Do I misunderstand?  A fixed pitch prop can be designed for one particular
condition, and therefore can be "better" (however you measure better) at that
one condition than even a very good variable pitch prop that is designed to
operate over a range.  The amount of twist would be a compromise on a
variable pitch when none of the characteristics would be compromised on a
fixed pitch.

Isn't the comparison of the variable pitch prop against a series of fixed
pitch props, each optimized for a particular speed?

Confused,
Rob Gaddy

Usually what is done with a constant speed prop is optimize the twist for
the cruise speed of the airplane it is designed to be installed on.
If you put a constant speed prop designed for a 182 on a cleaner airplane it
should be re-twisted for a higher cruise speed.

Paul Lamar
 
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