89000046-014
KSN 780/8XX/900 AeroNav AML STC Installation Manual for Helicopters
Rev 0
Page-4-3
© Honeywell International Inc. Do not copy without express permission of Honeywell.
4.7.2 Databus Wiring – New Installations
For all new installations of dual AeroNavs (not replacing pre-existing GNS4xx/5xx systems), the
recommended wiring for the RS-485 data protocol is shielded twisted- pair cable with an approximate
characteristic impedance of 100-120 Ohms. The wire material must meet 14 CFR 27.1359 (c).
4.8 Circuit Protection
Circuit Breakers must be installed in a location easily accessible to the pilot and must be resettable
trip free devices. The Circuit Breaker must be clearly identified and visible under all lighting
conditions. Circuit breaker size is identified in installation data shown in Appendix D: Electrical
Interface Drawings. Note that 14v aircraft may be required to replace the installed circuit breaker
and power wiring to accommodate the AeroNav XXX.
4.9 Power Distribution
Note: The references in the below images to the COM block are N/A for the AeroNav 880/780.
Aircraft installing one AeroNav XXX should connect the power and grounds as shown in Figure 3.
Avionics Bus
AeroNav 800/900
COM
Aircraft Ground
Single Avionics Bus
Figure 3 AeroNav XXX Power Distribution
Aircraft installing two should connect the power and grounds as shown in in Figure 4.
Avionics Bus 1
Avionics Bus 2
AeroNav 800/900
COM
AeroNav 800/900
COM
Aircraft Ground
Aircraft Ground
Avionics Bus
AeroNav 800/900
COM
AeroNav 800/900
COM
Aircraft Ground
Aircraft Ground
Preferred
Alternate
Figure 4 Dual AeroNav XXX Power Distribution