flowform in a size of 2m spanwidth and 2.5m profile base line.