Installation Overview; Introduction; Minimum System Configuration - Garmin GPS 400W, GNC 420W Installation Manual

2. INSTALLATION OVERVIEW

2.1

Introduction

Always follow acceptable avionics installation practices per AC 43.13-1B, AC 43.13-2A, or later FAA
approved revisions of these documents. The GPS/WAAS installation instructions have been prepared to
meet the guidance material contained in AC 20-138A "Airworthiness Approval of Global Navigation
Satellite System (GNSS) Equipment". The communications installation instructions have been prepared
to meet the guidance material defined by AC 20-67B, "Airborne VHF Communications Equipment
Installations". Follow the installation procedure in this section, as it is presented, to accomplish a
successful installation. Read the entire section before beginning the work.
Prior to installation, consider the structural integrity of the 400W Series installation as defined in AC
43.13-2A, Chapter 1. Complete an electrical load analysis in accordance with AC 43.13-1B, Chapter 11,
on the aircraft prior to starting modification to ensure aircraft has the ability to carry the 400W Series
load. Refer to Section 3.12 to calculate the total power consumption of each 400W Series mode of
operation. Document the results of the electrical load analysis on the FAA Form 337.
Once the installation is complete, perform the post installation checkout before closing the work area in
case problems occur.
2.2

Minimum System Configuration

2.2.1 VFR Installation
The minimum 400W Series unit installation requires the following items for a VFR Installation:
•
GNS 400W Series unit (installed in the aircraft manufacturer approved location for 6.25 inch
wide avionics equipment).
•
GPS antenna is required for GPS navigation functions.
•
An external CDI is required for installations using VOR navigation and glideslope information.
•
A NAV antenna is required for VHF NAV functions.
•
A COM antenna is required for COM functions.
VFR installations must be placarded "GPS LIMITED TO VFR USE ONLY" in clear view of the pilot.
2.2.2 IFR GPS Installation
In order for the 400W Series unit to be utilized for IFR GPS Navigation, the criteria in Section 2.2.1 must
be met in addition to the following:
•
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 (GS) in order to perform VNAV operations / approaches.
•
Any annunciation required for Source Selection or IFR GPS Navigation must meet the
acceptable field-of-view requirements as noted in Section 2.5.1.
To take full advantage of the 400W Series unit capabilities, an optional barometric
altitude source is recommended for automatic sequencing of fix-to-altitude (FA) and
hold-to-altitude (HA) leg types. If no barometric altitude data is provided to the 400W
Series unit, FA and HA legs must be manually sequenced.
400W Series Installation Manual
190-00356-02
NOTE
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Rev. E