TASK 2 TRACK AND BALANCE MAIN ROTOR ON GROUND
1. If any measurements are above limits, do procedure 2.1.
2. If measurements are within limits, press the UP cursor to view measured values:
a.) If ground lateral is 0.2 ips or below and track spread is 0.25 inches or less, press QUIT to return to the
Main Menu. If tail rotor balance is known to be acceptable or previously balanced initiate task 3 FLIGHT
track and balance.
b.) If ground lateral is above 0.15 ips, further reduction should be easy and is encouraged. Press DO to
execute Diagnostics. Perform procedure 2.2.
Hub weights are defaulted to OFF and must be turned
on via Edit Adjustables, when needed.
Pitch link moves affect lateral vibration, but weight
moves do not affect track. Turning weights on and off
will not affect the magnitudes of the pitch link moves
suggested. Turning pitch links on and off, on the other
hand, will affect the weight moves suggested since pitch
link adjustments also affect lateral vibration. Therefore
never ignore any undesirable pitch link move, but turn
the unwanted adjustment off, re-compute the corrections
and re-examine the predictions. If this is not done, the
corrections will in most cases be less than optimum, and
the predictions will, in all cases, be in error.
PROCEDURE 2.1 PITCH LINK ONLY ADJUSTMENTS
To prevent a large autorotation adjustment later during
track and balance, the track can be adjusted to any one
blade (i.e. designated target) by using the EDIT
ADJUSTABLES function from the AVA diagnostic menu,
toggling off the desired blade (target) to be adjusted to,
and pressing DO. For example, if flat pitch torque is less
than 15%, adjust blades up to the highest blade by
toggling off highest blade and obtaining a solution. If the
torque is between 15% and 20%, use AVA
recommended default solution to adjust track to the
mean of the blades. If the torque is greater than 20%,
adjust blades down to the lowest blade by toggling off
lowest blade and obtaining a solution.
a. Press DO to calculate adjustments.
b. Examine the pitch link adjustments given.
1. If pitch link moves are 1 flat or more, record the indicated pitch link adjustments, go to procedure 3.
2. If pitch link moves are less than 1 flat, or if no pitch link adjustments are given, press QUIT. Select View
Predictions and press DO.
a.) If measured track is less than 0.25 inch, do procedure 2.2.
b.) If measured track is 0.25 inch or greater and if predicted lateral is 0.1 ips or greater, do procedure 2.3.
c.) If measured track is 0.25 inch or greater and if predicted lateral is less than 0.1 ips, record the pitch link
adjustments and do procedure 3.