When repairing an all-metal aircraft, what should be the criteria for selecting replacement metals?

Selecting replacement metals for an all-metal aircraft is crucial to ensure the integrity, performance, and safety of the aircraft. The correct choice emphasizes the importance of using metals that match the original in both type and thickness.

Using metals of the same type ensures compatibility with the existing airframe materials, which is vital considering factors like thermal expansion rates, stress tolerances, and corrosion resistance. For example, if the original aircraft structure is made of aluminum alloy, introducing a different alloy or material could lead to galvanic corrosion at the junction points or unequal stress distribution.

Matching the thickness is also important to maintain the structural integrity of the aircraft. Different thicknesses can alter the load-carrying capacity and aerodynamic properties of the component. If a replacement is too thick, it may add unnecessary weight, or if it is too thin, it may not provide adequate strength, risking structural failure during operation.

Overall, adhering to the criteria of using the same type and thickness of metals aligns with best practices in aircraft maintenance and repair, ensuring safety and compliance with regulations.