/By way of comparison, my Mk I set of wheel fairings were very similar,
except with a 2.5:1 L:D. The speed increase was identical (as best I could
measure), the 'poorer' L:D being offset by the lower surface area. All in
accordance with the theory for bodies-of-revolution as described by NACA
following experiments on buoyant 'dolphins'.
But a lot of work making moulds etc just to get to that point!
Duncan McF
/Duncan
the two guys I know with a successful track record are Klaus Savier and Gary
Hertzler.
Both are winners, Klaus at Reno and others Gary a CAFE winner. Have a
look at Klaus' wheel pant design, its optimised to get good pressure recovery
which is the key to low drag. The shape is usually referred to as "Hershy Kiss"
because of the reflexed trailing edge,perhaps? Klaus will tell you that the
TE must be closed as Fred remarked.
Both of these guys spent a lot of time streamlining things inside the
cowling,even
to the extent of making a streamlined sump for their engines, O-200 and O-235
Gear leg fairings; the most important thing is to be in line with the airflow,
and that isn't easy. This is what all the top EZ people say.
Make foam fairings in sections a few inches long, attach with fast cure micro,
then fly at cruise speed till it sets? Might work. It would be very interesting
to see what twist evolves. Perhaps safer to tie on wool tufts up the leg, go
fly and photograph.
Graham
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