runway lighting and
Runways may intersect each other. The
additional runways enable aircraft to land into the wind. Single runways
can be difficult if there is a strong crosswind. Where there is only one
runway, every effort is made to build the alignment in the direction of
the prevailing wind.
Runways are referred to after their compass
runway numbering system
A runway's compass
direction is indicated by a large number painted at the end of each
runway. A runway's number is not written in degrees, but is given a
shorthand format. For example, a runway with a marking of "14" is actually
close to (if not a direct heading of) 140 degrees. This is a southeast
compass heading. A runway with a marking of "31" has a compass heading of
310 degrees, that is, a northwest direction. For simplicity, the precise heading
is rounded off to the nearest tens. For example, runway 7 might have a
precise heading of 68 degrees, but is rounded off to 70 degrees. It is still
good practice to check your compass prior to take-off or landing as it has
been known that the numbers have been painted on the wrong ends!
click on the
runway numbers on the illustration below to see the direction that will be seen
on an aircraft's compass when it is ready to take off.
Occasionally there may be
parallel runways. 'L' and 'R' is then added to the runway number. Even
more rarely there are three parallel runways. The central runway is called
Below are shown
typical runway markings.
Relocation of a
Threshold with Markings for
Taxiway Aligned with Runway
It is relatively easy to navigate
around small airports, but large airports can be a nightmare for pilots using
them for the first few times. Pilots can inform the ground controller they are
unfamiliar with the airport, and request progressive taxi instructions. The
ground controllers are happy to help newcomers. The airborne view of Dallas/Ft.
Worth airport will give you a picture of how complex and confusing a large
airport can be to pilots who do not work out of DFW regularly. The view looking
north shows nine runways and dozens of taxiways and high-speed turnoffs.
Airports also use standardized
lighting to provide direction and identification to
all air and ground crews. To assist pilots in differentiating at night
between airport runways and major roads, airports have rotating beacon
lights. These beacons usually flash green and white lights to indicate a
civilian airport. These beacons are visible from the air long before the
entire airport is recognizable.
Military identification beacons flash
To help pilots at night quickly
identify the beginning of a runway, green threshold lights line the
runway's edge. Red lights mark the ends of runways and indicate
obstructions. Blue lights run alongside taxiways while runways have white
or yellow lights marking their edges. All these markings and lights serve
to set a safety standard for all pilots to follow.