Main rotor speed and pitch limits.

CFR · 2024-01-01 · US · Title 14

(a) (1) With power on, provides adequate margin to accommodate the variations in rotor speed occurring in any appropriate maneuver, and is consistent with the kind of governor or synchronizer used; and (2) With power off, allows each appropriate autorotative maneuver to be performed throughout the ranges of airspeed and weight for which certification is requested. (b) (1) Appropriate setting of the main rotor high pitch stop; (2) Inherent rotorcraft characteristics that make unsafe low main rotor speeds unlikely; or (3) Adequate means to warn the pilot of unsafe main rotor speeds. (c) (1) The normal main rotor low pitch limit provides sufficient rotor speed, in any autorotative condition, under the most critical combinations of weight and airspeed; and (2) It is possible to prevent overspeeding of the rotor without exceptional piloting skill. (d) (e) (1) The warning must be furnished to the pilot in all flight conditions, including power-on and power-off flight, when the speed of a main rotor approaches a value that can jeopardize safe flight. (2) The warning may be furnished either through the inherent aerodynamic qualities of the helicopter or by a device. (3) The warning must be clear and distinct under all conditions, and must be clearly distinguishable from all other warnings. A visual device that requires the attention of the crew within the cockpit is not acceptable by itself. (4) If a warning device is used, the device must automatically deactivate and reset when the

official document · source cfr-2024 · id 14:§ 29.33