Definition
Visible damage to the outer covering (skin) of an aircraft, including dents, cracks, scratches, punctures, loose or missing rivets, wrinkled or buckled metal, corrosion, or delamination of composite surfaces. Such damage is identified during preflight inspection and may indicate underlying structural problems that affect airworthiness.
Plain English
Damage to the outside surface of the airplane — things like dents, cracks, missing rivets, or wrinkled metal — that you look for during preflight and that may mean the airplane isn't safe to fly until checked by a mechanic.
Context Anchor
Seen during the preflight walk-around when checking the wings, fuselage, tail, and control surfaces for dents, cracks, holes, or other surface problems.
Derivation
Skin' is used in aviation to mean the thin outer covering of an aircraft, much like skin on a body. The term reflects that this surface is the aircraft's outermost layer — the first thing you see and the first thing to show signs of trouble.
Why Pilots Care
Unaddressed skin damage can create stress points, reduce lift, or signal deeper structural issues that affect airworthiness.
Intuition Check
“Skin” here means the airplane’s outer covering, not human skin. “Damage” does not mean every small stain or normal wear mark is unsafe; it means a mark, break, or change that could affect safety or needs maintenance judgment.
Example Sentence 1
During the preflight walk-around, the pilot noticed skin damage near the wing root and grounded the aircraft until a mechanic could inspect it.
Example Sentence 2
Hail left visible skin damage on the horizontal stabilizer, requiring a detailed inspection before the next flight.