X-Mozilla-Keys:                                                                                 
Al Gietzen wrote:

Jeff;

Here's a picture of my nominee for the title "lowest propulsive

efficiency".

At least 50% of the prop disk is blanked.  13 years and three prototypes

and

this is the best they could come up with.  On a positive note: tests were
conducted to evaluate the effect of the spinner.  The result: It looks

better

with it on ;-)

Not that it's important to us here, but it is not as bad as it looks.  A
little over a third of the diameter is blanked which is only about 12-15% of
the area (pi*D^2, and all that); and we know that the inner portion of the
blades produce little thrust anyway.  The thing really has pretty impressive
performance.

Al Gietzen

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