The wind tunnel tests proved the SRC would be stable at low and high rotor speeds and during the transition from vertical flight to forward flight, says SiMiCon designer Vegard Evjen Hovstein.
42.
The throttle, on the other hand, is modulated automatically to maintain a constant rotor speed and is usually at its lowest value when the throttle stick is centered and the pitch is 0.
43.
The vast majority of helicopters maintain a constant rotor speed ( RPM ) during flight, leaving the angle of attack of the blades as the sole means of adjusting thrust from the rotor.
44.
In reference to the figure illustrated in the blade forces section, it is evident that the angle between the apparent wind speed and the plane of rotation is dependent upon the rotor speed.
45.
The tail rotor is driven from the main transmission, via the two directional gearboxes which provide a tail rotor speed approximately six times that of the main rotor to increase tail rotor effectiveness.
46.
In many cases, instead of expressing rotor speeds ( N 1, N 2 ) as RPM on cockpit displays, pilots are provided with the speeds expressed as a percentage of the design point speed.
47.
The size resolution of this method scales approximately with the square of the particle radii, and by adjusting the rotor speed of the experiment size-ranges from 100 Da to 10 GDa can be covered.
48.
Many full-sized ( and model ) rotorcraft have mechanically interconnected main and tail rotors so that when changing main rotor speed ( and hence yaw torque ), the tail rotor follows suit to compensate.
49.
Autorotation is permitted mechanically because of both a freewheeling unit, which allows the main rotor to continue turning even if the engine is not running, as well as aerodynamic forces of relative wind maintaining rotor speed.
50.
The fuel system is designed to control and govern the engine under all operating conditions and to provide safeguards against malfunctions, the pilot selecting rotor speed and the governing element automatically maintaining the rotor speed within close limits under varying conditions of load.
