UFC 3-535-01
17 November 2005
CHAPTER 12: DESIGN AND INSTALLATION GUIDELINES
12-1
SPECIAL AIR FORCE REQUIREMENTS
12-1.1
General Guidelines
When design options exist and operational requirements do not dictate a clear choice
between them, base the decision on the results of a life cycle cost analysis rather than
the lowest first cost. All interior and exterior elements of the airfield lighting systems
must meet the requirements of this document. Refer to UFC 3-535-02, Design Drawings
for Visual Air Navigation Facilities, for detailed installation information.
12-1.2
Light Fixture Mounting
Wherever practical, mount the light fixtures on bases installed in a concrete envelope.
The mounting bases support the light fixture and normally house the isolation
transformer. For temporary construction the light fixtures may be stake mounted, and
the transformers may be surface mounted.
12-1.3
Concrete Foundations
All foundations for lights, signs, towers, and other equipment must be flush with the
grade and the surrounding area stabilized and compacted to prevent erosion and
excessive rutting in the event an aircraft strays from the pavement.
12-1.4
Cable and Duct Installation
Wherever practical, install cables in approved underground duct. Cable must be suitable
for underground installation, and installed either in concrete encased or direct buried
duct. Use concrete encased duct under paved areas. When installation under existing
pavement is required, the designer must select the best conduit for the application
considering strength and corrosion resistance. For temporary construction, the cables
may be direct buried. Make connections between the lighting cable, isolation
transformers, and light fixtures with FAA L-823 connectors. Cables for taxiway
centerline, runway centerline and touchdown zone lights may be installed in conduit or
in saw kerfs cut in the pavement. While direct installation in saw kerfs is permitted,
ensure the cable is constrained below the pavement surface and protected from
damage resulting from differential expansion or movement. Recommendations for the
designer to consider regarding cable and duct installation are contained in Table 12-1.
12-1.5
Equipment Grounding System
Install #6 copper AWG green-jacketed wires identified as an equipment ground, in ducts
with primary circuit and connect all light bases. Note, if used for approach lights without
a light base, connect ground to each light fixture and to the vault lighting system.
12-1.5.1
Ground Criteria
The ground wire serves as a safety ground, protecting against high voltages that could
be brought to the light base. As an alternative, each aviation light base will be grounded
with a ground rod. System safety ground wires are to be bonded only at the vault,
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