Arlington Municipal Airport Development Plan Arlington Airport Development Plan | Page 127

vided to maintain the edge safety margin from the landing gear. When constructing new taxiways,
upgrading existing intersections should be undertaken to eliminate “judgmental oversteering,”
which is where the pilot must intentionally steer the cockpit outside the marked centerline in order
to assure the aircraft remains on the taxiway pavement.
2. Steering Angle: Taxiways should be designed such that the nose gear steering angle is no more
than 50 degrees, the generally accepted value to prevent excessive tire scrubbing.
3. Three-Node Concept: To maintain pilot situational awareness, taxiway intersections should pro-
vide a pilot a maximum of three choices of travel. Ideally, these are right and left angle turns and a
continuation straight ahead.
4. Intersection Angles: Design turns to be 90 degrees wherever possible. For acute angle intersec-
tions, standard angles of 30, 45, 60, 120, 135, and 150 degrees are preferred.
5. Runway Incursions: Design taxiways to reduce the probability of runway incursions.
- Increase Pilot Situational Awareness: A pilot who knows where he/she is on the airport is less
likely to enter a runway improperly. Complexity leads to confusion. Keep taxiway systems sim-
ple using the “three node” concept.
- Avoid Wide Expanses of Pavement: Wide pavements require placement of signs far from a pi-
lot’s eye. This is especially critical at runway entrance points. Where a wide expanse of pave-
ment is necessary, avoid direct access to a runway.
- Limit Runway Crossings: The taxiway layout can reduce the opportunity for human error. The
benefits are twofold – through simple reduction in the number of occurrences, and through a
reduction in air traffic controller workload.
- Avoid “High Energy” Intersections: These are intersections in the middle third of runways. By
limiting runway crossings to the first and last thirds of the runway, the portion of the runway
where a pilot can least maneuver to avoid a collision is kept clear.
- Increase Visibility: Right angle intersections, both between taxiways and runways, provide the
best visibility. Acute angle runway exits provide for greater efficiency in runway usage, but
should not be used as runway entrance or crossing points. A right angle turn at the end of a
parallel taxiway is a clear indication of approaching a runway.
- Avoid “Dual Purpose” Pavements: Runways used as taxiways and taxiways used as runways can
lead to confusion. A runway should always be clearly identified as a runway and only a runway.
- Indirect Access: Do not design taxiways to lead directly from an apron to a runway. Such con-
figurations can lead to confusion when a pilot typically expects to encounter a parallel taxiway.
- Hot Spots: Confusing intersections near runways are more likely to contribute to runway incur-
sions. These intersections must be redesigned when the associated runway is subject to recon-
struction or rehabilitation. Other hot spots should be corrected as soon as practicable.
6. Runway/Taxiway Intersections:
- Right Angle: Right-angle intersections are the standard for all runway/taxiway intersections,
except where there is a need for a high-speed exit. Right-angle taxiways provide the best visual
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