Definition
A composite construction made of two thin, stiff outer skins (face sheets) bonded to a thicker, lightweight core material such as foam or honeycomb. The combination produces a panel that is much stiffer and lighter than a solid panel of the same weight, but is vulnerable to damage if the core is crushed, soaked with water, or the bond between skin and core fails.
Plain English
A panel built like a sandwich: two thin, strong layers on the outside with a light filler in the middle. It's very light and stiff, but easy to damage if hit, soaked, or if the layers come unstuck.
Context Anchor
Seen in discussions of composite aircraft construction, especially wings, control surfaces, fairings, and other lightweight panels.
Derivation
Named after the food: two outer layers with something light in the middle. The name describes exactly how the panel is built.
Why Pilots Care
Delivers high strength-to-weight performance in airframe components but requires careful inspection to prevent moisture damage or core-to-skin separation.
Analogy
Think of a lightweight door with thin outer faces and a light middle inside. The outside surfaces give shape and strength, while the middle keeps them separated so the whole panel stays stiff without much weight.
Intuition Check
Do not read sandwich structure as a loose stack of parts. Here it means a bonded, layered aircraft construction with a core between two outer layers.
Example Sentence 1
The cabin floor panels use a sandwich structure with thin fiberglass skins over a honeycomb core to keep weight down.
Example Sentence 2
Technicians must seal the edges of any sandwich structure panel to stop water from reaching the core.