Page 389 - Planning and Design of Airports

340 Airp o r t D e sign

of 10 ft. Where there is no operational need for taxiway holding line
markings the signs may be installed in the area from the taxiway
point of tangency to the location where the holding line markings
would be installed [25].
Typical locations for taxiway guidance signs are shown in Fig. 8-37.
An illustration of the required signs and their placement for a basic
airport layout is given in Fig. 8-38 [25].
Sign Operation
Holding positions signs for runways, instrument landing system criti-
cal areas, approach areas, and their associated taxiway location signs
should be illuminated when the associated runway lights are illumi-
nated. Other taxiway signs should be illuminated when the associated
taxiway lights are illuminated.
The installation of retroreflective markings is not mandatory. How-
ever, it is quite economical, especially at airports where lights cannot be
justified because of the volume or nature of air traffic [12]. The marking
is very similar to that used successfully on highways for many years.

A A
STRAIGHT AHEAD
TAXIWAY

E E E E

A E E A A E
A A

(a) STANDARD 4-WAY (b) STRAIGHT AHEAD TAXIWAY HAS DIRECTION
INTERSECTION CHANGE GREATER THAN 25 DEGREES

F F A
STRAIGHT AHEAD
TAXIWAY

E E

E A F E A F A
A A

(c) DESIGNATION OF STRAIGHT (d) Y CONFIGURATION WITH TAXIWAY
AHEAD TAXIWAY HAS CHANGED ‘A’ CHANGING DIRECTION
FIGURE 8-37 Signage confi guration at taxiway intersections.