What role do adhesives play in aircraft metal structural repair?

Adhesives play a crucial role in aircraft metal structural repair by bonding materials together, providing a strong and durable connection that is essential for maintaining the structural integrity of the aircraft. The use of adhesives allows for the distribution of stresses over a larger area, which can enhance the overall strength of the repair compared to traditional mechanical fastening methods.

By bonding materials, adhesives can help to seal against environmental factors such as moisture and corrosion, further protecting the structure of the aircraft. Additionally, they allow for repairs in areas where traditional mechanical fasteners may not be feasible due to space constraints or the need to maintain a smooth aerodynamic profile.

In contrast to the other options, adhesives are not intended to serve solely as temporary fasteners or be used only for insulation purposes. While they can sometimes be part of a system that includes mechanical fasteners, they are not meant to replace those fasteners entirely in structural applications. Their primary function is to permanently bond materials, making them indispensable in aircraft repairs where strength, durability, and weight considerations are critical.