Rotor Blade Tracking
Blade tracking is the process of determining the positions of the tips of the rotor blade relative to each other while the rotor head is turning, and of determining the corrections necessary to hold these positions within certain tolerances. The blades should all track one another as closely as possible. The purpose of blade tracking is to bring the tips of all blades into the same tip path throughout their entire cycle of rotation in the horizontal plane.
Flag and Pole
The flag and pole method shows the relative positions of the rotor blades in the horizontal plane. The blade tips are marked with chalk or grease with different colors, identifying each blade so that it will be possible to determine the relationship of one tip to the other tips of the rotor. This method can be used on all types of helicopters that do not have jet propulsion at the bladetips.