Plain English Meaning
A framework of beams or tubes joined together — usually in triangle shapes — that gives an aircraft its shape and strength. Older airplanes were built around a truss skeleton, often covered with fabric or thin metal.
Full Definition
A rigid framework of structural members — typically arranged in triangular patterns — used to support loads across a span. In aircraft, a truss forms the internal skeleton of the fuselage or wing, with longitudinal members (longerons) and cross members joined to resist bending and twisting forces.
Context Anchor
Seen in aircraft construction and airframe structure discussions, especially when learning about tube-and-fabric fuselages or internal support frames.
Derivation
From Old French 'trousse,' meaning a bundle or collection of things tied together. The engineering sense came from the idea of bundling structural members so they support each other — exactly what a truss does in an aircraft frame.
Why Pilots Care
Knowing whether an aircraft has a truss-type structure helps pilots understand inspection points, damage tolerance, and why certain repairs require specialized knowledge — particularly on tube-and-fabric aircraft still common in the training and backcountry fleets.
Analogy
A simple bridge made from triangles is a good picture of a truss. The triangles keep the frame from folding or twisting easily.
Intuition Check
Do not think of a truss as just any support or bracket. In aircraft structure, a truss is a connected framework designed to spread forces through several members.
Example Sentence 1
The Piper Cub uses a welded steel-tube truss fuselage covered in fabric.
Example Sentence 2
Engineers chose a truss design for the wing because it provided the needed rigidity at low weight.