ADS-B FDL-978 Series and
Lite Series Installation Manual
Document No. 87343 Rev G
FFS Copyright © 2016 All rights reserved.
3-51
3.6.2.17
GPS NAC Velocity
The GPS source used in the installation should have a navigation accuracy category for velocity
(NACv) setting specified by the GPS manufacturer. Use the GPS manufacturer’s setting to set
this. The following options are available for selection.
Unknown
10 meters/sec
3 meters/sec
GPS Auto
The display screen is as shown below with one of the options from the list above.
Rotate the CODE knob either clockwise or counterclockwise to display the options above and
select the correct GPS certification level. Once selected, press the ENT button to confirm your
selection and move to the next configuration item in the setup mode.
Unknown, 10 meters/sec, and 3 meters/sec are permanent set at installation in the software.
GPS Auto is automatically set from the velocity FOM (VFOM) data from the GPS unit. The
NACv value is hard-coded to broadcast no better than 3 meters/sec, even if GPS Auto is
selected.
For external position sources, contact the manufacturer to obtain the relevant data.
3.6.2.18
Aircraft Length
The aircraft length can be set from 1 meter to 75 meters by rotating the CODE knob either
clockwise or counterclockwise to display the correct length. Once selected, press the ENT
button to confirm selection and move to the next configuration item in the setup mode.
3.6.2.19
Aircraft Width
The aircraft width can be set from 1 meter to 80 meters by rotating the CODE knob either
clockwise or counterclockwise to display the correct width. Once selected, press the ENT button
to confirm selection and move to the next configuration item in the setup mode.
