May transverse cracks in a metal propeller blade be repaired?

May transverse cracks in a metal propeller blade be repaired?

• A. Yes, if size is small
• B. Only under FAA approval
• C. Only if the blade is aluminum
• D. No, any transverse crack is a reason for rejecting the blade

Answer: (D)

Transverse cracks in a metal propeller blade signal fatigue damage that directly affects the blade’s ability to carry load safely. For a safety-critical part like a propeller blade, a crack that runs across the blade’s cross-section means the structural integrity can't be guaranteed, even if the crack seems small. Because of the fatigue risk and the difficulty in ensuring any crack-related damage won’t grow under service loads, repairs are not allowed for this type of flaw. The blade must be rejected and replaced to restore airworthiness. This rule applies regardless of the material (aluminum or other metals) or the crack’s apparent size.

Transverse cracks in a metal propeller blade signal fatigue damage that directly affects the blade’s ability to carry load safely. For a safety-critical part like a propeller blade, a crack that runs across the blade’s cross-section means the structural integrity can't be guaranteed, even if the crack seems small.

Because of the fatigue risk and the difficulty in ensuring any crack-related damage won’t grow under service loads, repairs are not allowed for this type of flaw. The blade must be rejected and replaced to restore airworthiness. This rule applies regardless of the material (aluminum or other metals) or the crack’s apparent size.