Specifications
See also Tractor tail rotor
R
Retreating blade
The rotor blade which is moving with the wind created by helicopter motion, thus decreas-
ing its effective airspeed.
See also Advancing blade
Retreating blade stall
A situation in forward flight where the effective airspeed of the retreating blade approaches
zero. This can result in loss of helicopter control.
Revo mix/Revo mixing
A mixer which adds a percentage of the main rotor throttle to the tail rotor throttle to pre-
vent the heli from spinning. This is only used with yaw rate (non-heading hold) gyros be-
cause the yaw rate gyro only dampens tail movement and cannot maintain the direction of
the tail. If using a heading hold gyro, this option should be DISABLED on the transmitter
RFI
Radio Frequency Interference. RFI causes little "glitches" in your control and the heli will
twitch abruptly in one direction or another and/or the tail may suddenly jerk around.
Rotor
The rotating part of a motor. For a brushed motor, this includes the motor windings; for a
brushless motor, this includes the magnets.
See also Stator
Rudder
On an airplane, the vertically hinged plate which controls the course of the airplane. This is
equivalent to a helicopter's tail rotor.
Rudder Offset
A transmitter function that lets you specify an additional amount of rudder trim for idle-up
modes which usually have a higher RPM or different blade pitch curve and thus different
amounts of torque compensation. This function should be inhibited if using a heading hold
gyro.
Rx
Abbreviation for receiver. The portion of the radio system that is mounted in the helicopter
and adjusts the servos and speed controller(s) according to the signals from the Tx.
See also Tx
S
See-Saw Head
A form of rotor head where the two rotor blades are "connected" through a feathering shaft
so that when one pitches up the other pitches down. This makes for a more stable heli-
copter an a simpler design, but does not handle as well as a flapping head type.
Settling with Power
A dangerous condition when descending during a hover where the helicopter's rotor
blades descend into their own downwash. This can cause a crash if not handled properly.
Glossary
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