Patent ID: 8795567

Claim:
A method of fabricating a fiber reinforced composite stiffener that is substantially wrinkle-free, the method comprising: using a tool, the tool having a sidewall, the sidewall including a first portion along a first length that is less than a total length of the sidewall, the sidewall further including a second portion along a second length that is less than the total length and a third portion along a third length that is less than the total length, the first portion being between the second portion and the third portion, the first portion having an out-of-plane curvature and an in-plane curvature, the second portion having a second curvature different than the in-plane curvature and the out-of-plane curvature, the third portion having the second curvature, the tool further having a bottom tool face along the sidewall and connected to the sidewall at an angle, the bottom tool face also having the out-of-plane curvature along the first length, and the bottom tool face further having the second curvature along the second length and the third length; using includes forming a lay-up over the tool by laying up a plurality of fiber reinforced composite plies over the tool, including simultaneously conforming the plurality of fiber reinforced composite plies to the first length and the second length along both the sidewall and the bottom tool face; and compacting the lay-up.