TASK 3 TRACK AND BALANCE FWD AND AFT ROTORS (HOVER)
PROCEDURE 1: CONFIGURE AVA FOR HOVER RUN
a. Perform task 1, Test Equipment Installation/Checkout, procedures 1 through 6.
b. Turn on DAU.
c. Turn on CADU.
d. Operate aircraft in a hover.
PROCEDURE 2: PERFORM HOVER MEASUREMENT
a. Press QUIT on the CADU until all selections show undefined.
b. Select CH47 under Aircraft Type menu.
c. Select proper tail number from previous selections in Tail Number menu or enter a new tail number (up to seven
d. Enter the Flight Plan menu and select HOVER.
e. Enter the MEASURE mode by pressing F1. Verify that HOVER is selected.
f. Press DO when the aircraft is stable at the proper test condition. Re-verify that the aircraft is at the required
Test State and press DO again. The AVA will acquire track and vibration data and return to the selection
display when the system is ready for the next measurement.
g. After the measurement is completed, press DO on Finish, press DO on Diagnostics. If measurements are
within specified limits, press QUIT to Main Menu and select next flight plan (FLIGHT).
Evaluate the ability to use the recommended
adjustments. If modifications to the adjustments are
desired, enter the menu option Edit Adjustables. Make
the desired changes and press the DO key.
h. If measured values exceed manufacturers desired levels, press the DO key to enter the Diagnostics mode.
Perform all corrections displayed on the correction screens. Check to ensure that all screens of a multiple
screen solution have been performed. If alterations of these corrective actions are desired, use the Edit
Adjustables and Edit Defaults diagnostic editors. See figure 12 for a detailed flow chart concerning HOVER
Do not use a partial set of the adjustments. The
recommended adjustments have accounted for the cross
coupling effects of the tandem rotors and using a partial
set of the corrections may increase the total vibration
Make corrective adjustments in accordance with TM 55-
i. If any adjustments have been made, perform the flight test again and verify the corrections.