Definition
A characteristic of a variable resistor (potentiometer) or rheostat in which the resistance changes in direct proportion to the rotation or movement of the control shaft. Equal increments of shaft movement produce equal increments of resistance change across the full range of travel.
Plain English
A control knob whose resistance goes up evenly as you turn it. Half a turn gives you half the resistance, three-quarters of a turn gives you three-quarters of the resistance, and so on.
Context Anchor
Seen in aircraft design, aircraft drawings, and maintenance descriptions of wing shape or other tapered parts.
Derivation
‘Linear’ comes from the Latin linearis, meaning ‘of or belonging to a line’ — a straight-line relationship. ‘Taper’ here is an electrical term describing how resistance is distributed along the resistive element. Together they describe a resistor whose values change along a straight line as the shaft turns.
Why Pilots Care
Linear taper produces predictable lift distribution and stall behavior that affects handling and performance.
Analogy
Think of a board cut so one side forms a straight diagonal line. Each inch along the board, it gets the same amount narrower.
Intuition Check
Linear taper does not mean just any narrowing. It means the narrowing happens evenly, at a constant rate, in a straight-line shape.
Example Sentence 1
The panel light dimmer uses a linear taper, so the brightness adjusts smoothly and evenly across the full sweep of the knob.
Example Sentence 2
Mechanics check the propeller for correct linear taper during overhaul.