Abstract: A simplified layup mandrel with no contour or twist is utilized by the method of this invention for forming the spar member of an aerodynamic rotor blade. A fiber glass tape is wrapped (laid-up) to a desired thickness onto the simplified mandrel to form a strap as the initial step. Because of the simple design of the mandrel, the laid-up strap when removed from the mandrel has a basic U-shaped configuration with straight extending legs having substantially parallel vertically oriented faces. This strap is then placed on a forming mandrel and contoured to the desired shape either by hand or by coining in a forming die. The contoured strap is then utilized in any of the various subassemblies or final assembly of the composite aerodynamic rotor blade.