Futaba 9VHP - Manual (Page 7)

RUDDER
Rudder (tail rotor) mixing functions automatically provide trim changes and corrective
inputs to the tail rotor to compensate for changes in main rotor torque (due to changes in
the T/C stick position).
Revolution Mixing
Automatic trimming of the tail rotor neutral position is provided in response to Throttle/
Collective changes. As the T/C stick is raised above the center (hover) position, tail rotor
pitch is increased and is reduced when the stick is moved below the hover point. The
amount of trim change is adjustable in each direction from the T/C stick hover point (UP
and DOWN Mixing). The exact T/C stick hovering point is programed into the computer
using the HOVERING OFFSET screen (Seepage 32).
Acceleration Mixing
Acceleration Mixing is used primarily on "fixed
pitch" helicopters. This function provides a
momentary increase or decrease in tail rotor
pitch when the throttle is raised or lowered.
This compensates for momentary changes in
main rotor torque until the rotor speed stabilizes
at the new throttle setting. The rate at which the
momentary tail rotor input decays (DELAY) is
adjustable.
Rudder Offset
This function disconnects Revolution Mixing
(Pitch -> Rudder Mixing), and returns the rudder
servo to a preset neutral position. Rudder Offset
is used in forward flight when airflow over the
fuselage reduces the need for anti-torque force
from the tail rotor. Flight trim is improved, and
the power-robbing effect of the tail rotor is
reduced.
Setting Method
1) Select the EDIT screen and move the cursor
to Line 2 with the
the program key.
2) Select the RUDDER mixing screen by pressing
the program key.
ROTOR-DIR (Revolution Mixing Rotor
Direction Setting)
1) Move the cursor to the ROTOR-DIR line with
the cursor key.
2) Set the mixing direction by pressing the
program key when the main rotor rotates
clockwise and pressing the program key
when the main rotor rotates counterclock-
wise. The direction of rotation is indicated by
RIGHT or LEFT displayed in ( ).