My recommendation for the Rowlands Flowform is a quarter of the width of the kite for the diameter of the inlet of the drogue. The ration of outlet to inlet I would say 0.25. The length of the drogue is your choice. I wonder, if a short one works better as a longer one. The distance between kite and drogue should be about 7 times of th depth of the kite.
Harald.
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http://www.kitebuilder.com/forums/viewtopic.php?p=73247
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http://members.aol.com/hprinzler/drogue.htm
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