SIFT Army Aviation Information Practice Test 2025 – All-in-One Study Guide for Exam Success!

When the collective pitch controller is increased, the rotor blades pitch angle is increased, leading to more lift being generated. This increase in lift causes a greater load on the rotor system, which results in the engine needing to compensate for the additional load to maintain rotor speed.

As the pitch of the blades increases, unless there is a corresponding increase in power from the engine, the RPM of the rotor will decrease due to the increased aerodynamic drag. The collective control is primarily used to alter the lift, and while the engine attempts to maintain RPM, the increase in blade pitch typically results in a decrease in rotor speed if power is not adjusted accordingly.

This phenomenon is critical for pilots to understand, as managing RPM is essential for safe flight operations. Understanding the relationship between the collective pitch and rotor RPM is fundamental in aviation, particularly in helicopter dynamics.