Definition
A condition in which the bonded layers of a laminated material have separated from one another, leaving voids or weakened areas between the plies. Common in composite structures, plywood, fiberglass, and bonded honeycomb panels used in aircraft construction.
Plain English
The layers of a layered material have come unstuck from each other.
Context Anchor
Seen during aircraft inspections, especially on wood, fiberglass, and composite parts such as fairings, control surfaces, propellers, or structural panels.
Derivation
From Latin 'lamina' meaning a thin plate or layer, with the prefix 'de-' meaning away or apart. Literally 'layers come apart' — which is exactly what has happened.
Why Pilots Care
Delamination reduces the strength and stiffness of the structure and can lead to sudden failure under flight loads.
Analogy
It is like plywood starting to peel apart. The board may still look like one piece at a glance, but once the layers separate, it is not as strong as it was designed to be.
Intuition Check
Do not assume delaminated means only a surface scratch or paint problem. It means layers of the material have separated, which can affect strength.
Example Sentence 1
The mechanic found a delaminated section near the leading edge of the composite wing skin and grounded the aircraft for repair.
Example Sentence 2
Hail damage left the wing leading edge delaminated and grounded the aircraft until repaired.