Definition
A propeller system that automatically adjusts blade pitch to maintain a pilot-selected RPM regardless of changes in airspeed, power, or aircraft attitude. The pilot sets the desired RPM with the propeller control, and a governor varies the blade angle to hold that RPM as flight conditions change.
Plain English
A propeller whose blades automatically twist to a steeper or flatter angle so that the engine keeps spinning at the same RPM the pilot has chosen, even when the airplane speeds up, slows down, climbs, or descends.
Context Anchor
In the Chandelle chapter, this term appears when discussing airplanes whose propeller and power controls may need to be managed during a climbing, turning maneuver.
Derivation
Constant-speed means the rotational speed (RPM) stays constant. The blades change pitch, but the engine speed does not.
Why Pilots Care
Maintains efficient engine operation and consistent thrust response throughout varying flight conditions.
Analogy
Like the gears on a bicycle adjusting automatically so your legs always pedal at the same comfortable cadence, whether you're going uphill or downhill.
Intuition Check
Constant-speed does not mean the airplane flies at a constant speed. It means the propeller system tries to hold the engine at the RPM the pilot selected.
Example Sentence 1
Before entering the chandelle, the pilot set the constant-speed propeller to climb RPM and advanced the throttle to climb power.
Example Sentence 2
After leveling off the pilot reduced power and the constant-speed propellers increased blade pitch to keep RPM from rising.