Arlington Municipal Airport Development Plan Arlington Airport Development Plan | Page 117

Since the interim guidance only addresses a new or modified RPZ, existing incompatibilities are essen-
tially grandfathered under certain circumstances. While it is still necessary for the airport sponsor to
take all reasonable actions to meet the RPZ design standard, FAA funding priority for certain actions,
such as relocating existing roads in the RPZ, will be determined on a case by case basis.
RPZs have been further designated as approach and departure RPZs. The approach RPZ is a function of
the AAC and approach visibility minimums associated with the approach runway end. The departure
RPZ is a function of the AAC and departure procedures associated with the runway. For a particular
runway end, the more stringent RPZ requirements (usually associated with the approach RPZ) will gov-
ern the property interests and clearing requirements that the airport sponsor should pursue.
As depicted on Exhibit 3E, the existing RPZs associated with each runway end have incompatibilities.
The approach and departure RPZs beyond the Runway 16 end extend beyond airport property and
over a portion of the outer road associated with U.S. Interstate 20. A large portion of the property
within these RPZs is controlled by an avigation easement. On the opposite end of the runway, the ap-
proach and departure RPZs are traversed by Southeast Green Oaks Boulevard. The outer portions of
these RPZs also extend beyond airport property, but fall within an area controlled by the Airport via an
avigation easement. The approach RPZ extends farther south and includes portions of South Collins
Street, as well as approximately nine residential homes. The approach RPZ serving Runway 34 is signif-
icantly larger than the one associated with Runway 16 due to the instrument approach procedure
providing visibility minimums down to ½-mile.
As previously discussed, the Airport has upgraded the approach lighting system serving Runway 34 to
include a medium intensity approach lighting system with runway alignment indicator lights (MALSR).
The MALSR allows for improved visibility minimums down to ½-mile. Currently, the visibility minimums
associated with the ILS and global positioning system (GPS) localizer performance with vertical guid-
ance (LPV) approach procedures to Runway 34 are ½-mile. Further examination of the RPZs associated
with each end of Runway 16-34 will be undertaken later in this study.
RUNWAY/TAXIWAY SEPARATION
The design standard for the required separation between runways and parallel taxiways is a function of
the critical design aircraft and the instrument approach visibility minimum. The separation standard
for RDC C-II with lower than ¾-mile visibility minimums is 400 feet from the runway centerline to the
parallel taxiway centerline. For RDC C-III, the separation standard is also 400 feet. Parallel Taxiways A
and G are 400 feet from the runway; therefore, the current location of both parallel taxiways meet
both current and proposed design standards.
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