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Disk loading of a hovering helicopter is the ratio of its weight to the total main rotor disk area. It is determined by dividing the total helicopter weight by the rotor disk area, which is the area swept by the blades of a rotor.
This three-engined helicopter has a single large main rotor and smaller tail rotor. On a helicopter, the main rotor or rotor system is the combination of several rotary wings (rotor blades) with a control system, that generates the aerodynamic lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic ...
Tilts main rotor disk left and right through the swashplate: Induces roll in direction moved To create movement to sides To move sideways Collective Collective angle of attack for the rotor main blades via the swashplate: Increase/decrease pitch angle of all main rotor blades equally, causing the aircraft to ascend/descend Increase/decrease torque.
If the engine fails, the freewheeling unit automatically disengages the engine from the main rotor, allowing the main rotor to rotate freely. The most common reason for autorotation is an engine malfunction or failure, but autorotation can also be performed in the event of a complete tail rotor failure, or following loss of tail-rotor ...
In aeronautics, a swashplate is a mechanical device that translates input via the helicopter flight controls into motion of the main rotor blades. Because the main rotor blades are spinning, the swashplate is used to transmit three of the pilot's commands from the non-rotating fuselage to the rotating rotor hub and mainblades.
Rotor stalls are not recoverable because the descending helicopter has airflow moving upwards through the rotor disc, so even full down collective will not restore normal airflow. When the helicopter rotor stalls, it does not do so symmetrically, because forward airspeed causes higher airspeed on the advancing blade than on the retreating blade.
In helicopters with coaxial rotors, the two rotor discs rotate in opposite senses. The dissymmetry of lift of one rotor disc is cancelled by the dissymmetry of lift of the other rotor disc. [citation needed] Tandem rotor helicopters such as the CH-47 Chinook still suffer from dissymmetry of lift, because the rotors are offset from one another ...
An actuator disk accelerating a fluid flow from right to left. In fluid dynamics, momentum theory or disk actuator theory is a theory describing a mathematical model of an ideal actuator disk, such as a propeller or helicopter rotor, by W.J.M. Rankine (1865), [1] Alfred George Greenhill (1888) and Robert Edmund Froude (1889).