Definition
A friction clutch in which a cone-shaped male member is forced into a matching cone-shaped female seat. When the two cones are pressed together, friction between their angled surfaces locks them so they rotate as one unit; when separated, the driving and driven shafts turn independently.
Plain English
A coupling that connects two rotating shafts by wedging a cone into a matching cone-shaped cup. Push them together and they spin as one. Pull them apart and one can turn while the other stays still.
Context Anchor
Seen in aircraft engine, starter, or accessory-drive descriptions where one rotating part must be connected to another.
Derivation
From the Latin 'clutch' sense of grasping, paired with 'cone' from the Latin 'conus' meaning a tapered shape. The name describes exactly what it is: a clutch that grasps using cone-shaped surfaces.
Why Pilots Care
Cone clutches engage smoothly, which protects the engine and driven components from sudden shock loads during starting or power transfer. Knowing the principle helps when reading system descriptions or troubleshooting starter and accessory engagement issues.
Analogy
Think of pushing a paper cup firmly into a slightly larger paper cup. Once seated, twisting one turns the other. Lift it out, and they spin independently.
Intuition Check
Do not think of a cone clutch as a cockpit clutch pedal. In this context, it is an internal mechanical part that grips by using matching cone-shaped surfaces.
Example Sentence 1
The starter engages the engine through a cone clutch that gradually transfers torque as the cones seat together.
Example Sentence 2
Wear on the cone clutch surfaces can cause slipping and loss of power to the accessory drive.