| On these pages you will find information on different parts and features
of a typical radio controlled helicopter. To start with you will need a helicopter
kit with collective pitch control. It is recommended that you start with a good .30,
.40, .50, or .60 size kit. Each size helicopter has it's own advantages.
Generally speaking though each helicopter will perform more or less the same
maneuvers. Shown below is a picture of my modified Concept VR 46.
This helicopter was specially made for 3D hotdog maneuvers, but it definitely can be set
up for training the beginning flyer. Some of the helicopters parts have been labeled
in the diagram below, and I will go through and describe their operations.
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| On every helicopter there has to be a set of main
blades. These are what are used to propel the
the helicopter up and down, forward and backward, left and right, through loops, flips and
inverted flight maneuvers. The blades on an rc helicopter will typically be turning
at speeds between 1200 to 2200 rpm during flight.
Peculiar to helicopters in general, is the fact that the blades
or main rotor spins at an almost constant speed throughout all attitudes of flight.
For the helicopter to change its lateral or vertical rate of speed the angle of attack or
pitch of each blade must be increased or decreased. |
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 For the helicopter to move up or down the pitch of all the main blades
must be collectively increased or decreased. This is also referred to as increasing
or decreasing the collective pitch of the main blades.
For the helicopter to move laterally (sideways, backward or forward) the pitch of each
blade has to be increased or decreased in turn (feathered) to provide and increase in lift
under one side of the rotor disk, and a decrease in lift on the opposite side so as to
achieve lateral motion.
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 The mechanism that allows for the constant feathering of the
main blades is the swashplate. The
swashplate consists of two control surfaces. The lower section
which receives the directional commands from the servos, and in turn direct these control
inputs to the upper moving section of the swashplate. The
upper moving section turns with the main rotor blades feathering each blade on every
revolution. Both sections are linked to tilt by the gimbals or globe bearing in the
center. It is in the center of this globe bearing that the main rotor mast runs
through.On both the stationary and rotating control surfaces of the swashplate are ball
connections. These fit into the ball links on the pitch
control rods which connect up to the main blades, flybar, and mixing
levers. |
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