Definition
A structural metal shape with a cross-section resembling a squared-off letter C, consisting of a flat web with two flanges projecting from the same side at right angles. Channel sections are used in aircraft structures where strength and stiffness are needed along one axis without the weight of a fully closed shape.
Plain English
A long piece of metal shaped like the letter C when you look at the end of it. It has a flat back with two short sides sticking out, used as a structural part in aircraft.
Context Anchor
Seen in aircraft structure, sheet-metal work, repair descriptions, and maintenance discussions about supports or stiffeners.
Derivation
The word 'channel' comes from the Latin 'canalis,' meaning a groove or pipe. The shape is named for its trough-like appearance — the open side forms a channel running along the length of the piece.
Why Pilots Care
If a maintenance report mentions a damaged channel section, the pilot should understand that it refers to a structural shape, not a radio channel or navigation route.
Analogy
Think of a piece of household guttering — flat on one side with two raised edges. A channel section is the same idea in aircraft-grade metal.
Intuition Check
Do not read “channel” here as a radio frequency or communication path. In this term, it means the U-shaped form of a structural piece.
Example Sentence 1
The mechanic fabricated a small channel section from aluminum sheet to reinforce the damaged stringer.
Example Sentence 2
Channel sections provide lightweight strength in the fuselage frame.