What is the maximum allowable depth for nicks in metal tubing that can be repaired?

The maximum allowable depth for nicks in metal tubing that can be repaired is 10% of the wall thickness. This guideline is set to ensure the structural integrity of the tubing while acknowledging that minor imperfections can occur without significantly compromising safety. Allowing for nicks up to this limit helps to prevent potential failures due to excessive weakness while providing a clear standard for maintenance and repair.

If nicks exceed this percentage, the tubing could be at risk of fatigue or failure under load, particularly in high-stress applications. Therefore, staying within the 10% threshold is not only a recommended practice but also a necessary precaution to maintain the overall strength and reliability of the metal structure. This standard reflects a balance between practicality in repairs and maintaining the necessary safety margins in aeronautical engineering.