TASK 3 - BALANCE MAIN ROTOR ON THE GROUND
PROCEDURE 1: PREPARATION
Perform task 2, Flat Track Main Rotor on the Ground
PROCEDURE 2: PERFORM GROUND BALANCE (GNDBAL) MEASUREMENT
Use cursor keys to highlight Aircraft Type, then press DO.
Use cursor keys to highlight UH-60, and then press DO.
Tail Number is highlighted. Press DO.
Use cursor keys to highlight tail number used in task 2, then press DO.
Flight Plan is highlighted. Press DO.
Use cursor keys to highlight GNDBAL. Press DO.
Enter the Measurement mode by pressing F1. Verify that Test State FPG100 is highlighted.
Press DO when the aircraft is stable at the highlighted selection. Verify that the aircraft is at the required Test
State and press DO again. The AVA will acquire balance data and return to the selection menu.
After the measurement is completed, press DO on finish," then press DO on Diagnostics. If measurement is
within specified limits, press QUIT to Main Menu.
If measured values exceed manufacturer's desired levels, press the DO key to enter the DIAGS mode.
Perform all corrections displayed on the diagnostic screen. Do not use a partial set of adjustments. Run
procedure 2 again and verify that previously installed corrections brought aircraft ground balance to within
manufacturers recommended limits.
Blades Yellow and Red form one pair, Blue and Black
form the other. Weights should only be installed on one
blade of each pair.
Maximum weight allowed on one spindle is 5 pounds.
Weight of bolt and attaching hardware is approximately 2
Weight of balance washer (70106-08105-102) is
approximately 1 ounce. Weight of balance washer
(AN970-6) is approximately 1/2 ounce.
There are four locations to install balance weights: two
on the upper bracket and two on the lower bracket.
The weight of the attaching hardware must be included
in the total weight computation (see figure 9).
The maximum number of balance weights that can be
used per bolt is 18, with washer under bolt head
removed to obtain the 5-pound maximum. If the washer
under the nut is installed, the maximum number of
balance weights per bolt is 17.
Weight should be as equal as possible. 2 lbs. or less
use trailing bolt hole, over 2 lbs. divide weight equally
among all four-bolt holes.
k. Make appropriate logbook entry on the PCL and balance weights that were changed, if any.
Proceed to task 4.