(Gee
Whiz... pg2)
You’ll see two options on the plans for the airfoil: undercambered
or flat-bottom. I built the undercambered wing and it was probably
more trouble than it was worth. The flat wing is much easier
to build, and should fly just as well.
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There are also two landing gear options: solid sheet, or built-up.
I built both and found that the built-up version was 1.5 grams
lighter, but it requires balsa-laminated outlines and extra
time to build. The choice is yours.
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The plans
show only 4 stringers for the top deck, but I added a fifth
right along the upper spine to avoid that “starved dog”
look. If you choose to do the same, you may want to rearrange
the other top stringers for a more even spacing arrangement.
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Flying
My prototype Gee Whiz came out to 10 grams without rubber or
nose weight - but it was tail heavy. I recommend using a plastic
prop (or hardwood if you carve one), as it will need the weight
up front. This model is still in the flight trimming stages,
but adjustments are being sorted out. It has a tendency to be
very sensitive to rudder and thrust adjustments. There also
seems to be a little spiral instability.
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Under power it tries to turn right (as per my plan) but it often
banks to the left while in the right turn. Adjusting the right
thrust reduces this but once it gets into line it wants to spiral
dive to the right. Thinking it was dutch roll I added some clear
mylar to the fin area - but things got worse. Okay, back to
square one!
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To combat these problems, I’d recommend increasing the
dihedral an extra 1/4 to 3/8 inch on each side. I’m
also thinking that a smaller prop will help, but have yet
to try it.
That's about it. If you've got questions or comments, feel
free to send me email here.
(Editor’s note: we’ll update this article with
any new info Bruce comes up with for trimming the Gee Whiz).
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