Definition
A clutch mechanism in a turbocharger or supercharger drive system that uses pressurized engine oil to engage and disengage drive components, allowing the unit to be brought online or taken offline smoothly as required by the induction system.
Plain English
A connector inside the engine that uses oil pressure to hook up or release the spinning parts that drive a turbocharger or supercharger, so it can be switched in or out without a sudden jolt.
Context Anchor
Seen in discussions of engine-driven superchargers and older induction systems that can change supercharger drive settings.
Derivation
A clutch is a device that connects and disconnects two rotating parts. 'Oil-operated' simply means engine oil pressure is what makes it engage or release, rather than a cable, spring, or electric actuator.
Why Pilots Care
Allows selection of low or high blower ratios for proper manifold pressure at varying altitudes without risking mechanical damage to the drive train.
Analogy
It is like a car clutch in the basic sense: it connects or separates power flow. The difference is that this aircraft part uses oil pressure to do the connecting instead of a foot pedal.
Intuition Check
Do not read “oil-operated” as meaning the clutch is lubricated by oil only. Here, oil pressure is what actually moves or controls the clutch.
Example Sentence 1
The supercharger uses an oil-operated clutch to engage the high-speed drive once the engine reaches operating oil pressure.
Example Sentence 2
During climb the oil-operated clutch automatically shifted the supercharger to maintain manifold pressure.