On Wed, 26 Mar 2008 06:24:01 -0700 (PDT), wrote:

Hello,

I need some information about Clark Y profiles. I found a lot of
information like coordinates, but I really need design parameters.
Like design lift coefficient, nose radius and trailing edge radius.
I would really appreciate your help!

Bart

the clark Y aerofoil is 17% thick and has it's ordinates set out from
the bottom surface.

the NACA 4417 aerofoil is the clark Y with the ordinates set out from
the chord line.
Theory of Wing Sections, Abbott and Von Doenhoff has the info on the
4418 (1% thicker) on page 492 and 493. that should be close enough if
you compare the 4415 on the previous pages.

if you search the naca.larc.nasa.gov website search engine there are
naca technical reports on the aerodynamics of the clark Y.

the shape was an educated guess based on a number of previous good
aerofoils. justinius clark had a reasonably good eye for these things.

Stealth Pilot