Page 270 - Planning and Design of Airports

Geometric Design of the Airfield 231

Aerodrome Code Letter
A B C D E
Width
Pavement 7.5 10.5 15 * 18 † 23
Pavement and shoulder 25 38 44
Edge safety margin, U 1.5 2.25 3 ‡ 4.5 4.5
1
Strip 27 39 57 85 93
Graded portion of strip 22 25 25 38 44
Minimum separation
Taxiway centerline to taxiway centerline 21 31.5 46.5 68.5 81.5
Object 13.5 19.5 28.5 42.5 49
Aircraft stand taxilane to object 12 16.5 24.5 36 42.5

* 18 m if used by aircraft with a wheelbase equal to or greater than 18 m.
† 23 m is used by aircraft with an outer main gear wheel span equal to or greater than 9 m.
‡ 4.5 m. if intended to be used by airplane with a wheelbase equal to or greater than 18 m.
Source: International Civil Aviation Organization [2, 3, 4].
TABLE 6-20 Taxiway Dimensional Standards, m

separation is also applicable to aircraft traversing through a taxiway
on an apron or ramp. This separation may have to be increased to
accommodate pavement widening on taxiway curves. It is recom-
mended that a separation of at least 2.6 times the wheelbase of the
most demanding aircraft be provided to accommodate a 180° turn
when the pavement width is designed for tracking the nose wheel on
the centerline.
The taxilane centerline to a parallel taxilane centerline or fixed or
movable object separation in the terminal area is predicated on a
wingtip clearance of approximately half of that required for an apron
taxiway. This reduction in clearance is based on the consideration
that taxiing speed is low in this area, taxiing is precise, and special
guidance techniques and devices are provided. This requires a wing-
tip clearance or wingtip-to-object clearance of 0.1 times the wingspan
of the most demanding aircraft plus 10 ft. Therefore, this establishes
a minimum separation between the taxilane centerlines of 1.1 times
the wingspan of the most demanding aircraft plus 10 ft, and between
a taxilane centerline and a fixed or movable object of 0.6 times the
wingspan of the most demanding aircraft plus 10 ft [6]. Therefore,
when dual parallel taxilanes are provided in the terminal apron area,
the taxilane object-free area becomes 2.3 the wingspan of the most
demanding aircraft plus 30 ft.