Patent ID: 9714579
Date: 2017-07-25
CPC Classifications: B64C,F01D

Claim:
1. An airfoil blade comprising: a root end; a tip end; and a body extending between the root end and the tip end with a pitch axis extending from the root end to the tip end, wherein the root end defines a chordwise axis extending perpendicular to the pitch axis and includes a first fastener hole and a second fastener hole aligned along the chordwise axis, the first and second fastener holes extending through the root end of the airfoil blade from a top surface of the root end of the airfoil blade to a bottom surface of the root end of the airfoil blade, the first and second fastener holes being configured to receive first and second fasteners, respectively, to couple the root end to a control cuff and a flexbeam head, the first fastener hole having a first diameter and being spaced a first distance from the pitch axis, the second fastener hole having a second diameter and being spaced a second distance from the pitch axis, the first distance being different from the second distance, the first diameter being larger than the second diameter, wherein the first fastener hole is between the leading edge and second fastener hole.