What components are a major source of galvanic corrosion on aircraft?

Galvanic corrosion occurs when two dissimilar metals are in contact within a conductive environment, such as moisture in the air. In aircraft systems, bonding and grounding straps are critical components that serve to connect different metallic parts to maintain electrical continuity and reduce electrical resistance. Since these straps often connect various metals, such as aluminum to copper, they create an environment conducive to galvanic corrosion.

The process involves an electrochemical reaction where the more anodic metal (the one that oxidizes) corrodes more rapidly when in contact with a more cathodic metal. The bonding and grounding straps, therefore, can create a scenario where differing metal types are in close contact, leading to galvanic corrosion if not properly protected or insulated.

In contrast, wires and cables generally have insulation that prevents direct metal-to-metal contact and established pathways can help avoid galvanic issues. While landing gears and control surfaces may also experience corrosion from other sources, the specific association of dissimilar metals in bonding and grounding makes these components a major source of galvanic corrosion on aircraft.