GDL 69/69A XM Satellite Radio
190-00355-00 Rev.E
Instructions for Continued Airworthiness
Page 6 of 8
NOTE
Failure of the GRC 10 (i.e. dead batteries) has no impact on normal aircraft operations
and is only used for passengers to control audio entertainment.
2.5 Periodic Maintenance Instructions
2.5.1 Annual Inspection
Operation of the GDL 69/69A and GRT 10 / GRC 10 is not permitted unless an inspection as described
in this section has been completed within the preceding 12 calendar months. Conduct a visual inspection
on the unit and its wire harness to insure continued installation integrity:
1. Inspect the unit for security of attachment.
2. Inspect the condition of wiring, routing, and attachment/clamping.
3. Verify the GDL 69/69A unit operation by viewing XM Satellite information on the control display
unit, or by checking the XM information or XM Status page on the control display unit. If GRT 10
and GRC 10 are installed, verify GRT 10 and GRC 10 operation by viewing XM radio channel
information on the GRC 10 display.
In addition, GDL 69A installations which use audio suppression inputs, verify each audio suppression
input for proper operation by the following step.
4. Verify the GDL 69A audio to the crew headphones is muted when each warning alarm is
activated. The stall warning may be activated by raising the stall vane on the leading edge of the
wing. The gear warning horn may be simulated by providing power or ground, as appropriate,
directly to the horn; provided the horn has been tested for proper operation when a gear
retraction test was performed.
2.5.2 Electrical Bonding Test
GDL 69 system electrical bonding must be tested every 2000 flight hours or ten (10) years, whichever is
first. If measured resistance is greater than Required Bonding in the following table, bonding must be
improved to meet applicable requirements for a new installation in accordance with the GDL 69/69A
Installation Manual Reference sections listed. LRUs must be disconnected from interfaced cables during
the measurements as detailed below. Reconnect LRUs after measurements and any required bonding
improvements are completed.
LRU
Required Bonding Installation Manual Reference
GDL 69
10 milliohm 2.4.2
XM antenna
10 milliohm 2.6.2
The GDL 69 measurement is made with connectors disconnected from the GDL 69. To accomplish this,
the backplate assembly with attached connectors can be removed from the GDL 69 mounting rack. The
bonding resistance is measured from the rack to airframe ground.
During the XM antenna measurement, any coax normally attached to the antenna must be disconnected.
Antenna bonding is measured from the XM connector (TNC external ground) on the antenna to a nearby
exposed portion of conductive aircraft structure (example: exposed rivet on fuselage stringer) or to the
ground plane for the antenna (such as the metallic ground plane added for non-metallic aircraft).
