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On an airplane with a constant-speed propeller, which control sets manifold pressure and which sets RPM?
Choices
The throttle sets RPM; the propeller control sets manifold pressure
It is the reverse — the throttle sets manifold pressure, not RPM.
✓ The throttle sets manifold pressure; the propeller control sets RPMcorrect
The throttle controls manifold pressure and the propeller control commands the governor to hold the selected RPM.
The mixture sets manifold pressure; the throttle sets RPM
The mixture controls the fuel/air ratio, not manifold pressure.
Both are set by the throttle alone
A constant-speed system uses two separate controls for power and RPM.
Why
With a constant-speed propeller the throttle sets manifold pressure and the propeller control sets RPM; increase power by advancing the propeller control (RPM) first then the throttle, and reduce power in the reverse order.
FAA source: PHAK Ch. 7browse the reference library →
Original study question written for this course — representative of FAA knowledge-test topics, not an actual current FAA exam question.