SAC "H" Helipad, Manual

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SOUTHERN AVIONICS COMPANY
“H” Antenna 2-1 Planning
2 Planning
The following factors should be considered when planning the location of the helipad antenna.
The following figures show installation of antennas to various styles of helipads.
1. By using the following figures, and also the transmitter installation instructions, determine the
suitability of mounting locations for the radiobeacon transmitter and antenna coupler.
•
Provide accessibility for maintenance.
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Provide an unobstructed path from the antenna wire to the antenna coupler feed-through
insulator.
•
Keep the antenna feed wire out of personnel reach. High RF voltages are present on the
wire.
•
Provide sufficient guardrail mounting space for transmitter and antenna coupler
mounting. Approximately 6 feet (2 meters) may be required.
•
Provide for availability of electrical power.
2. Determine the appropriate antenna wire path.
•
Avoid excessive shielding of the antenna wire by adjacent decks and structures.
•
Maintain at least 12 feet (4 meters) separation between refuelling facilities and the
antenna wire and transmitter/antenna coupler site.
•
Avoid the extension of the antenna wire into personnel areas.
•
Avoid areas used in crane operations.
3. Determine the mounting points for the antenna supports.
•
Locate the antenna insulator support poles over the safety net support posts. (See Figure
“Final Tightening of Bands.”)
•
Locate the antenna insulator support poles over the safety net support poles at the wire
ends and the platform corners.
•
On square helipads of up to 36 feet (11 meters) on a side, not including the width of the
safety net, do not install any additional antenna insulator support poles between the
corner poles. On square helipads of 36 to 70 feet (11 to 21 meter), install one insulator
support pole between the corner poles. On octagonal and hexagonal platforms, install
corner insulator support poles only.
Note: Although eight antenna insulator support poles are furnished, all poles may not be required
for every installation. Unused insulators and poles should be stored for replacement use.