that the increase in size of the total complex does not exceed the specified size of the area previously
given for the GCA facility and RAPCON facility.
A14.2.7. Precision Approach Radar (PAR) Reflectors (Frangible and Non Frangible). Moving Target
Indicator (MTI) reflectors, or "target simulators," may be sited not less than 45.7 meters [150 feet]
from the near edge of a runway nor less than 38.1 meters [125 feet] from the near edge of a taxiway or
apron boundary marking to the centerline of the equipment. The height of these reflectors must be held
to a minimum consistent with the operational requirements of the system. MTI reflectors sited less
than 152.4 meters [500 feet] from the centerline of any runway must be of frangible construction, using
breakaway sections in reflector masts. Tracking reference reflectors must not be installed closer than
152.4 meters [500 feet] to the centerline of any runway, nor exceed 18.3 meters [60 feet] in height
above the centerline elevation of the nearest runway at the intersection of the equipment centerline
perpendicular with the runway centerline.
A14.2.8. Airborne Radar Approach Reflectors (Non Frangible). Airborne radar approach reflectors
may be placed not less than 99.1 meters [325 feet] from the runway edge and not less than 121.9
meters [400 feet] nor more than 228.6 meters [750 feet] from the runway centerline to the edge of the
equipment in a pattern parallel to the runway.
A14.2.9. Instrument Landing System (ILS):
A22.214.171.124. ILS Localizer Antennas (Frangible). For best operational benefit, the system should be
sited so that the antenna array is on the extended runway centerline, about 457.2 meters [1,500 feet]
beyond the stop end runway threshold. As a rule, siting must conform to approach-departure
clearance surface criteria discussed in Chapters 3 and 4. In some instances, local factors preclude
siting the unit at 457.2 meters [1,500 feet] from the runway. When the siting constitutes an
obstruction that cannot be waived, an offset from the extended runway centerline may be
considered (see A126.96.36.199.2 below). To be acceptable, an offset site must conform to paragraphs
A188.8.131.52.1 and A184.108.40.206.2 listed below:
A220.127.116.11.1. Angle of Divergence. Angle of divergence between the center of the localizer
course and the extended runway centerline must not exceed 3 degrees.
A18.104.22.168.2. Offset. Intersection of the centerline and localizer and the extended runway
centerline must occur at a point 335.3 meters [1,100 feet] to 365.8 meters [1,200 feet] toward
the runway threshold from the Decision Height (DH) point on the glide slope. If the
responsible facility engineering activity determines that an offset is feasible and the site is
152.4 meters [500 feet] or more from the runway centerline extended, the localizer may be
installed without a waiver of clearance criteria. However, a waiver to operational criteria,
TERPS, must be obtained as discussed in Attachment 2. These waivers will be processed at the
request of the responsible MAJCOM office, as discussed in Attachment 2.
A22.214.171.124.3. Far Field Monitor (FFM) (Frangible if mounted on a Low Impact Resistant
Supports, Non-Frangible if mounted on utility poles.). The FFM is considered part of the
localizer system. However, it is sited at the opposite end of the runway from the localizer
antenna array. Typical locations are 365.8 meters [1,200 feet] to 914.4 meters [3,000 feet] prior
to the landing threshold. FFM antenna height is determined by line of sight to the localizer
antenna array. The line of sight requirement can be relaxed if satisfactory localizer signal
reception is proven with a portable ILS receiver at the proposed lower height of the FFM site.
Just as with the localizer antenna array, the FFM antenna shall not penetrate the approach-
departure clearance surface criteria discussed in Chapters 3 and 4.