ROTARY-WING HEAD AND CONTROLS
The forward and aft swashplates transmit manual or
automatic cockpit control movements to the rotary-wing
blades. The swashplates can be tilted and moved
vertically. This movement is transferred to the blades
through the pitch links and pitch-varying housings.
Forward and aft swashplates have aluminum rotating
rings. The stationary ring on the aft swashplate is steel.
On the forward swashplate this ring is aluminum. The
stationary ring of each swashplate is mounted on a
spherical bearing. This allows the swashplate to tilt
in any direction. A ball bearing connects rotating and
stationary rings. The swashplate is free to slide up or
down on a slider shaft to change blade pitch angle. Lugs
are provided on the rotating ring for connecting three
pitch links and an upper drive arm. Drive arm lugs are
located in two positions so the rotating ring can be used
on forward or aft swashplate. Lugs on the stationary
ring provide for connection of two servocylinders, fixed
link, and longitudinal cyclic trim actuator. Two single
interrupters and a double interruptor on the rotating ring,
and a magnetic pickup on the stationary ring, are used
for rotor balancing.
The six pitch links are connected between the
swashplates and pitch-varying housings. Tilting a
swashplate up or down moves the pitch link and pitch
arm in the same direction. This increases or decreases
the blade pitch angle. Raising or lowering the swashplate
on the slider shaft changes pitch on all three blades.