GH-3100
Installation & Operation Manual
TP-559
Operation
Page 5-33
Revision K
March 30, 2017
5.3.5.8 TACAN Display Data
If the unit is configured for TACAN TRANSCEIVER and the pilot uses the Menu to select the TACAN
Mode in Normal operational state, the display data appear as the following:
•
TCNx descriptor where indicators are either TCN1 or TCN2
•
Left / Right deviation indicator
•
Selected Course digital readout
•
CRS descriptor
•
TO/FROM descriptor
•
Three digital data displays for respectively Distance, Ground speed and Time to Go, with Ground
speed and Time to Go being optional, depending on the pilot’s selections from the menu.
5.3.5.8.1 TACAN Descriptor
The source of the TACAN data is identified with the letters “TCN1” or “TCN2”.
5.3.5.8.2 Left / Right Deviation Indicator
The left/right deviation indicator reaches the 100% mark at a 10
°
course deviation. A positive course
deviation causes a right indicator movement. The resolution for one needle width of movement is a
minimum of 1 degree.
5.3.5.8.3 Selected Course
The Selected Course is entered from the main menu selection.
5.3.5.8.4 TO / FROM Ambiguity Indicator
When the Selected Course is displaced by more than
90°
±
0.1
°
from the current TACAN omnibearing,
the appropriate FROM indication is shown. When the Selected Course is displaced by less than or equal
to, plus or minus 90°
±
0.1
°
from the current TACAN omnibearing, the appropriate TO indication is
shown.
5.3.5.8.5 Course Auto-Center
Automatic course centering is done using the main menu. When the Course Auto-Center menu item is
selected, the Selected Course changes to the present TACAN omnibearing.
5.3.5.8.6 TACAN Data Resolution
The distance is shown in nautical miles with a resolution of 0.1 NM for distances under 100 NM, and a
resolution of 1.0 NM for distances of 100 NM and greater. The resolution of shown ground speed is 1
knot. The resolution of shown time-to-station is 1 minute.
5.3.5.8.7 TACAN Invalidities
A TACAN Invalidate term means that some set of conditions exist such that information that is received
or should have been received on the configured ARINC 429 input either is not received, is received with
the No Computed Data bit set, or other data errors.
All TACAN invalidity indications revert to a valid display when the conditions, which caused the
invalidity no longer, exist.
If an invalidity is detected the appropriate data is removed from the display or the data field is set to “---”
or/and the TCN descriptor may change color IAW the DCM configuration for NAV SOURCE FAILURE
COLOR”.
