Definition
A composite construction made by bonding two thin, stiff outer face sheets to a thicker, lightweight core material. The faces carry tension and compression loads, while the core separates the faces and resists shear, producing a panel that is far stiffer and lighter than a solid sheet of equivalent strength.
Plain English
A panel built like a sandwich: two strong outer skins glued to a light filling in the middle. The middle keeps the skins apart, and that arrangement makes the whole panel very stiff for its weight.
Context Anchor
Seen in aircraft maintenance when working with composite panels, control surfaces, cabin floors, and other lightweight airframe parts.
Derivation
Named directly after the food sandwich — two outer layers with a filling in between. The visual is the explanation: when engineers saw the layered construction, the everyday word stuck.
Why Pilots Care
Sandwich panels are common in modern airframes because they save weight while staying rigid, but they are also vulnerable to hidden damage. Water ingress, delamination, or a crushed core can drastically weaken a panel without obvious surface signs, which is why inspections and proper repair procedures matter.
Intuition Check
“Sandwich” does not mean food or a loose stack of parts here. It means a bonded aircraft structure with two outer layers and a lightweight middle layer working together as one panel.
Example Sentence 1
The cabin floor panels are made from sandwich material with aluminum face sheets bonded to a honeycomb core.
Example Sentence 2
Inspectors checked the sandwich material in the tail for any separation between the layers.