Sport Flight Instructor Helicopter - Simplified Flight Controls › II. Technical Subject Areas › Task D. Principles of Flight

FH.II.D.K5

Knowledge

Blade flapping and coning.

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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. 4-3
Chapter 4: Helicopter Components, Sections, and Systems › Main Rotor System › Semirigid Rotor System
blades cone upward, the center of pressures of the blades are almost in the same plane as the hub. Whatever stresses are remaining bend the blades for compliance. Helicopters with semirigid rotors are vulnerable to a condition known as mast ... bumping which can cause the rotor flap stops to shear the mast. The mechanical design of the semirigid rotor system dictates downward flapping of the blades must have some physical limit. Mast bumping is the result of excessive rotor flapping…
Helicopter Flying Handbook p. G-1
Glossary
Blade coning. An upward sweep of rotor blades as a result of lift and centrifugal force. Blade damper. A device attached to the drag hinge to restrain the fore and aft movement of the rotor blade. Blade feather or feathering ... rotation of the blade around the spanwise (pitch change) axis. Blade flap. The ability of the rotor blade to move in a vertical direction. Blades may flap independently or in unison. Blade grip. The part of the hub assembly…
Pilot's Handbook of Aeronautical Knowledge p. G-7
Glossary › Chart Supplement U.S. (formerly Airport/Facility
turbine engines, a condition in an axial-flow compressor in which one or more stages of rotor blades fail to pass air smoothly to the succeeding stages. A stall condition is caused by a pressure ratio that is incompatible with ... liquid. Condensation nuclei. Small particles of solid matter in the air on which water vapor condenses. Cone of confusion. A cone-shaped volume of airspace directly above a VOR station where no signal is received, causing the CDI to fluctuate…
Aviation Maintenance Technician Handbook - Airframe p. 2-29
Chapter 2: Aerodynamics, Aircraft Assembly, & Rigging › Stabilizer Systems › Bell Stabilizer Bar System
lead hinges (the whole rotor slows down and accelerates per turn). Two-bladed systems require a single teetering hinge and two coning hinges to permit modest coning of the rotor disc as thrust is increased. The configuration is known under ... multiple names, including Hiller panels, Hiller system, Bell-Hiller system, and flybar system. Offset Flapping Hinge The offset flapping hinge is offset from the center of the rotor hub and can produce powerful moments useful for controlling the helicopter…