UFC 3-535-01
17 November 2005
5-4
TAXIWAY CLEARANCE BARS
5-4.1
Purpose
Clearance bars serve two purposes:
5-4.1.1
In low visibility, clearance bars warn pilots and vehicle drivers that they are
approaching a hold point (other than a runway holding position). They are installed at
designated hold points on the taxiway for operations below 600 feet (183 meters) RVR.
5-4.1.2
At night and in inclement weather, clearance bars warn pilots and vehicle
drivers that they are approaching an intersecting taxiway. They are generally installed at
taxiway intersections where the taxiway centerline lights do not follow the taxiway curve
and taxiway edge lights are not installed.
5-4.2
Configuration
A clearance bar consists of a row of three in-pavement yellow lights to indicate a low
visibility hold point. The fixtures are normally uni-directional but may be bi-directional
depending upon whether the hold point is intended to be used in one or two directions.
In addition, with the below exceptions, clearance bars are installed (without regard to
visibility) at a taxiway intersection with non-standard fillets or where the taxiway
centerline lights do not follow curves at intersections. Clearance bars installed for this
purpose consist of uni-directional fixtures.
5-4.2.1
Clearance bars may be omitted if taxiway edge lights are installed at the
intersection.
5-4.2.2
If the angle between the centerlines of any two adjacent segments of the
pavement is 90 degrees 10 degrees, clearance bars at a "T" or "+" shaped
taxiway/taxiway intersection may be substituted by or supplemented with an omni-
directional yellow taxiway intersection light (L-852E or F, as appropriate) installed near
the intersection of the centerline markings.
5-4.2.3
The clearance bar located on an exit taxiway may be omitted if it would be
located before, or within 200 feet (61 meters) beyond, a runway holding position (as
viewed while exiting the runway).
5-4.3
Location of a Clearance Bar Installed at a Low Visibility Hold Point
A low visibility hold point consists of a taxiway/taxiway holding position marking, a
geographic position marking, and a clearance bar. However, hold points are not
necessarily located at taxiway/taxiway intersections. In-pavement clearance bar lights
are centered on an imaginary line that is parallel to, and 610 millimeters (2 feet) from,
the holding side of the taxiway/taxiway holding position marking. The lights may vary
from this imaginary line up to 50 millimeters (2 inches) (perpendicular to the holding
position marking). If a conflict occurs with rigid pavement joints or other undesirable
spots, the taxiway/taxiway holding position marking, geographic position marking, and
the clearance bar may all be moved longitudinally any amount necessary to resolve the
conflict. However, if the hold point is located at a taxiway/taxiway intersection, the
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