Bill Freeman wrote:

Paul,

IMHO, another serious problem with the Warp Drive
blades for high speed and esp high RPM is the thickness
issue.  IIRC, they look to be about 15% thickness,
which is OK at low tip speeds but the drag increased
*very* seriously at higher Mach numbers.   I'll get
some example plots of coeff of drag vs coeff of lift
for a NACA 16 series 6% or 8% prop airfoil at .8 Mach
vs say a NACA convential wing airfoil around 15%
thickness under the same conditions.  The drag coeff
is MUCH higher, which produces much less thrust
for the same HP.

Bill

 
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