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A variable pitch fan for a helicopter equipped with a NOTARTMmechanical antitorque directional control system comprises a plurality of blade assemblies. Each blade assembly includes a blade portion, which is molded from a blended material which includes fiber reinforced polypropylene. A key to the i

A variable pitch fan for a helicopter equipped with a NOTARTMmechanical antitorque directional control system comprises a plurality of blade assemblies. Each blade assembly includes a blade portion, which is molded from a blended material which includes fiber reinforced polypropylene. A key to the invention is the use of long fibers, having a length of at least approximately one-half inch, for reinforcement, the long fibers providing for about twice the pull-out strength of short or chopped fibers. Another key aspect of the invention is the use of a blowing agent in the blended material, which serves to reduce weight and warpage by creating a foamed structure having a variable density, the structure retaining considerable strength because of the fiber reinforcement. The blade portion is molded about a spar which has holes therethrough, the holes providing a mechanical interlock between the blade and the spar.

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An injection molded rotor blade assembly, comprising: a blade portion molded from a blended material which includes a thermoplastic polymer reinforced with long fibers and a blowing agent, wherein said blade portion comprises an interior portion having a generally open-celled structure, said interio

An injection molded rotor blade assembly, comprising: a blade portion molded from a blended material which includes a thermoplastic polymer reinforced with long fibers and a blowing agent, wherein said blade portion comprises an interior portion having a generally open-celled structure, said interior portion being enclosed by an exterior skin formed from the blended material, which is substantially solid; and a spar to which said blade portion is attached.