When modeling fins in software such as RasAero or OpenRocket, what's the
best way to handle the fin bracket? Does it contribute as much
aerodynamically as the fin does? For example, I have fin brackets that
are the same length as the fins but are 1 inch tall. The fins
themselves have a 5 inch span with 1 inch gripped by the brackets. It
seems from a flutter standpoint that the span is only the 4 inches that
are protruding from the bracket but from an aero standpoint, the fin
span is 5 inches. Is this correct? Or is there some diminished
effectiveness of the fin since part of it is gripped by a much wider
bracket? The fins are 0.090 thick and the bracket width where it grips
the fin is about 0.35 inches. Body OD is 6 inches.
I'm about to trim the fins down to make them smaller but I don't want to
cut off too much. Here is a "before" picture with larger fins and
longer brackets:
http://www.watzlavick.com/robert/rocket/rocket1/photos/dsc_8310m.jpg
-Bob
