Installation Instructions

190-01007-A3 GTN 6XX/7XX AML STC Installation Manual
Rev. 4 Page 2-35
2.4.11 Cable and Wiring Considerations
Wiring should be installed in accordance with AC 43.13-1B Chapter 11, sections 8 through 13. The
following issues should be addressed:
• It should not be possible for the cable harness to be exposed to wire chafing;
• It should not be possible for a cable harness to be exposed to wire chafing in a manner that both
GPS units fail simultaneously;
• The cable harness should not be located near flight control cables, high capacity electrical lines
(e.g. DC electric motor cables) or fuel lines;
• The cable harness should be located in a protected area of the aircraft ( i.e. isolated from engine
rotor burst); and
• Do not route cable near high-energy sources. (i.e. DC motors, high heat sources)
• Wiring which is required to be shielded per the interconnect diagrams in Appendix E must be
shielded.
• Pigtail lengths must be less than 3.0 inches.
• For dual GTN unit installations, care should be taken to ensure separation between wires of
redundant systems to reduce the possibility of loss of navigation due to a single event.
Refer to Sections 3.3 and 3.6.7 for recommended coaxial cable types.
Refer to Appendix E and Appendix F for the appropriate wiring connections to assemble the wiring
connectors.
2.4.11.1 Pressurized Aircraft Considerations
In pressurized aircraft, wiring that penetrates the pressure vessel must be installed in accordance with the
Type Design of the aircraft. Any wires that penetrate the pressure bulkhead must use existing provisions
such as spare pins in the existing bulkhead connectors, or existing sealed wire through holes in
accordance with the aircraft maintenance manual.
Substantiation for additional holes in the pressure vessel is beyond the scope of this manual and would
require additional data from the aircraft manufacturer or other FAA approved data.
2.4.11.2 Coaxial Cable Considerations
When routing coaxial cables, observe the following precautions:
5. All cable routing should be kept as short and as direct as possible.
6. Avoid sharp bends.
7. Avoid routing cables near power sources (e.g., 400 Hz generators, trim motors, etc.) or near
power for fluorescent lighting.
See Section 3.6.6 for more information on the installation of coaxial cable.
2.4.11.3 Marker Beacon Antenna Cable Installation
When routing marker beacon antenna cables, observe the following precautions:
• All cable routing should be kept as short and as direct as possible.
• Avoid sharp bends.
• Avoid routing cables near power sources (e.g., 400 Hz generators, trim motors, etc.) or near
power for fluorescent lighting.
Avoid routing the marker beacon antenna cable near other antenna cables (e.g. ADF, COM, NAV, GS). See
Section 3.6.7 for marker beacon antenna termination technique.