Blade interactions with support structure wakes caused excitation of the first bending mode, which in turn caused a fatigue failure. The re-engineering process first required careful CAD modeling of the system to accurately capture all of the important geometry. Next, FEA and CFD analyses were performed for the current blades and surrounding geometry, both upstream and downstream. Once the analysis was completed, the blades were redesigned to increase the natural frequency. One of the challenges, however, was that the hub could not be changed, so blade mass needed to remain close to the original to limit centrifugal force increases. CFD analysis of the full rotating 16-blade fan with support structure showed a number of potential excitation frequencies. The new blade design needed to avoid any bending or torsion mode interactions with these aerodynamic excitation forces.