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Airport Marking Aids and Signs

FIG 2−3−1

Precision Instrument Runway Markings

b. Runway Designators. Runway numbers and

letters are determined from the approach direction.

The runway number is the whole number nearest

one-tenth the magnetic azimuth of the centerline of

the runway, measured clockwise from the magnetic

north. The letters, differentiate between left (L),

right (R), or center (C) parallel runways, as


1. For two parallel runways “L” “R.”

2. For three parallel runways “L” “C” “R.”

c. Runway Centerline Marking. The runway

centerline identifies the center of the runway and

provides alignment guidance during takeoff and

landings. The centerline consists of a line of

uniformly spaced stripes and gaps.

d. Runway Aiming Point Marking. The aiming

point marking serves as a visual aiming point for a

landing aircraft. These two rectangular markings

consist of a broad white stripe located on each side of

the runway centerline and approximately 1,000 feet

from the landing threshold, as shown in FIG 2−3−1,

Precision Instrument Runway Markings.

e. Runway Touchdown Zone Markers. The

touchdown zone markings identify the touchdown

zone for landing operations and are coded to provide

distance information in 500 feet (150m) increments.

These markings consist of groups of one, two, and

three rectangular bars symmetrically arranged in

pairs about the runway centerline, as shown in

FIG 2−3−1. For runways having touchdown zone

markings on both ends, those pairs of markings which

extend to within 900 feet (270 m) of the midpoint

between the thresholds are eliminated.