# Actually a Serious Question (Regarding Surface Drag)

My daughter and I are at a loss for what to do for a good but relatively
inexpensive science fair project; an idea that would have required getting a
wing segment to rise in a wind tunnel didn't work out, which makes the rest of
that experiment impossible. We're now looking at doing something with a rubber
chicken (we have one lying around the house, and can get another). The rubber
chicken has a bumpy skin. If we get another chicken, and smear something all
over the surface of one chicken until its surface is smooth, but leave the
surface of the other chicken alone, we can stick a rocket up each chicken's
bottom and launch them, comparing altitudes to estimate the effect of surface
drag. We would need to add the equivalent amount of weight to the other
chicken, of course, but we'd do that internally. My question is, does anyone
have any thoughts about what to smear it with? I'm leaning toward epoxy (since
it would give the smoothed chicken a lot of rigidity, we'd need to smear the
other chicken internally so it wouldn't flop around in the air, which the
smoothed chicken won't be doing), but I'd be open to other suggestions.
How about getting two Quest Flat Cats, and doing them, one without airfoil wings, the other with and time their flights?
Post this to Uk.tech.rocketry, and ask Mike Roberts for assistance - he's the HPR chickewnmeister in the UK.
G.
This question comes up often enough someone (preferably a related vendor) really should do a web page on it.
Why not make 2 identical rockets with sandpaper epoxied to the body? One with the sandpaper facing in, one facing out. That way they'd be the same weight, but with different surface roughness coefficients.
Unless, of course, you'd prefer to stick your rocket up a chicken's bottom...? (you might want to check with the BATF on that one)

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