Definition
The gradual chemical or electrochemical deterioration of a metal caused by reaction with its environment, typically moisture, oxygen, salt, or other contaminants. On aircraft, corrosion weakens metal structures and components by eating into the surface, producing pits, rust, white powder, or flaking, and can compromise structural integrity if not detected and treated.
Plain English
The slow eating-away of metal when it reacts with moisture, air, or chemicals. It shows up as rust, pitting, or powdery deposits and weakens the part it attacks.
Context Anchor
Seen during preflight inspection and maintenance checks of landing gear, wheel areas, brake parts, and exposed metal surfaces.
Derivation
From the Latin corrodere, meaning 'to gnaw away' (co- 'thoroughly' + rodere 'to gnaw'). The image fits — corrosion literally gnaws at metal over time.
Why Pilots Care
Unchecked corrosion weakens structural components like landing gear struts and can lead to failure during landing or taxi.
Grounding Statement
If moisture and dirt sit on metal long enough, the surface can start to break down even while the airplane is parked.
Intuition Check
Corrosion does not only mean reddish rust. In aviation, it can include many kinds of metal damage, including white, gray, green, or pitted areas, depending on the metal involved.
Example Sentence 1
During preflight, the pilot noticed white powdery corrosion forming around a landing gear bolt and wrote it up for maintenance.
Example Sentence 2
After the aircraft sat outside in the rain, the mechanic inspected the brake components for hidden corrosion inside the wheel wells.