FAA Powerplant Written Practice Test

Where on an axial flow compressor blade is damage most likely repairable?

1. Root section

2. Middle section

3. Outboard section

4. Leading edge

The correct answer is: Outboard section

The outboard section of an axial flow compressor blade is often the most repairable area due to its design and functionality. This section, which is typically farther from the rotor hub than the middle and root sections, experiences different stress and loading conditions compared to the other areas of the blade. Damage in the outboard section is usually more superficial and amenable to repair techniques such as re-coating, reshaping, or even replacing smaller segments of the blade. Additionally, if the outboard section is damaged, it may not compromise the integrity of the entire blade as severely as damage in other regions, particularly the root section which is critical for mounting and load distribution. While repairs can be complex and costly, advancements in repair materials and techniques have made it feasible to restore the blade's function effectively in this region. The leading edge, while critical for aerodynamic performance and often the first area affected by erosion or impact damage, may require more extensive repairs or replacement, making it less ideal for repair options compared to the outboard section.