Search results
Results from the WOW.Com Content Network
Abrasion strips on helicopter rotor blades are made of metal, often titanium or nickel, which are very hard, but less hard than sand. When a helicopter flies low to the ground in desert environments, sand striking the rotor blade can cause erosion. At night, sand hitting the metal abrasion strip causes a visible corona or halo around the rotor ...
Helicopter rotor joints Illustration of the shift in the location of the center of mass of a helicopter rotor caused by the individual blades' rotation in their respective vertical joints. Articulated rotor systems with drag hinges allow each blade to advance or lag in its rotation to compensate for the stress on the blade caused by the ...
The tips of the helicopter rotor blades move faster through the air than the parts of the blades near the hub, so they generate more lift, which pushes the tips of the blades upwards, resulting in a slight cone shape to the rotor disc. This is balanced by centrifugal force. If rotor RPM drops too low, the rotor blades fold up with no chance of ...
In a stationary hover, each rotor blade will experience the same airspeed at a constant RPM. In forward flight conditions, one rotor blade will be moving into the oncoming air stream while the other moves away from it. At certain airspeeds, this can create a dangerous condition in which the receding rotor blade stalls, causing unstable flight. [5]
The rotorhead is where the lift force from the rotor blades act. The rotorhead is connected to the main drive shaft via the Jesus nut, and houses several other components such as the swash plate, flight control linkages and fly-bars. [1] The rotor hub is also where the centre of gravity acts on the helicopter. The rotor head of a Sikorsky S-92
The rotor consists of a mast, hub and rotor blades. [citation needed] The mast is a cylindrical metal shaft that extends upwards from the transmission. At the top of the mast is the attachment point for the rotor blades called the hub. Main rotor systems are classified according to how the rotor blades are attached and move relative to the hub.
Static Rollover is a rolling action when the helicopter blades are not in rotation. When the rotor blades stop, the helicopter has the same principles of any other object and will roll if the static rollover critical angle is exceeded. Each helicopter has its own critical angle; this is a byproduct of its center-of-gravity.
A rotor blade produces more lift in the advancing half. As a blade moves toward the direction of flight, the forward motion of the aircraft increases the speed of the air flowing around the blade until it reaches a maximum when the blade is perpendicular to the relative wind. At the same time, a rotor blade in the retreating half produces less ...