Miles McCallum wrote:
> Fred F. wrote:
> > How true. The effect of surface roughness was studied long ago, and
> > up to a point (incl. fine sandpaper) it's insignificant. You can
> > sprinkle talcum powder on a waxed wing, go flying, and wipe away
> > residue on return.
>
> But.... will you be flying as fast? see the CAFE website for an
> investigation of the effects of a wax job on a mooney.
Miles, I did read that report, but then referenced it to Dr. Hoerner's
book at page 5-3, and then was amused. It's curious they chose a
Mooney, as drag of even micron-size imperfections rises sharply at
around 200MPH, thence going roughly flat. The effect is only on the
leading edges of things, he says, and they were careful to note that
the pre-wax surface was insect-free. However, they state the paint
was oxidized, suggesting the leading edges were even worse (abrasion).
Filling a rough leading-edge surface like that with wax will help, to
be soon canceled by the bugs.
Regards,
Fred F., A063
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