M
ain Rotor Stability and Control
To fly properly and produce maximum lift, the rotor blades of your helicopter must be
adjusted correctly. This section contains information on setting up and tracking the
main rotor blades, and understanding helicopter stability and flight performance.
Refer to the
How Helicopters Work
section of this Operator’s Guide for more
information on main rotor systems.
Rotor Blade Designations
Lite Machines rotor blades each have a blade number that describes the blade
design and size. Series 1 blades, which are standard on
Model 110
and earlier
helicopters, are not marked. Blades having different numbers are incompatible with
each other, so do not use two blades with different numbers on the same rotor head.
Blade designations have thee parts: the series number, length and tip pitch. For
example, the blade designation S2 13 x 0 is read “series 2, 13 inch length, zero
degrees tip pitch”. Blade length is measured from the center of the flapping bolt hole
to the tip of the main rotor blade or from the center of the rotor shaft to the tip of the tail
rotor blade. Blade pitch is relative to the blade grip.
Warning!
Series 2 main rotor blades are susceptible to damage by solvents and other
chemicals.
DO NOT USE SOLVENTS, SUCH AS ACETONE, TO CLEAN THE MAIN
ROTOR BLADES! BLADES CLEANED WITH SOLVENTS CAN FAIL WITHOUT
WARNING WHEN ROTATING AT HIGH SPEED CAUSING SERIOUS INJURIES.
Use only soap or glass cleaners that are safe for plastic eye glass lenses.
Warning!
DO NOT ATTEMPT TO REPAIR DAMAGED ROTOR BLADES. REPAIRED
BLADES CAN FAIL WITHOUT WARNING WHEN ROTATING AT HIGH SPEED
AND CAUSE SERIOUS INJURIES.
Blade Tracking
The main rotor blades on your helicopter must operate at the same pitch angle. If
they do not, one blade will fly higher than the other causing an imbalance and
vibration. This vibration absorbs engine power and can damage the helicopter.
Before adjusting blade pitch, your first need to know which blade is pitched high and
which is pitched low. To do this, stick a 1/4" (6mm) wide piece of highly visible tape
(tracking tape) near the tip of one blade and another about an inch (25mm) from the
tip of the other blade. Don’t worry about causing an imbalance; you will remove the
tape when the blades are tracked.
Op er a tor's Guide
Main Rotor Stability and Control
LITE MA CHINES
5-1
