Garmin GPS 400W, Installation Manual

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Page 2-2 GNS 400W Series Installation Manual
Rev. G 190-00356-08
2.2.3 IFR VOR/LOC/GS Installation
The minimum GNS 430W installation requires the following items for an IFR VOR/LOC/GS
Installation:
GNS 430W (installed in the aircraft manufacturer approved location)
GPS antenna, VOR/LOC antenna, glideslope antenna, and COM antenna.
An External CDI/HSI indicator must be installed in the pilot‘s primary field-of-view (or in the
aircraft manufacturer approved mounting location). The indicator must have a vertical deviation
indicator for glideslope and VNAV operations/approaches.
Any annunciation required for Source Selection or IFR GPS Navigation must meet acceptable
field-of-view requirements.
2.3 External Sensors
When the 400W Series unit is installed with external sensors, these sensors must be installed in
accordance with the manufacturer's data. This manual does not provide information for the installation of
specific external sensors.
The 400W Series unit can accept data from multiple altitude, heading, and baro correction sources. If
multiple sources are used, the 400W Series unit will accept data as described below.
NOTE
Barometric altitude is not required by the 400W Series unit to meet the requirements of
TSO-C146a.
2.3.1 Multiple Uncorrected Pressure Altitude Sources
The 400W Series can accept altitude from a Gray code or RS-232 altitude encoder, fuel/air data computer
(FADC), ARINC 429 air data computer (ADC), ARINC 429 EFIS, and ARINC 429 traffic advisory
system.
If multiple sources of altitude data are supplied to the 400W Series unit, only valid data from the highest
priority source is used (input priority cannot be configured). If the highest priority source becomes
unavailable, data is taken from the next-highest priority source. The priorities of the altitude sources are
as follows (from highest to lowest):
1. ARINC 429 ADC
2. ARINC 429 EFIS
3. ARINC 429 traffic advisory system
4. RS-232 FADC
5. RS-232 Altitude Encoder
6. Parallel Altitude Encoder (Gray Code)