Sport Pilot for Helicopter - Simplified Flight Controls › VI. Performance Maneuvers › Task B. Straight-In Autorotation in a Single-Engine Helicopter-Simplified Flight Controls

SH.VI.B.K5

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Effect of varying bank angles, airspeeds, and rotor rpm.

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Get a short, cited explanation of this element written from the FAA handbooks: the core idea, the numbers that matter, common test traps, and a quick self-check.

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Helicopter Flying Handbook p. 11-2
Chapter 11: Helicopter Emergencies and Hazards › Autorotation
Following this general procedure of fitting airspeed and rotor rpm to existing conditions, a pilot can achieve approximately the same glide angle in any set of circumstances, and thereby estimate the touchdown point accurately. Figure 11-1. During an autorotation ... upward flow of relative wind permits the main rotor blades to rotate at their normal speed. In effect, the blades are “gliding” in their rotational plane. It is important that pilots experience autorotations from various airspeeds. This provides better understanding…
Helicopter Flying Handbook p. 4-11
Chapter 4: Helicopter Components, Sections, and Systems › Transmission System › Dual Tachometers
Main Rotor Transmission The primary purpose of the main rotor transmission is to reduce engine output rpm to optimum rotor rpm. This reduction is different for the various helicopters. As an example, suppose the engine rpm of a specific helicopter ... rotor speed of 450 rpm would require a 6:1 reduction. A 9:1 reduction would mean the rotor would turn at 300 rpm. Dual Tachometers Most helicopters use a dual-needle tachometer or a vertical scale instrument to show…
Helicopter Flying Handbook p. 11-16
Chapter 11: Helicopter Emergencies and Hazards › Low Rotor RPM and Rotor Stall
Other causes of a power-on low rotor rpm condition include the pilot rolling the throttle the wrong way in helicopters not equipped with a governor or a governor failure in helicopters so equipped. As the rpm decreases, the amount ... horsepower the engine can produce also decreases. Engine horsepower is directly proportional to its rpm, so a 10 percent loss in rpm due to overpitching, or one of the other scenarios above, will result in a 10 percent loss…
Helicopter Flying Handbook p. 11-3
Chapter 11: Helicopter Emergencies and Hazards › Autorotation › RPM Control
RPM Control Rotor rpm in low inertia rotor systems has been studied in simulator flight evaluations which indicate that the simultaneous application of aft cyclic, down collective, and alignment with the relative wind (trim) at a wide range of airspeeds ... including cruise airspeeds, is critical for all operations during the entry of an autorotation. The applicable Rotorcraft Flight Manual (RFM) should be consulted to determine the appropriate procedure(s) for safely entering an autorotation. This is vitally important since…