Installation Manual

Table Of Contents
Lynx NGT-9000
Installation Manual
0040-17001-01 (Revision W) Installation Page 2-30
2.3.11.3.1 Directional Antenna Location
Location is an important factor for maximum antenna performance. Optimum location for a particular
aircraft type is usually available from the aircraft manufacturer. See Figure 2-18 for Antenna Outline
dimensions.
1. In selecting a location, consider the following:
The mounting site should be on the top forward fuselage, as close to the centerline as possible,
and within -10° of the in-flight horizon (see Figure 2-17).
The optimum mounting point for maximum coverage is as far forward as possible without
exceeding the -10° forward pitch.
If necessary, consideration should be given to relocating other antennas to obtain the furthest
forward location for the directional antenna.
The antenna should be mounted on the aircraft with at least 20 dB isolation (about 30 inches
(76.2 cm)) from other L-band frequency antennas and 24 inches (61.0 cm) from other antennas
or obstructions.
The ground-plane should be as large as possible, a 30-inch (76.2 cm) ground-plane diameter is
recommended.
Refer to the guidelines given for the GPS Antenna and L-Band (UAT/1090) Antennas for
additional spacing requirements.
The directional antenna can be bottom mounted only if a suitable top mount location is not available.
Each bottom mount installation must be evaluated on a case-by-case basis. If further questions on the
bottom mount installation occur, contact Field Service Engineering at (623) 445-7070.
Note - The bottom mount directional antenna eliminates the diversity option.
Figure 2-17: Directional Antenna Mounting Location