Install Manual

Preliminary
SKY899
Installation Manual
4-15
Rev. A
The calibration value (000-359) is derived from a variety of measurements. Specific values are meaningless
however, in a failed TRC, a varying spread may indicate problems with the directional antenna system
(antenna, cables, or connectors) or the TRC.
If the calibration failed, the message “Calibration Failed!” will be displayed.
4.4.4. Ground Test
Ground Test initializes the system for on-the-ground testing. In this configuration, the barometric
altimeter is simulated to 50,000 ft, heading simulated to 0 degrees, and the radar altimeter simulated to
2,500 ft. Ground test menu is accessed by selecting that option from the Service Menu (i.e., press SEL with
Ground Test highlighted).
The Ground Test screen displays the following:
BRT
OFF
EXIT
SEL
Ground Test
Perform Ground Test
Selecting Perform Ground Test initializes the ground test software and displays the following:
BRT
OFF
NOTES
1. When the system is set to GROUND TEST, the barometric altimeter is
simulated to 50,000 ft and the heading simulated to 0 degrees.
2. Ground test is available only if the squat switch input indicates aircraft is on
the ground.
3. When the system is set to GROUND TEST, the radio altimeter simulated to
2,500 ft.