The aviation equivalent of the annoying Harley rider who guns the engine at a traffic light is the pilot behind a constant-speed propeller who keeps cycling the prop beyond what's necessary during runup. Cycling the prop before takeoff does have a purpose, though. It verifies the system is operating correctly and:


Circulates hydraulic fluid through the propeller governor


Maintains proper fuel pressure


Circulates fresh, warm oil through the propeller governor


Announces that you also own a Harley

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